Enabled cascaded shadow maps in forward rendering mode

data/shaders/fs_default.glsl

@@ -7,12 +7,33 @@ uniform sampler2D uAlbedoTexture;
 
 #define USE_SAMPLER2D_SHADOW 1
 
+//
+// Single Shadow MAp
+//
+
 #ifdef USE_SAMPLER2D_SHADOW
 uniform sampler2DShadow uShadowMap;
 #else
 uniform sampler2D uShadowMap;
 #endif
 
+//
+// Cascaded Shadow Maps
+//
+
+const int NUM_SPLITS = 4;
+
+#ifdef USE_SAMPLER2D_SHADOW
+uniform sampler2DShadow uShadowMaps[NUM_SPLITS];
+#else
+uniform sampler2D uShadowMaps[NUM_SPLITS];
+#endif
+
+uniform mat4 uViewToLightMatrix[NUM_SPLITS];
+uniform float uShowCascadesAlpha;
+uniform vec4 uShadowSplits;
+uniform vec4 uShadowSplitBias;
+
 uniform mat4 uModelMatrix;
 uniform mat4 uViewMatrix;
 
@@ -26,7 +47,7 @@ out vec4 outColor;
 out vec3 outPosition;
 out vec3 outNormal;
 
-float ShadowCalculationPCF(vec4 frag_pos_light_space) {
+float ShadowCalculationPCF_OLD(vec4 frag_pos_light_space) {
 	vec3 projected_coordinates = frag_pos_light_space.xyz / frag_pos_light_space.w;
 	projected_coordinates = projected_coordinates * 0.5 + 0.5;
 
@@ -54,46 +75,101 @@ float ShadowCalculationPCF(vec4 frag_pos_light_space) {
 	return shadow;
 }
 
-float ShadowCalculation(vec4 frag_pos_light_space) {
+#ifdef USE_SAMPLER2D_SHADOW
+float ShadowCalculationPCF(sampler2DShadow shadow_map, vec4 frag_pos_light_space, vec3 frag_normal_light_space, float shadow_bias) {
+#else
+float ShadowCalculationPCF(sampler2D shadow_map, vec4 frag_pos_light_space, vec3 frag_normal_light_space, float shadow_bias) {
+#endif
 	vec3 projected_coordinates = frag_pos_light_space.xyz / frag_pos_light_space.w;
 	projected_coordinates = projected_coordinates * 0.5 + 0.5;
 
+	if (abs(projected_coordinates.z) > 1.0 ) {
+		return 0.0;
+	}
+
 	float current_depth = projected_coordinates.z;
 
-	float bias = 0.01;
+	float bias = 0.00;
+	bias = max(shadow_bias * (1.0 - dot(frag_normal_light_space, uLightDirection)), shadow_bias);
 
+	float shadow = 0.0;
+	vec2 texel_size = 1.0 / textureSize(shadow_map, 0);
+	for (int x = -1; x <= 1; ++x) {
+		for (int y = -1; y <= 1; ++y) {
 #ifdef USE_SAMPLER2D_SHADOW
-	float closest_depth = texture(uShadowMap, vec3(projected_coordinates.xy, current_depth - bias));
+			vec2 coordinate = projected_coordinates.xy + vec2(x, y) * texel_size;
+			float pcf_depth = texture(shadow_map, vec3(coordinate, current_depth - bias));
 #else
-	float closest_depth = texture(uShadowMap, projected_coordinates.xy).r;
+			float pcf_depth = texture(shadow_map, projected_coordinates.xy).r;
-	bias = max(0.005 * (1.0 - dot(ioFragNormal, uLightDirection)), 0.003);
 #endif
+			shadow += current_depth - bias > pcf_depth ? 1.0 : 0.0;
+		}
+	}
 
-	return current_depth - bias > closest_depth ? 1.0 : 0.0;
+	shadow /= 9.0;
+
+	return shadow;
+}
+
+vec3 get_cascade_color (float depth) {
+	if (depth < uShadowSplits[0]) {
+		return vec3 (1.0, 0.0, 0.0);
+	} else if (depth < uShadowSplits[1]) {
+		return vec3 (1.0, 1.0, 0.0);
+	} else if (depth < uShadowSplits[2]) {
+		return vec3 (0.0, 1.0, 0.0);
+	}
+
+	return vec3 (0.0, 0.0, 1.0);
 }
 
 void main() {
 	vec4 albedo_color = texture(uAlbedoTexture, ioFragTexCoords) * ioFragColor * uColor;
+	vec3 position = ioFragPosition.xyz;
 
 	// ambient lighting
 	float ambient_strength = 0.2;
 	vec4 ambient = ambient_strength * albedo_color;
 
 	// diffuse lighting
-	vec3 normal_dir = normalize(ioFragNormal);
+	vec3 normal = normalize(ioFragNormal);
 	vec3 light_dir = -(mat3(uViewMatrix)) * uLightDirection;
-	float diff = max(dot(normal_dir, light_dir), 0.0);
+	float diff = max(dot(normal, light_dir), 0.0);
 	vec4 diffuse = diff * albedo_color;
 
 	// specular lighting
 	vec3 view_dir = normalize(-ioFragPosition);
 	vec3 halfway_dir = normalize(light_dir + view_dir);
 
-	float spec = pow(max(dot(normal_dir, halfway_dir), 0.0), 32);
+	float spec = pow(max(dot(normal, halfway_dir), 0.0), 32);
 	vec4 specular = spec * vec4(0.5);
 
 	// shadow
-	float shadow = ShadowCalculationPCF(ioFragPosLightSpace);
+	float shadow = 0;
+	if (-position.z < uShadowSplits[0]) {
+		// shadow (need to transform position and normal to light space)
+		vec4 position_light_space = uViewToLightMatrix[0] * vec4(position, 1.0);
+		vec3 normal_light_space = (transpose(inverse(uViewToLightMatrix[0])) * vec4(normal, 1.0)).xyz;
+		shadow = ShadowCalculationPCF(uShadowMaps[0], position_light_space, normal, uShadowSplitBias[0]);
+	} else if (-position.z< uShadowSplits[1]) {
+		vec4 position_light_space = uViewToLightMatrix[1] * vec4(position, 1.0);
+		vec3 normal_light_space = (transpose(inverse(uViewToLightMatrix[1])) * vec4(normal, 1.0)).xyz;
+		shadow = ShadowCalculationPCF(uShadowMaps[1], position_light_space, normal, uShadowSplitBias[1]);
+	} else if (-position.z< uShadowSplits[2]) {
+		vec4 position_light_space = uViewToLightMatrix[2] * vec4(position, 1.0);
+		vec3 normal_light_space = (transpose(inverse(uViewToLightMatrix[2])) * vec4(normal, 1.0)).xyz;
+		shadow = ShadowCalculationPCF(uShadowMaps[2], position_light_space, normal, uShadowSplitBias[2]);
+	} else {
+		vec4 position_light_space = uViewToLightMatrix[3] * vec4(position, 1.0);
+		vec3 normal_light_space = (transpose(inverse(uViewToLightMatrix[3])) * vec4(normal, 1.0)).xyz;
+		shadow = ShadowCalculationPCF(uShadowMaps[3], position_light_space, normal, uShadowSplitBias[3]);
+	}
+
+	vec4 cascade = vec4(get_cascade_color(-position.z), 1.0);
+	ambient = (uShowCascadesAlpha * cascade) + (1.0 - uShowCascadesAlpha) * ambient;
+  outColor = (ambient + (1.0 - shadow) * (diffuse + specular));
+
+//	float shadow = ShadowCalculationPCF(uShadowMap, ioFragPosLightSpace, normal, 0.001);
 	outColor = ambient + (1.0 - shadow) * (diffuse + specular);
 
 	outPosition = ioFragPosition.xyz;

data/shaders/vs_default.glsl

@@ -22,7 +22,7 @@ out vec4 ioFragPosLightSpace;
 void main() {
 	mat4 model_view_matrix = uViewMatrix * uModelMatrix;
 
-	ioFragPosition = (model_view_matrix* inCoord).xyz;
+	ioFragPosition = (model_view_matrix * inCoord).xyz;
 	ioFragNormal = transpose(inverse(mat3(model_view_matrix))) * inNormal;
 	ioFragTexCoords = inUV;
 	ioFragColor = inColor;

data/shaders/vs_deferred_geometry.glsl

@@ -8,11 +8,13 @@ in vec4 inColor;
 uniform mat4 uModelMatrix;
 uniform mat4 uViewMatrix;
 uniform mat4 uProjectionMatrix;
+uniform mat4 uLightSpaceMatrix;
 
 out vec3 ioFragPosition;
 out vec3 ioFragNormal;
 out vec2 ioFragTexCoords;
 out vec4 ioFragColor;
+out vec4 ioFragPosLightSpace;
 
 void main() {
 	mat4 model_view_matrix = uViewMatrix * uModelMatrix;
@@ -21,6 +23,7 @@ void main() {
 	ioFragNormal = transpose(inverse(mat3(model_view_matrix))) * inNormal;
 	ioFragTexCoords = inUV;
 	ioFragColor = inColor;
+	ioFragPosLightSpace = uLightSpaceMatrix * uModelMatrix * inCoord;
 
 	gl_Position = uProjectionMatrix * model_view_matrix * inCoord;
 }

src/modules/RenderModule.cc

@@ -124,7 +124,6 @@ static void module_serialize (
 	SerializeBool(*serializer, "protot.RenderModule.mLight.mDebugDrawSplitLightBounds", gRenderer->mLight.mDebugDrawSplitLightBounds);
 	SerializeVec4 (*serializer, "protot.RenderModule.mLight.mSplitBias", gRenderer->mLight.mSplitBias);
 	SerializeVec4 (*serializer, "protot.RenderModule.mLight.mShadowSplits", gRenderer->mLight.mShadowSplits);
-
 }
 
 static void module_finalize(struct module_state *state) {
@@ -584,12 +583,6 @@ void Renderer::CheckRenderBuffers() {
 	}
 }
 
-void Renderer::ResizeTargets(int width, int height) {
-    mSSAOTarget.Resize(mSceneAreaWidth, mSceneAreaHeight, RenderTarget::EnableColor);
-    mSSAOBlurTarget.Resize(mSceneAreaWidth, mSceneAreaHeight, RenderTarget::EnableColor);
-
-}
-
 void Renderer::RenderGl() {
 	CheckRenderBuffers();
 
@@ -652,12 +645,21 @@ void Renderer::RenderGl() {
 		* mCamera.mViewMatrix
 		* mCamera.mProjectionMatrix;
 
+  // Clear the SSAO Blur target
+  if (!mIsSSAOEnabled) {
+    mSSAOBlurTarget.Bind();
+    GLenum draw_attachment_0[] = {GL_COLOR_ATTACHMENT0 };
+    glDrawBuffers(1, draw_attachment_0);
+    glClearColor(1.f, 1.f, 1.f, 1.f);
+    glClear(GL_COLOR_BUFFER_BIT);
+    glDisable(GL_DEPTH_TEST);
+ }
+
   // enable the render target
 	mForwardRenderingTarget.Bind();
-
+  GLenum draw_attachment_0[] = {GL_COLOR_ATTACHMENT0 };
-	if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
+  glDrawBuffers(1, draw_attachment_0);
-		gLog ("Cannot render: frame buffer invalid!");
+  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-	}
 
 	glEnable(GL_DEPTH_TEST);
 	RenderProgram *program = &mDefaultProgram;
@@ -711,29 +713,54 @@ void Renderer::RenderGl() {
 	gVertexArray.Bind();
 	gXZPlaneGrid.Draw(GL_LINES);
 
-	if (!mIsSSAOEnabled) {
-		// Clear the SSAO Blur target
-		mSSAOBlurTarget.Bind();
-		glViewport(0, 0, mCamera.mWidth, mCamera.mHeight);
-		GLenum draw_attachment_0[] = {GL_COLOR_ATTACHMENT0 };
-		glDrawBuffers(1, draw_attachment_0);
-		glClearColor(255, 255, 255, 255);
-		glClear(GL_COLOR_BUFFER_BIT);
-		glDisable(GL_DEPTH_TEST);
-		gVertexArray.Bind();
-		gScreenQuad.Draw(GL_TRIANGLES);
-	}
-
 	// Scene
 	glUseProgram(program->mProgramId);
 
+	glActiveTexture(GL_TEXTURE0);
+	glBindTexture(GL_TEXTURE_2D, mLight.mShadowMapTarget.mDepthTexture);
+	program->SetInt("uShadowMap",  0);
+
+	if (!mUseDeferred) {
+		// Shadow Map Cascades
+		glActiveTexture(GL_TEXTURE5);
+		glBindTexture(GL_TEXTURE_2D, mLight.mSplitTarget[0].mDepthTexture);
+		glActiveTexture(GL_TEXTURE6);
+		glBindTexture(GL_TEXTURE_2D, mLight.mSplitTarget[1].mDepthTexture);
+		glActiveTexture(GL_TEXTURE7);
+		glBindTexture(GL_TEXTURE_2D, mLight.mSplitTarget[2].mDepthTexture);
+		glActiveTexture(GL_TEXTURE8);
+		glBindTexture(GL_TEXTURE_2D, mLight.mSplitTarget[3].mDepthTexture);
+
+		GLint shadow_maps[cNumSplits];
+		shadow_maps[0] = 5;
+		shadow_maps[1] = 6;
+		shadow_maps[2] = 7;
+		shadow_maps[3] = 8;
+		program->SetIntArray("uShadowMaps", cNumSplits, shadow_maps);
+
+		Matrix44f light_matrices[cNumSplits];
+
+		for (int i = 0; i < cNumSplits; ++i) {
+			light_matrices[i] = mCamera.mViewMatrix.inverse() 
+				* mLight.mSplitLightFrustum[i];
+		}
+		program->SetFloat("uNear", mCamera.mNear);
+		program->SetFloat("uFar", mCamera.mFar);
+		program->SetVec4("uShadowSplits", mLight.mShadowSplits);
+		program->SetVec4("uShadowSplitBias", mLight.mSplitBias);
+		program->SetFloat("uShowCascadesAlpha", mLight.mShowCascadesAlpha);
+
+    program->SetMat44Array("uViewToLightMatrix", cNumSplits, light_matrices);
+		program->SetMat44("uLightSpaceMatrix", mLight.mLightSpaceMatrix); 
+	}
+
 	RenderScene(*program, mCamera);
 
 	if (mSettings->RenderMode == SceneRenderModeDepth) {
 		mForwardRenderingTarget.RenderToLinearizedDepth(mCamera.mNear, mCamera.mFar, mCamera.mIsOrthographic);
 	}
 
-	if (mUseDeferred && mIsSSAOEnabled) {
+	if (mIsSSAOEnabled) {
 		mSSAOTarget.Bind();
 		glViewport(0, 0, mCamera.mWidth, mCamera.mHeight);
 		GLenum draw_attachment_0[] = {GL_COLOR_ATTACHMENT0 };
@@ -774,6 +801,7 @@ void Renderer::RenderGl() {
 		mSSAOBlurTarget.Bind();
 		glViewport(0, 0, mCamera.mWidth, mCamera.mHeight);
 		glDrawBuffers(1, draw_attachment_0);
+		glClearColor(1.f, 1.f, 1.f, 1.f);
 		glClear(GL_COLOR_BUFFER_BIT);
 		glDisable(GL_DEPTH_TEST);
 		
@@ -830,14 +858,14 @@ void Renderer::RenderGl() {
 		glActiveTexture(GL_TEXTURE8);
 		glBindTexture(GL_TEXTURE_2D, mLight.mSplitTarget[3].mDepthTexture);
 
-		GLint shadow_maps[4];
+		GLint shadow_maps[cNumSplits];
 		shadow_maps[0] = 5;
 		shadow_maps[1] = 6;
 		shadow_maps[2] = 7;
 		shadow_maps[3] = 8;
 		mDeferredLighting.SetIntArray("uShadowMap", cNumSplits, shadow_maps);
 
-		Matrix44f light_matrices[3];
+		Matrix44f light_matrices[cNumSplits];
 
 		for (int i = 0; i < cNumSplits; ++i) {
 			light_matrices[i] = mCamera.mViewMatrix.inverse() 
@@ -860,6 +888,7 @@ void Renderer::RenderGl() {
 		mDeferredLighting.SetVec3("uLightDirection", light_direction.normalized());
 		mDeferredLighting.SetFloat("uShadowBias", mLight.mShadowBias);
 
+		glDisable(GL_DEPTH_TEST);
 		gVertexArray.Bind();
 		gScreenQuad.Draw(GL_TRIANGLES);
 	}
@@ -945,12 +974,6 @@ void Renderer::SubmitRenderCommands (RenderProgram &program, const Camera &camer
 	program.SetVec3("uLightDirection", mLight.mDirection);
 	program.SetVec3("uViewPosition", camera.mEye);
 	
-	program.SetMat44("uLightSpaceMatrix", mLight.mLightSpaceMatrix); 
-
-	glActiveTexture(GL_TEXTURE0);
-	glBindTexture(GL_TEXTURE_2D, mLight.mShadowMapTarget.mDepthTexture);
-	program.SetInt("uShadowMap",  0);
-
 	glActiveTexture(GL_TEXTURE1);
 	glBindTexture(GL_TEXTURE_2D, mDefaultTexture.mTextureId);
 	program.SetInt("uAlbedoTexture",  1);