Space

.github/workflows/run-nmage.yml

@@ -0,0 +1,22 @@
+name: build-nmage
+on:
+  create:
+  workflow_dispatch:
+
+jobs:
+  build-nmage-macos:
+    runs-on: macos-10.15
+    steps:
+      - name: Install golang 1.17
+        uses: actions/setup-go@v2
+        with:
+          go-version: '^1.17'
+      - name: Install assimp-go dylib
+        run: sudo mkdir -p /usr/local/lib && sudo wget https://github.com/bloeys/assimp-go/releases/download/v0.4.2/libassimp_darwin_amd64.dylib -O /usr/local/lib/libassimp.5.dylib
+      - name: Install SDL2
+        run: brew install sdl2{,_image,_mixer,_ttf,_gfx} pkg-config
+      - name: Clone nmage
+        run: git clone https://github.com/bloeys/nmage
+      - name: build nmage
+        working-directory: nmage
+        run: go build .

.gitignore

@@ -15,3 +15,4 @@
 vendor/
 .vscode/
 imgui.ini
+*~

README.md

@@ -1,5 +1,7 @@
 # nMage
 
+[![build](https://github.com/bloeys/nmage/actions/workflows/run-nmage.yml/badge.svg)](https://github.com/bloeys/nmage/actions/workflows/run-nmage.yml)
+
 nMage is a (hopefully!) high performance 3D Game Engine written in Go being developed [live](https://twitch.tv/bloeys), with recordings posted on [YouTube](https://www.youtube.com/channel/UCCf4qyNGPVwpj1HYFGahs_A).
 
 This project is being built with the goals being (in no particular order):
@@ -17,8 +19,9 @@ To run the project you need:
 * A C/C++ compiler installed and in your path
   * Windows: [MingW](https://www.mingw-w64.org/downloads/#mingw-builds) or similar
   * Mac/Linux: Should be installed by default, but if not try [GCC](https://gcc.gnu.org/) or [Clang](https://releases.llvm.org/download.html)
-* Get the required [assimp-go](https://github.com/bloeys/assimp-go) DLLs/DyLibs and place them correctly by following the `assimp-go` [README](https://github.com/bloeys/assimp-go#using-assimp-go).
+* Install SDL2 by following their [requirements](https://github.com/veandco/go-sdl2#requirements).
+* Get the required [assimp-go](https://github.com/bloeys/assimp-go) DLLs/DyLibs and place them correctly by following the assimp-go [README](https://github.com/bloeys/assimp-go#using-assimp-go).
 
-Then run nMage with `go run .`
+Then you can start nMage with `go run .`
 
-> Note: that it might take a while to run the first time because of downloading/compiling dependencies.
+> Note: It *might* take a while to clone/run the first time because of downloading/compiling dependencies.

assert/assert.go

@@ -0,0 +1,12 @@
+package assert
+
+import (
+	"github.com/bloeys/nmage/consts"
+	"github.com/bloeys/nmage/logging"
+)
+
+func T(check bool, msg string) {
+	if consts.Debug && !check {
+		logging.ErrLog.Panicln("Assert failed:", msg)
+	}
+}

asserts/asserts.go

@@ -1,18 +0,0 @@
-package asserts
-
-import (
-	"github.com/bloeys/nmage/consts"
-	"github.com/bloeys/nmage/logging"
-)
-
-func True(check bool, msg string) {
-	if consts.Debug && !check {
-		logging.ErrLog.Panicln(msg)
-	}
-}
-
-func False(check bool, msg string) {
-	if consts.Debug && check {
-		logging.ErrLog.Panicln(msg)
-	}
-}

assets/assets.go

@@ -0,0 +1,32 @@
+package assets
+
+var (
+	Textures     map[uint32]Texture = make(map[uint32]Texture)
+	TexturePaths map[string]uint32  = make(map[string]uint32)
+)
+
+func AddTextureToCache(t Texture) {
+
+	if t.Path != "" {
+		if _, ok := TexturePaths[t.Path]; ok {
+			return
+		}
+		println("Loaded texture from path:", t.Path)
+		Textures[t.TexID] = t
+		TexturePaths[t.Path] = t.TexID
+		return
+	}
+
+	println("Loaded in-mem texture with ID:", t.TexID)
+	TexturePaths[t.Path] = t.TexID
+}
+
+func GetTextureFromCacheID(texID uint32) (Texture, bool) {
+	tex, ok := Textures[texID]
+	return tex, ok
+}
+
+func GetTextureFromCachePath(path string) (Texture, bool) {
+	tex, ok := Textures[TexturePaths[path]]
+	return tex, ok
+}

assets/textures.go

@@ -0,0 +1,157 @@
+package assets
+
+import (
+	"bytes"
+	"image"
+	"image/color"
+	"image/png"
+	"os"
+	"unsafe"
+
+	"github.com/go-gl/gl/v4.1-core/gl"
+)
+
+type ColorFormat int
+
+const (
+	ColorFormat_RGBA8 ColorFormat = iota
+)
+
+type Texture struct {
+	//Path only exists for textures loaded from disk
+	Path   string
+	TexID  uint32
+	Width  int32
+	Height int32
+	Pixels []byte
+}
+
+type TextureLoadOptions struct {
+	TryLoadFromCache bool
+	WriteToCache     bool
+	GenMipMaps       bool
+}
+
+func LoadTexturePNG(file string, loadOptions *TextureLoadOptions) (Texture, error) {
+
+	if loadOptions == nil {
+		loadOptions = &TextureLoadOptions{}
+	}
+
+	if loadOptions.TryLoadFromCache {
+		if tex, ok := GetTextureFromCachePath(file); ok {
+			return tex, nil
+		}
+	}
+
+	//Load from disk
+	fileBytes, err := os.ReadFile(file)
+	if err != nil {
+		return Texture{}, err
+	}
+
+	img, err := png.Decode(bytes.NewReader(fileBytes))
+	if err != nil {
+		return Texture{}, err
+	}
+
+	tex := Texture{
+		Path:   file,
+		Width:  int32(img.Bounds().Dx()),
+		Height: int32(img.Bounds().Dy()),
+		Pixels: make([]byte, img.Bounds().Dx()*img.Bounds().Dy()*4),
+	}
+
+	//NOTE: Load bottom left to top right because this is the texture coordinate system used by OpenGL
+	//NOTE: We only support 8-bit channels (32-bit colors) for now
+	i := 0
+	for y := img.Bounds().Dy() - 1; y >= 0; y-- {
+		for x := 0; x < img.Bounds().Dx(); x++ {
+
+			c := color.NRGBAModel.Convert(img.At(x, y)).(color.NRGBA)
+
+			tex.Pixels[i] = c.R
+			tex.Pixels[i+1] = c.G
+			tex.Pixels[i+2] = c.B
+			tex.Pixels[i+3] = c.A
+
+			i += 4
+		}
+	}
+
+	//Prepare opengl stuff
+	gl.GenTextures(1, &tex.TexID)
+	gl.BindTexture(gl.TEXTURE_2D, tex.TexID)
+
+	// set the texture wrapping/filtering options (on the currently bound texture object)
+	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.REPEAT)
+	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.REPEAT)
+	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
+	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
+
+	// load and generate the texture
+	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA8, tex.Width, tex.Height, 0, gl.RGBA, gl.UNSIGNED_BYTE, unsafe.Pointer(&tex.Pixels[0]))
+
+	if loadOptions.GenMipMaps {
+		gl.GenerateMipmap(tex.TexID)
+	}
+
+	if loadOptions.WriteToCache {
+		AddTextureToCache(tex)
+	}
+
+	return tex, nil
+}
+
+func LoadTextureInMemImg(img image.Image, loadOptions *TextureLoadOptions) (Texture, error) {
+
+	if loadOptions == nil {
+		loadOptions = &TextureLoadOptions{}
+	}
+
+	tex := Texture{
+		Width:  int32(img.Bounds().Dx()),
+		Height: int32(img.Bounds().Dy()),
+		Pixels: make([]byte, img.Bounds().Dx()*img.Bounds().Dy()*4),
+	}
+
+	//NOTE: Load bottom left to top right because this is the texture coordinate system used by OpenGL
+	//NOTE: We only support 8-bit channels (32-bit colors) for now
+	i := 0
+	for y := img.Bounds().Dy() - 1; y >= 0; y-- {
+		for x := 0; x < img.Bounds().Dx(); x++ {
+
+			c := color.NRGBAModel.Convert(img.At(x, y)).(color.NRGBA)
+
+			tex.Pixels[i] = c.R
+			tex.Pixels[i+1] = c.G
+			tex.Pixels[i+2] = c.B
+			tex.Pixels[i+3] = c.A
+
+			i += 4
+		}
+	}
+
+	//Prepare opengl stuff
+	gl.GenTextures(1, &tex.TexID)
+	gl.BindTexture(gl.TEXTURE_2D, tex.TexID)
+
+	// set the texture wrapping/filtering options (on the currently bound texture object)
+	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.REPEAT)
+	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.REPEAT)
+	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
+	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
+
+	// load and generate the texture
+	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA8, tex.Width, tex.Height, 0, gl.RGBA, gl.UNSIGNED_BYTE, unsafe.Pointer(&tex.Pixels[0]))
+
+	if loadOptions.GenMipMaps {
+		gl.GenerateMipmap(tex.TexID)
+	}
+
+	if loadOptions.WriteToCache {
+		AddTextureToCache(tex)
+	}
+
+	return tex, nil
+}

buffers/buf_usage.go

@@ -0,0 +1,33 @@
+package buffers
+
+import (
+	"fmt"
+
+	"github.com/bloeys/nmage/assert"
+	"github.com/go-gl/gl/v4.1-core/gl"
+)
+
+type BufUsage int
+
+const (
+	//Buffer is set only once and used many times
+	BufUsage_Static BufUsage = iota
+	//Buffer is changed a lot and used many times
+	BufUsage_Dynamic
+	//Buffer is set only once and used by the GPU at most a few times
+	BufUsage_Stream
+)
+
+func (b BufUsage) ToGL() uint32 {
+	switch b {
+	case BufUsage_Static:
+		return gl.STATIC_DRAW
+	case BufUsage_Dynamic:
+		return gl.DYNAMIC_DRAW
+	case BufUsage_Stream:
+		return gl.STREAM_DRAW
+	}
+
+	assert.T(false, fmt.Sprintf("Unexpected BufUsage value '%v'", b))
+	return 0
+}

buffers/buffers.go

@@ -5,169 +5,127 @@ import (
 	"github.com/go-gl/gl/v4.1-core/gl"
 )
 
-type BufGLType int
-
-const (
-	BufGLTypeUnknown BufGLType = 0
-	//Generic array of data. Should be used for most data like vertex positions, vertex colors etc.
-	BufGLTypeArray   BufGLType = gl.ARRAY_BUFFER
-	BufGLTypeIndices BufGLType = gl.ELEMENT_ARRAY_BUFFER
-)
-
-type BufType int
-
-const (
-	BufTypeUnknown BufType = iota
-	BufTypeVertPos
-	BufTypeColor
-	BufTypeIndex
-	BufTypeNormal
-)
-
-func (bt BufType) GetBufferGLType() BufGLType {
-	switch bt {
-
-	case BufTypeNormal:
-		fallthrough
-	case BufTypeColor:
-		fallthrough
-	case BufTypeVertPos:
-		return BufGLTypeArray
-
-	case BufTypeIndex:
-		return BufGLTypeIndices
-	default:
-		logging.WarnLog.Println("Unknown BufferType. BufferType: ", bt)
-		return BufGLTypeUnknown
-	}
-}
-
-type BufUsage int
-
-const (
-	//Buffer is set only once and used many times
-	BufUsageStatic BufUsage = gl.STATIC_DRAW
-	//Buffer is changed a lot and used many times
-	BufUsageDynamic BufUsage = gl.DYNAMIC_DRAW
-	//Buffer is set only once and used by the GPU at most a few times
-	BufUsageStream BufUsage = gl.STREAM_DRAW
-)
-
 type Buffer struct {
-	ID     uint32
-	Type   BufType
-	GLType BufGLType
-	DataTypeInfo
-
-	//DataLen is the number of elements in the uploaded to the buffer
-	DataLen int32
-}
-
-func (b *Buffer) Activate() {
-	gl.BindBuffer(uint32(b.GLType), b.ID)
-}
-
-func (b *Buffer) Deactivate() {
-	gl.BindBuffer(uint32(b.GLType), 0)
-}
-
-type BufferObject struct {
 	VAOID uint32
-	VertPosBuf *Buffer
-	NormalBuf  *Buffer
-	ColorBuf   *Buffer
-	IndexBuf   *Buffer
+	//BufID is the ID of the VBO
+	BufID uint32
+	//IndexBufID is the ID of the index/element buffer
+	IndexBufID    uint32
+	IndexBufCount int32
+	Stride        int32
+
+	layout []Element
 }
 
-func (bo *BufferObject) GenBuffer(data []float32, bufUsage BufUsage, bufType BufType, bufDataType DataType) {
-
-	gl.BindVertexArray(bo.VAOID)
-
-	//Create vertex buffer object
-	var vboID uint32
-	gl.GenBuffers(1, &vboID)
-	if vboID == 0 {
-		logging.ErrLog.Println("Failed to create openGL buffer")
+func (b *Buffer) Bind() {
+	gl.BindVertexArray(b.VAOID)
 }
 
-	buf := &Buffer{
-		ID:           vboID,
-		Type:         bufType,
-		GLType:       bufType.GetBufferGLType(),
-		DataTypeInfo: GetDataTypeInfo(bufDataType),
-		DataLen:      int32(len(data)),
-	}
-	bo.SetBuffer(buf)
-
-	//Fill buffer with data
-	gl.BindBuffer(uint32(buf.GLType), buf.ID)
-	gl.BufferData(uint32(buf.GLType), int(buf.DataTypeInfo.ElementSize)*len(data), gl.Ptr(data), uint32(bufUsage))
-
-	//Unbind everything
-	gl.BindVertexArray(0)
-	gl.BindBuffer(uint32(buf.GLType), 0)
-}
-
-func (bo *BufferObject) GenBufferUint32(data []uint32, bufUsage BufUsage, bufType BufType, bufDataType DataType) {
-
-	gl.BindVertexArray(bo.VAOID)
-
-	//Create vertex buffer object
-	var vboID uint32
-	gl.GenBuffers(1, &vboID)
-	if vboID == 0 {
-		logging.ErrLog.Println("Failed to create openGL buffer")
-	}
-
-	buf := &Buffer{
-		ID:           vboID,
-		Type:         bufType,
-		GLType:       bufType.GetBufferGLType(),
-		DataTypeInfo: GetDataTypeInfo(bufDataType),
-		DataLen:      int32(len(data)),
-	}
-	bo.SetBuffer(buf)
-
-	//Fill buffer with data
-	gl.BindBuffer(uint32(buf.GLType), buf.ID)
-	gl.BufferData(uint32(buf.GLType), int(buf.DataTypeInfo.ElementSize)*len(data), gl.Ptr(data), uint32(bufUsage))
-
-	//Unbind everything
-	gl.BindVertexArray(0)
-	gl.BindBuffer(uint32(buf.GLType), 0)
-}
-
-func (bo *BufferObject) SetBuffer(buf *Buffer) {
-
-	switch buf.Type {
-	case BufTypeVertPos:
-		bo.VertPosBuf = buf
-	case BufTypeNormal:
-		bo.NormalBuf = buf
-	case BufTypeColor:
-		bo.ColorBuf = buf
-	case BufTypeIndex:
-		bo.IndexBuf = buf
-	default:
-		logging.WarnLog.Println("Unknown buffer type in SetBuffer. Type:", buf.Type)
-	}
-}
-
-func (bo *BufferObject) Activate() {
-	gl.BindVertexArray(bo.VAOID)
-}
-
-func (bo *BufferObject) Deactivate() {
+func (b *Buffer) UnBind() {
 	gl.BindVertexArray(0)
 }
 
-func NewBufferObject() *BufferObject {
+func (b *Buffer) SetData(values []float32) {
 
-	var vaoID uint32
-	gl.GenVertexArrays(1, &vaoID)
-	if vaoID == 0 {
+	gl.BindVertexArray(b.VAOID)
+	gl.BindBuffer(gl.ARRAY_BUFFER, b.BufID)
+
+	sizeInBytes := len(values) * 4
+	if sizeInBytes == 0 {
+		gl.BufferData(gl.ARRAY_BUFFER, 0, gl.Ptr(nil), BufUsage_Static.ToGL())
+	} else {
+		gl.BufferData(gl.ARRAY_BUFFER, sizeInBytes, gl.Ptr(&values[0]), BufUsage_Static.ToGL())
+	}
+
+	gl.BindVertexArray(0)
+	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
+}
+
+func (b *Buffer) SetDataWithUsage(values []float32, usage BufUsage) {
+
+	gl.BindVertexArray(b.VAOID)
+	gl.BindBuffer(gl.ARRAY_BUFFER, b.BufID)
+
+	sizeInBytes := len(values) * 4
+	if sizeInBytes == 0 {
+		gl.BufferData(gl.ARRAY_BUFFER, 0, gl.Ptr(nil), usage.ToGL())
+	} else {
+		gl.BufferData(gl.ARRAY_BUFFER, sizeInBytes, gl.Ptr(&values[0]), usage.ToGL())
+	}
+
+	gl.BindVertexArray(0)
+	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
+}
+
+func (b *Buffer) SetIndexBufData(values []uint32) {
+
+	b.IndexBufCount = int32(len(values))
+	gl.BindVertexArray(b.VAOID)
+	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, b.IndexBufID)
+
+	sizeInBytes := len(values) * 4
+	if sizeInBytes == 0 {
+		gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, 0, gl.Ptr(nil), BufUsage_Static.ToGL())
+	} else {
+		gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, sizeInBytes, gl.Ptr(&values[0]), BufUsage_Static.ToGL())
+	}
+
+	gl.BindVertexArray(0)
+	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, 0)
+}
+
+func (b *Buffer) GetLayout() []Element {
+	e := make([]Element, len(b.layout))
+	copy(e, b.layout)
+	return e
+}
+
+//SetLayout updates the layout object and the corresponding vertex attributes.
+//Vertex attributes are also enabled.
+func (b *Buffer) SetLayout(layout ...Element) {
+
+	b.layout = layout
+
+	b.Stride = 0
+	for i := 0; i < len(b.layout); i++ {
+
+		b.layout[i].Offset = int(b.Stride)
+		b.Stride += b.layout[i].Size()
+	}
+
+	//Set opengl stuff
+	b.Bind()
+
+	//NOTE: VBOs are only bound at 'VertexAttribPointer', not BindBUffer, so we need to bind the buffer and vao here
+	gl.BindBuffer(gl.ARRAY_BUFFER, b.BufID)
+
+	for i := 0; i < len(layout); i++ {
+		gl.EnableVertexAttribArray(uint32(i))
+		gl.VertexAttribPointer(uint32(i), layout[i].ElementType.CompCount(), layout[i].ElementType.GLType(), false, b.Stride, gl.PtrOffset(layout[i].Offset))
+	}
+
+	b.UnBind()
+	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
+}
+
+func NewBuffer(layout ...Element) Buffer {
+
+	b := Buffer{}
+	gl.GenVertexArrays(1, &b.VAOID)
+	if b.VAOID == 0 {
 		logging.ErrLog.Println("Failed to create openGL vertex array object")
 	}
 
-	return &BufferObject{VAOID: vaoID}
+	gl.GenBuffers(1, &b.BufID)
+	if b.BufID == 0 {
+		logging.ErrLog.Println("Failed to create openGL buffer")
+	}
+
+	gl.GenBuffers(1, &b.IndexBufID)
+	if b.IndexBufID == 0 {
+		logging.ErrLog.Println("Failed to create openGL buffer")
+	}
+
+	b.SetLayout(layout...)
+	return b
 }

buffers/dataType.go

@@ -1,92 +0,0 @@
-package buffers
-
-import (
-	"github.com/bloeys/nmage/logging"
-	"github.com/go-gl/gl/v4.1-core/gl"
-)
-
-type DataType int
-
-const (
-	DataTypeUnknown DataType = iota
-	DataTypeUint32
-	DataTypeInt32
-	DataTypeFloat32
-	DataTypeFloat64
-
-	DataTypeVec2
-	DataTypeVec3
-	DataTypeVec4
-)
-
-type DataTypeInfo struct {
-	//ElementSize is size in bytes of one element (e.g. for vec3 its 4)
-	ElementSize int32
-	//ElementCount is number of elements (e.g. for vec3 its 3)
-	ElementCount int32
-	//ElementType is the type of each primitive (e.g. for vec3 its gl.FLOAT)
-	ElementType uint32
-	//GLType is the type of the variable represented (e.g. for vec3 its gl.FLOAT_VEC2)
-	GLType uint32
-}
-
-//GetSize returns the total size in bytes (e.g. for vec3 its 4*3)
-func (dti *DataTypeInfo) GetSize() int32 {
-	return dti.ElementSize * dti.ElementCount
-}
-
-func GetDataTypeInfo(dt DataType) DataTypeInfo {
-
-	switch dt {
-	case DataTypeUint32:
-		fallthrough
-	case DataTypeInt32:
-		return DataTypeInfo{
-			ElementSize:  4,
-			ElementCount: 1,
-			ElementType:  gl.INT,
-			GLType:       gl.INT,
-		}
-
-	case DataTypeFloat32:
-		return DataTypeInfo{
-			ElementSize:  4,
-			ElementCount: 1,
-			ElementType:  gl.FLOAT,
-			GLType:       gl.FLOAT,
-		}
-	case DataTypeFloat64:
-		return DataTypeInfo{
-			ElementSize:  8,
-			ElementCount: 1,
-			ElementType:  gl.DOUBLE,
-			GLType:       gl.DOUBLE,
-		}
-
-	case DataTypeVec2:
-		return DataTypeInfo{
-			ElementSize:  4,
-			ElementCount: 2,
-			ElementType:  gl.FLOAT,
-			GLType:       gl.FLOAT_VEC2,
-		}
-	case DataTypeVec3:
-		return DataTypeInfo{
-			ElementSize:  4,
-			ElementCount: 3,
-			ElementType:  gl.FLOAT,
-			GLType:       gl.FLOAT_VEC3,
-		}
-	case DataTypeVec4:
-		return DataTypeInfo{
-			ElementSize:  4,
-			ElementCount: 4,
-			ElementType:  gl.FLOAT,
-			GLType:       gl.FLOAT_VEC4,
-		}
-
-	default:
-		logging.WarnLog.Println("Unknown data type passed. DataType:", dt)
-		return DataTypeInfo{}
-	}
-}

buffers/element.go

@@ -0,0 +1,122 @@
+package buffers
+
+import (
+	"fmt"
+
+	"github.com/bloeys/nmage/assert"
+	"github.com/go-gl/gl/v4.1-core/gl"
+)
+
+//Element represents an element that makes up a buffer (e.g. Vec3 at an offset of 12 bytes)
+type Element struct {
+	Offset int
+	ElementType
+}
+
+//ElementType is the type of an element thats makes up a buffer (e.g. Vec3)
+type ElementType int
+
+const (
+	DataTypeUnknown ElementType = iota
+	DataTypeUint32
+	DataTypeInt32
+	DataTypeFloat32
+
+	DataTypeVec2
+	DataTypeVec3
+	DataTypeVec4
+)
+
+func (dt ElementType) GLType() uint32 {
+
+	switch dt {
+	case DataTypeUint32:
+		return gl.UNSIGNED_INT
+	case DataTypeInt32:
+		return gl.INT
+
+	case DataTypeFloat32:
+		fallthrough
+	case DataTypeVec2:
+		fallthrough
+	case DataTypeVec3:
+		fallthrough
+	case DataTypeVec4:
+		return gl.FLOAT
+
+	default:
+		assert.T(false, fmt.Sprintf("Unknown data type passed. DataType '%v'", dt))
+		return 0
+	}
+}
+
+//CompSize returns the size in bytes for one component of the type (e.g. for Vec2 its 4)
+func (dt ElementType) CompSize() int32 {
+
+	switch dt {
+	case DataTypeUint32:
+		fallthrough
+	case DataTypeFloat32:
+		fallthrough
+	case DataTypeInt32:
+		fallthrough
+	case DataTypeVec2:
+		fallthrough
+	case DataTypeVec3:
+		fallthrough
+	case DataTypeVec4:
+		return 4
+
+	default:
+		assert.T(false, fmt.Sprintf("Unknown data type passed. DataType '%v'", dt))
+		return 0
+	}
+}
+
+//CompCount returns the number of components in the element (e.g. for Vec2 its 2)
+func (dt ElementType) CompCount() int32 {
+
+	switch dt {
+	case DataTypeUint32:
+		fallthrough
+	case DataTypeFloat32:
+		fallthrough
+	case DataTypeInt32:
+		return 1
+
+	case DataTypeVec2:
+		return 2
+	case DataTypeVec3:
+		return 3
+	case DataTypeVec4:
+		return 4
+
+	default:
+		assert.T(false, fmt.Sprintf("Unknown data type passed. DataType '%v'", dt))
+		return 0
+	}
+}
+
+//Size returns the total size in bytes (e.g. for vec3 its 3*4=12 bytes)
+func (dt ElementType) Size() int32 {
+
+	switch dt {
+	case DataTypeUint32:
+		fallthrough
+	case DataTypeFloat32:
+		fallthrough
+	case DataTypeInt32:
+		return 4
+
+	case DataTypeVec2:
+		return 2 * 4
+	case DataTypeVec3:
+		return 3 * 4
+	case DataTypeVec4:
+		return 4 * 4
+
+	default:
+		assert.T(false, fmt.Sprintf("Unknown data type passed. DataType '%v'", dt))
+		return 0
+	}
+}

camera/camera.go

@@ -0,0 +1,100 @@
+package camera
+
+import (
+	"github.com/bloeys/gglm/gglm"
+)
+
+type Type int32
+
+const (
+	Type_Unknown Type = iota
+	Type_Perspective
+	Type_Orthographic
+)
+
+type Camera struct {
+	Type Type
+
+	Pos     gglm.Vec3
+	Forward gglm.Vec3
+	WorldUp gglm.Vec3
+
+	NearClip float32
+	FarClip  float32
+
+	// Perspective data
+	Fov         float32
+	AspectRatio float32
+
+	// Ortho data
+	Left, Right, Top, Bottom float32
+
+	// Matrices
+	ViewMat gglm.Mat4
+	ProjMat gglm.Mat4
+}
+
+// Update recalculates view matrix and projection matrix.
+// Should be called whenever a camera parameter changes
+func (c *Camera) Update() {
+
+	c.ViewMat = gglm.LookAtRH(&c.Pos, c.Pos.Clone().Add(&c.Forward), &c.WorldUp).Mat4
+
+	if c.Type == Type_Perspective {
+		c.ProjMat = *gglm.Perspective(c.Fov, c.AspectRatio, c.NearClip, c.FarClip)
+	} else {
+		c.ProjMat = gglm.Ortho(c.Left, c.Right, c.Top, c.Bottom, c.NearClip, c.FarClip).Mat4
+	}
+}
+
+// UpdateRotation calculates a new forward vector and then calls camera.Update()
+func (c *Camera) UpdateRotation(pitch, yaw float32) {
+
+	dir := gglm.NewVec3(
+		gglm.Cos32(yaw)*gglm.Cos32(pitch),
+		gglm.Sin32(pitch),
+		gglm.Sin32(yaw)*gglm.Cos32(pitch),
+	)
+	c.Forward = *dir.Normalize()
+	c.Update()
+}
+
+func NewPerspective(pos, forward, worldUp *gglm.Vec3, nearClip, farClip, fovRadians, aspectRatio float32) *Camera {
+
+	cam := &Camera{
+		Type:    Type_Perspective,
+		Pos:     *pos,
+		Forward: *forward,
+		WorldUp: *worldUp,
+
+		NearClip: nearClip,
+		FarClip:  farClip,
+
+		Fov:         fovRadians,
+		AspectRatio: aspectRatio,
+	}
+	cam.Update()
+
+	return cam
+}
+
+func NewOrthographic(pos, forward, worldUp *gglm.Vec3, nearClip, farClip, left, right, top, bottom float32) *Camera {
+
+	cam := &Camera{
+		Type:    Type_Orthographic,
+		Pos:     *pos,
+		Forward: *forward,
+		WorldUp: *worldUp,
+
+		NearClip: nearClip,
+		FarClip:  farClip,
+
+		Left:   left,
+		Right:  right,
+		Top:    top,
+		Bottom: bottom,
+	}
+	cam.Update()
+
+	return cam
+}

consts/flags_debug.go

@@ -1,4 +1,4 @@
-//go:build debug
+//go:build !release
 
 package consts
 

consts/flags_release.go

@@ -1,4 +1,4 @@
-//go:build !debug
+//go:build release
 
 package consts
 

engine/engine.go

@@ -0,0 +1,204 @@
+package engine
+
+import (
+	"runtime"
+
+	"github.com/bloeys/nmage/assert"
+	"github.com/bloeys/nmage/input"
+	"github.com/bloeys/nmage/renderer"
+	"github.com/bloeys/nmage/timing"
+	"github.com/go-gl/gl/v4.1-core/gl"
+	"github.com/inkyblackness/imgui-go/v4"
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+var (
+	isInited = false
+)
+
+type Window struct {
+	SDLWin         *sdl.Window
+	GlCtx          sdl.GLContext
+	EventCallbacks []func(sdl.Event)
+	Rend           renderer.Render
+}
+
+func (w *Window) handleInputs() {
+
+	input.EventLoopStart()
+	imIO := imgui.CurrentIO()
+
+	for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
+
+		//Fire callbacks
+		for i := 0; i < len(w.EventCallbacks); i++ {
+			w.EventCallbacks[i](event)
+		}
+
+		//Internal processing
+		switch e := event.(type) {
+
+		case *sdl.MouseWheelEvent:
+
+			input.HandleMouseWheelEvent(e)
+
+			xDelta, yDelta := input.GetMouseWheelMotion()
+			imIO.AddMouseWheelDelta(float32(xDelta), float32(yDelta))
+
+		case *sdl.KeyboardEvent:
+			input.HandleKeyboardEvent(e)
+
+			if e.Type == sdl.KEYDOWN {
+				imIO.KeyPress(int(e.Keysym.Scancode))
+			} else if e.Type == sdl.KEYUP {
+				imIO.KeyRelease(int(e.Keysym.Scancode))
+			}
+
+		case *sdl.TextInputEvent:
+			imIO.AddInputCharacters(string(e.Text[:]))
+
+		case *sdl.MouseButtonEvent:
+			input.HandleMouseBtnEvent(e)
+
+		case *sdl.MouseMotionEvent:
+			input.HandleMouseMotionEvent(e)
+
+		case *sdl.WindowEvent:
+			if e.Event == sdl.WINDOWEVENT_SIZE_CHANGED {
+				w.handleWindowResize()
+			}
+
+		case *sdl.QuitEvent:
+			input.HandleQuitEvent(e)
+		}
+	}
+
+	// If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
+	x, y, _ := sdl.GetMouseState()
+	imIO.SetMousePosition(imgui.Vec2{X: float32(x), Y: float32(y)})
+
+	imIO.SetMouseButtonDown(0, input.MouseDown(sdl.BUTTON_LEFT))
+	imIO.SetMouseButtonDown(1, input.MouseDown(sdl.BUTTON_RIGHT))
+	imIO.SetMouseButtonDown(2, input.MouseDown(sdl.BUTTON_MIDDLE))
+
+	imIO.KeyShift(sdl.SCANCODE_LSHIFT, sdl.SCANCODE_RSHIFT)
+	imIO.KeyCtrl(sdl.SCANCODE_LCTRL, sdl.SCANCODE_RCTRL)
+	imIO.KeyAlt(sdl.SCANCODE_LALT, sdl.SCANCODE_RALT)
+}
+
+func (w *Window) handleWindowResize() {
+
+	fbWidth, fbHeight := w.SDLWin.GLGetDrawableSize()
+	if fbWidth <= 0 || fbHeight <= 0 {
+		return
+	}
+	gl.Viewport(0, 0, fbWidth, fbHeight)
+}
+
+func (w *Window) Destroy() error {
+	return w.SDLWin.Destroy()
+}
+
+func Init() error {
+
+	isInited = true
+
+	runtime.LockOSThread()
+	timing.Init()
+	err := initSDL()
+
+	return err
+}
+
+func initSDL() error {
+
+	err := sdl.Init(sdl.INIT_EVERYTHING)
+	if err != nil {
+		return err
+	}
+
+	sdl.ShowCursor(1)
+
+	sdl.GLSetAttribute(sdl.MAJOR_VERSION, 4)
+	sdl.GLSetAttribute(sdl.MINOR_VERSION, 1)
+
+	// R(0-255) G(0-255) B(0-255)
+	sdl.GLSetAttribute(sdl.GL_RED_SIZE, 8)
+	sdl.GLSetAttribute(sdl.GL_GREEN_SIZE, 8)
+	sdl.GLSetAttribute(sdl.GL_BLUE_SIZE, 8)
+
+	sdl.GLSetAttribute(sdl.GL_DOUBLEBUFFER, 1)
+	sdl.GLSetAttribute(sdl.GL_DEPTH_SIZE, 24)
+	sdl.GLSetAttribute(sdl.GL_STENCIL_SIZE, 8)
+
+	sdl.GLSetAttribute(sdl.GL_CONTEXT_PROFILE_MASK, sdl.GL_CONTEXT_PROFILE_CORE)
+
+	return nil
+}
+
+func CreateOpenGLWindow(title string, x, y, width, height int32, flags WindowFlags, rend renderer.Render) (*Window, error) {
+	return createWindow(title, x, y, width, height, WindowFlags_OPENGL|flags, rend)
+}
+
+func CreateOpenGLWindowCentered(title string, width, height int32, flags WindowFlags, rend renderer.Render) (*Window, error) {
+	return createWindow(title, -1, -1, width, height, WindowFlags_OPENGL|flags, rend)
+}
+
+func createWindow(title string, x, y, width, height int32, flags WindowFlags, rend renderer.Render) (*Window, error) {
+
+	assert.T(isInited, "engine.Init was not called!")
+	if x == -1 && y == -1 {
+		x = sdl.WINDOWPOS_CENTERED
+		y = sdl.WINDOWPOS_CENTERED
+	}
+
+	sdlWin, err := sdl.CreateWindow(title, x, y, width, height, uint32(flags))
+	if err != nil {
+		return nil, err
+	}
+	win := &Window{
+		SDLWin:         sdlWin,
+		EventCallbacks: make([]func(sdl.Event), 0),
+		Rend:           rend,
+	}
+
+	win.GlCtx, err = sdlWin.GLCreateContext()
+	if err != nil {
+		return nil, err
+	}
+
+	err = initOpenGL()
+	if err != nil {
+		return nil, err
+	}
+
+	return win, err
+}
+
+func initOpenGL() error {
+
+	if err := gl.Init(); err != nil {
+		return err
+	}
+
+	gl.Enable(gl.DEPTH_TEST)
+	gl.Enable(gl.CULL_FACE)
+	gl.CullFace(gl.BACK)
+	gl.FrontFace(gl.CCW)
+
+	gl.Enable(gl.BLEND)
+	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
+
+	gl.ClearColor(0, 0, 0, 1)
+	return nil
+}
+
+func SetVSync(enabled bool) {
+	assert.T(isInited, "engine.Init was not called!")
+
+	if enabled {
+		sdl.GLSetSwapInterval(1)
+	} else {
+		sdl.GLSetSwapInterval(0)
+	}
+}

engine/game.go

@@ -0,0 +1,61 @@
+package engine
+
+import (
+	"github.com/bloeys/nmage/timing"
+	nmageimgui "github.com/bloeys/nmage/ui/imgui"
+	"github.com/go-gl/gl/v4.1-core/gl"
+)
+
+var (
+	isRunning = false
+)
+
+type Game interface {
+	Init()
+
+	Update()
+	Render()
+	FrameEnd()
+
+	DeInit()
+}
+
+func Run(g Game, w *Window, ui nmageimgui.ImguiInfo) {
+
+	isRunning = true
+	g.Init()
+
+	//Simulate an imgui frame during init so any imgui calls are allowed within init
+	tempWidth, tempHeight := w.SDLWin.GetSize()
+	tempFBWidth, tempFBHeight := w.SDLWin.GLGetDrawableSize()
+	ui.FrameStart(float32(tempWidth), float32(tempHeight))
+	ui.Render(float32(tempWidth), float32(tempHeight), tempFBWidth, tempFBHeight)
+
+	for isRunning {
+
+		//PERF: Cache these
+		width, height := w.SDLWin.GetSize()
+		fbWidth, fbHeight := w.SDLWin.GLGetDrawableSize()
+
+		timing.FrameStarted()
+		w.handleInputs()
+		ui.FrameStart(float32(width), float32(height))
+
+		g.Update()
+
+		gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
+		g.Render()
+		ui.Render(float32(width), float32(height), fbWidth, fbHeight)
+		w.SDLWin.GLSwap()
+
+		g.FrameEnd()
+		w.Rend.FrameEnd()
+		timing.FrameEnded()
+	}
+
+	g.DeInit()
+}
+
+func Quit() {
+	isRunning = false
+}

engine/windowflags.go

@@ -0,0 +1,29 @@
+package engine
+
+import "github.com/veandco/go-sdl2/sdl"
+
+type WindowFlags int
+
+const (
+	WindowFlags_FULLSCREEN         WindowFlags = sdl.WINDOW_FULLSCREEN
+	WindowFlags_OPENGL             WindowFlags = sdl.WINDOW_OPENGL
+	WindowFlags_SHOWN              WindowFlags = sdl.WINDOW_SHOWN
+	WindowFlags_HIDDEN             WindowFlags = sdl.WINDOW_HIDDEN
+	WindowFlags_BORDERLESS         WindowFlags = sdl.WINDOW_BORDERLESS
+	WindowFlags_RESIZABLE          WindowFlags = sdl.WINDOW_RESIZABLE
+	WindowFlags_MINIMIZED          WindowFlags = sdl.WINDOW_MINIMIZED
+	WindowFlags_MAXIMIZED          WindowFlags = sdl.WINDOW_MAXIMIZED
+	WindowFlags_INPUT_GRABBED      WindowFlags = sdl.WINDOW_INPUT_GRABBED
+	WindowFlags_INPUT_FOCUS        WindowFlags = sdl.WINDOW_INPUT_FOCUS
+	WindowFlags_MOUSE_FOCUS        WindowFlags = sdl.WINDOW_MOUSE_FOCUS
+	WindowFlags_FULLSCREEN_DESKTOP WindowFlags = sdl.WINDOW_FULLSCREEN_DESKTOP
+	WindowFlags_FOREIGN            WindowFlags = sdl.WINDOW_FOREIGN
+	WindowFlags_ALLOW_HIGHDPI      WindowFlags = sdl.WINDOW_ALLOW_HIGHDPI
+	WindowFlags_MOUSE_CAPTURE      WindowFlags = sdl.WINDOW_MOUSE_CAPTURE
+	WindowFlags_ALWAYS_ON_TOP      WindowFlags = sdl.WINDOW_ALWAYS_ON_TOP
+	WindowFlags_SKIP_TASKBAR       WindowFlags = sdl.WINDOW_SKIP_TASKBAR
+	WindowFlags_UTILITY            WindowFlags = sdl.WINDOW_UTILITY
+	WindowFlags_TOOLTIP            WindowFlags = sdl.WINDOW_TOOLTIP
+	WindowFlags_POPUP_MENU         WindowFlags = sdl.WINDOW_POPUP_MENU
+	// WindowFlags_VULKAN             WindowFlags = sdl.WINDOW_VULKAN
+)

entity/entity.go

@@ -0,0 +1,77 @@
+package entity
+
+type EntityFlag byte
+
+const (
+	EntityFlag_Unknown EntityFlag = 0
+	EntityFlag_Dead    EntityFlag = 1 << (iota - 1)
+	EntityFlag_Alive
+)
+
+const (
+	GenerationShiftBits = 64 - 8
+	FlagsShiftBits      = 64 - 16
+	IndexBitMask        = 0x00_00_FFFF_FFFF_FFFF
+)
+
+type Entity struct {
+
+	// Byte 1: Generation; Byte 2: Flags; Bytes 3-8: Index
+	ID    uint64
+	Comps []Comp
+}
+
+func GetGeneration(id uint64) byte {
+	return byte(id >> GenerationShiftBits)
+}
+
+func GetFlags(id uint64) byte {
+	return byte(id >> FlagsShiftBits)
+}
+
+func GetIndex(id uint64) uint64 {
+	return id & IndexBitMask
+}
+
+func (e *Entity) HasFlag(ef EntityFlag) bool {
+	return GetFlags(e.ID)&byte(ef) > 0
+}
+
+func NewEntityId(generation, flags byte, index uint64) uint64 {
+	return index | (uint64(generation) << GenerationShiftBits) | (uint64(flags) << FlagsShiftBits)
+}
+
+type Comp interface {
+	Name() string
+}
+
+func AddComp(e *Entity, c Comp) {
+	e.Comps = append(e.Comps, c)
+}
+
+func GetComp[T Comp](e *Entity) (out T) {
+
+	for i := 0; i < len(e.Comps); i++ {
+
+		comp, ok := e.Comps[i].(T)
+		if ok {
+			return comp
+		}
+	}
+
+	return out
+}
+
+func GetAllCompOfType[T Comp](e *Entity) (out []T) {
+
+	out = []T{}
+	for i := 0; i < len(e.Comps); i++ {
+
+		comp, ok := e.Comps[i].(T)
+		if ok {
+			out = append(out, comp)
+		}
+	}
+
+	return out
+}

entity/registry.go

@@ -0,0 +1,94 @@
+package entity
+
+import (
+	"github.com/bloeys/nmage/assert"
+)
+
+type freeListitem struct {
+	EntityIndex uint64
+	nextFree    *freeListitem
+}
+
+type Registry struct {
+	EntityCount uint64
+	Entities    []Entity
+	FreeList    *freeListitem
+}
+
+func (r *Registry) NewEntity() *Entity {
+
+	assert.T(r.EntityCount < uint64(len(r.Entities)), "Can not add more entities to registry because it is full")
+
+	entityToUseIndex := uint64(0)
+	var entityToUse *Entity = nil
+
+	if r.FreeList != nil {
+
+		entityToUseIndex = r.FreeList.EntityIndex
+		entityToUse = &r.Entities[entityToUseIndex]
+		r.FreeList = r.FreeList.nextFree
+	} else {
+
+		for i := 0; i < len(r.Entities); i++ {
+
+			e := &r.Entities[i]
+			if GetFlags(e.ID) != byte(EntityFlag_Unknown) && !e.HasFlag(EntityFlag_Dead) {
+				continue
+			}
+
+			entityToUse = e
+			entityToUseIndex = uint64(i)
+			break
+		}
+	}
+
+	if entityToUse == nil {
+		panic("failed to create new entity because we did not find a free spot in the registry. Why did the assert not go off?")
+	}
+
+	r.EntityCount++
+	entityToUse.ID = NewEntityId(GetGeneration(entityToUse.ID)+1, byte(EntityFlag_Alive), entityToUseIndex)
+	assert.T(entityToUse.ID != 0, "Entity ID must not be zero")
+	return entityToUse
+}
+
+func (r *Registry) GetEntity(id uint64) *Entity {
+
+	index := GetIndex(id)
+	gen := GetGeneration(id)
+
+	e := &r.Entities[index]
+	eGen := GetGeneration(e.ID)
+
+	if gen != eGen {
+		return nil
+	}
+
+	return e
+}
+
+func (r *Registry) FreeEntity(id uint64) {
+
+	e := r.GetEntity(id)
+	if e == nil {
+		return
+	}
+
+	r.EntityCount--
+	eIndex := GetIndex(e.ID)
+
+	e.Comps = []Comp{}
+	e.ID = NewEntityId(GetGeneration(e.ID), byte(EntityFlag_Dead), eIndex)
+
+	r.FreeList = &freeListitem{
+		EntityIndex: eIndex,
+		nextFree:    r.FreeList,
+	}
+}
+
+func NewRegistry(size uint32) *Registry {
+	assert.T(size > 0, "Registry size must be more than zero")
+	return &Registry{
+		Entities: make([]Entity, size),
+	}
+}

go.mod

@@ -1,13 +1,13 @@
 module github.com/bloeys/nmage
 
-go 1.17
+go 1.18
 
-require github.com/veandco/go-sdl2 v0.4.10
+require github.com/veandco/go-sdl2 v0.4.25
 
-require github.com/go-gl/gl v0.0.0-20211025173605-bda47ffaa784
+require github.com/go-gl/gl v0.0.0-20211210172815-726fda9656d6
 
 require (
-	github.com/bloeys/assimp-go v0.3.2
-	github.com/bloeys/gglm v0.3.1
-	github.com/inkyblackness/imgui-go/v4 v4.3.0
+	github.com/bloeys/assimp-go v0.4.2
+	github.com/bloeys/gglm v0.42.0
+	github.com/inkyblackness/imgui-go/v4 v4.6.0
 )

go.sum

@@ -1,19 +1,17 @@
-github.com/bloeys/assimp-go v0.3.1 h1:GANPXH8ER/4B/XsxZOw03GLZi2qKiWapSJ9dntrGoic=
-github.com/bloeys/assimp-go v0.3.1/go.mod h1:my3yRxT7CfOztmvi+0svmwbaqw0KFrxaHxncoyaEIP0=
-github.com/bloeys/assimp-go v0.3.2 h1:CsKnLloWZyn6uYNNaQE2Jq2Q+yH4d71A+CxbpU2flng=
-github.com/bloeys/assimp-go v0.3.2/go.mod h1:my3yRxT7CfOztmvi+0svmwbaqw0KFrxaHxncoyaEIP0=
-github.com/bloeys/gglm v0.3.1 h1:Sy9upW7SBsBfDXrSmEhid3aQ+7J7itej+upwcxOnPMQ=
-github.com/bloeys/gglm v0.3.1/go.mod h1:qwJQ0WzV191wAMwlGicbfbChbKoSedMk7gFFX6GnyOk=
+github.com/bloeys/assimp-go v0.4.2 h1:ArVK74BCFcTO/rCGj2NgZG9xtbjnJdEn5npIeJx1Z04=
+github.com/bloeys/assimp-go v0.4.2/go.mod h1:my3yRxT7CfOztmvi+0svmwbaqw0KFrxaHxncoyaEIP0=
+github.com/bloeys/gglm v0.42.0 h1:UAUFGTaZv3dpZ0YSIQVum3bdeCZgNmx965VLnD2v11k=
+github.com/bloeys/gglm v0.42.0/go.mod h1:qwJQ0WzV191wAMwlGicbfbChbKoSedMk7gFFX6GnyOk=
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/go-gl/gl v0.0.0-20211025173605-bda47ffaa784 h1:1Zi56D0LNfvkzM+BdoxKryvUEdyWO7LP8oRT+oSYJW0=
-github.com/go-gl/gl v0.0.0-20211025173605-bda47ffaa784/go.mod h1:9YTyiznxEY1fVinfM7RvRcjRHbw2xLBJ3AAGIT0I4Nw=
-github.com/inkyblackness/imgui-go/v4 v4.3.0 h1:iyAzqWXq/dG5+6ckDPhGivtrIo6AywGQMvENKzun04s=
-github.com/inkyblackness/imgui-go/v4 v4.3.0/go.mod h1:g8SAGtOYUP7rYaOB2AsVKCEHmPMDmJKgt4z6d+flhb0=
+github.com/go-gl/gl v0.0.0-20211210172815-726fda9656d6 h1:zDw5v7qm4yH7N8C8uWd+8Ii9rROdgWxQuGoJ9WDXxfk=
+github.com/go-gl/gl v0.0.0-20211210172815-726fda9656d6/go.mod h1:9YTyiznxEY1fVinfM7RvRcjRHbw2xLBJ3AAGIT0I4Nw=
+github.com/inkyblackness/imgui-go/v4 v4.6.0 h1:ShcnXEYl80+xREGBY9OpGWePA6FfJChY9Varsm+3jjE=
+github.com/inkyblackness/imgui-go/v4 v4.6.0/go.mod h1:g8SAGtOYUP7rYaOB2AsVKCEHmPMDmJKgt4z6d+flhb0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.3.0 h1:TivCn/peBQ7UY8ooIcPgZFpTNSz0Q2U6UrFlUfqbe0Q=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
-github.com/veandco/go-sdl2 v0.4.10 h1:8QoD2bhWl7SbQDflIAUYWfl9Vq+mT8/boJFAUzAScgY=
-github.com/veandco/go-sdl2 v0.4.10/go.mod h1:OROqMhHD43nT4/i9crJukyVecjPNYYuCofep6SNiAjY=
+github.com/veandco/go-sdl2 v0.4.25 h1:J5ac3KKOccp/0xGJA1PaNYKPUcZm19IxhDGs8lJofPI=
+github.com/veandco/go-sdl2 v0.4.25/go.mod h1:OROqMhHD43nT4/i9crJukyVecjPNYYuCofep6SNiAjY=

input/input.go

@@ -35,6 +35,7 @@ var (
 	mouseBtnMap   = make(map[int]*mouseBtnState)
 	mouseMotion   = mouseMotionState{}
 	mouseWheel    = mouseWheelState{}
+	quitRequested bool
 )
 
 func EventLoopStart() {
@@ -55,6 +56,16 @@ func EventLoopStart() {
 
 	mouseWheel.XDelta = 0
 	mouseWheel.YDelta = 0
+
+	quitRequested = false
+}
+
+func HandleQuitEvent(e *sdl.QuitEvent) {
+	quitRequested = true
+}
+
+func IsQuitClicked() bool {
+	return quitRequested
 }
 
 func HandleKeyboardEvent(e *sdl.KeyboardEvent) {

level/level.go

@@ -0,0 +1,20 @@
+package level
+
+import (
+	"github.com/bloeys/nmage/assert"
+	"github.com/bloeys/nmage/entity"
+)
+
+type Level struct {
+	*entity.Registry
+	Name string
+}
+
+func NewLevel(name string, maxEntities uint32) *Level {
+
+	assert.T(name != "", "Level name can not be empty")
+	return &Level{
+		Name:     name,
+		Registry: entity.NewRegistry(maxEntities),
+	}
+}

main.go

@@ -2,622 +2,317 @@ package main
 
 import (
 	"fmt"
-	"runtime"
 
 	"github.com/bloeys/assimp-go/asig"
 	"github.com/bloeys/gglm/gglm"
-	"github.com/bloeys/nmage/asserts"
-	"github.com/bloeys/nmage/buffers"
+	"github.com/bloeys/nmage/assets"
+	"github.com/bloeys/nmage/camera"
+	"github.com/bloeys/nmage/engine"
+	"github.com/bloeys/nmage/entity"
 	"github.com/bloeys/nmage/input"
+	"github.com/bloeys/nmage/level"
 	"github.com/bloeys/nmage/logging"
-	"github.com/bloeys/nmage/shaders"
+	"github.com/bloeys/nmage/materials"
+	"github.com/bloeys/nmage/meshes"
+	"github.com/bloeys/nmage/renderer/rend3dgl"
 	"github.com/bloeys/nmage/timing"
-	"github.com/go-gl/gl/v4.1-core/gl"
+	nmageimgui "github.com/bloeys/nmage/ui/imgui"
 	"github.com/inkyblackness/imgui-go/v4"
 	"github.com/veandco/go-sdl2/sdl"
 )
 
-//TODO:
-//Make a window/engine class
-//Mesh class
-//Object
-//Abstract UI
-//Textures
+// @Todo:
+// Complete entity registry (e.g. HasEntity, GetEntity, Generational Indices etc...)
+// Helper functions to update active entities
+
+// Integrate physx
+// Create VAO struct independent from VBO to support multi-VBO use cases (e.g. instancing)
+// Renderer batching
+// Scene graph
+// Separate engine loop from rendering loop? or leave it to the user?
+// Abstract keys enum away from sdl
 // Proper Asset loading
-//Rework buffers package
-//Interleaved or packed buffers (xyzxyzxyz OR xxxyyyzzz)
-//Audio
+// Frustum culling
+// Material system editor with fields automatically extracted from the shader
 
-type ImguiInfo struct {
-	imCtx *imgui.Context
-
-	vaoID      uint32
-	vboID      uint32
-	indexBufID uint32
-	texID      uint32
-}
+const (
+	camSpeed         = 15
+	mouseSensitivity = 0.5
+)
 
 var (
-	winWidth  int32 = 1280
-	winHeight int32 = 720
+	window *engine.Window
 
-	isRunning bool = true
-	window    *sdl.Window
+	pitch float32 = 0
+	yaw   float32 = -90
+	cam   *camera.Camera
 
-	simpleShader shaders.ShaderProgram
-	imShader     shaders.ShaderProgram
-	bo           *buffers.BufferObject
+	simpleMat *materials.Material
+	cubeMesh  *meshes.Mesh
 
-	modelMat = gglm.NewTrMatId()
-	projMat  = &gglm.Mat4{}
+	cubeModelMat = gglm.NewTrMatId()
 
-	imguiInfo *ImguiInfo
-
-	camPos     = gglm.NewVec3(0, 0, -10)
-	camForward = gglm.NewVec3(0, 0, 1)
+	lightPos1   = gglm.NewVec3(-2, 0, 2)
+	lightColor1 = gglm.NewVec3(1, 1, 1)
 )
 
+type OurGame struct {
+	Win       *engine.Window
+	ImGUIInfo nmageimgui.ImguiInfo
+}
+
+type TransformComp struct {
+	Pos   *gglm.Vec3
+	Rot   *gglm.Quat
+	Scale *gglm.Vec3
+}
+
+func (t TransformComp) Name() string {
+	return "Transform Component"
+}
+
+func Test() {
+
+	lvl := level.NewLevel("test level", 1000)
+	e1 := lvl.Registry.NewEntity()
+
+	trComp := entity.GetComp[*TransformComp](e1)
+	fmt.Println("Got comp 1:", trComp)
+
+	e1.Comps = append(e1.Comps, &TransformComp{
+		Pos:   gglm.NewVec3(0, 0, 0),
+		Rot:   gglm.NewQuatEulerXYZ(0, 0, 0),
+		Scale: gglm.NewVec3(0, 0, 0),
+	}, &TransformComp{
+		Pos:   gglm.NewVec3(0, 0, 0),
+		Rot:   gglm.NewQuatEulerXYZ(0, 0, 0),
+		Scale: gglm.NewVec3(1, 1, 1),
+	})
+
+	trComp = entity.GetComp[*TransformComp](e1)
+	fmt.Println("Got comp 2:", trComp)
+
+	trComps := entity.GetAllCompOfType[*TransformComp](e1)
+	fmt.Printf("Got comp 3: %+v, %+v\n", trComps[0], trComps[1])
+
+	fmt.Printf("Entity: %+v\n", e1)
+	fmt.Printf("Entity: %+v\n", lvl.Registry.NewEntity())
+	fmt.Printf("Entity: %+v\n", lvl.Registry.NewEntity())
+	fmt.Printf("Entity: %+v\n", lvl.Registry.NewEntity())
+}
+
 func main() {
 
-	runtime.LockOSThread()
+	// Test()
+	// return
 
-	err := initSDL()
+	//Init engine
+	err := engine.Init()
 	if err != nil {
-		logging.ErrLog.Fatalln("Failed to init SDL. Err:", err)
+		logging.ErrLog.Fatalln("Failed to init nMage. Err:", err)
 	}
 
-	window, err = sdl.CreateWindow("Go SDL Engine", sdl.WINDOWPOS_CENTERED, sdl.WINDOWPOS_CENTERED, winWidth, winHeight, sdl.WINDOW_OPENGL|sdl.WINDOW_RESIZABLE)
+	//Create window
+	window, err = engine.CreateOpenGLWindowCentered("nMage", 1280, 720, engine.WindowFlags_RESIZABLE, rend3dgl.NewRend3DGL())
 	if err != nil {
 		logging.ErrLog.Fatalln("Failed to create window. Err: ", err)
 	}
 	defer window.Destroy()
 
-	glCtx, err := window.GLCreateContext()
-	if err != nil {
-		logging.ErrLog.Fatalln("Failed to create OpenGL context. Err: ", err)
-	}
-	defer sdl.GLDeleteContext(glCtx)
+	engine.SetVSync(false)
 
-	err = initOpenGL()
-	if err != nil {
-		logging.ErrLog.Fatalln(err)
+	game := &OurGame{
+		Win:       window,
+		ImGUIInfo: nmageimgui.NewImGUI(),
+	}
+	window.EventCallbacks = append(window.EventCallbacks, game.handleWindowEvents)
+
+	engine.Run(game, window, game.ImGUIInfo)
 }
 
-	//Set vsync
-	sdl.GLSetSwapInterval(0)
+func (g *OurGame) handleWindowEvents(e sdl.Event) {
 
-	loadShaders()
-	loadBuffers()
-	initImGUI()
+	switch e := e.(type) {
+	case *sdl.WindowEvent:
+		if e.Event == sdl.WINDOWEVENT_SIZE_CHANGED {
 
-	//Enable vertex attributes
-	simpleShader.SetAttribute("vertPosIn", bo, bo.VertPosBuf)
-	simpleShader.EnableAttribute("vertPosIn")
+			width := e.Data1
+			height := e.Data2
+			cam.AspectRatio = float32(width) / float32(height)
+			cam.Update()
 
-	simpleShader.SetAttribute("vertColorIn", bo, bo.ColorBuf)
-	simpleShader.EnableAttribute("vertColorIn")
+			simpleMat.SetUnifMat4("projMat", &cam.ProjMat)
+		}
+	}
+}
 
-	simpleShader.SetAttribute("vertNormalIn", bo, bo.NormalBuf)
-	simpleShader.EnableAttribute("vertNormalIn")
+func (g *OurGame) Init() {
+
+	//Create materials
+	simpleMat = materials.NewMaterial("Simple Mat", "./res/shaders/simple.glsl")
+
+	//Load meshes
+	var err error
+	cubeMesh, err = meshes.NewMesh("Cube", "./res/models/tex-cube.fbx", asig.PostProcess(0))
+	if err != nil {
+		logging.ErrLog.Fatalln("Failed to load cube mesh. Err: ", err)
+	}
+
+	//Load textures
+	tex, err := assets.LoadTexturePNG("./res/textures/Low poly planet.png", nil)
+	if err != nil {
+		logging.ErrLog.Fatalln("Failed to load texture. Err: ", err)
+	}
+
+	//Configure material
+	simpleMat.DiffuseTex = tex.TexID
 
 	//Movement, scale and rotation
 	translationMat := gglm.NewTranslationMat(gglm.NewVec3(0, 0, 0))
 	scaleMat := gglm.NewScaleMat(gglm.NewVec3(0.25, 0.25, 0.25))
 	rotMat := gglm.NewRotMat(gglm.NewQuatEuler(gglm.NewVec3(0, 0, 0).AsRad()))
 
-	modelMat.Mul(translationMat.Mul(rotMat.Mul(scaleMat)))
-	simpleShader.SetUnifMat4("modelMat", &modelMat.Mat4)
+	cubeModelMat.Mul(translationMat.Mul(rotMat.Mul(scaleMat)))
+	simpleMat.SetUnifMat4("modelMat", &cubeModelMat.Mat4)
+
+	// Camera
+	winWidth, winHeight := g.Win.SDLWin.GetSize()
+	cam = camera.NewPerspective(
+		gglm.NewVec3(0, 0, 10),
+		gglm.NewVec3(0, 0, -1),
+		gglm.NewVec3(0, 1, 0),
+		0.1, 20,
+		45*gglm.Deg2Rad,
+		float32(winWidth)/float32(winHeight),
+	)
+	simpleMat.SetUnifMat4("projMat", &cam.ProjMat)
 
-	//Moves objects into the cameras view
 	updateViewMat()
 
-	//Perspective/Depth
-	projMat := gglm.Perspective(45*gglm.Deg2Rad, float32(winWidth)/float32(winHeight), 0.1, 500)
-	simpleShader.SetUnifMat4("projMat", projMat)
-
 	//Lights
-	simpleShader.SetUnifVec3("lightPos1", &lightPos1)
-	simpleShader.SetUnifVec3("lightColor1", &lightColor1)
-
-	//Game loop
-	timing.Init()
-	for isRunning {
-
-		timing.FrameStarted()
-
-		handleInputs()
-		runGameLogic()
-
-		draw()
-
-		timing.FrameEnded()
-
-		window.SetTitle(fmt.Sprintf("FPS: %.0f; Elapsed: %v", 1/timing.DT(), timing.ElapsedTime()))
+	simpleMat.SetUnifVec3("lightPos1", lightPos1)
+	simpleMat.SetUnifVec3("lightColor1", lightColor1)
 }
+
+// @TODO: Add this to gglm
+// func vecRotByQuat(v *gglm.Vec3, q *gglm.Quat) *gglm.Vec3 {
+
+// 	// Reference: https://gamedev.stackexchange.com/questions/28395/rotating-vector3-by-a-quaternion
+// 	qVec := gglm.NewVec3(q.X(), q.Y(), q.Z())
+
+// 	rotatedVec := qVec.Clone().Scale(2 * gglm.DotVec3(v, qVec))
+
+// 	t1 := q.W()*q.W() - gglm.DotVec3(qVec, qVec)
+// 	rotatedVec.Add(v.Clone().Scale(t1))
+
+// 	rotatedVec.Add(gglm.Cross(qVec, v).Scale(2 * q.W()))
+// 	return rotatedVec
+// }
+
+func (g *OurGame) Update() {
+
+	if input.IsQuitClicked() || input.KeyClicked(sdl.K_ESCAPE) {
+		engine.Quit()
+	}
+
+	g.updateCameraLookAround()
+	g.updateCameraPos()
+
+	//Rotating cubes
+	if input.KeyDown(sdl.K_SPACE) {
+		cubeModelMat.Rotate(10*timing.DT()*gglm.Deg2Rad, gglm.NewVec3(1, 1, 1).Normalize())
+		simpleMat.SetUnifMat4("modelMat", &cubeModelMat.Mat4)
+	}
+
+	if imgui.DragFloat3("Cam Pos", &cam.Pos.Data) {
+		updateViewMat()
+	}
+	if imgui.DragFloat3("Cam Forward", &cam.Forward.Data) {
+		updateViewMat()
+	}
+
+	if input.KeyClicked(sdl.K_F4) {
+		fmt.Printf("Pos: %s; Forward: %s; |Forward|: %f\n", cam.Pos.String(), cam.Forward.String(), cam.Forward.Mag())
+	}
+}
+
+func (g *OurGame) updateCameraLookAround() {
+
+	mouseX, mouseY := input.GetMouseMotion()
+	if mouseX == 0 && mouseY == 0 {
+		return
+	}
+
+	// Yaw
+	yaw += float32(mouseX) * mouseSensitivity * timing.DT()
+
+	// Pitch
+	pitch += float32(-mouseY) * mouseSensitivity * timing.DT()
+	if pitch > 89.0 {
+		pitch = 89.0
+	}
+
+	if pitch < -89.0 {
+		pitch = -89.0
+	}
+
+	// Update cam forward
+	cam.UpdateRotation(pitch, yaw)
+
+	updateViewMat()
+}
+
+func (g *OurGame) updateCameraPos() {
+
+	update := false
+
+	// Forward and backward
+	if input.KeyDown(sdl.K_w) {
+		cam.Pos.Add(cam.Forward.Clone().Scale(camSpeed * timing.DT()))
+		update = true
+	} else if input.KeyDown(sdl.K_s) {
+		cam.Pos.Add(cam.Forward.Clone().Scale(-camSpeed * timing.DT()))
+		update = true
+	}
+
+	// Left and right
+	if input.KeyDown(sdl.K_d) {
+		cam.Pos.Add(gglm.Cross(&cam.Forward, &cam.WorldUp).Normalize().Scale(camSpeed * timing.DT()))
+		update = true
+	} else if input.KeyDown(sdl.K_a) {
+		cam.Pos.Add(gglm.Cross(&cam.Forward, &cam.WorldUp).Normalize().Scale(-camSpeed * timing.DT()))
+		update = true
+	}
+
+	if update {
+		updateViewMat()
+	}
+}
+
+func (g *OurGame) Render() {
+
+	tempModelMat := cubeModelMat.Clone()
+
+	rowSize := 100
+	for y := 0; y < rowSize; y++ {
+		for x := 0; x < rowSize; x++ {
+			tempModelMat.Translate(gglm.NewVec3(-1, 0, 0))
+			window.Rend.Draw(cubeMesh, tempModelMat, simpleMat)
+		}
+		tempModelMat.Translate(gglm.NewVec3(float32(rowSize), -1, 0))
+	}
+
+	g.Win.SDLWin.SetTitle(fmt.Sprint("nMage (", timing.GetAvgFPS(), " fps)"))
+}
+
+func (g *OurGame) FrameEnd() {
+}
+
+func (g *OurGame) DeInit() {
+	g.Win.Destroy()
 }
 
 func updateViewMat() {
-	targetPos := camPos.Clone().Add(camForward)
-	viewMat := gglm.LookAt(camPos, targetPos, gglm.NewVec3(0, 1, 0))
-	simpleShader.SetUnifMat4("viewMat", &viewMat.Mat4)
-}
-
-func initSDL() error {
-
-	err := sdl.Init(sdl.INIT_EVERYTHING)
-	if err != nil {
-		return err
-	}
-
-	sdl.ShowCursor(1)
-
-	sdl.GLSetAttribute(sdl.MAJOR_VERSION, 4)
-	sdl.GLSetAttribute(sdl.MINOR_VERSION, 1)
-
-	// R(0-255) G(0-255) B(0-255)
-	sdl.GLSetAttribute(sdl.GL_RED_SIZE, 8)
-	sdl.GLSetAttribute(sdl.GL_GREEN_SIZE, 8)
-	sdl.GLSetAttribute(sdl.GL_BLUE_SIZE, 8)
-
-	sdl.GLSetAttribute(sdl.GL_DOUBLEBUFFER, 1)
-	sdl.GLSetAttribute(sdl.GL_DEPTH_SIZE, 24)
-	sdl.GLSetAttribute(sdl.GL_STENCIL_SIZE, 8)
-
-	sdl.GLSetAttribute(sdl.GL_CONTEXT_PROFILE_MASK, sdl.GL_CONTEXT_PROFILE_CORE)
-
-	return nil
-}
-
-func initOpenGL() error {
-
-	if err := gl.Init(); err != nil {
-		return err
-	}
-
-	gl.Enable(gl.DEPTH_TEST)
-
-	gl.Enable(gl.CULL_FACE)
-	gl.CullFace(gl.BACK)
-	gl.FrontFace(gl.CCW)
-
-	gl.ClearColor(0, 0, 0, 1)
-	return nil
-}
-
-func loadShaders() {
-
-	var err error
-	simpleShader, err = shaders.NewShaderProgram()
-	if err != nil {
-		logging.ErrLog.Fatalln("Failed to create new shader program. Err: ", err)
-	}
-
-	vertShader, err := shaders.LoadAndCompilerShader("./res/shaders/simple.vert.glsl", shaders.VertexShaderType)
-	if err != nil {
-		logging.ErrLog.Fatalln("Failed to create new shader. Err: ", err)
-	}
-
-	fragShader, err := shaders.LoadAndCompilerShader("./res/shaders/simple.frag.glsl", shaders.FragmentShaderType)
-	if err != nil {
-		logging.ErrLog.Fatalln("Failed to create new shader. Err: ", err)
-	}
-
-	simpleShader.AttachShader(vertShader)
-	simpleShader.AttachShader(fragShader)
-	simpleShader.Link()
-
-	//ImGUI shader
-	imShader, err = shaders.NewShaderProgram()
-	if err != nil {
-		logging.ErrLog.Fatalln("Failed to create new shader program. Err: ", err)
-	}
-
-	imguiVertShader, err := shaders.LoadAndCompilerShader("./res/shaders/imgui.vert.glsl", shaders.VertexShaderType)
-	if err != nil {
-		logging.ErrLog.Fatalln("Failed to create new shader. Err: ", err)
-	}
-
-	imguiFragShader, err := shaders.LoadAndCompilerShader("./res/shaders/imgui.frag.glsl", shaders.FragmentShaderType)
-	if err != nil {
-		logging.ErrLog.Fatalln("Failed to create new shader. Err: ", err)
-	}
-
-	imShader.AttachShader(imguiVertShader)
-	imShader.AttachShader(imguiFragShader)
-	imShader.Link()
-}
-
-func flattenVec3(vec3s []gglm.Vec3) []float32 {
-
-	floats := make([]float32, len(vec3s)*3)
-	for i := 0; i < len(vec3s); i++ {
-		floats[i*3+0] = vec3s[i].X()
-		floats[i*3+1] = vec3s[i].Y()
-		floats[i*3+2] = vec3s[i].Z()
-	}
-
-	return floats
-}
-
-func flattenVec4(vec4s []gglm.Vec4) []float32 {
-
-	floats := make([]float32, len(vec4s)*4)
-	for i := 0; i < len(vec4s); i++ {
-		floats[i*4+0] = vec4s[i].X()
-		floats[i*4+1] = vec4s[i].Y()
-		floats[i*4+2] = vec4s[i].Z()
-		floats[i*4+3] = vec4s[i].W()
-	}
-
-	return floats
-}
-
-func flattenFaces(faces []asig.Face) []uint32 {
-
-	asserts.True(len(faces[0].Indices) == 3, fmt.Sprintf("Face doesn't have 3 indices. Index count: %v\n", len(faces[0].Indices)))
-
-	uints := make([]uint32, len(faces)*3)
-	for i := 0; i < len(faces); i++ {
-		uints[i*3+0] = uint32(faces[i].Indices[0])
-		uints[i*3+1] = uint32(faces[i].Indices[1])
-		uints[i*3+2] = uint32(faces[i].Indices[2])
-	}
-
-	return uints
-}
-
-func loadBuffers() {
-
-	// scene, release, err := asig.ImportFile("./res/models/weird-cube.fbx", asig.PostProcessTriangulate)
-	scene, release, err := asig.ImportFile("./res/models/color-cube.fbx", asig.PostProcessTriangulate)
-	if err != nil {
-		logging.ErrLog.Panicln("Failed to load model. Err: " + err.Error())
-	}
-	release()
-
-	bo = buffers.NewBufferObject()
-	bo.GenBuffer(flattenVec3(scene.Meshes[0].Vertices), buffers.BufUsageStatic, buffers.BufTypeVertPos, buffers.DataTypeVec3)
-	bo.GenBuffer(flattenVec3(scene.Meshes[0].Normals), buffers.BufUsageStatic, buffers.BufTypeNormal, buffers.DataTypeVec3)
-	bo.GenBuffer(flattenVec4(scene.Meshes[0].ColorSets[0]), buffers.BufUsageStatic, buffers.BufTypeColor, buffers.DataTypeVec4)
-	bo.GenBufferUint32(flattenFaces(scene.Meshes[0].Faces), buffers.BufUsageStatic, buffers.BufTypeIndex, buffers.DataTypeUint32)
-}
-
-func initImGUI() {
-
-	imguiInfo = &ImguiInfo{
-		imCtx: imgui.CreateContext(nil),
-	}
-
-	imIO := imgui.CurrentIO()
-	imIO.SetBackendFlags(imIO.GetBackendFlags() | imgui.BackendFlagsRendererHasVtxOffset)
-
-	gl.GenVertexArrays(1, &imguiInfo.vaoID)
-	gl.GenBuffers(1, &imguiInfo.vboID)
-	gl.GenBuffers(1, &imguiInfo.indexBufID)
-	gl.GenTextures(1, &imguiInfo.texID)
-
-	// Upload font to gpu
-	gl.BindTexture(gl.TEXTURE_2D, imguiInfo.texID)
-	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
-	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
-	gl.PixelStorei(gl.UNPACK_ROW_LENGTH, 0)
-
-	image := imIO.Fonts().TextureDataAlpha8()
-	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RED, int32(image.Width), int32(image.Height), 0, gl.RED, gl.UNSIGNED_BYTE, image.Pixels)
-
-	// Store our identifier
-	imIO.Fonts().SetTextureID(imgui.TextureID(imguiInfo.texID))
-
-	//Shader attributes
-	imShader.Activate()
-	imShader.EnableAttribute("Position")
-	imShader.EnableAttribute("UV")
-	imShader.EnableAttribute("Color")
-	imShader.Deactivate()
-
-	//Init imgui input mapping
-	keys := map[int]int{
-		imgui.KeyTab:        sdl.SCANCODE_TAB,
-		imgui.KeyLeftArrow:  sdl.SCANCODE_LEFT,
-		imgui.KeyRightArrow: sdl.SCANCODE_RIGHT,
-		imgui.KeyUpArrow:    sdl.SCANCODE_UP,
-		imgui.KeyDownArrow:  sdl.SCANCODE_DOWN,
-		imgui.KeyPageUp:     sdl.SCANCODE_PAGEUP,
-		imgui.KeyPageDown:   sdl.SCANCODE_PAGEDOWN,
-		imgui.KeyHome:       sdl.SCANCODE_HOME,
-		imgui.KeyEnd:        sdl.SCANCODE_END,
-		imgui.KeyInsert:     sdl.SCANCODE_INSERT,
-		imgui.KeyDelete:     sdl.SCANCODE_DELETE,
-		imgui.KeyBackspace:  sdl.SCANCODE_BACKSPACE,
-		imgui.KeySpace:      sdl.SCANCODE_BACKSPACE,
-		imgui.KeyEnter:      sdl.SCANCODE_RETURN,
-		imgui.KeyEscape:     sdl.SCANCODE_ESCAPE,
-		imgui.KeyA:          sdl.SCANCODE_A,
-		imgui.KeyC:          sdl.SCANCODE_C,
-		imgui.KeyV:          sdl.SCANCODE_V,
-		imgui.KeyX:          sdl.SCANCODE_X,
-		imgui.KeyY:          sdl.SCANCODE_Y,
-		imgui.KeyZ:          sdl.SCANCODE_Z,
-	}
-
-	// Keyboard mapping. ImGui will use those indices to peek into the io.KeysDown[] array.
-	for imguiKey, nativeKey := range keys {
-		imIO.KeyMap(imguiKey, nativeKey)
-	}
-}
-
-func handleInputs() {
-
-	input.EventLoopStart()
-	imIO := imgui.CurrentIO()
-
-	for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
-
-		switch e := event.(type) {
-
-		case *sdl.MouseWheelEvent:
-
-			input.HandleMouseWheelEvent(e)
-
-			xDelta, yDelta := input.GetMouseWheelMotion()
-			imIO.AddMouseWheelDelta(float32(xDelta), float32(yDelta))
-
-		case *sdl.KeyboardEvent:
-			input.HandleKeyboardEvent(e)
-
-			if e.Type == sdl.KEYDOWN {
-				imIO.KeyPress(int(e.Keysym.Scancode))
-			} else if e.Type == sdl.KEYUP {
-				imIO.KeyRelease(int(e.Keysym.Scancode))
-			}
-
-		case *sdl.TextInputEvent:
-			imIO.AddInputCharacters(string(e.Text[:]))
-
-		case *sdl.MouseButtonEvent:
-			input.HandleMouseBtnEvent(e)
-
-		case *sdl.MouseMotionEvent:
-			input.HandleMouseMotionEvent(e)
-
-		case *sdl.WindowEvent:
-
-			//NOTE: SDL is not firing window resize, but is resizing the window by itself
-			// if e.Type != sdl.WINDOWEVENT_SIZE_CHANGED {
-			// 	continue
-			// }
-
-			// winWidth = e.Data1
-			// winHeight = e.Data2
-			// window.SetSize(int32(winWidth), int32(winHeight))
-
-			// projMat = gglm.Perspective(45*gglm.Deg2Rad, float32(winWidth)/float32(winHeight), 0.1, 20)
-			// simpleShader.SetUnifMat4("projMat", projMat)
-
-		case *sdl.QuitEvent:
-			isRunning = false
-		}
-	}
-
-	currWinWidth, currWinHeight := window.GetSize()
-	if winWidth != currWinWidth || winHeight != currWinHeight {
-		handleWindowResize(currWinWidth, currWinHeight)
-	}
-
-	// If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
-	x, y, _ := sdl.GetMouseState()
-	imIO.SetMousePosition(imgui.Vec2{X: float32(x), Y: float32(y)})
-
-	imIO.SetMouseButtonDown(0, input.MouseDown(sdl.BUTTON_LEFT))
-	imIO.SetMouseButtonDown(1, input.MouseDown(sdl.BUTTON_RIGHT))
-	imIO.SetMouseButtonDown(2, input.MouseDown(sdl.BUTTON_MIDDLE))
-
-	imIO.KeyShift(sdl.SCANCODE_LSHIFT, sdl.SCANCODE_RSHIFT)
-	imIO.KeyCtrl(sdl.SCANCODE_LCTRL, sdl.SCANCODE_RCTRL)
-	imIO.KeyAlt(sdl.SCANCODE_LALT, sdl.SCANCODE_RALT)
-}
-
-func handleWindowResize(newWinWidth, newWinHeight int32) {
-
-	winWidth = newWinWidth
-	winHeight = newWinHeight
-
-	fbWidth, fbHeight := window.GLGetDrawableSize()
-	if fbWidth <= 0 || fbHeight <= 0 {
-		return
-	}
-	gl.Viewport(0, 0, fbWidth, fbHeight)
-
-	projMat = gglm.Perspective(45*gglm.Deg2Rad, float32(winWidth)/float32(winHeight), 0.1, 20)
-	simpleShader.SetUnifMat4("projMat", projMat)
-}
-
-var time uint64 = 0
-var name string = ""
-
-var ambientColor gglm.Vec3 = *gglm.NewVec3(1, 1, 1)
-var ambientColorStrength float32 = 0.1
-
-var lightPos1 gglm.Vec3 = *gglm.NewVec3(2, 2, 0)
-var lightColor1 gglm.Vec3 = *gglm.NewVec3(1, 1, 1)
-
-func runGameLogic() {
-
-	if input.KeyDown(sdl.K_w) {
-		camPos.Data[1] += 0.1
-		updateViewMat()
-	}
-	if input.KeyDown(sdl.K_s) {
-		camPos.Data[1] -= 0.1
-		updateViewMat()
-	}
-	if input.KeyDown(sdl.K_d) {
-		camPos.Data[0] += 0.1
-		updateViewMat()
-	}
-	if input.KeyDown(sdl.K_a) {
-		camPos.Data[0] -= 0.1
-		updateViewMat()
-	}
-
-	if input.GetMouseWheelYNorm() > 0 {
-		camPos.Data[2] += 1
-		updateViewMat()
-	} else if input.GetMouseWheelYNorm() < 0 {
-		camPos.Data[2] -= 1
-		updateViewMat()
-	}
-
-	modelMat.Rotate(10*timing.DT()*gglm.Deg2Rad, gglm.NewVec3(1, 1, 1).Normalize())
-	simpleShader.SetUnifMat4("modelMat", &modelMat.Mat4)
-
-	//ImGUI
-	imIO := imgui.CurrentIO()
-	imIO.SetDisplaySize(imgui.Vec2{X: float32(winWidth), Y: float32(winHeight)})
-
-	// Setup time step (we don't use SDL_GetTicks() because it is using millisecond resolution)
-	frequency := sdl.GetPerformanceFrequency()
-	currentTime := sdl.GetPerformanceCounter()
-	if time > 0 {
-		imIO.SetDeltaTime(float32(currentTime-time) / float32(frequency))
-	} else {
-		imIO.SetDeltaTime(1.0 / 60.0)
-	}
-	time = currentTime
-
-	imgui.NewFrame()
-
-	if imgui.SliderFloat3("Ambient Color", &ambientColor.Data, 0, 1) {
-		simpleShader.SetUnifVec3("ambientLightColor", &ambientColor)
-	}
-
-	if imgui.SliderFloat("Ambient Color Strength", &ambientColorStrength, 0, 1) {
-		simpleShader.SetUnifFloat32("ambientStrength", ambientColorStrength)
-	}
-
-	if imgui.SliderFloat3("Light Pos 1", &lightPos1.Data, -10, 10) {
-		simpleShader.SetUnifVec3("lightPos1", &lightPos1)
-	}
-
-	if imgui.SliderFloat3("Light Color 1", &lightColor1.Data, 0, 1) {
-		simpleShader.SetUnifVec3("lightColor1", &lightColor1)
-	}
-
-	imgui.Render()
-}
-
-func draw() {
-
-	gl.Disable(gl.SCISSOR_TEST)
-	gl.Enable(gl.CULL_FACE)
-	gl.Enable(gl.DEPTH_TEST)
-	gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT)
-
-	simpleShader.Activate()
-
-	//DRAW
-	bo.Activate()
-	tempModelMat := modelMat.Clone()
-
-	for y := 0; y < 100; y++ {
-		for x := 0; x < 100; x++ {
-			simpleShader.SetUnifMat4("modelMat", &tempModelMat.Translate(gglm.NewVec3(-1, 0, 0)).Mat4)
-			gl.DrawElements(gl.TRIANGLES, int32(bo.IndexBuf.DataLen), gl.UNSIGNED_INT, gl.PtrOffset(0))
-		}
-		simpleShader.SetUnifMat4("modelMat", &tempModelMat.Translate(gglm.NewVec3(100, -1, 0)).Mat4)
-	}
-
-	simpleShader.SetUnifMat4("modelMat", &modelMat.Mat4)
-	bo.Deactivate()
-
-	drawUI()
-
-	window.GLSwap()
-}
-
-func drawUI() {
-
-	// Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
-	fbWidth, fbHeight := window.GLGetDrawableSize()
-	if fbWidth <= 0 || fbHeight <= 0 {
-		return
-	}
-
-	drawData := imgui.RenderedDrawData()
-	drawData.ScaleClipRects(imgui.Vec2{
-		X: float32(fbWidth) / float32(winWidth),
-		Y: float32(fbHeight) / float32(winHeight),
-	})
-
-	// Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, polygon fill
-	gl.Enable(gl.BLEND)
-	gl.BlendEquation(gl.FUNC_ADD)
-	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
-	gl.Disable(gl.CULL_FACE)
-	gl.Disable(gl.DEPTH_TEST)
-	gl.Enable(gl.SCISSOR_TEST)
-	gl.PolygonMode(gl.FRONT_AND_BACK, gl.FILL)
-
-	// Setup viewport, orthographic projection matrix
-	// Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right).
-	// DisplayMin is typically (0,0) for single viewport apps.
-
-	imShader.Activate()
-
-	gl.Uniform1i(gl.GetUniformLocation(imShader.ID, gl.Str("Texture\x00")), 0)
-
-	//PERF: only update the ortho matrix on window resize
-	orthoMat := gglm.Ortho(0, float32(winWidth), 0, float32(winHeight), 0, 20)
-	imShader.SetUnifMat4("ProjMtx", &orthoMat.Mat4)
-	gl.BindSampler(0, 0) // Rely on combined texture/sampler state.
-
-	// Recreate the VAO every time
-	// (This is to easily allow multiple GL contexts. VAO are not shared among GL contexts, and
-	// we don't track creation/deletion of windows so we don't have an obvious key to use to cache them.)
-	gl.BindVertexArray(imguiInfo.vaoID)
-	gl.BindBuffer(gl.ARRAY_BUFFER, imguiInfo.vboID)
-
-	vertexSize, vertexOffsetPos, vertexOffsetUv, vertexOffsetCol := imgui.VertexBufferLayout()
-	imShader.EnableAttribute("Position")
-	imShader.EnableAttribute("UV")
-	imShader.EnableAttribute("Color")
-	gl.VertexAttribPointerWithOffset(uint32(imShader.GetAttribLoc("Position")), 2, gl.FLOAT, false, int32(vertexSize), uintptr(vertexOffsetPos))
-	gl.VertexAttribPointerWithOffset(uint32(imShader.GetAttribLoc("UV")), 2, gl.FLOAT, false, int32(vertexSize), uintptr(vertexOffsetUv))
-	gl.VertexAttribPointerWithOffset(uint32(imShader.GetAttribLoc("Color")), 4, gl.UNSIGNED_BYTE, true, int32(vertexSize), uintptr(vertexOffsetCol))
-
-	indexSize := imgui.IndexBufferLayout()
-	drawType := gl.UNSIGNED_SHORT
-	if indexSize == 4 {
-		drawType = gl.UNSIGNED_INT
-	}
-
-	// Draw
-	for _, list := range drawData.CommandLists() {
-
-		vertexBuffer, vertexBufferSize := list.VertexBuffer()
-		gl.BindBuffer(gl.ARRAY_BUFFER, imguiInfo.vboID)
-		gl.BufferData(gl.ARRAY_BUFFER, vertexBufferSize, vertexBuffer, gl.STREAM_DRAW)
-
-		indexBuffer, indexBufferSize := list.IndexBuffer()
-		gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, imguiInfo.indexBufID)
-		gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, indexBufferSize, indexBuffer, gl.STREAM_DRAW)
-
-		for _, cmd := range list.Commands() {
-			if cmd.HasUserCallback() {
-				cmd.CallUserCallback(list)
-			} else {
-
-				gl.BindTexture(gl.TEXTURE_2D, imguiInfo.texID)
-				// gl.BindTexture(gl.TEXTURE_2D, uint32(cmd.TextureID()))
-				clipRect := cmd.ClipRect()
-				gl.Scissor(int32(clipRect.X), int32(fbHeight)-int32(clipRect.W), int32(clipRect.Z-clipRect.X), int32(clipRect.W-clipRect.Y))
-
-				gl.DrawElementsBaseVertex(gl.TRIANGLES, int32(cmd.ElementCount()), uint32(drawType), gl.PtrOffset(cmd.IndexOffset()*indexSize), int32(cmd.VertexOffset()))
-			}
-		}
-	}
-
-	gl.BindVertexArray(imguiInfo.vaoID)
-	gl.BindBuffer(gl.ARRAY_BUFFER, imguiInfo.vboID)
-	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, imguiInfo.indexBufID)
+	cam.Update()
+	simpleMat.SetUnifMat4("viewMat", &cam.ViewMat)
 }

materials/material.go

@@ -0,0 +1,125 @@
+package materials
+
+import (
+	"github.com/bloeys/gglm/gglm"
+	"github.com/bloeys/nmage/assert"
+	"github.com/bloeys/nmage/logging"
+	"github.com/bloeys/nmage/shaders"
+	"github.com/go-gl/gl/v4.1-core/gl"
+)
+
+type Material struct {
+	Name       string
+	ShaderProg shaders.ShaderProgram
+
+	DiffuseTex uint32
+
+	UnifLocs   map[string]int32
+	AttribLocs map[string]int32
+}
+
+func (m *Material) Bind() {
+
+	gl.UseProgram(m.ShaderProg.ID)
+
+	gl.ActiveTexture(gl.TEXTURE0)
+	gl.BindTexture(gl.TEXTURE_2D, m.DiffuseTex)
+}
+
+func (m *Material) UnBind() {
+	gl.UseProgram(0)
+
+	//TODO: Should we unbind textures here? Are these two lines needed?
+	// gl.ActiveTexture(gl.TEXTURE0)
+	// gl.BindTexture(gl.TEXTURE_2D, 0)
+}
+
+func (m *Material) GetAttribLoc(attribName string) int32 {
+
+	loc, ok := m.AttribLocs[attribName]
+	if ok {
+		return loc
+	}
+
+	loc = gl.GetAttribLocation(m.ShaderProg.ID, gl.Str(attribName+"\x00"))
+	assert.T(loc != -1, "Attribute '"+attribName+"' doesn't exist on material "+m.Name)
+	m.AttribLocs[attribName] = loc
+	return loc
+}
+
+func (m *Material) GetUnifLoc(uniformName string) int32 {
+
+	loc, ok := m.UnifLocs[uniformName]
+	if ok {
+		return loc
+	}
+
+	loc = gl.GetUniformLocation(m.ShaderProg.ID, gl.Str(uniformName+"\x00"))
+	assert.T(loc != -1, "Uniform '"+uniformName+"' doesn't exist on material "+m.Name)
+	m.UnifLocs[uniformName] = loc
+	return loc
+}
+
+func (m *Material) EnableAttribute(attribName string) {
+	gl.EnableVertexAttribArray(uint32(m.GetAttribLoc(attribName)))
+}
+
+func (m *Material) DisableAttribute(attribName string) {
+	gl.DisableVertexAttribArray(uint32(m.GetAttribLoc(attribName)))
+}
+
+func (m *Material) SetUnifInt32(uniformName string, val int32) {
+	gl.ProgramUniform1i(m.ShaderProg.ID, m.GetUnifLoc(uniformName), val)
+}
+
+func (m *Material) SetUnifFloat32(uniformName string, val float32) {
+	gl.ProgramUniform1f(m.ShaderProg.ID, m.GetUnifLoc(uniformName), val)
+}
+
+func (m *Material) SetUnifVec2(uniformName string, vec2 *gglm.Vec2) {
+	gl.ProgramUniform2fv(m.ShaderProg.ID, m.GetUnifLoc(uniformName), 1, &vec2.Data[0])
+}
+
+func (m *Material) SetUnifVec3(uniformName string, vec3 *gglm.Vec3) {
+	gl.ProgramUniform3fv(m.ShaderProg.ID, m.GetUnifLoc(uniformName), 1, &vec3.Data[0])
+}
+
+func (m *Material) SetUnifVec4(uniformName string, vec4 *gglm.Vec4) {
+	gl.ProgramUniform4fv(m.ShaderProg.ID, m.GetUnifLoc(uniformName), 1, &vec4.Data[0])
+}
+
+func (m *Material) SetUnifMat2(uniformName string, mat2 *gglm.Mat2) {
+	gl.ProgramUniformMatrix2fv(m.ShaderProg.ID, m.GetUnifLoc(uniformName), 1, false, &mat2.Data[0][0])
+}
+
+func (m *Material) SetUnifMat3(uniformName string, mat3 *gglm.Mat3) {
+	gl.ProgramUniformMatrix3fv(m.ShaderProg.ID, m.GetUnifLoc(uniformName), 1, false, &mat3.Data[0][0])
+}
+
+func (m *Material) SetUnifMat4(uniformName string, mat4 *gglm.Mat4) {
+	gl.ProgramUniformMatrix4fv(m.ShaderProg.ID, m.GetUnifLoc(uniformName), 1, false, &mat4.Data[0][0])
+}
+
+func (m *Material) Delete() {
+	gl.DeleteProgram(m.ShaderProg.ID)
+}
+
+func NewMaterial(matName, shaderPath string) *Material {
+
+	shdrProg, err := shaders.LoadAndCompileCombinedShader(shaderPath)
+	if err != nil {
+		logging.ErrLog.Fatalln("Failed to create new material. Err: ", err)
+	}
+
+	return &Material{Name: matName, ShaderProg: shdrProg, UnifLocs: make(map[string]int32), AttribLocs: make(map[string]int32)}
+}
+
+func NewMaterialSrc(matName string, shaderSrc []byte) *Material {
+
+	shdrProg, err := shaders.LoadAndCompileCombinedShaderSrc(shaderSrc)
+	if err != nil {
+		logging.ErrLog.Fatalln("Failed to create new material. Err: ", err)
+	}
+
+	return &Material{Name: matName, ShaderProg: shdrProg, UnifLocs: make(map[string]int32), AttribLocs: make(map[string]int32)}
+}

meshes/mesh.go

@@ -0,0 +1,165 @@
+package meshes
+
+import (
+	"errors"
+	"fmt"
+
+	"github.com/bloeys/assimp-go/asig"
+	"github.com/bloeys/gglm/gglm"
+	"github.com/bloeys/nmage/assert"
+	"github.com/bloeys/nmage/buffers"
+)
+
+type Mesh struct {
+	Name string
+	Buf  buffers.Buffer
+}
+
+func NewMesh(name, modelPath string, postProcessFlags asig.PostProcess) (*Mesh, error) {
+
+	scene, release, err := asig.ImportFile(modelPath, asig.PostProcessTriangulate|postProcessFlags)
+	if err != nil {
+		return nil, errors.New("Failed to load model. Err: " + err.Error())
+	}
+	defer release()
+
+	if len(scene.Meshes) == 0 {
+		return nil, errors.New("No meshes found in file: " + modelPath)
+	}
+
+	mesh := &Mesh{Name: name}
+	sceneMesh := scene.Meshes[0]
+	mesh.Buf = buffers.NewBuffer()
+
+	assert.T(len(sceneMesh.TexCoords[0]) > 0, "Mesh has no UV0")
+	layoutToUse := []buffers.Element{{ElementType: buffers.DataTypeVec3}, {ElementType: buffers.DataTypeVec3}, {ElementType: buffers.DataTypeVec2}}
+
+	if len(sceneMesh.ColorSets) > 0 && len(sceneMesh.ColorSets[0]) > 0 {
+		layoutToUse = append(layoutToUse, buffers.Element{ElementType: buffers.DataTypeVec4})
+	}
+	mesh.Buf.SetLayout(layoutToUse...)
+
+	var values []float32
+	arrs := []arrToInterleave{{V3s: sceneMesh.Vertices}, {V3s: sceneMesh.Normals}, {V2s: v3sToV2s(sceneMesh.TexCoords[0])}}
+
+	if len(sceneMesh.ColorSets) > 0 && len(sceneMesh.ColorSets[0]) > 0 {
+		arrs = append(arrs, arrToInterleave{V4s: sceneMesh.ColorSets[0]})
+	}
+
+	values = interleave(arrs...)
+
+	mesh.Buf.SetData(values)
+	mesh.Buf.SetIndexBufData(flattenFaces(sceneMesh.Faces))
+	return mesh, nil
+}
+
+func v3sToV2s(v3s []gglm.Vec3) []gglm.Vec2 {
+
+	v2s := make([]gglm.Vec2, len(v3s))
+	for i := 0; i < len(v3s); i++ {
+		v2s[i] = gglm.Vec2{
+			Data: [2]float32{v3s[i].X(), v3s[i].Y()},
+		}
+	}
+
+	return v2s
+}
+
+type arrToInterleave struct {
+	V2s []gglm.Vec2
+	V3s []gglm.Vec3
+	V4s []gglm.Vec4
+}
+
+func (a *arrToInterleave) get(i int) []float32 {
+
+	assert.T(len(a.V2s) == 0 || len(a.V3s) == 0, "One array should be set in arrToInterleave, but both arrays are set")
+	assert.T(len(a.V2s) == 0 || len(a.V4s) == 0, "One array should be set in arrToInterleave, but both arrays are set")
+	assert.T(len(a.V3s) == 0 || len(a.V4s) == 0, "One array should be set in arrToInterleave, but both arrays are set")
+
+	if len(a.V2s) > 0 {
+		return a.V2s[i].Data[:]
+	} else if len(a.V3s) > 0 {
+		return a.V3s[i].Data[:]
+	} else {
+		return a.V4s[i].Data[:]
+	}
+}
+
+func interleave(arrs ...arrToInterleave) []float32 {
+
+	assert.T(len(arrs) > 0, "No input sent to interleave")
+	assert.T(len(arrs[0].V2s) > 0 || len(arrs[0].V3s) > 0 || len(arrs[0].V4s) > 0, "Interleave arrays are empty")
+
+	elementCount := 0
+	if len(arrs[0].V2s) > 0 {
+		elementCount = len(arrs[0].V2s)
+	} else if len(arrs[0].V3s) > 0 {
+		elementCount = len(arrs[0].V3s)
+	} else {
+		elementCount = len(arrs[0].V4s)
+	}
+
+	//Calculate final size of the float buffer
+	totalSize := 0
+	for i := 0; i < len(arrs); i++ {
+
+		assert.T(len(arrs[i].V2s) == elementCount || len(arrs[i].V3s) == elementCount || len(arrs[i].V4s) == elementCount, "Mesh vertex data given to interleave is not the same length")
+
+		if len(arrs[i].V2s) > 0 {
+			totalSize += len(arrs[i].V2s) * 2
+		} else if len(arrs[i].V3s) > 0 {
+			totalSize += len(arrs[i].V3s) * 3
+		} else {
+			totalSize += len(arrs[i].V4s) * 4
+		}
+	}
+
+	out := make([]float32, 0, totalSize)
+	for i := 0; i < elementCount; i++ {
+		for arrToUse := 0; arrToUse < len(arrs); arrToUse++ {
+			out = append(out, arrs[arrToUse].get(i)...)
+		}
+	}
+
+	return out
+}
+
+func flattenVec3(vec3s []gglm.Vec3) []float32 {
+
+	floats := make([]float32, len(vec3s)*3)
+	for i := 0; i < len(vec3s); i++ {
+		floats[i*3+0] = vec3s[i].X()
+		floats[i*3+1] = vec3s[i].Y()
+		floats[i*3+2] = vec3s[i].Z()
+	}
+
+	return floats
+}
+
+func flattenVec4(vec4s []gglm.Vec4) []float32 {
+
+	floats := make([]float32, len(vec4s)*4)
+	for i := 0; i < len(vec4s); i++ {
+		floats[i*4+0] = vec4s[i].X()
+		floats[i*4+1] = vec4s[i].Y()
+		floats[i*4+2] = vec4s[i].Z()
+		floats[i*4+3] = vec4s[i].W()
+	}
+
+	return floats
+}
+
+func flattenFaces(faces []asig.Face) []uint32 {
+
+	assert.T(len(faces[0].Indices) == 3, fmt.Sprintf("Face doesn't have 3 indices. Index count: %v\n", len(faces[0].Indices)))
+
+	uints := make([]uint32, len(faces)*3)
+	for i := 0; i < len(faces); i++ {
+		uints[i*3+0] = uint32(faces[i].Indices[0])
+		uints[i*3+1] = uint32(faces[i].Indices[1])
+		uints[i*3+2] = uint32(faces[i].Indices[2])
+	}
+
+	return uints
+}

renderer/rend3dgl/rend3dgl.go

@@ -0,0 +1,41 @@
+package rend3dgl
+
+import (
+	"github.com/bloeys/gglm/gglm"
+	"github.com/bloeys/nmage/materials"
+	"github.com/bloeys/nmage/meshes"
+	"github.com/bloeys/nmage/renderer"
+	"github.com/go-gl/gl/v4.1-core/gl"
+)
+
+var _ renderer.Render = &Rend3DGL{}
+
+type Rend3DGL struct {
+	BoundMesh *meshes.Mesh
+	BoundMat  *materials.Material
+}
+
+func (r3d *Rend3DGL) Draw(mesh *meshes.Mesh, trMat *gglm.TrMat, mat *materials.Material) {
+
+	if mesh != r3d.BoundMesh {
+		mesh.Buf.Bind()
+		r3d.BoundMesh = mesh
+	}
+
+	if mat != r3d.BoundMat {
+		mat.Bind()
+		r3d.BoundMat = mat
+	}
+
+	mat.SetUnifMat4("modelMat", &trMat.Mat4)
+	gl.DrawElements(gl.TRIANGLES, mesh.Buf.IndexBufCount, gl.UNSIGNED_INT, gl.PtrOffset(0))
+}
+
+func (r3d *Rend3DGL) FrameEnd() {
+	r3d.BoundMesh = nil
+	r3d.BoundMat = nil
+}
+
+func NewRend3DGL() *Rend3DGL {
+	return &Rend3DGL{}
+}

renderer/renderer.go

@@ -0,0 +1,12 @@
+package renderer
+
+import (
+	"github.com/bloeys/gglm/gglm"
+	"github.com/bloeys/nmage/materials"
+	"github.com/bloeys/nmage/meshes"
+)
+
+type Render interface {
+	Draw(mesh *meshes.Mesh, trMat *gglm.TrMat, mat *materials.Material)
+	FrameEnd()
+}

res/shaders/imgui.frag.glsl

@@ -1,13 +0,0 @@
-#version 410
-
-uniform sampler2D Texture;
-
-in vec2 Frag_UV;
-in vec4 Frag_Color;
-
-out vec4 Out_Color;
-
-void main()
-{
-    Out_Color = vec4(Frag_Color.rgb, Frag_Color.a * texture(Texture, Frag_UV.st).r);
-}

res/shaders/imgui.vert.glsl

@@ -1,17 +0,0 @@
-#version 410
-
-uniform mat4 ProjMtx;
-
-in vec2 Position;
-in vec2 UV;
-in vec4 Color;
-
-out vec2 Frag_UV;
-out vec4 Frag_Color;
-
-void main()
-{
-    Frag_UV = UV;
-    Frag_Color = Color;
-    gl_Position = ProjMtx * vec4(Position.xy, 0, 1);
-}

res/shaders/simple.frag.glsl

@@ -1,23 +0,0 @@
-#version 410
-
-in vec3 vertColor;
-in vec3 vertNormal;
-in vec3 fragPos;
-
-out vec4 fragColor;
-
-uniform float ambientStrength = 0.1;
-uniform vec3 ambientLightColor = vec3(1, 1, 1);
-
-uniform vec3 lightPos1;
-uniform vec3 lightColor1;
-
-void main()
-{
-    // vec3 norm = normalize(Normal);
-    vec3 lightDir = normalize(lightPos1 - fragPos);  
-    float diffStrength = max(0.0, dot(normalize(vertNormal), lightDir));
-
-    vec3 finalAmbientColor = ambientLightColor * ambientStrength;
-    fragColor = vec4(vertColor * (finalAmbientColor + diffStrength*lightColor1), 1.0);
-} 

res/shaders/simple.glsl

@@ -0,0 +1,55 @@
+//shader:vertex
+#version 410
+
+layout(location=0) in vec3 vertPosIn;
+layout(location=1) in vec3 vertNormalIn;
+layout(location=2) in vec2 vertUV0In;
+layout(location=3) in vec3 vertColorIn;
+
+out vec3 vertNormal;
+out vec2 vertUV0;
+out vec3 vertColor;
+out vec3 fragPos;
+
+//MVP = Model View Projection
+uniform mat4 modelMat;
+uniform mat4 viewMat;
+uniform mat4 projMat;
+
+void main()
+{
+    vertNormal = mat3(transpose(inverse(modelMat))) * vertNormalIn;
+    vertUV0 = vertUV0In;
+    vertColor = vertColorIn;
+    fragPos = vec3(modelMat * vec4(vertPosIn, 1.0));
+
+    gl_Position = projMat * viewMat * modelMat * vec4(vertPosIn, 1.0);
+}
+
+//shader:fragment
+#version 410
+
+uniform float ambientStrength = 0.1;
+uniform vec3 ambientLightColor = vec3(1, 1, 1);
+
+uniform vec3 lightPos1;
+uniform vec3 lightColor1;
+
+uniform sampler2D diffTex;
+
+in vec3 vertColor;
+in vec3 vertNormal;
+in vec2 vertUV0;
+in vec3 fragPos;
+
+out vec4 fragColor;
+
+void main()
+{
+    vec3 lightDir = normalize(lightPos1 - fragPos);  
+    float diffStrength = max(0.0, dot(normalize(vertNormal), lightDir));
+
+    vec3 finalAmbientColor = ambientLightColor * ambientStrength;
+    vec4 texColor = texture(diffTex, vertUV0);
+    fragColor = vec4(texColor.rgb * vertColor * (finalAmbientColor + diffStrength*lightColor1) , texColor.a);
+} 

res/shaders/simple.vert.glsl

@@ -1,23 +0,0 @@
-#version 410
-
-in vec3 vertPosIn;
-in vec3 vertColorIn;
-in vec3 vertNormalIn;
-
-out vec3 vertColor;
-out vec3 vertNormal;
-out vec3 fragPos;
-
-//MVP = Model View Projection
-uniform mat4 modelMat;
-uniform mat4 viewMat;
-uniform mat4 projMat;
-
-void main()
-{
-    vertColor = vertColorIn;
-    vertNormal = mat3(transpose(inverse(modelMat))) * vertNormalIn;
-    fragPos = vec3(modelMat * vec4(vertPosIn, 1.0));
-
-    gl_Position = projMat * viewMat * modelMat * vec4(vertPosIn, 1.0);
-}

shaders/shader_program.go

@@ -1,8 +1,6 @@
 package shaders
 
 import (
-	"github.com/bloeys/gglm/gglm"
-	"github.com/bloeys/nmage/buffers"
 	"github.com/bloeys/nmage/logging"
 	"github.com/go-gl/gl/v4.1-core/gl"
 )
@@ -37,74 +35,3 @@ func (sp *ShaderProgram) Link() {
 		gl.DeleteShader(sp.FragShaderID)
 	}
 }
-
-func (sp *ShaderProgram) Activate() {
-	gl.UseProgram(sp.ID)
-}
-
-func (sp *ShaderProgram) Deactivate() {
-	gl.UseProgram(0)
-}
-
-func (sp *ShaderProgram) GetAttribLoc(attribName string) int32 {
-	return gl.GetAttribLocation(sp.ID, gl.Str(attribName+"\x00"))
-}
-
-func (sp *ShaderProgram) SetAttribute(attribName string, bufObj *buffers.BufferObject, buf *buffers.Buffer) {
-
-	bufObj.Activate()
-	buf.Activate()
-
-	attribLoc := sp.GetAttribLoc(attribName)
-	gl.VertexAttribPointer(uint32(attribLoc), buf.ElementCount, buf.ElementType, false, buf.GetSize(), gl.PtrOffset(0))
-
-	bufObj.Activate()
-	buf.Deactivate()
-}
-
-func (sp *ShaderProgram) EnableAttribute(attribName string) {
-	gl.EnableVertexAttribArray(uint32(sp.GetAttribLoc(attribName)))
-}
-
-func (sp *ShaderProgram) DisableAttribute(attribName string) {
-	gl.DisableVertexAttribArray(uint32(sp.GetAttribLoc(attribName)))
-}
-
-func (sp *ShaderProgram) SetUnifFloat32(uniformName string, val float32) {
-	loc := gl.GetUniformLocation(sp.ID, gl.Str(uniformName+"\x00"))
-	gl.ProgramUniform1f(sp.ID, loc, val)
-}
-
-func (sp *ShaderProgram) SetUnifVec2(uniformName string, vec2 *gglm.Vec2) {
-	loc := gl.GetUniformLocation(sp.ID, gl.Str(uniformName+"\x00"))
-	gl.ProgramUniform2fv(sp.ID, loc, 1, &vec2.Data[0])
-}
-
-func (sp *ShaderProgram) SetUnifVec3(uniformName string, vec3 *gglm.Vec3) {
-	loc := gl.GetUniformLocation(sp.ID, gl.Str(uniformName+"\x00"))
-	gl.ProgramUniform3fv(sp.ID, loc, 1, &vec3.Data[0])
-}
-
-func (sp *ShaderProgram) SetUnifVec4(uniformName string, vec4 *gglm.Vec4) {
-	loc := gl.GetUniformLocation(sp.ID, gl.Str(uniformName+"\x00"))
-	gl.ProgramUniform4fv(sp.ID, loc, 1, &vec4.Data[0])
-}
-
-func (sp *ShaderProgram) SetUnifMat2(uniformName string, mat2 *gglm.Mat2) {
-	loc := gl.GetUniformLocation(sp.ID, gl.Str(uniformName+"\x00"))
-	gl.ProgramUniformMatrix2fv(sp.ID, loc, 1, false, &mat2.Data[0][0])
-}
-
-func (sp *ShaderProgram) SetUnifMat3(uniformName string, mat3 *gglm.Mat3) {
-	loc := gl.GetUniformLocation(sp.ID, gl.Str(uniformName+"\x00"))
-	gl.ProgramUniformMatrix3fv(sp.ID, loc, 1, false, &mat3.Data[0][0])
-}
-
-func (sp *ShaderProgram) SetUnifMat4(uniformName string, mat4 *gglm.Mat4) {
-	loc := gl.GetUniformLocation(sp.ID, gl.Str(uniformName+"\x00"))
-	gl.ProgramUniformMatrix4fv(sp.ID, loc, 1, false, &mat4.Data[0][0])
-}
-
-func (sp *ShaderProgram) Delete() {
-	gl.DeleteProgram(sp.ID)
-}

shaders/shaders.go

@@ -1,6 +1,7 @@
 package shaders
 
 import (
+	"bytes"
 	"errors"
 	"os"
 	"strings"
@@ -28,14 +29,69 @@ func NewShaderProgram() (ShaderProgram, error) {
 	return ShaderProgram{ID: id}, nil
 }
 
-func LoadAndCompilerShader(shaderPath string, shaderType ShaderType) (Shader, error) {
+func LoadAndCompileCombinedShader(shaderPath string) (ShaderProgram, error) {
 
-	shaderSource, err := os.ReadFile(shaderPath)
+	combinedSource, err := os.ReadFile(shaderPath)
 	if err != nil {
 		logging.ErrLog.Println("Failed to read shader. Err: ", err)
-		return Shader{}, err
+		return ShaderProgram{}, err
 	}
 
+	return LoadAndCompileCombinedShaderSrc(combinedSource)
+
+}
+func LoadAndCompileCombinedShaderSrc(shaderSrc []byte) (ShaderProgram, error) {
+
+	shaderSources := bytes.Split(shaderSrc, []byte("//shader:"))
+	if len(shaderSources) == 1 {
+		return ShaderProgram{}, errors.New("failed to read combined shader. Did not find '//shader:vertex' or '//shader:fragment'")
+	}
+
+	shdrProg, err := NewShaderProgram()
+	if err != nil {
+		return ShaderProgram{}, errors.New("failed to create new shader program. Err: " + err.Error())
+	}
+
+	loadedShdrCount := 0
+	for i := 0; i < len(shaderSources); i++ {
+
+		src := shaderSources[i]
+
+		//This can happen when the shader type is at the start of the file
+		if len(bytes.TrimSpace(src)) == 0 {
+			continue
+		}
+
+		var shdrType ShaderType
+		if bytes.HasPrefix(src, []byte("vertex")) {
+			src = src[6:]
+			shdrType = VertexShaderType
+		} else if bytes.HasPrefix(src, []byte("fragment")) {
+			src = src[8:]
+			shdrType = FragmentShaderType
+		} else {
+			return ShaderProgram{}, errors.New("unknown shader type. Must be '//shader:vertex' or '//shader:fragment'")
+		}
+
+		shdr, err := CompileShaderOfType(src, shdrType)
+		if err != nil {
+			return ShaderProgram{}, err
+		}
+
+		loadedShdrCount++
+		shdrProg.AttachShader(shdr)
+	}
+
+	if loadedShdrCount == 0 {
+		return ShaderProgram{}, errors.New("no valid shaders found. Please put '//shader:vertex' or '//shader:fragment' before your shaders")
+	}
+
+	shdrProg.Link()
+	return shdrProg, nil
+}
+
+func CompileShaderOfType(shaderSource []byte, shaderType ShaderType) (Shader, error) {
+
 	shaderID := gl.CreateShader(uint32(shaderType))
 	if shaderID == 0 {
 		logging.ErrLog.Println("Failed to create shader.")

timing/timing.go

@@ -1,11 +1,19 @@
 package timing
 
-import "time"
+import (
+	"time"
+)
 
 var (
 	dt         float32 = 0.01
 	frameStart time.Time
 	startTime  time.Time
+
+	//fps calculator vars
+	dtAccum                  float32 = 1
+	lastElapsedTime          uint64  = 0
+	framesSinceLastFPSUpdate uint    = 0
+	avgFps                   float32 = 1
 )
 
 func Init() {
@@ -13,18 +21,42 @@ func Init() {
 }
 
 func FrameStarted() {
+
 	frameStart = time.Now()
+
+	//fps stuff
+	dtAccum += dt
+	framesSinceLastFPSUpdate++
+	et := ElapsedTime()
+	if et > lastElapsedTime {
+		avgDT := dtAccum / float32(framesSinceLastFPSUpdate)
+		avgFps = 1 / avgDT
+
+		dtAccum = 0
+		framesSinceLastFPSUpdate = 0
+	}
+	lastElapsedTime = et
 }
 
 func FrameEnded() {
+
+	//Calculate new dt
 	dt = float32(time.Since(frameStart).Seconds())
+	if dt == 0 {
+		dt = float32(time.Microsecond.Seconds())
+	}
 }
 
-//DT is frame deltatime in milliseconds
+//DT is frame deltatime in seconds
 func DT() float32 {
 	return dt
 }
 
+//GetAvgFPS returns the fps averaged over 1 second
+func GetAvgFPS() float32 {
+	return avgFps
+}
+
 //ElapsedTime is time since game start
 func ElapsedTime() uint64 {
 	return uint64(time.Since(startTime).Seconds())

ui/imgui/imgui.go

@@ -0,0 +1,252 @@
+package nmageimgui
+
+import (
+	"github.com/bloeys/gglm/gglm"
+	"github.com/bloeys/nmage/assert"
+	"github.com/bloeys/nmage/materials"
+	"github.com/bloeys/nmage/timing"
+	"github.com/go-gl/gl/v4.1-core/gl"
+	"github.com/inkyblackness/imgui-go/v4"
+	"github.com/veandco/go-sdl2/sdl"
+)
+
+type ImguiInfo struct {
+	ImCtx *imgui.Context
+
+	Mat        *materials.Material
+	VaoID      uint32
+	VboID      uint32
+	IndexBufID uint32
+	TexID      uint32
+}
+
+func (i *ImguiInfo) FrameStart(winWidth, winHeight float32) {
+
+	if err := i.ImCtx.SetCurrent(); err != nil {
+		assert.T(false, "Setting imgui ctx as current failed. Err: "+err.Error())
+	}
+
+	imIO := imgui.CurrentIO()
+	imIO.SetDisplaySize(imgui.Vec2{X: float32(winWidth), Y: float32(winHeight)})
+	imIO.SetDeltaTime(timing.DT())
+
+	imgui.NewFrame()
+}
+
+func (i *ImguiInfo) Render(winWidth, winHeight float32, fbWidth, fbHeight int32) {
+
+	if err := i.ImCtx.SetCurrent(); err != nil {
+		assert.T(false, "Setting imgui ctx as current failed. Err: "+err.Error())
+	}
+
+	imgui.Render()
+
+	// Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
+	if fbWidth <= 0 || fbHeight <= 0 {
+		return
+	}
+
+	drawData := imgui.RenderedDrawData()
+	drawData.ScaleClipRects(imgui.Vec2{
+		X: float32(fbWidth) / float32(winWidth),
+		Y: float32(fbHeight) / float32(winHeight),
+	})
+
+	// Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, polygon fill
+	gl.Enable(gl.BLEND)
+	gl.BlendEquation(gl.FUNC_ADD)
+	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
+	gl.Disable(gl.CULL_FACE)
+	gl.Disable(gl.DEPTH_TEST)
+	gl.Enable(gl.SCISSOR_TEST)
+	gl.PolygonMode(gl.FRONT_AND_BACK, gl.FILL)
+
+	// Setup viewport, orthographic projection matrix
+	// Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right).
+	// DisplayMin is typically (0,0) for single viewport apps.
+
+	i.Mat.Bind()
+	i.Mat.SetUnifInt32("Texture", 0)
+
+	//PERF: only update the ortho matrix on window resize
+	orthoMat := gglm.Ortho(0, float32(winWidth), 0, float32(winHeight), 0, 20)
+	i.Mat.SetUnifMat4("ProjMtx", &orthoMat.Mat4)
+	gl.BindSampler(0, 0) // Rely on combined texture/sampler state.
+
+	// Recreate the VAO every time
+	// (This is to easily allow multiple GL contexts. VAO are not shared among GL contexts, and
+	// we don't track creation/deletion of windows so we don't have an obvious key to use to cache them.)
+	gl.BindVertexArray(i.VaoID)
+	gl.BindBuffer(gl.ARRAY_BUFFER, i.VboID)
+
+	vertexSize, vertexOffsetPos, vertexOffsetUv, vertexOffsetCol := imgui.VertexBufferLayout()
+	i.Mat.EnableAttribute("Position")
+	i.Mat.EnableAttribute("UV")
+	i.Mat.EnableAttribute("Color")
+	gl.VertexAttribPointerWithOffset(uint32(i.Mat.GetAttribLoc("Position")), 2, gl.FLOAT, false, int32(vertexSize), uintptr(vertexOffsetPos))
+	gl.VertexAttribPointerWithOffset(uint32(i.Mat.GetAttribLoc("UV")), 2, gl.FLOAT, false, int32(vertexSize), uintptr(vertexOffsetUv))
+	gl.VertexAttribPointerWithOffset(uint32(i.Mat.GetAttribLoc("Color")), 4, gl.UNSIGNED_BYTE, true, int32(vertexSize), uintptr(vertexOffsetCol))
+
+	indexSize := imgui.IndexBufferLayout()
+	drawType := gl.UNSIGNED_SHORT
+	if indexSize == 4 {
+		drawType = gl.UNSIGNED_INT
+	}
+
+	// Draw
+	for _, list := range drawData.CommandLists() {
+
+		vertexBuffer, vertexBufferSize := list.VertexBuffer()
+		gl.BindBuffer(gl.ARRAY_BUFFER, i.VboID)
+		gl.BufferData(gl.ARRAY_BUFFER, vertexBufferSize, vertexBuffer, gl.STREAM_DRAW)
+
+		indexBuffer, indexBufferSize := list.IndexBuffer()
+		gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, i.IndexBufID)
+		gl.BufferData(gl.ELEMENT_ARRAY_BUFFER, indexBufferSize, indexBuffer, gl.STREAM_DRAW)
+
+		for _, cmd := range list.Commands() {
+			if cmd.HasUserCallback() {
+				cmd.CallUserCallback(list)
+			} else {
+
+				gl.BindTexture(gl.TEXTURE_2D, i.TexID)
+				clipRect := cmd.ClipRect()
+				gl.Scissor(int32(clipRect.X), int32(fbHeight)-int32(clipRect.W), int32(clipRect.Z-clipRect.X), int32(clipRect.W-clipRect.Y))
+
+				gl.DrawElementsBaseVertex(gl.TRIANGLES, int32(cmd.ElementCount()), uint32(drawType), gl.PtrOffset(cmd.IndexOffset()*indexSize), int32(cmd.VertexOffset()))
+			}
+		}
+	}
+
+	//Reset gl state
+	gl.Disable(gl.SCISSOR_TEST)
+	gl.Enable(gl.CULL_FACE)
+	gl.Enable(gl.DEPTH_TEST)
+}
+
+func (i *ImguiInfo) AddFontTTF(fontPath string, fontSize float32, fontConfig *imgui.FontConfig, glyphRanges *imgui.GlyphRanges) imgui.Font {
+
+	fontConfigToUse := imgui.DefaultFontConfig
+	if fontConfig != nil {
+		fontConfigToUse = *fontConfig
+	}
+
+	glyphRangesToUse := imgui.EmptyGlyphRanges
+	if glyphRanges != nil {
+		glyphRangesToUse = *glyphRanges
+	}
+
+	imIO := imgui.CurrentIO()
+
+	a := imIO.Fonts()
+	f := a.AddFontFromFileTTFV(fontPath, fontSize, fontConfigToUse, glyphRangesToUse)
+	image := a.TextureDataAlpha8()
+
+	gl.BindTexture(gl.TEXTURE_2D, i.TexID)
+	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RED, int32(image.Width), int32(image.Height), 0, gl.RED, gl.UNSIGNED_BYTE, image.Pixels)
+
+	return f
+}
+
+const imguiShdrSrc = `
+//shader:vertex
+#version 410
+
+uniform mat4 ProjMtx;
+
+in vec2 Position;
+in vec2 UV;
+in vec4 Color;
+
+out vec2 Frag_UV;
+out vec4 Frag_Color;
+
+void main()
+{
+    Frag_UV = UV;
+    Frag_Color = Color;
+    gl_Position = ProjMtx * vec4(Position.xy, 0, 1);
+}
+
+//shader:fragment
+#version 410
+
+uniform sampler2D Texture;
+
+in vec2 Frag_UV;
+in vec4 Frag_Color;
+
+out vec4 Out_Color;
+
+void main()
+{
+    Out_Color = vec4(Frag_Color.rgb, Frag_Color.a * texture(Texture, Frag_UV.st).r);
+}
+`
+
+func NewImGUI() ImguiInfo {
+
+	imguiInfo := ImguiInfo{
+		ImCtx: imgui.CreateContext(nil),
+		Mat:   materials.NewMaterialSrc("ImGUI Mat", []byte(imguiShdrSrc)),
+	}
+
+	imIO := imgui.CurrentIO()
+	imIO.SetBackendFlags(imIO.GetBackendFlags() | imgui.BackendFlagsRendererHasVtxOffset)
+
+	gl.GenVertexArrays(1, &imguiInfo.VaoID)
+	gl.GenBuffers(1, &imguiInfo.VboID)
+	gl.GenBuffers(1, &imguiInfo.IndexBufID)
+	gl.GenTextures(1, &imguiInfo.TexID)
+
+	// Upload font to gpu
+	gl.BindTexture(gl.TEXTURE_2D, imguiInfo.TexID)
+	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
+	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
+	gl.PixelStorei(gl.UNPACK_ROW_LENGTH, 0)
+
+	image := imIO.Fonts().TextureDataAlpha8()
+	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RED, int32(image.Width), int32(image.Height), 0, gl.RED, gl.UNSIGNED_BYTE, image.Pixels)
+
+	// Store our identifier
+	imIO.Fonts().SetTextureID(imgui.TextureID(imguiInfo.TexID))
+
+	//Shader attributes
+	imguiInfo.Mat.Bind()
+	imguiInfo.Mat.EnableAttribute("Position")
+	imguiInfo.Mat.EnableAttribute("UV")
+	imguiInfo.Mat.EnableAttribute("Color")
+	imguiInfo.Mat.UnBind()
+
+	//Init imgui input mapping
+	keys := map[int]int{
+		imgui.KeyTab:        sdl.SCANCODE_TAB,
+		imgui.KeyLeftArrow:  sdl.SCANCODE_LEFT,
+		imgui.KeyRightArrow: sdl.SCANCODE_RIGHT,
+		imgui.KeyUpArrow:    sdl.SCANCODE_UP,
+		imgui.KeyDownArrow:  sdl.SCANCODE_DOWN,
+		imgui.KeyPageUp:     sdl.SCANCODE_PAGEUP,
+		imgui.KeyPageDown:   sdl.SCANCODE_PAGEDOWN,
+		imgui.KeyHome:       sdl.SCANCODE_HOME,
+		imgui.KeyEnd:        sdl.SCANCODE_END,
+		imgui.KeyInsert:     sdl.SCANCODE_INSERT,
+		imgui.KeyDelete:     sdl.SCANCODE_DELETE,
+		imgui.KeyBackspace:  sdl.SCANCODE_BACKSPACE,
+		imgui.KeySpace:      sdl.SCANCODE_BACKSPACE,
+		imgui.KeyEnter:      sdl.SCANCODE_RETURN,
+		imgui.KeyEscape:     sdl.SCANCODE_ESCAPE,
+		imgui.KeyA:          sdl.SCANCODE_A,
+		imgui.KeyC:          sdl.SCANCODE_C,
+		imgui.KeyV:          sdl.SCANCODE_V,
+		imgui.KeyX:          sdl.SCANCODE_X,
+		imgui.KeyY:          sdl.SCANCODE_Y,
+		imgui.KeyZ:          sdl.SCANCODE_Z,
+	}
+
+	// Keyboard mapping. ImGui will use those indices to peek into the io.KeysDown[] array.
+	for imguiKey, nativeKey := range keys {
+		imIO.KeyMap(imguiKey, nativeKey)
+	}
+
+	return imguiInfo
+}