Make const value naming upper snake case

.gitignore

@@ -15,4 +15,7 @@
 vendor/
 .vscode/
 imgui.ini
-*~
+*~
+
+# Custom
+*.pprof

assets/textures.go

@@ -23,6 +23,15 @@ const (
 	ColorFormat_RGBA8
 )
 
+var (
+	DefaultBlackTexId    Texture
+	DefaultWhiteTexId    Texture
+	DefaultDiffuseTexId  Texture
+	DefaultSpecularTexId Texture
+	DefaultNormalTexId   Texture
+	DefaultEmissionTexId Texture
+)
+
 type Texture struct {
 	// Path only exists for textures loaded from disk
 	Path string

buffers/framebuffer.go

@@ -42,6 +42,7 @@ const (
 	FramebufferAttachmentDataFormat_Unknown FramebufferAttachmentDataFormat = iota
 	FramebufferAttachmentDataFormat_R32Int
 	FramebufferAttachmentDataFormat_RGBA8
+	FramebufferAttachmentDataFormat_RGBAF16
 	FramebufferAttachmentDataFormat_SRGBA
 	FramebufferAttachmentDataFormat_DepthF32
 	FramebufferAttachmentDataFormat_Depth24Stencil8
@@ -50,7 +51,8 @@ const (
 func (f FramebufferAttachmentDataFormat) IsColorFormat() bool {
 	return f == FramebufferAttachmentDataFormat_R32Int ||
 		f == FramebufferAttachmentDataFormat_RGBA8 ||
-		f == FramebufferAttachmentDataFormat_SRGBA
+		f == FramebufferAttachmentDataFormat_SRGBA ||
+		f == FramebufferAttachmentDataFormat_RGBAF16
 }
 
 func (f FramebufferAttachmentDataFormat) IsDepthFormat() bool {
@@ -65,6 +67,8 @@ func (f FramebufferAttachmentDataFormat) GlInternalFormat() int32 {
 		return gl.R32I
 	case FramebufferAttachmentDataFormat_RGBA8:
 		return gl.RGB8
+	case FramebufferAttachmentDataFormat_RGBAF16:
+		return gl.RGBA16F
 	case FramebufferAttachmentDataFormat_SRGBA:
 		return gl.SRGB_ALPHA
 	case FramebufferAttachmentDataFormat_DepthF32:
@@ -85,6 +89,8 @@ func (f FramebufferAttachmentDataFormat) GlFormat() uint32 {
 
 	case FramebufferAttachmentDataFormat_RGBA8:
 		fallthrough
+	case FramebufferAttachmentDataFormat_RGBAF16:
+		fallthrough
 	case FramebufferAttachmentDataFormat_SRGBA:
 		return gl.RGBA
 
@@ -100,6 +106,33 @@ func (f FramebufferAttachmentDataFormat) GlFormat() uint32 {
 	}
 }
 
+func (f FramebufferAttachmentDataFormat) GlComponentType() uint32 {
+
+	switch f {
+
+	case FramebufferAttachmentDataFormat_R32Int:
+		return gl.INT
+
+	case FramebufferAttachmentDataFormat_RGBA8:
+		fallthrough
+	case FramebufferAttachmentDataFormat_SRGBA:
+		return gl.UNSIGNED_BYTE
+
+	case FramebufferAttachmentDataFormat_RGBAF16:
+		// Seems this is fine to be float instead of half float
+		fallthrough
+	case FramebufferAttachmentDataFormat_DepthF32:
+		return gl.FLOAT
+
+	case FramebufferAttachmentDataFormat_Depth24Stencil8:
+		return gl.UNSIGNED_INT_24_8
+
+	default:
+		logging.ErrLog.Fatalf("unknown framebuffer attachment data format. Format=%d\n", f)
+		return 0
+	}
+}
+
 type FramebufferAttachment struct {
 	Id     uint32
 	Type   FramebufferAttachmentType
@@ -124,7 +157,7 @@ func (fbo *Framebuffer) BindWithViewport() {
 	gl.Viewport(0, 0, int32(fbo.Width), int32(fbo.Height))
 }
 
-// Clear calls gl.Clear with the fob's clear flags.
+// Clear calls gl.Clear with the fbo's clear flags.
 // Note that the fbo must be complete and bound.
 // Calling this without a bound fbo will clear something else, like your screen.
 func (fbo *Framebuffer) Clear() {
@@ -207,7 +240,17 @@ func (fbo *Framebuffer) NewColorAttachment(
 		}
 
 		gl.BindTexture(gl.TEXTURE_2D, a.Id)
-		gl.TexImage2D(gl.TEXTURE_2D, 0, attachFormat.GlInternalFormat(), int32(fbo.Width), int32(fbo.Height), 0, attachFormat.GlFormat(), gl.UNSIGNED_BYTE, nil)
+		gl.TexImage2D(
+			gl.TEXTURE_2D,
+			0,
+			attachFormat.GlInternalFormat(),
+			int32(fbo.Width),
+			int32(fbo.Height),
+			0,
+			attachFormat.GlFormat(),
+			attachFormat.GlComponentType(),
+			nil,
+		)
 
 		gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
 		gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
@@ -298,7 +341,17 @@ func (fbo *Framebuffer) NewDepthAttachment(
 		}
 
 		gl.BindTexture(gl.TEXTURE_2D, a.Id)
-		gl.TexImage2D(gl.TEXTURE_2D, 0, attachFormat.GlInternalFormat(), int32(fbo.Width), int32(fbo.Height), 0, attachFormat.GlFormat(), gl.FLOAT, nil)
+		gl.TexImage2D(
+			gl.TEXTURE_2D,
+			0,
+			attachFormat.GlInternalFormat(),
+			int32(fbo.Width),
+			int32(fbo.Height),
+			0,
+			attachFormat.GlFormat(),
+			attachFormat.GlComponentType(),
+			nil,
+		)
 
 		gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
 		gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST)
@@ -341,7 +394,17 @@ func (fbo *Framebuffer) NewDepthAttachment(
 
 		gl.BindTexture(gl.TEXTURE_CUBE_MAP, a.Id)
 		for i := 0; i < 6; i++ {
-			gl.TexImage2D(uint32(gl.TEXTURE_CUBE_MAP_POSITIVE_X+i), 0, attachFormat.GlInternalFormat(), int32(fbo.Width), int32(fbo.Height), 0, attachFormat.GlFormat(), gl.FLOAT, nil)
+			gl.TexImage2D(
+				uint32(gl.TEXTURE_CUBE_MAP_POSITIVE_X+i),
+				0,
+				attachFormat.GlInternalFormat(),
+				int32(fbo.Width),
+				int32(fbo.Height),
+				0,
+				attachFormat.GlFormat(),
+				attachFormat.GlComponentType(),
+				nil,
+			)
 		}
 
 		gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
@@ -398,7 +461,7 @@ func (fbo *Framebuffer) NewDepthCubemapArrayAttachment(
 		6*numCubemaps,
 		0,
 		attachFormat.GlFormat(),
-		gl.FLOAT,
+		attachFormat.GlComponentType(),
 		nil,
 	)
 
@@ -455,7 +518,7 @@ func (fbo *Framebuffer) NewDepthTextureArrayAttachment(
 		numTextures,
 		0,
 		attachFormat.GlFormat(),
-		gl.FLOAT,
+		attachFormat.GlComponentType(),
 		nil,
 	)
 
@@ -513,7 +576,17 @@ func (fbo *Framebuffer) NewDepthStencilAttachment(
 		}
 
 		gl.BindTexture(gl.TEXTURE_2D, a.Id)
-		gl.TexImage2D(gl.TEXTURE_2D, 0, attachFormat.GlInternalFormat(), int32(fbo.Width), int32(fbo.Height), 0, attachFormat.GlFormat(), gl.UNSIGNED_INT_24_8, nil)
+		gl.TexImage2D(
+			gl.TEXTURE_2D,
+			0,
+			attachFormat.GlInternalFormat(),
+			int32(fbo.Width),
+			int32(fbo.Height),
+			0,
+			attachFormat.GlFormat(),
+			attachFormat.GlComponentType(),
+			nil,
+		)
 
 		gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
 		gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST)

camera/camera.go

@@ -41,7 +41,7 @@ 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)
+		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
 	}
@@ -59,9 +59,9 @@ func (c *Camera) UpdateRotation(pitch, yaw float32) {
 	c.Update()
 }
 
-func NewPerspective(pos, forward, worldUp *gglm.Vec3, nearClip, farClip, fovRadians, aspectRatio float32) *Camera {
+func NewPerspective(pos, forward, worldUp *gglm.Vec3, nearClip, farClip, fovRadians, aspectRatio float32) Camera {
 
-	cam := &Camera{
+	cam := Camera{
 		Type:    Type_Perspective,
 		Pos:     *pos,
 		Forward: *forward,
@@ -78,9 +78,9 @@ func NewPerspective(pos, forward, worldUp *gglm.Vec3, nearClip, farClip, fovRadi
 	return cam
 }
 
-func NewOrthographic(pos, forward, worldUp *gglm.Vec3, nearClip, farClip, left, right, top, bottom float32) *Camera {
+func NewOrthographic(pos, forward, worldUp *gglm.Vec3, nearClip, farClip, left, right, top, bottom float32) Camera {
 
-	cam := &Camera{
+	cam := Camera{
 		Type:    Type_Orthographic,
 		Pos:     *pos,
 		Forward: *forward,

engine/engine.go

@@ -1,12 +1,14 @@
 package engine
 
 import (
+	"image"
+	"image/color"
 	"runtime"
 
 	imgui "github.com/AllenDang/cimgui-go"
 	"github.com/bloeys/nmage/assert"
+	"github.com/bloeys/nmage/assets"
 	"github.com/bloeys/nmage/input"
-	"github.com/bloeys/nmage/renderer"
 	"github.com/bloeys/nmage/timing"
 	nmageimgui "github.com/bloeys/nmage/ui/imgui"
 	"github.com/go-gl/gl/v4.1-core/gl"
@@ -28,7 +30,6 @@ type Window struct {
 	SDLWin         *sdl.Window
 	GlCtx          sdl.GLContext
 	EventCallbacks []func(sdl.Event)
-	Rend           renderer.Render
 }
 
 func (w *Window) handleInputs() {
@@ -167,42 +168,45 @@ func initSDL() error {
 	return nil
 }
 
-func CreateOpenGLWindow(title string, x, y, width, height int32, flags WindowFlags, rend renderer.Render) (*Window, error) {
+func CreateOpenGLWindow(title string, x, y, width, height int32, flags WindowFlags) (Window, error) {
-	return createWindow(title, x, y, width, height, WindowFlags_OPENGL|flags, rend)
+	return createWindow(title, x, y, width, height, WindowFlags_OPENGL|flags)
 }
 
-func CreateOpenGLWindowCentered(title string, width, height int32, flags WindowFlags, rend renderer.Render) (*Window, error) {
+func CreateOpenGLWindowCentered(title string, width, height int32, flags WindowFlags) (Window, error) {
-	return createWindow(title, sdl.WINDOWPOS_CENTERED, sdl.WINDOWPOS_CENTERED, width, height, WindowFlags_OPENGL|flags, rend)
+	return createWindow(title, sdl.WINDOWPOS_CENTERED, sdl.WINDOWPOS_CENTERED, width, height, WindowFlags_OPENGL|flags)
 }
 
-func createWindow(title string, x, y, width, height int32, flags WindowFlags, rend renderer.Render) (*Window, error) {
+func createWindow(title string, x, y, width, height int32, flags WindowFlags) (Window, error) {
 
 	assert.T(isInited, "engine.Init() was not called!")
 
-	sdlWin, err := sdl.CreateWindow(title, x, y, width, height, uint32(flags))
+	win := Window{
-	if err != nil {
+		SDLWin:         nil,
-		return nil, err
-	}
-
-	win := &Window{
-		SDLWin:         sdlWin,
 		EventCallbacks: make([]func(sdl.Event), 0),
-		Rend:           rend,
 	}
 
-	win.GlCtx, err = sdlWin.GLCreateContext()
+	var err error
+
+	win.SDLWin, err = sdl.CreateWindow(title, x, y, width, height, uint32(flags))
 	if err != nil {
-		return nil, err
+		return win, err
+	}
+
+	win.GlCtx, err = win.SDLWin.GLCreateContext()
+	if err != nil {
+		return win, err
 	}
 
 	err = initOpenGL()
 	if err != nil {
-		return nil, err
+		return win, err
 	}
 
+	setupDefaultTextures()
+
 	// Get rid of the blinding white startup screen (unfortunately there is still one frame of white)
 	gl.Clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT | gl.STENCIL_BUFFER_BIT)
-	sdlWin.GLSwap()
+	win.SDLWin.GLSwap()
 
 	return win, err
 }
@@ -229,6 +233,57 @@ func initOpenGL() error {
 	return nil
 }
 
+func setupDefaultTextures() error {
+
+	// 1x1 black texture
+	defaultBlackImg := image.NewNRGBA(image.Rect(0, 0, 1, 1))
+	defaultBlackImg.Set(0, 0, color.NRGBA{R: 0, G: 0, B: 0, A: 1})
+	defaultBlackImgTex, err := assets.LoadTextureInMemPngImg(defaultBlackImg, &assets.TextureLoadOptions{NoSrgba: true})
+	if err != nil {
+		return err
+	}
+	assets.DefaultBlackTexId = defaultBlackImgTex
+
+	// 1x1 white texture
+	defaultWhiteImg := image.NewNRGBA(image.Rect(0, 0, 1, 1))
+	defaultWhiteImg.Set(0, 0, color.NRGBA{R: 255, G: 255, B: 255, A: 1})
+	defaultWhiteImgTex, err := assets.LoadTextureInMemPngImg(defaultWhiteImg, &assets.TextureLoadOptions{NoSrgba: true})
+	if err != nil {
+		return err
+	}
+	assets.DefaultWhiteTexId = defaultWhiteImgTex
+
+	// Default diffuse
+	assets.DefaultDiffuseTexId = defaultWhiteImgTex
+
+	// Default specular
+	assets.DefaultSpecularTexId = defaultBlackImgTex
+
+	// Default Normal map which is created to be RGB(0.5,0.5,1), which when multiplied by TBN matrix gives the vertex normal.
+	// 128 is better than 127 for normal maps. See 'Flat Color' section here: http://wiki.polycount.com/wiki/Normal_map
+	// Basically, 127 can create seams while 128 looks correct
+	defaultNormalMapImg := image.NewNRGBA(image.Rect(0, 0, 1, 1))
+	defaultNormalMapImg.Set(0, 0, color.NRGBA{R: 128, G: 128, B: 255, A: 1})
+	defaultNormalMapTex, err := assets.LoadTextureInMemPngImg(defaultNormalMapImg, &assets.TextureLoadOptions{NoSrgba: true})
+	if err != nil {
+		return err
+	}
+
+	assets.DefaultNormalTexId = defaultNormalMapTex
+
+	// Default emission
+	assets.DefaultEmissionTexId = defaultBlackImgTex
+
+	assert.T(assets.DefaultBlackTexId.TexID != 0, "The default black texture handle is zero. Either texture wasn't created or handle wasn't updated")
+	assert.T(assets.DefaultWhiteTexId.TexID != 0, "The default white texture handle is zero. Either texture wasn't created or handle wasn't updated")
+	assert.T(assets.DefaultDiffuseTexId.TexID != 0, "The default diffuse texture handle is zero. Either texture wasn't created or handle wasn't updated")
+	assert.T(assets.DefaultSpecularTexId.TexID != 0, "The default specular texture handle is zero. Either texture wasn't created or handle wasn't updated")
+	assert.T(assets.DefaultNormalTexId.TexID != 0, "The default normal texture handle is zero. Either texture wasn't created or handle wasn't updated")
+	assert.T(assets.DefaultEmissionTexId.TexID != 0, "The default emission texture handle is zero. Either texture wasn't created or handle wasn't updated")
+
+	return nil
+}
+
 func SetSrgbFramebuffer(isEnabled bool) {
 
 	if isEnabled {

engine/game.go

@@ -1,6 +1,7 @@
 package engine
 
 import (
+	"github.com/bloeys/nmage/renderer"
 	"github.com/bloeys/nmage/timing"
 	nmageimgui "github.com/bloeys/nmage/ui/imgui"
 	"github.com/go-gl/gl/v4.1-core/gl"
@@ -20,7 +21,7 @@ type Game interface {
 	DeInit()
 }
 
-func Run(g Game, w *Window, ui nmageimgui.ImguiInfo) {
+func Run(g Game, w *Window, rend renderer.Render, ui nmageimgui.ImguiInfo) {
 
 	isRunning = true
 
@@ -56,7 +57,7 @@ func Run(g Game, w *Window, ui nmageimgui.ImguiInfo) {
 		w.SDLWin.GLSwap()
 
 		g.FrameEnd()
-		w.Rend.FrameEnd()
+		rend.FrameEnd()
 		timing.FrameEnded()
 	}
 

go.mod

@@ -8,7 +8,7 @@ require github.com/go-gl/gl v0.0.0-20211210172815-726fda9656d6
 
 require (
 	github.com/bloeys/assimp-go v0.4.4
-	github.com/bloeys/gglm v0.43.0
+	github.com/bloeys/gglm v0.49.0
 )
 
 require (

go.sum

@@ -2,8 +2,8 @@ github.com/AllenDang/cimgui-go v0.0.0-20230720025235-f2ff398a66b2 h1:3HA/5qD8Rim
 github.com/AllenDang/cimgui-go v0.0.0-20230720025235-f2ff398a66b2/go.mod h1:iNfbIyOBN8k3XScMxULbrwYbPsXEAUD0Jb6UwrspQb8=
 github.com/bloeys/assimp-go v0.4.4 h1:Yn5e/RpE0Oes0YMBy8O7KkwAO4R/RpgrZPJCt08dVIU=
 github.com/bloeys/assimp-go v0.4.4/go.mod h1:my3yRxT7CfOztmvi+0svmwbaqw0KFrxaHxncoyaEIP0=
-github.com/bloeys/gglm v0.43.0 h1:ZpOghR3PHfpkigTDh+FqxLsF0gN8CD6s/bWoei6LyxI=
+github.com/bloeys/gglm v0.49.0 h1:YtbyHpszYhjnxw7KVV0LaCdBktRMqfGx/i37EMomxsE=
-github.com/bloeys/gglm v0.43.0/go.mod h1:qwJQ0WzV191wAMwlGicbfbChbKoSedMk7gFFX6GnyOk=
+github.com/bloeys/gglm v0.49.0/go.mod h1:qwJQ0WzV191wAMwlGicbfbChbKoSedMk7gFFX6GnyOk=
 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/mandykoh/go-parallel v0.1.0 h1:7vJMNMC4dsbgZdkAb2A8tV5ENY1v7VxIO1wzQWZoT8k=

materials/material.go

@@ -1,13 +1,26 @@
 package materials
 
 import (
+	_ "unsafe"
+
 	"github.com/bloeys/gglm/gglm"
 	"github.com/bloeys/nmage/assert"
+	"github.com/bloeys/nmage/assets"
 	"github.com/bloeys/nmage/logging"
 	"github.com/bloeys/nmage/shaders"
 	"github.com/go-gl/gl/v4.1-core/gl"
 )
 
+// @TODO: This noescape magic is to avoid heap allocations done when
+// passing vectors or matrices into cgo via set uniform calls.
+//
+// But I would rather this kind of stuff is done on the gl wrapper level.
+// Should we wrap the OpenGL APIs we use ourself?
+
+var (
+	lastMatId uint32
+)
+
 type TextureSlot uint32
 
 const (
@@ -21,14 +34,36 @@ const (
 	TextureSlot_ShadowMap_Array1 TextureSlot = 13
 )
 
+type MaterialSettings uint64
+
+const (
+	MaterialSettings_None        MaterialSettings = iota
+	MaterialSettings_HasModelMtx MaterialSettings = 1 << (iota - 1)
+	MaterialSettings_HasNormalMtx
+)
+
+func (ms *MaterialSettings) Set(flags MaterialSettings) {
+	*ms |= flags
+}
+
+func (ms *MaterialSettings) Remove(flags MaterialSettings) {
+	*ms &= ^flags
+}
+
+func (ms *MaterialSettings) Has(flags MaterialSettings) bool {
+	return *ms&flags == flags
+}
+
 type Material struct {
+	Id         uint32
 	Name       string
 	ShaderProg shaders.ShaderProgram
+	Settings   MaterialSettings
 
 	UnifLocs   map[string]int32
 	AttribLocs map[string]int32
 
-	// @TODO do this in a better way. Perhaps something like how we do fbo attachments
+	// @TODO: Do this in a better way?. Perhaps something like how we do fbo attachments? Or keep it?
 	// Phong shading
 	DiffuseTex  uint32
 	SpecularTex uint32
@@ -51,26 +86,19 @@ func (m *Material) Bind() {
 
 	m.ShaderProg.Bind()
 
-	if m.DiffuseTex != 0 {
+	gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_Diffuse))
-		gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_Diffuse))
+	gl.BindTexture(gl.TEXTURE_2D, m.DiffuseTex)
-		gl.BindTexture(gl.TEXTURE_2D, m.DiffuseTex)
-	}
 
-	if m.SpecularTex != 0 {
+	gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_Specular))
-		gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_Specular))
+	gl.BindTexture(gl.TEXTURE_2D, m.SpecularTex)
-		gl.BindTexture(gl.TEXTURE_2D, m.SpecularTex)
-	}
 
-	if m.NormalTex != 0 {
+	gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_Normal))
-		gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_Normal))
+	gl.BindTexture(gl.TEXTURE_2D, m.NormalTex)
-		gl.BindTexture(gl.TEXTURE_2D, m.NormalTex)
-	}
 
-	if m.EmissionTex != 0 {
+	gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_Emission))
-		gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_Emission))
+	gl.BindTexture(gl.TEXTURE_2D, m.EmissionTex)
-		gl.BindTexture(gl.TEXTURE_2D, m.EmissionTex)
-	}
 
+	// @TODO: Have defaults for these
 	if m.CubemapTex != 0 {
 		gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_Cubemap))
 		gl.BindTexture(gl.TEXTURE_CUBE_MAP, m.CubemapTex)
@@ -139,49 +167,124 @@ func (m *Material) SetUnifFloat32(uniformName string, val float32) {
 }
 
 func (m *Material) SetUnifVec2(uniformName string, vec2 *gglm.Vec2) {
-	gl.ProgramUniform2fv(m.ShaderProg.Id, m.GetUnifLoc(uniformName), 1, &vec2.Data[0])
+	internalSetUnifVec2(m.ShaderProg.Id, m.GetUnifLoc(uniformName), vec2)
+}
+
+//go:noescape
+//go:linkname internalSetUnifVec2 github.com/bloeys/nmage/materials.SetUnifVec2
+func internalSetUnifVec2(shaderProgId uint32, unifLoc int32, vec2 *gglm.Vec2)
+
+func SetUnifVec2(shaderProgId uint32, unifLoc int32, vec2 *gglm.Vec2) {
+	gl.ProgramUniform2fv(shaderProgId, unifLoc, 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])
+	internalSetUnifVec3(m.ShaderProg.Id, m.GetUnifLoc(uniformName), vec3)
+}
+
+//go:noescape
+//go:linkname internalSetUnifVec3 github.com/bloeys/nmage/materials.SetUnifVec3
+func internalSetUnifVec3(shaderProgId uint32, unifLoc int32, vec3 *gglm.Vec3)
+
+func SetUnifVec3(shaderProgId uint32, unifLoc int32, vec3 *gglm.Vec3) {
+	gl.ProgramUniform3fv(shaderProgId, unifLoc, 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])
+	internalSetUnifVec4(m.ShaderProg.Id, m.GetUnifLoc(uniformName), vec4)
+}
+
+//go:noescape
+//go:linkname internalSetUnifVec4 github.com/bloeys/nmage/materials.SetUnifVec4
+func internalSetUnifVec4(shaderProgId uint32, unifLoc int32, vec4 *gglm.Vec4)
+
+func SetUnifVec4(shaderProgId uint32, unifLoc int32, vec4 *gglm.Vec4) {
+	gl.ProgramUniform4fv(shaderProgId, unifLoc, 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])
+	internalSetUnifMat2(m.ShaderProg.Id, m.GetUnifLoc(uniformName), mat2)
+}
+
+//go:noescape
+//go:linkname internalSetUnifMat2 github.com/bloeys/nmage/materials.SetUnifMat2
+func internalSetUnifMat2(shaderProgId uint32, unifLoc int32, mat2 *gglm.Mat2)
+
+func SetUnifMat2(shaderProgId uint32, unifLoc int32, mat2 *gglm.Mat2) {
+	gl.ProgramUniformMatrix2fv(shaderProgId, unifLoc, 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])
+	internalSetUnifMat3(m.ShaderProg.Id, m.GetUnifLoc(uniformName), mat3)
+}
+
+//go:noescape
+//go:linkname internalSetUnifMat3 github.com/bloeys/nmage/materials.SetUnifMat3
+func internalSetUnifMat3(shaderProgId uint32, unifLoc int32, mat3 *gglm.Mat3)
+
+func SetUnifMat3(shaderProgId uint32, unifLoc int32, mat3 *gglm.Mat3) {
+	gl.ProgramUniformMatrix3fv(shaderProgId, unifLoc, 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])
+	internalSetUnifMat4(m.ShaderProg.Id, m.GetUnifLoc(uniformName), mat4)
+}
+
+//go:noescape
+//go:linkname internalSetUnifMat4 github.com/bloeys/nmage/materials.SetUnifMat4
+func internalSetUnifMat4(shaderProgId uint32, unifLoc int32, mat4 *gglm.Mat4)
+
+func SetUnifMat4(shaderProgId uint32, unifLoc int32, mat4 *gglm.Mat4) {
+	gl.ProgramUniformMatrix4fv(shaderProgId, unifLoc, 1, false, &mat4.Data[0][0])
 }
 
 func (m *Material) Delete() {
 	gl.DeleteProgram(m.ShaderProg.Id)
 }
 
-func NewMaterial(matName, shaderPath string) *Material {
+func getNewMatId() uint32 {
+	lastMatId++
+	return lastMatId
+}
+
+func NewMaterial(matName, shaderPath string) Material {
 
 	shdrProg, err := shaders.LoadAndCompileCombinedShader(shaderPath)
 	if err != nil {
 		logging.ErrLog.Fatalf("Failed to create new material '%s'. Err: %s\n", matName, err.Error())
 	}
 
-	return &Material{Name: matName, ShaderProg: shdrProg, UnifLocs: make(map[string]int32), AttribLocs: make(map[string]int32)}
+	return Material{
+		Id:         getNewMatId(),
+		Name:       matName,
+		ShaderProg: shdrProg,
+		UnifLocs:   make(map[string]int32),
+		AttribLocs: make(map[string]int32),
+
+		DiffuseTex:  assets.DefaultDiffuseTexId.TexID,
+		SpecularTex: assets.DefaultSpecularTexId.TexID,
+		NormalTex:   assets.DefaultNormalTexId.TexID,
+		EmissionTex: assets.DefaultEmissionTexId.TexID,
+	}
 }
 
-func NewMaterialSrc(matName string, shaderSrc []byte) *Material {
+func NewMaterialSrc(matName string, shaderSrc []byte) Material {
 
 	shdrProg, err := shaders.LoadAndCompileCombinedShaderSrc(shaderSrc)
 	if err != nil {
 		logging.ErrLog.Fatalf("Failed to create new material '%s'. Err: %s\n", matName, err.Error())
 	}
 
-	return &Material{Name: matName, ShaderProg: shdrProg, UnifLocs: make(map[string]int32), AttribLocs: make(map[string]int32)}
+	return Material{
+		Id:         getNewMatId(),
+		Name:       matName,
+		ShaderProg: shdrProg,
+		UnifLocs:   make(map[string]int32),
+		AttribLocs: make(map[string]int32),
+
+		DiffuseTex:  assets.DefaultDiffuseTexId.TexID,
+		SpecularTex: assets.DefaultSpecularTexId.TexID,
+		NormalTex:   assets.DefaultNormalTexId.TexID,
+		EmissionTex: assets.DefaultEmissionTexId.TexID,
+	}
 }

meshes/mesh.go

@@ -16,24 +16,48 @@ type SubMesh struct {
 }
 
 type Mesh struct {
-	Name      string
+	Name string
+	/*
+		Vao has the following shader attribute layout:
+			- Loc0: Pos
+			- Loc1: Normal
+			- Loc2: UV0
+			- Loc3: Tangent
+			- (Optional) Color
+
+		Optional stuff appear in the order in this list, depending on what other optional stuff exists.
+
+		For example:
+			- If color exists it will be in Loc3, otherwise it is unset
+	*/
 	Vao       buffers.VertexArray
 	SubMeshes []SubMesh
 }
 
-func NewMesh(name, modelPath string, postProcessFlags asig.PostProcess) (*Mesh, error) {
+var (
+	// DefaultMeshLoadFlags are the flags always applied when loading a new mesh regardless
+	// of what post process flags are used when loading a mesh.
+	//
+	// Defaults to: asig.PostProcessTriangulate | asig.PostProcessCalcTangentSpace;
+	// Note: changing this will break the normal lit shaders, which expect tangents to be there
+	DefaultMeshLoadFlags asig.PostProcess = asig.PostProcessTriangulate | asig.PostProcessCalcTangentSpace
+)
 
-	scene, release, err := asig.ImportFile(modelPath, asig.PostProcessTriangulate|postProcessFlags)
+func NewMesh(name, modelPath string, postProcessFlags asig.PostProcess) (Mesh, error) {
+
+	finalPostProcessFlags := DefaultMeshLoadFlags | postProcessFlags
+
+	scene, release, err := asig.ImportFile(modelPath, finalPostProcessFlags)
 	if err != nil {
-		return nil, errors.New("Failed to load model. Err: " + err.Error())
+		return Mesh{}, 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)
+		return Mesh{}, errors.New("No meshes found in file: " + modelPath)
 	}
 
-	mesh := &Mesh{
+	mesh := Mesh{
 		Name:      name,
 		Vao:       buffers.NewVertexArray(),
 		SubMeshes: make([]SubMesh, 0, 1),
@@ -42,8 +66,17 @@ func NewMesh(name, modelPath string, postProcessFlags asig.PostProcess) (*Mesh,
 	vbo := buffers.NewVertexBuffer()
 	ibo := buffers.NewIndexBuffer()
 
-	// Initial sizes assuming one submesh that has vertex pos+normals+texCoords, and 3 indices per face
+	// Estimate a useful prealloc capacity based on the first submesh that has vertex pos+normals+tangents+texCoords
-	var vertexBufData []float32 = make([]float32, 0, len(scene.Meshes[0].Vertices)*3*3*2)
+	vertexBufDataCapacity := len(scene.Meshes[0].Vertices) * 3 * 3 * 3 * 2
+
+	// Increase capacity depending on what the mesh has
+	if len(scene.Meshes[0].ColorSets) > 0 && len(scene.Meshes[0].ColorSets[0]) > 0 {
+		vertexBufDataCapacity *= 4
+	}
+
+	var vertexBufData []float32 = make([]float32, 0, vertexBufDataCapacity)
+
+	// Initial size assumes 3 indices per face
 	var indexBufData []uint32 = make([]uint32, 0, len(scene.Meshes[0].Faces)*3)
 
 	// fmt.Printf("\nMesh %s has %d meshe(s) with first mesh having %d vertices\n", name, len(scene.Meshes), len(scene.Meshes[0].Vertices))
@@ -52,12 +85,25 @@ func NewMesh(name, modelPath string, postProcessFlags asig.PostProcess) (*Mesh,
 
 		sceneMesh := scene.Meshes[i]
 
+		// We always want tangents and UV0
+		if len(sceneMesh.Tangents) == 0 {
+			sceneMesh.Tangents = make([]gglm.Vec3, len(sceneMesh.Vertices))
+		}
+
 		if len(sceneMesh.TexCoords[0]) == 0 {
 			sceneMesh.TexCoords[0] = make([]gglm.Vec3, len(sceneMesh.Vertices))
 		}
 
-		layoutToUse := []buffers.Element{{ElementType: buffers.DataTypeVec3}, {ElementType: buffers.DataTypeVec3}, {ElementType: buffers.DataTypeVec2}}
+		hasColorSet0 := len(sceneMesh.ColorSets) > 0 && len(sceneMesh.ColorSets[0]) > 0
-		if len(sceneMesh.ColorSets) > 0 && len(sceneMesh.ColorSets[0]) > 0 {
+
+		layoutToUse := []buffers.Element{
+			{ElementType: buffers.DataTypeVec3}, // Position
+			{ElementType: buffers.DataTypeVec3}, // Normals
+			{ElementType: buffers.DataTypeVec3}, // Tangents
+			{ElementType: buffers.DataTypeVec2}, // UV0
+		}
+
+		if hasColorSet0 {
 			layoutToUse = append(layoutToUse, buffers.Element{ElementType: buffers.DataTypeVec4})
 		}
 
@@ -79,8 +125,14 @@ func NewMesh(name, modelPath string, postProcessFlags asig.PostProcess) (*Mesh,
 			}
 		}
 
-		arrs := []arrToInterleave{{V3s: sceneMesh.Vertices}, {V3s: sceneMesh.Normals}, {V2s: v3sToV2s(sceneMesh.TexCoords[0])}}
+		arrs := []arrToInterleave{
-		if len(sceneMesh.ColorSets) > 0 && len(sceneMesh.ColorSets[0]) > 0 {
+			{V3s: sceneMesh.Vertices},
+			{V3s: sceneMesh.Normals},
+			{V3s: sceneMesh.Tangents},
+			{V2s: v3sToV2s(sceneMesh.TexCoords[0])},
+		}
+
+		if hasColorSet0 {
 			arrs = append(arrs, arrToInterleave{V4s: sceneMesh.ColorSets[0]})
 		}
 

renderer/rend3dgl/rend3dgl.go

@@ -12,24 +12,31 @@ import (
 var _ renderer.Render = &Rend3DGL{}
 
 type Rend3DGL struct {
-	BoundVao  *buffers.VertexArray
+	BoundVaoId     uint32
-	BoundMesh *meshes.Mesh
+	BoundMatId     uint32
-	BoundMat  *materials.Material
+	BoundMeshVaoId uint32
 }
 
 func (r *Rend3DGL) DrawMesh(mesh *meshes.Mesh, modelMat *gglm.TrMat, mat *materials.Material) {
 
-	if mesh != r.BoundMesh {
+	if mesh.Vao.Id != r.BoundMeshVaoId {
 		mesh.Vao.Bind()
-		r.BoundMesh = mesh
+		r.BoundMeshVaoId = mesh.Vao.Id
 	}
 
-	if mat != r.BoundMat {
+	if mat.Id != r.BoundMatId {
 		mat.Bind()
-		r.BoundMat = mat
+		r.BoundMatId = mat.Id
 	}
 
-	mat.SetUnifMat4("modelMat", &modelMat.Mat4)
+	if mat.Settings.Has(materials.MaterialSettings_HasModelMtx) {
+		mat.SetUnifMat4("modelMat", &modelMat.Mat4)
+	}
+
+	if mat.Settings.Has(materials.MaterialSettings_HasNormalMtx) {
+		normalMat := modelMat.Clone().InvertAndTranspose().ToMat3()
+		mat.SetUnifMat3("normalMat", &normalMat)
+	}
 
 	for i := 0; i < len(mesh.SubMeshes); i++ {
 		gl.DrawElementsBaseVertexWithOffset(gl.TRIANGLES, mesh.SubMeshes[i].IndexCount, gl.UNSIGNED_INT, uintptr(mesh.SubMeshes[i].BaseIndex), mesh.SubMeshes[i].BaseVertex)
@@ -38,14 +45,14 @@ func (r *Rend3DGL) DrawMesh(mesh *meshes.Mesh, modelMat *gglm.TrMat, mat *materi
 
 func (r *Rend3DGL) DrawVertexArray(mat *materials.Material, vao *buffers.VertexArray, firstElement int32, elementCount int32) {
 
-	if vao != r.BoundVao {
+	if vao.Id != r.BoundVaoId {
 		vao.Bind()
-		r.BoundVao = vao
+		r.BoundVaoId = vao.Id
 	}
 
-	if mat != r.BoundMat {
+	if mat.Id != r.BoundMatId {
 		mat.Bind()
-		r.BoundMat = mat
+		r.BoundMatId = mat.Id
 	}
 
 	gl.DrawArrays(gl.TRIANGLES, firstElement, elementCount)
@@ -53,14 +60,14 @@ func (r *Rend3DGL) DrawVertexArray(mat *materials.Material, vao *buffers.VertexA
 
 func (r *Rend3DGL) DrawCubemap(mesh *meshes.Mesh, mat *materials.Material) {
 
-	if mesh != r.BoundMesh {
+	if mesh.Vao.Id != r.BoundMeshVaoId {
 		mesh.Vao.Bind()
-		r.BoundMesh = mesh
+		r.BoundMeshVaoId = mesh.Vao.Id
 	}
 
-	if mat != r.BoundMat {
+	if mat.Id != r.BoundMatId {
 		mat.Bind()
-		r.BoundMat = mat
+		r.BoundMatId = mat.Id
 	}
 
 	for i := 0; i < len(mesh.SubMeshes); i++ {
@@ -69,8 +76,9 @@ func (r *Rend3DGL) DrawCubemap(mesh *meshes.Mesh, mat *materials.Material) {
 }
 
 func (r3d *Rend3DGL) FrameEnd() {
-	r3d.BoundMesh = nil
+	r3d.BoundVaoId = 0
-	r3d.BoundMat = nil
+	r3d.BoundMatId = 0
+	r3d.BoundMeshVaoId = 0
 }
 
 func NewRend3DGL() *Rend3DGL {

res/shaders/debug-depth.glsl

@@ -2,22 +2,19 @@
 #version 410
 
 layout(location=0) in vec3 vertPosIn;
-layout(location=1) in vec3 vertNormalIn;
+layout(location=2) in vec3 vertTangentIn;
-layout(location=2) in vec2 vertUV0In;
+layout(location=3) in vec2 vertUV0In;
-layout(location=3) in vec3 vertColorIn;
+layout(location=4) in vec3 vertColorIn;
 
-out vec3 vertNormal;
 out vec2 vertUV0;
 out vec3 vertColor;
 out vec3 fragPos;
 
-//MVP = Model View Projection
 uniform mat4 modelMat;
 uniform mat4 projViewMat;
 
 void main()
 {
-    vertNormal = mat3(transpose(inverse(modelMat))) * vertNormalIn;
     vertUV0 = vertUV0In;
     vertColor = vertColorIn;
 
@@ -31,7 +28,6 @@ void main()
 #version 410
 
 in vec3 vertColor;
-in vec3 vertNormal;
 in vec2 vertUV0;
 in vec3 fragPos;
 

res/shaders/simple-unlit.glsl

@@ -3,26 +3,19 @@
 
 layout(location=0) in vec3 vertPosIn;
 layout(location=1) in vec3 vertNormalIn;
-layout(location=2) in vec2 vertUV0In;
+layout(location=2) in vec3 vertTangentIn;
-layout(location=3) in vec3 vertColorIn;
+layout(location=3) in vec2 vertUV0In;
+layout(location=4) in vec3 vertColorIn;
 
-out vec3 vertNormal;
 out vec2 vertUV0;
 out vec3 vertColor;
 out vec3 fragPos;
 
-//MVP = Model View Projection
 uniform mat4 modelMat;
 uniform mat4 projViewMat;
 
 void main()
 {
-    // @TODO: Calculate this on the CPU and send it as a uniform
-    //
-    // This produces the normal matrix that multiplies with the model normal to produce the
-    // world space normal. Based on 'One last thing' section from: https://learnopengl.com/Lighting/Basic-Lighting
-    vertNormal = mat3(transpose(inverse(modelMat))) * vertNormalIn;
-    
     vertUV0 = vertUV0In;
     vertColor = vertColorIn;
 
@@ -41,7 +34,6 @@ struct Material {
 uniform Material material;
 
 in vec3 vertColor;
-in vec3 vertNormal;
 in vec2 vertUV0;
 in vec3 fragPos;
 

res/shaders/simple.glsl

@@ -1,66 +1,34 @@
 //shader:vertex
 #version 410
 
+#define NUM_SPOT_LIGHTS 4
+#define NUM_POINT_LIGHTS 8
+
+//
+// Inputs
+//
 layout(location=0) in vec3 vertPosIn;
 layout(location=1) in vec3 vertNormalIn;
-layout(location=2) in vec2 vertUV0In;
+layout(location=2) in vec3 vertTangentIn;
-layout(location=3) in vec3 vertColorIn;
+layout(location=3) in vec2 vertUV0In;
+layout(location=4) in vec3 vertColorIn;
 
+//
+// Uniforms
+//
+uniform vec3 camPos;
 uniform mat4 modelMat;
+uniform mat3 normalMat;
 uniform mat4 projViewMat;
 uniform mat4 dirLightProjViewMat;
-
-#define NUM_SPOT_LIGHTS 4
 uniform mat4 spotLightProjViewMats[NUM_SPOT_LIGHTS];
 
-out vec3 vertNormal;
-out vec2 vertUV0;
-out vec3 vertColor;
-out vec3 fragPos;
-out vec4 fragPosDirLight;
-out vec4 fragPosSpotLight[NUM_SPOT_LIGHTS];
-
-void main()
-{
-    // @TODO: Calculate this on the CPU and send it as a uniform
-    //
-    // This produces the normal matrix that multiplies with the model normal to produce the
-    // world space normal. Based on 'One last thing' section from: https://learnopengl.com/Lighting/Basic-Lighting
-    vertNormal = mat3(transpose(inverse(modelMat))) * vertNormalIn;
-    
-    vertUV0 = vertUV0In;
-    vertColor = vertColorIn;
-
-    vec4 modelVert = modelMat * vec4(vertPosIn, 1);
-    fragPos = modelVert.xyz;
-    fragPosDirLight = dirLightProjViewMat * vec4(fragPos, 1);
-
-    for (int i = 0; i < NUM_SPOT_LIGHTS; i++)
-        fragPosSpotLight[i] = spotLightProjViewMats[i] * vec4(fragPos, 1);
-
-    gl_Position = projViewMat * modelVert;
-}
-
-//shader:fragment
-#version 410
-
-struct Material {
-    sampler2D diffuse;
-    sampler2D specular;
-    // sampler2D normal;
-    sampler2D emission;
-    float shininess;
-};
-
-uniform Material material;
-
 struct DirLight {
     vec3 dir;
     vec3 diffuseColor;
     vec3 specularColor;
     sampler2D shadowMap;
 };
-
 uniform DirLight dirLight;
 
 struct PointLight {
@@ -72,8 +40,133 @@ struct PointLight {
     float quadratic;
     float farPlane;
 };
+uniform PointLight pointLights[NUM_POINT_LIGHTS];
 
+struct SpotLight {
+    vec3 pos;
+    vec3 dir;
+    vec3 diffuseColor;
+    vec3 specularColor;
+    float innerCutoff;
+    float outerCutoff;
+};
+uniform SpotLight spotLights[NUM_SPOT_LIGHTS];
+
+//
+// Outputs
+//
+out vec2 vertUV0;
+out vec3 vertColor;
+
+out vec3 fragPos;
+out vec3 fragPosDirLight;
+out vec4 fragPosSpotLight[NUM_SPOT_LIGHTS];
+
+out vec3 tangentCamPos;
+out vec3 tangentFragPos;
+out vec3 tangentDirLightDir;
+out vec3 tangentSpotLightPositions[NUM_SPOT_LIGHTS];
+out vec3 tangentSpotLightDirections[NUM_SPOT_LIGHTS];
+out vec3 tangentPointLightPositions[NUM_POINT_LIGHTS];
+
+void main()
+{
+    vertUV0 = vertUV0In;
+    vertColor = vertColorIn;
+    vec4 modelVert = modelMat * vec4(vertPosIn, 1);
+
+    // Tangent-BiTangent-Normal matrix for normal mapping
+    vec3 T = normalize(vec3(modelMat * vec4(vertTangentIn,   0.0)));
+    vec3 N = normalize(vec3(modelMat * vec4(vertNormalIn,    0.0)));
+
+    // Ensure T is orthogonal with respect to N
+    T = normalize(T - dot(T, N) * N);
+
+    vec3 B = cross(N, T);
+    mat3 tbnMtx = transpose(mat3(T, B, N));
+
+    // Lighting related
+    fragPos = modelVert.xyz;
+    fragPosDirLight = vec3(dirLightProjViewMat * vec4(fragPos, 1));
+
+    tangentCamPos = tbnMtx * camPos;
+    tangentFragPos = tbnMtx * fragPos;
+    tangentDirLightDir = tbnMtx * dirLight.dir;
+
+    for (int i = 0; i < NUM_POINT_LIGHTS; i++)
+        tangentPointLightPositions[i] = tbnMtx * pointLights[i].pos;
+
+    for (int i = 0; i < NUM_SPOT_LIGHTS; i++)
+    {
+        fragPosSpotLight[i] = spotLightProjViewMats[i] * vec4(fragPos, 1);
+
+        tangentSpotLightPositions[i] = tbnMtx * spotLights[i].pos;
+        tangentSpotLightDirections[i] = tbnMtx * spotLights[i].dir;
+    }
+
+    gl_Position = projViewMat * modelVert;
+}
+
+//shader:fragment
+#version 410
+
+/*
+    Note that while all lighting calculations are done in tangent space,
+    shadow mapping is done in world space.
+
+    The exception is the bias calculation. Since the bias relies on the normal
+    and the normal is in tangent space, we use a tangent space fragment position
+    with it, but the rest of shadow processing is in world space.
+*/
+
+#define NUM_SPOT_LIGHTS 4
 #define NUM_POINT_LIGHTS 8
+
+//
+// Inputs
+//
+in vec3 fragPos;
+in vec2 vertUV0;
+in vec3 vertColor;
+in vec3 fragPosDirLight;
+in vec4 fragPosSpotLight[NUM_SPOT_LIGHTS];
+
+in vec3 tangentCamPos;
+in vec3 tangentFragPos;
+in vec3 tangentDirLightDir;
+in vec3 tangentSpotLightPositions[NUM_SPOT_LIGHTS];
+in vec3 tangentSpotLightDirections[NUM_SPOT_LIGHTS];
+in vec3 tangentPointLightPositions[NUM_POINT_LIGHTS];
+
+//
+// Uniforms
+//
+struct Material {
+    sampler2D diffuse;
+    sampler2D specular;
+    sampler2D normal;
+    sampler2D emission;
+    float shininess;
+};
+uniform Material material;
+
+struct DirLight {
+    vec3 dir;
+    vec3 diffuseColor;
+    vec3 specularColor;
+    sampler2D shadowMap;
+};
+uniform DirLight dirLight;
+
+struct PointLight {
+    vec3 pos;
+    vec3 diffuseColor;
+    vec3 specularColor;
+    float constant;
+    float linear;
+    float quadratic;
+    float farPlane;
+};
 uniform PointLight pointLights[NUM_POINT_LIGHTS];
 uniform samplerCubeArray pointLightCubeShadowMaps;
 
@@ -85,37 +178,29 @@ struct SpotLight {
     float innerCutoff;
     float outerCutoff;
 };
-
-#define NUM_SPOT_LIGHTS 4
 uniform SpotLight spotLights[NUM_SPOT_LIGHTS];
 uniform sampler2DArray spotLightShadowMaps;
 
-uniform vec3 camPos;
 uniform vec3 ambientColor = vec3(0.2, 0.2, 0.2);
 
-in vec3 vertColor;
+//
-in vec3 vertNormal;
+// Outputs
-in vec2 vertUV0;
+//
-in vec3 fragPos;
-in vec4 fragPosDirLight;
-in vec4 fragPosSpotLight[NUM_SPOT_LIGHTS];
-
 out vec4 fragColor;
 
+//
 // Global variables used as cache for lighting calculations
+//
+vec3 tangentViewDir;
 vec4 diffuseTexColor;
 vec4 specularTexColor;
 vec4 emissionTexColor;
 vec3 normalizedVertNorm;
-vec3 viewDir;
 
-float CalcDirShadow(sampler2D shadowMap, vec3 lightDir)
+float CalcDirShadow(sampler2D shadowMap, vec3 tangentLightDir)
 {
-    // Move from clip space to NDC
-    vec3 projCoords = fragPosDirLight.xyz / fragPosDirLight.w;
-
     // Move from [-1,1] to [0, 1]
-    projCoords = projCoords * 0.5 + 0.5;
+    vec3 projCoords = fragPosDirLight * 0.5 + 0.5;
 
     // If sampling outside the depth texture then force 'no shadow'
     if(projCoords.z > 1)
@@ -126,7 +211,7 @@ float CalcDirShadow(sampler2D shadowMap, vec3 lightDir)
 
     // Bias in the range [0.005, 0.05] depending on the angle, where a higher
     // angle gives a higher bias, as shadow acne gets worse with angle
-    float bias = max(0.05 * (1 - dot(normalizedVertNorm, lightDir)), 0.005);
+    float bias = max(0.05 * (1 - dot(normalizedVertNorm, tangentLightDir)), 0.005);
 
     // 'Percentage Close Filtering'.
     // Basically get soft shadows by averaging this texel and surrounding ones
@@ -151,14 +236,14 @@ float CalcDirShadow(sampler2D shadowMap, vec3 lightDir)
 
 vec3 CalcDirLight()
 {
-    vec3 lightDir = normalize(-dirLight.dir);
+    vec3 lightDir = normalize(-tangentDirLightDir);
 
     // Diffuse
     float diffuseAmount = max(0.0, dot(normalizedVertNorm, lightDir));
     vec3 finalDiffuse = diffuseAmount * dirLight.diffuseColor * diffuseTexColor.rgb;
 
     // Specular
-    vec3 halfwayDir = normalize(lightDir + viewDir);
+    vec3 halfwayDir = normalize(lightDir + tangentViewDir);
     float specularAmount = pow(max(dot(normalizedVertNorm, halfwayDir), 0.0), material.shininess);
     vec3 finalSpecular = specularAmount * dirLight.specularColor * specularTexColor.rgb;
 
@@ -168,9 +253,9 @@ vec3 CalcDirLight()
     return (finalDiffuse + finalSpecular) * (1 - shadow);
 }
 
-float CalcPointShadow(int lightIndex, vec3 lightPos, vec3 lightDir, float farPlane) {
+float CalcPointShadow(int lightIndex, vec3 worldLightPos, vec3 tangentLightDir, float farPlane) {
 
-    vec3 lightToFrag = fragPos - lightPos;
+    vec3 lightToFrag = fragPos - worldLightPos;
 
     float closestDepth = texture(pointLightCubeShadowMaps, vec4(lightToFrag, lightIndex)).r;
 
@@ -180,7 +265,8 @@ float CalcPointShadow(int lightIndex, vec3 lightPos, vec3 lightDir, float farPla
     // Get depth of current fragment
     float currentDepth = length(lightToFrag);
 
-    float bias = max(0.05 * (1 - dot(normalizedVertNorm, lightDir)), 0.005);
+    float bias = max(0.05 * (1 - dot(normalizedVertNorm, tangentLightDir)), 0.005);
+
     float shadow = currentDepth -  bias > closestDepth ? 1.0 : 0.0;
 
     return shadow;
@@ -193,28 +279,29 @@ vec3 CalcPointLight(PointLight pointLight, int lightIndex)
         return vec3(0);
     }
 
-    vec3 lightDir = normalize(pointLight.pos - fragPos);
+    vec3 tangentLightPos = tangentPointLightPositions[lightIndex];
+    vec3 tangentLightDir = normalize(tangentLightPos - tangentFragPos);
 
     // Diffuse
-    float diffuseAmount = max(0.0, dot(normalizedVertNorm, lightDir));
+    float diffuseAmount = max(0.0, dot(normalizedVertNorm, tangentLightDir));
     vec3 finalDiffuse = diffuseAmount * pointLight.diffuseColor * diffuseTexColor.rgb;
 
     // Specular
-    vec3 halfwayDir = normalize(lightDir + viewDir);
+    vec3 halfwayDir = normalize(tangentLightDir + tangentViewDir);
     float specularAmount = pow(max(dot(normalizedVertNorm, halfwayDir), 0.0), material.shininess);
     vec3 finalSpecular = specularAmount * pointLight.specularColor * specularTexColor.rgb;
 
     // Attenuation
-    float distToLight = length(pointLight.pos - fragPos);
+    float distToLight = length(tangentLightPos - tangentFragPos);
     float attenuation = 1 / (pointLight.constant + pointLight.linear * distToLight + pointLight.quadratic * (distToLight * distToLight));  
 
     // Shadow
-    float shadow = CalcPointShadow(lightIndex, pointLight.pos, lightDir, pointLight.farPlane);
+    float shadow = CalcPointShadow(lightIndex, pointLight.pos, tangentLightDir, pointLight.farPlane);
 
     return (finalDiffuse + finalSpecular) * attenuation * (1 - shadow);
 }
 
-float CalcSpotShadow(vec3 lightDir, int lightIndex)
+float CalcSpotShadow(vec3 tangentLightDir, int lightIndex)
 {
     // Move from clip space to NDC
     vec3 projCoords = fragPosSpotLight[lightIndex].xyz / fragPosSpotLight[lightIndex].w;
@@ -231,7 +318,7 @@ float CalcSpotShadow(vec3 lightDir, int lightIndex)
 
     // Bias in the range [0.005, 0.05] depending on the angle, where a higher
     // angle gives a higher bias, as shadow acne gets worse with angle
-    float bias = max(0.05 * (1 - dot(normalizedVertNorm, lightDir)), 0.005);
+    float bias = max(0.05 * (1 - dot(normalizedVertNorm, tangentLightDir)), 0.005);
 
     // 'Percentage Close Filtering'.
     // Basically get soft shadows by averaging this texel and surrounding ones
@@ -259,12 +346,13 @@ vec3 CalcSpotLight(SpotLight light, int lightIndex)
     if (light.innerCutoff == 0)
         return vec3(0);
 
-    vec3 fragToLightDir = normalize(light.pos - fragPos);
+    vec3 tangentLightDir = tangentSpotLightDirections[lightIndex];
+    vec3 fragToLightDir = normalize(tangentSpotLightPositions[lightIndex] - tangentFragPos);
 
     // Spot light cone with full intensity within inner cutoff,
     // and falloff between inner-outer cutoffs, and zero
     // light after outer cutoff
-    float theta = dot(fragToLightDir, normalize(-light.dir));
+    float theta = dot(fragToLightDir, normalize(-tangentLightDir));
     float epsilon = (light.innerCutoff - light.outerCutoff);
     float intensity = clamp((theta - light.outerCutoff) / epsilon, float(0), float(1));
 
@@ -276,7 +364,7 @@ vec3 CalcSpotLight(SpotLight light, int lightIndex)
     vec3 finalDiffuse = diffuseAmount * light.diffuseColor * diffuseTexColor.rgb;
 
     // Specular
-    vec3 halfwayDir = normalize(fragToLightDir + viewDir);
+    vec3 halfwayDir = normalize(fragToLightDir + tangentViewDir);
     float specularAmount = pow(max(dot(normalizedVertNorm, halfwayDir), 0.0), material.shininess);
     vec3 finalSpecular = specularAmount * light.specularColor * specularTexColor.rgb;
 
@@ -286,15 +374,21 @@ vec3 CalcSpotLight(SpotLight light, int lightIndex)
     return (finalDiffuse + finalSpecular) * intensity * (1 - shadow);
 }
 
+#define DRAW_NORMALS false
+
 void main()
 {
     // Shared values
+    tangentViewDir = normalize(tangentCamPos - tangentFragPos);
     diffuseTexColor = texture(material.diffuse, vertUV0);
     specularTexColor = texture(material.specular, vertUV0);
     emissionTexColor = texture(material.emission, vertUV0);
 
-    normalizedVertNorm = normalize(vertNormal);
+    // Read normal data encoded [0,1]
-    viewDir = normalize(camPos - fragPos);
+    normalizedVertNorm = texture(material.normal, vertUV0).rgb;
+
+    // Remap normal to [-1,1]
+    normalizedVertNorm = normalize(normalizedVertNorm * 2.0 - 1.0);
 
     // Light contributions
     vec3 finalColor = CalcDirLight();
@@ -313,4 +407,9 @@ void main()
     vec3 finalAmbient = ambientColor * diffuseTexColor.rgb;
 
     fragColor = vec4(finalColor + finalAmbient + finalEmission, 1);
+
+    if (DRAW_NORMALS)
+    {
+        fragColor = vec4(texture(material.normal, vertUV0).rgb, 1);
+    }
 }

res/shaders/skybox.glsl

@@ -3,8 +3,9 @@
 
 layout(location=0) in vec3 vertPosIn;
 layout(location=1) in vec3 vertNormalIn;
-layout(location=2) in vec2 vertUV0In;
+layout(location=2) in vec3 vertTangentIn;
-layout(location=3) in vec3 vertColorIn;
+layout(location=3) in vec2 vertUV0In;
+layout(location=4) in vec3 vertColorIn;
 
 out vec3 vertUV0;
 

res/shaders/tonemapped-screen-quad.glsl

@@ -0,0 +1,50 @@
+//shader:vertex
+#version 410
+
+out vec2 vertUV0;
+
+// Hardcoded vertex positions for a fullscreen quad.
+// Format: vec4(pos.x, pos.y, uv0.x, uv0.y)
+vec4 quadData[6] = vec4[](
+    vec4(-1.0,  1.0, 0.0, 1.0),
+    vec4(-1.0, -1.0, 0.0, 0.0),
+    vec4(1.0, -1.0, 1.0, 0.0),
+    vec4(-1.0,  1.0, 0.0, 1.0),
+    vec4(1.0, -1.0, 1.0, 0.0),
+    vec4(1.0,  1.0, 1.0, 1.0)
+);
+
+void main()
+{
+    vec4 vertData = quadData[gl_VertexID];
+
+    vertUV0 = vertData.zw;
+    gl_Position = vec4(vertData.xy, 0.0, 1.0);
+}
+
+//shader:fragment
+#version 410
+
+struct Material {
+    sampler2D diffuse;
+};
+
+uniform float exposure = 1;
+uniform Material material;
+
+in vec2 vertUV0;
+
+out vec4 fragColor;
+
+void main()
+{
+    vec4 diffuseTexColor = texture(material.diffuse, vertUV0);
+
+    // Reinhard tone mapping
+    // vec3 mappedColor = diffuseTexColor.rgb / (diffuseTexColor.rgb + vec3(1.0));
+
+    // Exposure tone mapping
+    vec3 mappedColor = vec3(1.0) - exp(-diffuseTexColor.rgb * exposure);
+
+    fragColor = vec4(mappedColor, 1);
+}

ui/imgui/imgui.go

@@ -12,7 +12,7 @@ import (
 type ImguiInfo struct {
 	ImCtx imgui.Context
 
-	Mat        *materials.Material
+	Mat        materials.Material
 	VaoID      uint32
 	VboID      uint32
 	IndexBufID uint32
@@ -204,7 +204,7 @@ void main()
 // If the path is empty a default nMage shader is used
 func NewImGui(shaderPath string) ImguiInfo {
 
-	var imguiMat *materials.Material
+	var imguiMat materials.Material
 	if shaderPath == "" {
 		imguiMat = materials.NewMaterialSrc("ImGUI Mat", []byte(DefaultImguiShader))
 	} else {