Spotlight shadows

buffers/framebuffer.go

@@ -11,6 +11,7 @@ type FramebufferAttachmentType int32
 const (
 	FramebufferAttachmentType_Unknown FramebufferAttachmentType = iota
 	FramebufferAttachmentType_Texture
+	FramebufferAttachmentType_Texture_Array
 	FramebufferAttachmentType_Renderbuffer
 	FramebufferAttachmentType_Cubemap
 	FramebufferAttachmentType_Cubemap_Array
@@ -21,6 +22,8 @@ func (f FramebufferAttachmentType) IsValid() bool {
 	switch f {
 	case FramebufferAttachmentType_Texture:
 		fallthrough
+	case FramebufferAttachmentType_Texture_Array:
+		fallthrough
 	case FramebufferAttachmentType_Renderbuffer:
 		fallthrough
 	case FramebufferAttachmentType_Cubemap:
@@ -180,6 +183,10 @@ func (fbo *Framebuffer) NewColorAttachment(
 		logging.ErrLog.Fatalf("failed creating color attachment because cubemaps can not be color attachments (at least in this implementation. You might be able to do it manually)\n")
 	}
 
+	if attachType == FramebufferAttachmentType_Texture_Array {
+		logging.ErrLog.Fatalf("failed creating color attachment because texture arrays can not be color attachments (implementation can be updated to support it or you can do it manually)\n")
+	}
+
 	if !attachFormat.IsColorFormat() {
 		logging.ErrLog.Fatalf("failed creating color attachment for framebuffer due to attachment data format not being a valid color type. Data format=%d\n", attachFormat)
 	}
@@ -271,6 +278,10 @@ func (fbo *Framebuffer) NewDepthAttachment(
 		logging.ErrLog.Fatalf("failed creating cubemap array depth attachment because 'NewDepthCubemapArrayAttachment' must be used for that\n")
 	}
 
+	if attachType == FramebufferAttachmentType_Texture_Array {
+		logging.ErrLog.Fatalf("failed creating texture array depth attachment because 'NewDepthTextureArrayAttachment' must be used for that\n")
+	}
+
 	a := FramebufferAttachment{
 		Type:   attachType,
 		Format: attachFormat,
@@ -407,6 +418,68 @@ func (fbo *Framebuffer) NewDepthCubemapArrayAttachment(
 	fbo.Attachments = append(fbo.Attachments, a)
 }
 
+func (fbo *Framebuffer) NewDepthTextureArrayAttachment(
+	attachFormat FramebufferAttachmentDataFormat,
+	numTextures int32,
+) {
+
+	if fbo.HasDepthAttachment() {
+		logging.ErrLog.Fatalf("failed creating texture array depth attachment for framebuffer because a depth attachment already exists\n")
+	}
+
+	if !attachFormat.IsDepthFormat() {
+		logging.ErrLog.Fatalf("failed creating depth attachment for framebuffer due to attachment data format not being a valid depth-stencil type. Data format=%d\n", attachFormat)
+	}
+
+	a := FramebufferAttachment{
+		Type:   FramebufferAttachmentType_Texture_Array,
+		Format: attachFormat,
+	}
+
+	fbo.Bind()
+
+	// Create cubemap array
+	gl.GenTextures(1, &a.Id)
+	if a.Id == 0 {
+		logging.ErrLog.Fatalf("failed to generate texture for framebuffer. GlError=%d\n", gl.GetError())
+	}
+
+	gl.BindTexture(gl.TEXTURE_2D_ARRAY, a.Id)
+
+	gl.TexImage3D(
+		gl.TEXTURE_2D_ARRAY,
+		0,
+		attachFormat.GlInternalFormat(),
+		int32(fbo.Width),
+		int32(fbo.Height),
+		numTextures,
+		0,
+		attachFormat.GlFormat(),
+		gl.FLOAT,
+		nil,
+	)
+
+	gl.TexParameteri(gl.TEXTURE_2D_ARRAY, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
+	gl.TexParameteri(gl.TEXTURE_2D_ARRAY, gl.TEXTURE_MAG_FILTER, gl.NEAREST)
+
+	// This is so that any sampling outside the depth map gives a full depth value.
+	// Useful for example when doing shadow maps where we want things outside
+	// the range of the texture to not show shadow
+	borderColor := []float32{1, 1, 1, 1}
+	gl.TexParameterfv(gl.TEXTURE_2D_ARRAY, gl.TEXTURE_BORDER_COLOR, &borderColor[0])
+	gl.TexParameteri(gl.TEXTURE_2D_ARRAY, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_BORDER)
+	gl.TexParameteri(gl.TEXTURE_2D_ARRAY, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_BORDER)
+
+	gl.BindTexture(gl.TEXTURE_2D_ARRAY, 0)
+
+	// Attach to fbo
+	gl.FramebufferTexture(gl.FRAMEBUFFER, gl.DEPTH_ATTACHMENT, a.Id, 0)
+
+	fbo.UnBind()
+	fbo.ClearFlags |= gl.DEPTH_BUFFER_BIT
+	fbo.Attachments = append(fbo.Attachments, a)
+}
+
 func (fbo *Framebuffer) NewDepthStencilAttachment(
 	attachType FramebufferAttachmentType,
 	attachFormat FramebufferAttachmentDataFormat,

main.go

@@ -32,7 +32,8 @@ import (
 		- Spotlights ✅
 		- Directional light shadows ✅
 		- Point light shadows ✅
-		- Spotlight shadows
+		- Spotlight shadows ✅
+		- UBO support
 		- HDR
 		- Cascaded shadow mapping
 		- Skeletal animations
@@ -70,7 +71,7 @@ func (d *DirLight) GetProjViewMat() gglm.Mat4 {
 	farClip := dirLightFar
 
 	projMat := gglm.Ortho(-size, size, -size, size, nearClip, farClip).Mat4
-	viewMat := gglm.LookAtRH(pos, pos.Clone().Add(d.Dir.Clone().Scale(10)), gglm.NewVec3(0, 1, 0)).Mat4
+	viewMat := gglm.LookAtRH(pos, pos.Clone().Add(&d.Dir), gglm.NewVec3(0, 1, 0)).Mat4
 
 	return *projMat.Mul(&viewMat)
 }
@@ -93,6 +94,9 @@ type PointLight struct {
 
 const (
 	MaxPointLights = 8
+
+	// If this changes update the array depth map shader
+	MaxSpotLights = 4
 )
 
 var (
@@ -121,20 +125,38 @@ type SpotLight struct {
 	Dir            gglm.Vec3
 	DiffuseColor   gglm.Vec3
 	SpecularColor  gglm.Vec3
-	InnerCutoff   float32
+	InnerCutoffRad float32
-	OuterCutoff   float32
+	OuterCutoffRad float32
+
+	// Near plane like 0.x (or anything too small) causes shadows to not work properly.
+	// Needs adjusting as the distance of light to object increases
+	NearPlane float32
+
+	FarPlane float32
 }
 
-// SetCutoffs properly sets the cosine values of the cutoffs using the passed
+func (s *SpotLight) GetProjViewMat() gglm.Mat4 {
-// degrees.
+
-//
+	projMat := gglm.Perspective(s.OuterCutoffRad*2, 1, s.NearPlane, s.FarPlane)
-// The light has full intensity within the inner cutoff, falloff between
+
-// inner-outer cutoff, and zero light beyond the outer cutoff.
+	// Adjust up vector if lightDir is parallel or nearly parallel to upVector
-//
+	// as lookat view matrix breaks if up and look at are parallel
-// The inner cuttoff degree must be *smaller* than the outer cutoff
+	up := gglm.NewVec3(0, 1, 0)
-func (s *SpotLight) SetCutoffs(innerCutoffAngleDeg, outerCutoffAngleDeg float32) {
+	if gglm.Abs32(gglm.DotVec3(&s.Dir, up)) > 0.99 {
-	s.InnerCutoff = gglm.Cos32(innerCutoffAngleDeg * gglm.Deg2Rad)
+		up.SetXY(1, 0)
-	s.OuterCutoff = gglm.Cos32(outerCutoffAngleDeg * gglm.Deg2Rad)
+	}
+
+	viewMat := gglm.LookAtRH(&s.Pos, s.Pos.Clone().Add(&s.Dir), up).Mat4
+
+	return *projMat.Mul(&viewMat)
+}
+
+func (s *SpotLight) InnerCutoffCos() float32 {
+	return gglm.Cos32(s.InnerCutoffRad)
+}
+
+func (s *SpotLight) OuterCutoffCos() float32 {
+	return gglm.Cos32(s.OuterCutoffRad)
 }
 
 const (
@@ -153,20 +175,23 @@ var (
 	cam   *camera.Camera
 
 	// Demo fbo
-	renderToDemoFbo    = true
+	renderToDemoFbo    = false
 	renderToBackBuffer = true
 	demoFboScale       = gglm.NewVec2(0.25, 0.25)
 	demoFboOffset      = gglm.NewVec2(0.75, -0.75)
 	demoFbo            buffers.Framebuffer
 
 	// Dir light fbo
-	showDirLightDepthMapFbo   = true
+	showDirLightDepthMapFbo   = false
 	dirLightDepthMapFboScale  = gglm.NewVec2(0.25, 0.25)
 	dirLightDepthMapFboOffset = gglm.NewVec2(0.75, -0.2)
 	dirLightDepthMapFbo       buffers.Framebuffer
 
 	// Point light fbo
-	omnidirDepthMapFbo buffers.Framebuffer
+	pointLightDepthMapFbo buffers.Framebuffer
+
+	// Spot light fbo
+	spotLightDepthMapFbo buffers.Framebuffer
 
 	screenQuadVao buffers.VertexArray
 	screenQuadMat *materials.Material
@@ -176,7 +201,8 @@ var (
 	containerMat       *materials.Material
 	palleteMat         *materials.Material
 	skyboxMat          *materials.Material
-	dirLightDepthMapMat *materials.Material
+	depthMapMat        *materials.Material
+	arrayDepthMapMat   *materials.Material
 	omnidirDepthMapMat *materials.Material
 	debugDepthMat      *materials.Material
 
@@ -245,13 +271,16 @@ var (
 	}
 	spotLights = [...]SpotLight{
 		{
-			Pos:           *gglm.NewVec3(2, 5, 5),
+			Pos:           *gglm.NewVec3(-4, 7, 5),
-			Dir:           *gglm.NewVec3(0, -1, 0),
+			Dir:           *gglm.NewVec3(1.5, -0.9, 0).Normalize(),
-			DiffuseColor:  *gglm.NewVec3(0, 1, 1),
+			DiffuseColor:  *gglm.NewVec3(1, 0, 1),
 			SpecularColor: *gglm.NewVec3(1, 1, 1),
 			// These must be cosine values
-			InnerCutoff: gglm.Cos32(15 * gglm.Deg2Rad),
+			InnerCutoffRad: 15 * gglm.Deg2Rad,
-			OuterCutoff: gglm.Cos32(20 * gglm.Deg2Rad),
+			OuterCutoffRad: 20 * gglm.Deg2Rad,
+
+			NearPlane: 1,
+			FarPlane:  30,
 		},
 	}
 )
@@ -442,8 +471,9 @@ func (g *Game) Init() {
 	whiteMat.SetUnifVec3("dirLight.dir", &dirLight.Dir)
 	whiteMat.SetUnifVec3("dirLight.diffuseColor", &dirLight.DiffuseColor)
 	whiteMat.SetUnifVec3("dirLight.specularColor", &dirLight.SpecularColor)
-	whiteMat.SetUnifInt32("dirLight.shadowMap", int32(materials.TextureSlot_ShadowMap))
+	whiteMat.SetUnifInt32("dirLight.shadowMap", int32(materials.TextureSlot_ShadowMap1))
 	whiteMat.SetUnifInt32("pointLightCubeShadowMaps", int32(materials.TextureSlot_Cubemap_Array))
+	whiteMat.SetUnifInt32("spotLightShadowMaps", int32(materials.TextureSlot_ShadowMap_Array1))
 
 	containerMat = materials.NewMaterial("Container mat", "./res/shaders/simple.glsl")
 	containerMat.Shininess = 64
@@ -460,8 +490,9 @@ func (g *Game) Init() {
 	containerMat.SetUnifVec3("dirLight.dir", &dirLight.Dir)
 	containerMat.SetUnifVec3("dirLight.diffuseColor", &dirLight.DiffuseColor)
 	containerMat.SetUnifVec3("dirLight.specularColor", &dirLight.SpecularColor)
-	containerMat.SetUnifInt32("dirLight.shadowMap", int32(materials.TextureSlot_ShadowMap))
+	containerMat.SetUnifInt32("dirLight.shadowMap", int32(materials.TextureSlot_ShadowMap1))
 	containerMat.SetUnifInt32("pointLightCubeShadowMaps", int32(materials.TextureSlot_Cubemap_Array))
+	containerMat.SetUnifInt32("spotLightShadowMaps", int32(materials.TextureSlot_ShadowMap_Array1))
 
 	palleteMat = materials.NewMaterial("Pallete mat", "./res/shaders/simple.glsl")
 	palleteMat.Shininess = 64
@@ -477,12 +508,15 @@ func (g *Game) Init() {
 	palleteMat.SetUnifFloat32("material.shininess", palleteMat.Shininess)
 	palleteMat.SetUnifVec3("dirLight.diffuseColor", &dirLight.DiffuseColor)
 	palleteMat.SetUnifVec3("dirLight.specularColor", &dirLight.SpecularColor)
-	palleteMat.SetUnifInt32("dirLight.shadowMap", int32(materials.TextureSlot_ShadowMap))
+	palleteMat.SetUnifInt32("dirLight.shadowMap", int32(materials.TextureSlot_ShadowMap1))
 	palleteMat.SetUnifInt32("pointLightCubeShadowMaps", int32(materials.TextureSlot_Cubemap_Array))
+	palleteMat.SetUnifInt32("spotLightShadowMaps", int32(materials.TextureSlot_ShadowMap_Array1))
 
 	debugDepthMat = materials.NewMaterial("Debug depth mat", "./res/shaders/debug-depth.glsl")
 
-	dirLightDepthMapMat = materials.NewMaterial("Directional Depth Map mat", "./res/shaders/directional-depth-map.glsl")
+	depthMapMat = materials.NewMaterial("Depth Map mat", "./res/shaders/depth-map.glsl")
+
+	arrayDepthMapMat = materials.NewMaterial("Array Depth Map mat", "./res/shaders/array-depth-map.glsl")
 
 	omnidirDepthMapMat = materials.NewMaterial("Omnidirectional Depth Map mat", "./res/shaders/omnidirectional-depth-map.glsl")
 
@@ -540,15 +574,25 @@ func (g *Game) initFbos() {
 
 	assert.T(dirLightDepthMapFbo.IsComplete(), "Depth map fbo is not complete after init")
 
-	// Cubemap fbo
+	// Point light depth map fbo
-	omnidirDepthMapFbo = buffers.NewFramebuffer(1024, 1024)
+	pointLightDepthMapFbo = buffers.NewFramebuffer(1024, 1024)
-	omnidirDepthMapFbo.SetNoColorBuffer()
+	pointLightDepthMapFbo.SetNoColorBuffer()
-	omnidirDepthMapFbo.NewDepthCubemapArrayAttachment(
+	pointLightDepthMapFbo.NewDepthCubemapArrayAttachment(
 		buffers.FramebufferAttachmentDataFormat_DepthF32,
 		MaxPointLights,
 	)
 
-	assert.T(omnidirDepthMapFbo.IsComplete(), "Cubemap fbo is not complete after init")
+	assert.T(pointLightDepthMapFbo.IsComplete(), "Point light depth map fbo is not complete after init")
+
+	// Spot light depth map fbo
+	spotLightDepthMapFbo = buffers.NewFramebuffer(1024, 1024)
+	spotLightDepthMapFbo.SetNoColorBuffer()
+	spotLightDepthMapFbo.NewDepthTextureArrayAttachment(
+		buffers.FramebufferAttachmentDataFormat_DepthF32,
+		MaxSpotLights,
+	)
+
+	assert.T(spotLightDepthMapFbo.IsComplete(), "Spot light depth map fbo is not complete after init")
 }
 
 func (g *Game) updateLights() {
@@ -593,14 +637,17 @@ func (g *Game) updateLights() {
 		palleteMat.SetUnifFloat32(indexString+".farPlane", p.FarPlane)
 	}
 
-	whiteMat.CubemapArrayTex = omnidirDepthMapFbo.Attachments[0].Id
+	whiteMat.CubemapArrayTex = pointLightDepthMapFbo.Attachments[0].Id
-	containerMat.CubemapArrayTex = omnidirDepthMapFbo.Attachments[0].Id
+	containerMat.CubemapArrayTex = pointLightDepthMapFbo.Attachments[0].Id
-	palleteMat.CubemapArrayTex = omnidirDepthMapFbo.Attachments[0].Id
+	palleteMat.CubemapArrayTex = pointLightDepthMapFbo.Attachments[0].Id
 
 	// Spotlights
 	for i := 0; i < len(spotLights); i++ {
 
 		l := &spotLights[i]
+		innerCutoffCos := l.InnerCutoffCos()
+		outerCutoffCos := l.OuterCutoffCos()
+
 		indexString := "spotLights[" + strconv.Itoa(i) + "]"
 
 		whiteMat.SetUnifVec3(indexString+".pos", &l.Pos)
@@ -619,14 +666,18 @@ func (g *Game) updateLights() {
 		containerMat.SetUnifVec3(indexString+".specularColor", &l.SpecularColor)
 		palleteMat.SetUnifVec3(indexString+".specularColor", &l.SpecularColor)
 
-		whiteMat.SetUnifFloat32(indexString+".innerCutoff", l.InnerCutoff)
+		whiteMat.SetUnifFloat32(indexString+".innerCutoff", innerCutoffCos)
-		containerMat.SetUnifFloat32(indexString+".innerCutoff", l.InnerCutoff)
+		containerMat.SetUnifFloat32(indexString+".innerCutoff", innerCutoffCos)
-		palleteMat.SetUnifFloat32(indexString+".innerCutoff", l.InnerCutoff)
+		palleteMat.SetUnifFloat32(indexString+".innerCutoff", innerCutoffCos)
 
-		whiteMat.SetUnifFloat32(indexString+".outerCutoff", l.OuterCutoff)
+		whiteMat.SetUnifFloat32(indexString+".outerCutoff", outerCutoffCos)
-		containerMat.SetUnifFloat32(indexString+".outerCutoff", l.OuterCutoff)
+		containerMat.SetUnifFloat32(indexString+".outerCutoff", outerCutoffCos)
-		palleteMat.SetUnifFloat32(indexString+".outerCutoff", l.OuterCutoff)
+		palleteMat.SetUnifFloat32(indexString+".outerCutoff", outerCutoffCos)
 	}
+
+	whiteMat.ShadowMapTexArray1 = spotLightDepthMapFbo.Attachments[0].Id
+	containerMat.ShadowMapTexArray1 = spotLightDepthMapFbo.Attachments[0].Id
+	palleteMat.ShadowMapTexArray1 = spotLightDepthMapFbo.Attachments[0].Id
 }
 
 func (g *Game) Update() {
@@ -638,11 +689,6 @@ func (g *Game) Update() {
 	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())
-	}
-
 	g.showDebugWindow()
 
 	if input.KeyClicked(sdl.K_F4) {
@@ -763,6 +809,8 @@ func (g *Game) showDebugWindow() {
 	}
 
 	// Spot lights
+	imgui.Checkbox("Render Spot Light Shadows", &renderSpotLightShadows)
+
 	if imgui.BeginListBoxV("Spot Lights", imgui.Vec2{Y: 200}) {
 
 		for i := 0; i < len(spotLights); i++ {
@@ -800,18 +848,27 @@ func (g *Game) showDebugWindow() {
 				palleteMat.SetUnifVec3(indexString+".specularColor", &l.SpecularColor)
 			}
 
-			if imgui.DragFloat("Inner Cutoff", &l.InnerCutoff) {
+			if imgui.DragFloat("Inner Cutoff Radians", &l.InnerCutoffRad) {
-				whiteMat.SetUnifFloat32(indexString+".innerCutoff", l.InnerCutoff)
+
-				containerMat.SetUnifFloat32(indexString+".innerCutoff", l.InnerCutoff)
+				cos := l.InnerCutoffCos()
-				palleteMat.SetUnifFloat32(indexString+".innerCutoff", l.InnerCutoff)
+
+				whiteMat.SetUnifFloat32(indexString+".innerCutoff", cos)
+				containerMat.SetUnifFloat32(indexString+".innerCutoff", cos)
+				palleteMat.SetUnifFloat32(indexString+".innerCutoff", cos)
 			}
 
-			if imgui.DragFloat("Outer Cutoff", &l.OuterCutoff) {
+			if imgui.DragFloat("Outer Cutoff Radians", &l.OuterCutoffRad) {
-				whiteMat.SetUnifFloat32(indexString+".outerCutoff", l.OuterCutoff)
+
-				containerMat.SetUnifFloat32(indexString+".outerCutoff", l.OuterCutoff)
+				cos := l.OuterCutoffCos()
-				palleteMat.SetUnifFloat32(indexString+".outerCutoff", l.OuterCutoff)
+
+				whiteMat.SetUnifFloat32(indexString+".outerCutoff", cos)
+				containerMat.SetUnifFloat32(indexString+".outerCutoff", cos)
+				palleteMat.SetUnifFloat32(indexString+".outerCutoff", cos)
 			}
 
+			imgui.DragFloat("Spot Near Plane", &l.NearPlane)
+			imgui.DragFloat("Spot Far Plane", &l.FarPlane)
+
 			imgui.TreePop()
 		}
 
@@ -902,24 +959,36 @@ func (g *Game) updateCameraPos() {
 var (
 	renderDirLightShadows   = true
 	renderPointLightShadows = true
+	renderSpotLightShadows  = true
 
 	rotatingCubeSpeedDeg1 float32 = 45
 	rotatingCubeSpeedDeg2 float32 = 120
+	rotatingCubeSpeedDeg3 float32 = 120
 	rotatingCubeTrMat1            = *gglm.NewTrMatId().Translate(gglm.NewVec3(-4, -1, 4))
 	rotatingCubeTrMat2            = *gglm.NewTrMatId().Translate(gglm.NewVec3(-1, 0.5, 4))
+	rotatingCubeTrMat3            = *gglm.NewTrMatId().Translate(gglm.NewVec3(5, 0.5, 4))
 )
 
 func (g *Game) Render() {
 
+	whiteMat.SetUnifVec3("camPos", &cam.Pos)
+	containerMat.SetUnifVec3("camPos", &cam.Pos)
+	palleteMat.SetUnifVec3("camPos", &cam.Pos)
+
 	rotatingCubeTrMat1.Rotate(rotatingCubeSpeedDeg1*gglm.Deg2Rad*timing.DT(), gglm.NewVec3(0, 1, 0))
 	rotatingCubeTrMat2.Rotate(rotatingCubeSpeedDeg2*gglm.Deg2Rad*timing.DT(), gglm.NewVec3(1, 1, 0))
+	rotatingCubeTrMat3.Rotate(rotatingCubeSpeedDeg3*gglm.Deg2Rad*timing.DT(), gglm.NewVec3(1, 1, 1))
 
 	if renderDirLightShadows {
-		g.renderDirectionalShadowmap()
+		g.renderDirectionalLightShadowmap()
+	}
+
+	if renderSpotLightShadows {
+		g.renderSpotLightShadowmaps()
 	}
 
 	if renderPointLightShadows {
-		g.renderOmnidirectionalShadowmap()
+		g.renderPointLightShadowmaps()
 	}
 
 	if renderToBackBuffer {
@@ -940,21 +1009,16 @@ func (g *Game) Render() {
 	}
 }
 
-func (g *Game) renderDirectionalShadowmap() {
+func (g *Game) renderDirectionalLightShadowmap() {
 
 	// Set some uniforms
 	dirLightProjViewMat := dirLight.GetProjViewMat()
 
-	whiteMat.SetUnifVec3("camPos", &cam.Pos)
 	whiteMat.SetUnifMat4("dirLightProjViewMat", &dirLightProjViewMat)
-
-	containerMat.SetUnifVec3("camPos", &cam.Pos)
 	containerMat.SetUnifMat4("dirLightProjViewMat", &dirLightProjViewMat)
-
-	palleteMat.SetUnifVec3("camPos", &cam.Pos)
 	palleteMat.SetUnifMat4("dirLightProjViewMat", &dirLightProjViewMat)
 
-	dirLightDepthMapMat.SetUnifMat4("projViewMat", &dirLightProjViewMat)
+	depthMapMat.SetUnifMat4("projViewMat", &dirLightProjViewMat)
 
 	// Start rendering
 	dirLightDepthMapFbo.BindWithViewport()
@@ -966,7 +1030,7 @@ func (g *Game) renderDirectionalShadowmap() {
 	//
 	// Some note that this is too troublesome and fails in many cases. Might be better to remove.
 	gl.CullFace(gl.FRONT)
-	g.RenderScene(dirLightDepthMapMat)
+	g.RenderScene(depthMapMat)
 	gl.CullFace(gl.BACK)
 
 	dirLightDepthMapFbo.UnBindWithViewport(uint32(g.WinWidth), uint32(g.WinHeight))
@@ -980,10 +1044,41 @@ func (g *Game) renderDirectionalShadowmap() {
 	}
 }
 
-func (g *Game) renderOmnidirectionalShadowmap() {
+func (g *Game) renderSpotLightShadowmaps() {
 
-	omnidirDepthMapFbo.BindWithViewport()
+	for i := 0; i < len(spotLights); i++ {
-	omnidirDepthMapFbo.Clear()
+
+		l := &spotLights[i]
+		indexStr := strconv.Itoa(i)
+		projViewMatIndexStr := "spotLightProjViewMats[" + indexStr + "]"
+
+		// Set render uniforms
+		projViewMat := l.GetProjViewMat()
+
+		whiteMat.SetUnifMat4(projViewMatIndexStr, &projViewMat)
+		containerMat.SetUnifMat4(projViewMatIndexStr, &projViewMat)
+		palleteMat.SetUnifMat4(projViewMatIndexStr, &projViewMat)
+
+		// Set depth uniforms
+		arrayDepthMapMat.SetUnifMat4("projViewMats["+indexStr+"]", &projViewMat)
+	}
+
+	// Render
+	spotLightDepthMapFbo.BindWithViewport()
+	spotLightDepthMapFbo.Clear()
+
+	// Front culling created issues
+	// gl.CullFace(gl.FRONT)
+	g.RenderScene(arrayDepthMapMat)
+	// gl.CullFace(gl.BACK)
+
+	spotLightDepthMapFbo.UnBindWithViewport(uint32(g.WinWidth), uint32(g.WinHeight))
+}
+
+func (g *Game) renderPointLightShadowmaps() {
+
+	pointLightDepthMapFbo.BindWithViewport()
+	pointLightDepthMapFbo.Clear()
 
 	for i := 0; i < len(pointLights); i++ {
 
@@ -995,7 +1090,7 @@ func (g *Game) renderOmnidirectionalShadowmap() {
 		omnidirDepthMapMat.SetUnifFloat32("farPlane", p.FarPlane)
 
 		// Set projView matrices
-		projViewMats := p.GetProjViewMats(float32(omnidirDepthMapFbo.Width), float32(omnidirDepthMapFbo.Height))
+		projViewMats := p.GetProjViewMats(float32(pointLightDepthMapFbo.Width), float32(pointLightDepthMapFbo.Height))
 		for j := 0; j < len(projViewMats); j++ {
 			omnidirDepthMapMat.SetUnifMat4("cubemapProjViewMats["+strconv.Itoa(j)+"]", &projViewMats[j])
 		}
@@ -1003,7 +1098,7 @@ func (g *Game) renderOmnidirectionalShadowmap() {
 		g.RenderScene(omnidirDepthMapMat)
 	}
 
-	omnidirDepthMapFbo.UnBindWithViewport(uint32(g.WinWidth), uint32(g.WinHeight))
+	pointLightDepthMapFbo.UnBindWithViewport(uint32(g.WinWidth), uint32(g.WinHeight))
 }
 
 func (g *Game) renderDemoFob() {
@@ -1070,8 +1165,8 @@ func (g *Game) RenderScene(overrideMat *materials.Material) {
 
 	// Rotating cubes
 	window.Rend.DrawMesh(cubeMesh, &rotatingCubeTrMat1, cubeMat)
-
 	window.Rend.DrawMesh(cubeMesh, &rotatingCubeTrMat2, cubeMat)
+	window.Rend.DrawMesh(cubeMesh, &rotatingCubeTrMat3, cubeMat)
 
 	// Cubes generator
 	// rowSize := 1

materials/material.go

@@ -16,8 +16,9 @@ const (
 	TextureSlot_Normal           TextureSlot = 2
 	TextureSlot_Emission         TextureSlot = 3
 	TextureSlot_Cubemap          TextureSlot = 10
-	TextureSlot_ShadowMap     TextureSlot = 11
+	TextureSlot_Cubemap_Array    TextureSlot = 11
-	TextureSlot_Cubemap_Array TextureSlot = 12
+	TextureSlot_ShadowMap1       TextureSlot = 12
+	TextureSlot_ShadowMap_Array1 TextureSlot = 13
 )
 
 type Material struct {
@@ -43,6 +44,7 @@ type Material struct {
 
 	// Shadowmaps
 	ShadowMapTex1      uint32
+	ShadowMapTexArray1 uint32
 }
 
 func (m *Material) Bind() {
@@ -80,9 +82,14 @@ func (m *Material) Bind() {
 	}
 
 	if m.ShadowMapTex1 != 0 {
-		gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_ShadowMap))
+		gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_ShadowMap1))
 		gl.BindTexture(gl.TEXTURE_2D, m.ShadowMapTex1)
 	}
+
+	if m.ShadowMapTexArray1 != 0 {
+		gl.ActiveTexture(uint32(gl.TEXTURE0 + TextureSlot_ShadowMap_Array1))
+		gl.BindTexture(gl.TEXTURE_2D_ARRAY, m.ShadowMapTexArray1)
+	}
 }
 
 func (m *Material) UnBind() {

res/shaders/array-depth-map.glsl

@@ -0,0 +1,54 @@
+//shader:vertex
+#version 410
+
+layout(location=0) in vec3 vertPosIn;
+
+uniform mat4 modelMat;
+
+void main()
+{
+    gl_Position = modelMat * vec4(vertPosIn, 1);
+}
+
+//shader:geometry
+#version 410
+
+layout (triangles) in;
+
+#define NUM_PROJ_VIEW_MATS 4
+
+// 3 * NUM_PROJ_VIEW_MATS
+layout (triangle_strip, max_vertices=12) out;
+
+// This is the same number as max spot lights or whatever else is being rendered
+uniform mat4 projViewMats[NUM_PROJ_VIEW_MATS];
+
+out vec4 FragPos;
+
+void main()
+{
+    for(int projViewMatIndex = 0; projViewMatIndex < NUM_PROJ_VIEW_MATS; projViewMatIndex++){
+
+        gl_Layer = projViewMatIndex;
+        mat4 projViewMat = projViewMats[projViewMatIndex];
+
+        for(int i = 0; i < 3; i++)
+        {
+            FragPos = gl_in[i].gl_Position;
+            gl_Position = projViewMat * FragPos;
+            EmitVertex();
+        }
+        EndPrimitive();
+    }
+}
+
+//shader:fragment
+#version 410
+
+in vec4 FragPos;
+
+void main()
+{
+    // This implicitly writes to the depth buffer with no color operations
+    // Equivalent: gl_FragDepth = gl_FragCoord.z;
+}

res/shaders/simple.glsl

@@ -6,15 +6,19 @@ layout(location=1) in vec3 vertNormalIn;
 layout(location=2) in vec2 vertUV0In;
 layout(location=3) in vec3 vertColorIn;
 
+uniform mat4 modelMat;
+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];
-uniform mat4 modelMat;
-uniform mat4 projViewMat;
-uniform mat4 dirLightProjViewMat;
 
 void main()
 {
@@ -31,6 +35,9 @@ void main()
     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;
 }
 
@@ -81,6 +88,7 @@ struct SpotLight {
 
 #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);
@@ -90,6 +98,7 @@ in vec3 vertNormal;
 in vec2 vertUV0;
 in vec3 fragPos;
 in vec4 fragPosDirLight;
+in vec4 fragPosSpotLight[NUM_SPOT_LIGHTS];
 
 out vec4 fragColor;
 
@@ -123,9 +132,9 @@ float CalcDirShadow(sampler2D shadowMap, vec3 lightDir)
     // Basically get soft shadows by averaging this texel and surrounding ones
     float shadow = 0;
     vec2 texelSize = 1 / textureSize(shadowMap, 0);
-    for(int x = -1; x <= 1; ++x)
+    for(int x = -1; x <= 1; x++)
     {
-        for(int y = -1; y <= 1; ++y)
+        for(int y = -1; y <= 1; y++)
         {
             float pcfDepth = texture(shadowMap, projCoords.xy + vec2(x, y) * texelSize).r; 
 
@@ -205,7 +214,47 @@ vec3 CalcPointLight(PointLight pointLight, int lightIndex)
     return (finalDiffuse + finalSpecular) * attenuation * (1 - shadow);
 }
 
-vec3 CalcSpotLight(SpotLight light)
+float CalcSpotShadow(vec3 lightDir, int lightIndex)
+{
+    // Move from clip space to NDC
+    vec3 projCoords = fragPosSpotLight[lightIndex].xyz / fragPosSpotLight[lightIndex].w;
+
+    // Move from [-1,1] to [0, 1]
+    projCoords = projCoords * 0.5 + 0.5;
+
+    // If sampling outside the depth texture then force 'no shadow'
+    if(projCoords.z > 1)
+        return 0;
+
+    // currentDepth is the fragment depth from the light's perspective
+    float currentDepth = projCoords.z;
+
+    // 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);
+
+    // 'Percentage Close Filtering'.
+    // Basically get soft shadows by averaging this texel and surrounding ones
+    float shadow = 0;
+    vec2 texelSize = 1 / textureSize(spotLightShadowMaps, 0).xy;
+    for(int x = -1; x <= 1; x++)
+    {
+        for(int y = -1; y <= 1; y++)
+        {
+            float pcfDepth = texture(spotLightShadowMaps, vec3(projCoords.xy + vec2(x, y) * texelSize, lightIndex)).r; 
+
+            // If our depth is larger than the lights closest depth at the texel we checked (projCoords),
+            // then there is something closer to the light than us, and so we are in shadow
+            shadow += currentDepth - bias > pcfDepth ? 1 : 0;
+        }
+    }
+
+    shadow /= 9;
+
+    return shadow;
+}
+
+vec3 CalcSpotLight(SpotLight light, int lightIndex)
 {
     if (light.innerCutoff == 0)
         return vec3(0);
@@ -231,7 +280,10 @@ vec3 CalcSpotLight(SpotLight light)
     float specularAmount = pow(max(dot(normalizedVertNorm, halfwayDir), 0.0), material.shininess);
     vec3 finalSpecular = specularAmount * light.specularColor * specularTexColor.rgb;
 
-    return (finalDiffuse + finalSpecular) * intensity;
+    // Shadow
+    float shadow = CalcSpotShadow(fragToLightDir, lightIndex);
+
+    return (finalDiffuse + finalSpecular) * intensity * (1 - shadow);
 }
 
 void main()
@@ -254,7 +306,7 @@ void main()
 
     for (int i = 0; i < NUM_SPOT_LIGHTS; i++)
     {
-        finalColor += CalcSpotLight(spotLights[i]);
+        finalColor += CalcSpotLight(spotLights[i], i);
     }
 
     vec3 finalEmission = emissionTexColor.rgb;