使用subroutine

main.cpp

@@ -91,9 +91,9 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 	glewInit();
 
 	/*创建program*/
-	GLuint program = CreateGPUProgram("res/shader/diffuse.vs", "res/shader/diffuse.fs");
+	GLuint program = CreateGPUProgram("res/shader/MixLight.vs", "res/shader/MixLight.fs");
 
-	GLuint posLocation, texcoordLocation, normalLocation, MLocation, VLocation, PLocation, NMLocation, textureLocation, offsetLocation;
+	GLuint posLocation, texcoordLocation, normalLocation, MLocation, VLocation, PLocation, NMLocation, textureLocation, offsetLocation, surfaceColorLocation;
 	posLocation = glGetAttribLocation(program, "pos");
 	texcoordLocation = glGetAttribLocation(program, "texcoord");
 	normalLocation = glGetAttribLocation(program, "normal");
@@ -104,6 +104,11 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 	NMLocation = glGetUniformLocation(program, "NM");
 	textureLocation = glGetUniformLocation(program, "U_MainTexture");
 	
+	/*使用subroutine*/
+	surfaceColorLocation = glGetSubroutineUniformLocation(program, GL_FRAGMENT_SHADER, "U_SurfaceColor");
+	GLuint ambientLightIndex = glGetSubroutineIndex(program, GL_FRAGMENT_SHADER, "Ambient");
+	GLuint diffuseLightIndex = glGetSubroutineIndex(program, GL_FRAGMENT_SHADER, "Diffuse");
+	GLuint specularLightIndex = glGetSubroutineIndex(program, GL_FRAGMENT_SHADER, "Specular");
 
 	/*load model*/
 	unsigned int *indexes = nullptr;
@@ -126,16 +131,6 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 	/*创建纹理*/
 	GLuint mainTexture = CreateTextureFromFile("res/image/niutou.bmp");
 
-	/* 定义了3个点表示3个模型的位置 */
-	float posOffsets[] = {
-		-1.0f, 0.0f, 0.0f,
-		0.0f, 0.0f, 0.0f,
-		1.0f, 0.0f, 0.0f
-	};
-	/*创建offset VBO*/
-	GLuint offsetVBO = CreateBufferObject(GL_ARRAY_BUFFER, sizeof(float)*9, GL_STATIC_DRAW, posOffsets);
-
-
 	glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
 	glEnable(GL_DEPTH_TEST);
 
@@ -149,7 +144,7 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 		0,0,0,1
 	};
 
-	glm::mat4 model = glm::translate(0.0f, -0.5f, -4.0f) * glm::rotate(-90.0f, 0.0f, 1.0f, 0.0f)*glm::scale(0.01f,0.01f,0.01f);
+	glm::mat4 model = glm::translate(0.0f, -0.5f, -3.0f) * glm::rotate(-90.0f, 0.0f, 1.0f, 0.0f)*glm::scale(0.01f,0.01f,0.01f);
 	glm::mat4 projection = glm::perspective(45.0f, (float)windowWidth / (float)windowHeight, 0.1f, 1000.0f);
 	glm::mat4 normalMatrix = glm::inverseTranspose(model);
 
@@ -182,19 +177,31 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 		glVertexAttribPointer(normalLocation, 3, GL_FLOAT, GL_FALSE, sizeof(VertexData), (void*)(sizeof(float) * 5));
 		glBindBuffer(GL_ARRAY_BUFFER, 0);
 
-		glBindBuffer(GL_ARRAY_BUFFER, offsetVBO);
-		glEnableVertexAttribArray(offsetLocation);
-		glVertexAttribPointer(offsetLocation, 3, GL_FLOAT, GL_FALSE, sizeof(float)*3, (void*)0);
-		glBindBuffer(GL_ARRAY_BUFFER, 0);
-		glVertexAttribDivisor(offsetLocation, 1);
 
+		model = glm::translate(-1.0f, -0.5f, -3.0f) * glm::rotate(-90.0f, 0.0f, 1.0f, 0.0f)*glm::scale(0.01f, 0.01f, 0.01f);
+		glUniformMatrix4fv(MLocation, 1, GL_FALSE, glm::value_ptr(model));
+		glUniformSubroutinesuiv(GL_FRAGMENT_SHADER, 1, &ambientLightIndex);/*选的你要使用的subroutine*/
 		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ibo);
-		glDrawElementsInstanced(GL_TRIANGLES, indexCount, GL_UNSIGNED_INT, 0,3);
+		glDrawElements(GL_TRIANGLES, indexCount, GL_UNSIGNED_INT,0);
 		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+
+		model = glm::translate(0.0f, -0.5f, -3.0f) * glm::rotate(-90.0f, 0.0f, 1.0f, 0.0f)*glm::scale(0.01f, 0.01f, 0.01f);
+		glUniformMatrix4fv(MLocation, 1, GL_FALSE, glm::value_ptr(model));
+		glUniformSubroutinesuiv(GL_FRAGMENT_SHADER, 1, &diffuseLightIndex);/*选的你要使用的subroutine*/
+		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ibo);
+		glDrawElements(GL_TRIANGLES, indexCount, GL_UNSIGNED_INT, 0);
+		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+
+		model = glm::translate(1.0f, -0.5f, -3.0f) * glm::rotate(-90.0f, 0.0f, 1.0f, 0.0f)*glm::scale(0.01f, 0.01f, 0.01f);
+		glUniformMatrix4fv(MLocation, 1, GL_FALSE, glm::value_ptr(model));
+		glUniformSubroutinesuiv(GL_FRAGMENT_SHADER, 1, &specularLightIndex);/*选的你要使用的subroutine*/
+		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ibo);
+		glDrawElements(GL_TRIANGLES, indexCount, GL_UNSIGNED_INT, 0);
+		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+
 		glUseProgram(0);
 	};
 
-	Timer t2;
 	while (true) {
 		if (PeekMessage(&msg, NULL, NULL, NULL, PM_REMOVE)) {
 			if (msg.message == WM_QUIT) {
@@ -205,12 +212,7 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 		}
 
 		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-		t2.Start();
-		//model = glm::translate(-1.0f, -0.5f, -4.0f) * glm::rotate(-90.0f, 0.0f, 1.0f, 0.0f)*glm::scale(0.01f, 0.01f, 0.01f);
 		what();
-		glFlush();
-
-		printf("cost time %f\n",t2.GetPassedTime()*1000.0f);
 		SwapBuffers(dc);
 	}
 

res/shader/MixLight.fs

@@ -0,0 +1,71 @@
+#version 400 core
+subroutine vec4 SurfaceColor();
+
+uniform sampler2D U_MainTexture;
+subroutine uniform SurfaceColor U_SurfaceColor;
+varying vec3 V_Normal;
+varying vec4 V_WorldPos;//当前的位置
+varying vec2 V_Texcoord;
+
+subroutine (SurfaceColor) vec4 Ambient(){
+	
+	//ambient
+	vec4 AmbientLightColor = vec4(0.4, 0.4, 0.4, 1.0);
+	vec4 AmbientMaterial = vec4(0.2, 0.2, 0.2, 1.0);
+	vec4 AmbientColor = AmbientLightColor*AmbientMaterial;
+
+	vec4 ret = AmbientColor;
+	return ret;
+}
+
+subroutine (SurfaceColor) vec4 Diffuse(){
+	
+	vec3 lightPos = vec3(10.0, 10.0, 0.0);
+	vec3 L=lightPos;
+	L = normalize(L);
+	vec3 n = normalize(V_Normal);
+
+	//ambient
+	vec4 AmbientLightColor = vec4(0.4, 0.4, 0.4, 1.0);
+	vec4 AmbientMaterial = vec4(0.2, 0.2, 0.2, 1.0);
+	vec4 AmbientColor = AmbientLightColor*AmbientMaterial;
+
+	//diffuse
+	vec4 DiffuseLightColor = vec4(1.0,1.0,1.0,1.0);
+	vec4 DiffuseMaterial = vec4(0.8, 0.8, 0.8, 1.0);
+	vec4 diffuseColor = DiffuseLightColor*DiffuseMaterial*max(0.0, dot(L,n));
+
+	vec4 ret = AmbientColor + texture2D(U_MainTexture, V_Texcoord) * diffuseColor;
+	return ret;
+}
+
+subroutine (SurfaceColor) vec4 Specular(){
+	vec3 lightPos = vec3(10.0, 10.0, 0.0);
+	vec3 L=lightPos;
+	L = normalize(L);
+	vec3 n = normalize(V_Normal);
+
+	//ambient
+	vec4 AmbientLightColor = vec4(0.4, 0.4, 0.4, 1.0);
+	vec4 AmbientMaterial = vec4(0.2, 0.2, 0.2, 1.0);
+	vec4 AmbientColor = AmbientLightColor*AmbientMaterial;
+
+	//diffuse
+	vec4 DiffuseLightColor = vec4(1.0,1.0,1.0,1.0);
+	vec4 DiffuseMaterial = vec4(0.8, 0.8, 0.8, 1.0);
+	vec4 diffuseColor = DiffuseLightColor*DiffuseMaterial*max(0.0, dot(L,n));
+
+	//specular
+	vec4 SpecularLightColor = vec4(1.0,1.0,1.0,1.0);
+	vec4 SpecularMaterial = vec4(0.9,0.9,0.9,1.0);
+	vec3 reflectDir = normalize(reflect(-L,n));//-L就是光线的入射方向向量，以法线为基础计算方式向量
+	vec3 viewDir = normalize(vec3(0.0) - V_WorldPos.xyz);//vec3(0.0)表示已中心为观察点，这里求的是眼睛到物体的视线向量
+	vec4 specularColor = SpecularLightColor*SpecularMaterial*pow(max(0.0,dot(viewDir,reflectDir)),128.0);
+
+	vec4 ret = AmbientColor + texture2D(U_MainTexture, V_Texcoord) * diffuseColor + specularColor;
+	return ret;
+}
+
+void main() {
+	gl_FragColor = U_SurfaceColor();
+}

res/shader/MixLight.vs

@@ -0,0 +1,19 @@
+attribute vec3 pos;
+attribute vec2 texcoord;
+attribute vec3 normal;
+
+uniform mat4 M;
+uniform mat4 V;
+uniform mat4 P;
+uniform mat4 NM;
+
+varying vec3 V_Normal;
+varying vec4 V_WorldPos;//µ±Ç°µÄλÖÃ
+varying vec2 V_Texcoord;
+
+void main() {
+	V_Normal = mat3(NM)*normal;
+	V_WorldPos = M * vec4(pos, 1.0);
+	V_Texcoord = texcoord;
+	gl_Position = P*V*M*vec4(pos,1.0);	
+}

shader2.vcxproj

@@ -159,8 +159,8 @@
     <ClInclude Include="timer.h" />
   </ItemGroup>
   <ItemGroup>
-    <None Include="res\shader\diffuse.fs" />
-    <None Include="res\shader\diffuse.vs" />
+    <None Include="res\shader\MixLight.fs" />
+    <None Include="res\shader\MixLight.vs" />
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">

shader2.vcxproj.filters

@@ -46,10 +46,10 @@
     </ClInclude>
   </ItemGroup>
   <ItemGroup>
-    <None Include="res\shader\diffuse.fs">
+    <None Include="res\shader\MixLight.fs">
       <Filter>源文件</Filter>
     </None>
-    <None Include="res\shader\diffuse.vs">
+    <None Include="res\shader\MixLight.vs">
       <Filter>源文件</Filter>
     </None>
   </ItemGroup>