After all why not, why shouldn't we have HDR

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)

main.go

@@ -36,9 +36,10 @@ import (
 		- Point light shadows ✅
 		- Spotlight shadows ✅
 		- Create VAO struct independent from VBO to support multi-VBO use cases (e.g. instancing) ✅
-		- Normals maps
+		- Normals maps ✅
+		- HDR ✅
+		- Fix bad point light acne
 		- UBO support
-		- HDR
 		- Cascaded shadow mapping
 		- Skeletal animations
 	- In some cases we DO want input even when captured by UI. We need two systems within input package, one filtered and one not✅
@@ -202,12 +203,13 @@ var (
 	yaw   float32 = -1.5
 	cam   camera.Camera
 
-	// Demo fbo
-	renderToDemoFbo    = false
 	renderToBackBuffer = true
-	demoFboScale       = gglm.NewVec2(0.25, 0.25)
-	demoFboOffset      = gglm.NewVec2(0.75, -0.75)
-	demoFbo            buffers.Framebuffer
+
+	// Demo fbo
+	renderToDemoFbo = false
+	demoFboScale    = gglm.NewVec2(0.25, 0.25)
+	demoFboOffset   = gglm.NewVec2(0.75, -0.75)
+	demoFbo         buffers.Framebuffer
 
 	// Dir light fbo
 	showDirLightDepthMapFbo   = false
@@ -221,6 +223,12 @@ var (
 	// Spot light fbo
 	spotLightDepthMapFbo buffers.Framebuffer
 
+	// Hdr Fbo
+	hdrRendering                    = true
+	hdrExposure             float32 = 1
+	tonemappedScreenQuadMat materials.Material
+	hdrFbo                  buffers.Framebuffer
+
 	screenQuadVao buffers.VertexArray
 	screenQuadMat materials.Material
 
@@ -243,7 +251,7 @@ var (
 	cubeModelMat = gglm.NewTrMatId()
 
 	renderSkybox      = true
-	renderDepthBuffer bool
+	renderDepthBuffer = false
 
 	skyboxCmap assets.Cubemap
 
@@ -518,6 +526,9 @@ func (g *Game) Init() {
 	screenQuadMat.SetUnifVec2("offset", &demoFboOffset)
 	screenQuadMat.SetUnifInt32("material.diffuse", int32(materials.TextureSlot_Diffuse))
 
+	tonemappedScreenQuadMat = materials.NewMaterial("Tonemapped Screen Quad Mat", "./res/shaders/tonemapped-screen-quad.glsl")
+	tonemappedScreenQuadMat.SetUnifInt32("material.diffuse", int32(materials.TextureSlot_Diffuse))
+
 	unlitMat = materials.NewMaterial("Unlit mat", "./res/shaders/simple-unlit.glsl")
 	unlitMat.Settings.Set(materials.MaterialSettings_HasModelMtx)
 	unlitMat.SetUnifInt32("material.diffuse", int32(materials.TextureSlot_Diffuse))
@@ -635,6 +646,8 @@ func (g *Game) Init() {
 
 func (g *Game) initFbos() {
 
+	// @TODO: Resize window sized fbos on window resize
+
 	// Demo fbo
 	demoFbo = buffers.NewFramebuffer(uint32(g.WinWidth), uint32(g.WinHeight))
 
@@ -679,6 +692,20 @@ func (g *Game) initFbos() {
 	)
 
 	assert.T(spotLightDepthMapFbo.IsComplete(), "Spot light depth map fbo is not complete after init")
+
+	// Hdr fbo
+	hdrFbo = buffers.NewFramebuffer(uint32(g.WinWidth), uint32(g.WinHeight))
+	hdrFbo.NewColorAttachment(
+		buffers.FramebufferAttachmentType_Texture,
+		buffers.FramebufferAttachmentDataFormat_RGBAF16,
+	)
+
+	hdrFbo.NewDepthStencilAttachment(
+		buffers.FramebufferAttachmentType_Renderbuffer,
+		buffers.FramebufferAttachmentDataFormat_Depth24Stencil8,
+	)
+
+	assert.T(hdrFbo.IsComplete(), "Hdr fbo is not complete after init")
 }
 
 func (g *Game) updateLights() {
@@ -819,6 +846,14 @@ func (g *Game) showDebugWindow() {
 
 	imgui.Spacing()
 
+	imgui.Text("HDR")
+	imgui.Checkbox("Enable HDR", &hdrRendering)
+	if imgui.DragFloat("Exposure", &hdrExposure) {
+		tonemappedScreenQuadMat.SetUnifFloat32("exposure", hdrExposure)
+	}
+
+	imgui.Spacing()
+
 	// Ambient light
 	imgui.Text("Ambient Light")
 
@@ -1075,8 +1110,8 @@ func (g *Game) updateCameraPos() {
 }
 
 var (
-	renderDirLightShadows   = false
-	renderPointLightShadows = false
+	renderDirLightShadows   = true
+	renderPointLightShadows = true
 	renderSpotLightShadows  = true
 
 	rotatingCubeSpeedDeg1 float32 = 45
@@ -1114,17 +1149,19 @@ func (g *Game) Render() {
 
 		if renderDepthBuffer {
 			g.RenderScene(&debugDepthMat)
+		} else if hdrRendering {
+			g.renderHdrFbo()
 		} else {
+
 			g.RenderScene(nil)
+			if renderSkybox {
+				g.DrawSkybox()
+			}
 		}
 	}
 
-	if renderSkybox {
-		g.DrawSkybox()
-	}
-
 	if renderToDemoFbo {
-		g.renderDemoFob()
+		g.renderDemoFbo()
 	}
 }
 
@@ -1222,7 +1259,7 @@ func (g *Game) renderPointLightShadowmaps() {
 	pointLightDepthMapFbo.UnBindWithViewport(uint32(g.WinWidth), uint32(g.WinHeight))
 }
 
-func (g *Game) renderDemoFob() {
+func (g *Game) renderDemoFbo() {
 
 	demoFbo.Bind()
 	demoFbo.Clear()
@@ -1246,6 +1283,23 @@ func (g *Game) renderDemoFob() {
 	window.Rend.DrawVertexArray(&screenQuadMat, &screenQuadVao, 0, 6)
 }
 
+func (g *Game) renderHdrFbo() {
+
+	hdrFbo.Bind()
+	hdrFbo.Clear()
+
+	g.RenderScene(nil)
+
+	if renderSkybox {
+		g.DrawSkybox()
+	}
+
+	hdrFbo.UnBind()
+
+	tonemappedScreenQuadMat.DiffuseTex = hdrFbo.Attachments[0].Id
+	window.Rend.DrawVertexArray(&tonemappedScreenQuadMat, &screenQuadVao, 0, 6)
+}
+
 func (g *Game) RenderScene(overrideMat *materials.Material) {
 
 	tempModelMatrix := cubeModelMat.Clone()

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);
+}