TextureLoadOptions+fix DT bug+remove SetAttribute

assets/assets.go

@@ -5,7 +5,7 @@ var (
 	TexturePaths map[string]uint32  = make(map[string]uint32)
 )
 
-func SetTexture(t Texture) {
+func AddTextureToCache(t Texture) {
 
 	if _, ok := TexturePaths[t.Path]; ok {
 		return
@@ -16,12 +16,12 @@ func SetTexture(t Texture) {
 	TexturePaths[t.Path] = t.TexID
 }
 
-func GetTexture(texID uint32) (Texture, bool) {
+func GetTextureFromCacheID(texID uint32) (Texture, bool) {
 	tex, ok := Textures[texID]
 	return tex, ok
 }
 
-func GetTexturePath(path string) (Texture, bool) {
+func GetTextureFromCachePath(path string) (Texture, bool) {
 	tex, ok := Textures[TexturePaths[path]]
 	return tex, ok
 }

assets/textures.go

@@ -24,11 +24,23 @@ type Texture struct {
 	Pixels []byte
 }
 
-func LoadPNGTexture(file string) (Texture, error) {
+type TextureLoadOptions struct {
+	TryLoadFromCache bool
+	WriteToCache     bool
+	GenMipMaps       bool
+}
 
-	if tex, ok := GetTexturePath(file); ok {
+func LoadPNGTexture(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)
@@ -72,14 +84,19 @@ func LoadPNGTexture(file string) (Texture, error) {
 	// 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_MIPMAP_LINEAR)
+	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]))
-	gl.GenerateMipmap(gl.TEXTURE_2D)
 
-	SetTexture(tex)
+	if loadOptions.GenMipMaps {
+		gl.GenerateMipmap(tex.TexID)
+	}
+
+	if loadOptions.WriteToCache {
+		AddTextureToCache(tex)
+	}
 
 	return tex, nil
 }

buffers/buffers.go

@@ -54,6 +54,8 @@ func (b *Buffer) GetLayout() []Element {
 	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
@@ -64,6 +66,20 @@ func (b *Buffer) SetLayout(layout ...Element) {
 		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 {

main.go

@@ -18,15 +18,6 @@ import (
 	"github.com/veandco/go-sdl2/sdl"
 )
 
-//BUGS:
-// need to rebind the texutre if the texture (or any material values) change between draw calls
-// DT handling for when it is zero is wrong! (Gives 1000 DT)
-
-//nMage TODO:
-//	* Allow texture loading without cache
-//	* Move SetAttribute away from material struct
-//	* Create VAO struct independent from VBO to support multi-VBO use cases (e.g. instancing)
-
 //TODO: Tasks:
 // Build simple game
 // Integrate physx
@@ -34,6 +25,7 @@ import (
 // Camera class
 
 //Low Priority:
+// 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?
@@ -76,14 +68,13 @@ func (g *OurGame) Init() {
 	}
 
 	//Load textures
-	tex, err := assets.LoadPNGTexture("./res/textures/Low poly planet.png")
+	tex, err := assets.LoadPNGTexture("./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
-	simpleMat.SetAttribute(cubeMesh.Buf)
 
 	//Movement, scale and rotation
 	translationMat := gglm.NewTranslationMat(gglm.NewVec3(0, 0, 0))

materials/material.go

@@ -3,7 +3,6 @@ package materials
 import (
 	"github.com/bloeys/gglm/gglm"
 	"github.com/bloeys/nmage/asserts"
-	"github.com/bloeys/nmage/buffers"
 	"github.com/bloeys/nmage/logging"
 	"github.com/bloeys/nmage/shaders"
 	"github.com/go-gl/gl/v4.1-core/gl"
@@ -61,23 +60,6 @@ func (m *Material) GetUnifLoc(uniformName string) int32 {
 	return loc
 }
 
-func (m *Material) SetAttribute(bufObj buffers.Buffer) {
-
-	bufObj.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, bufObj.BufID)
-
-	layout := bufObj.GetLayout()
-	for i := 0; i < len(layout); i++ {
-		gl.EnableVertexAttribArray(uint32(i))
-		gl.VertexAttribPointer(uint32(i), layout[i].ElementType.CompCount(), layout[i].ElementType.GLType(), false, bufObj.Stride, gl.PtrOffset(layout[i].Offset))
-	}
-
-	bufObj.UnBind()
-	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
-}
-
 func (m *Material) EnableAttribute(attribName string) {
 	gl.EnableVertexAttribArray(uint32(m.GetAttribLoc(attribName)))
 }

timing/timing.go

@@ -43,7 +43,7 @@ func FrameEnded() {
 	//Calculate new dt
 	dt = float32(time.Since(frameStart).Seconds())
 	if dt == 0 {
-		dt = float32(time.Microsecond)
+		dt = float32(time.Microsecond.Seconds())
 	}
 }