使用fullscreenquad,渲染rbg cube

Res/fullscreenquad.fs

@@ -0,0 +1,9 @@
+#ifdef GL_ES
+precision mediump float;
+#endif
+varying vec2 V_Texcoord;
+uniform sampler2D U_Texture;
+
+void main(){
+	gl_FragColor = texture2D(U_Texture, V_Texcoord);
+}

Res/fullscreenquad.vs

@@ -0,0 +1,10 @@
+#ifdef GL_ES
+precision mediump float;
+#endif
+attribute vec4 position;
+attribute vec4 texcoord;
+varying vec2 V_Texcoord;
+void main(){
+	V_Texcoord = texcoord.xy;
+	gl_Position = position;
+}

Res/gray.fs

@@ -0,0 +1,11 @@
+#ifdef GL_ES
+precision mediump float;
+#endif
+varying vec2 V_Texcoord;
+uniform sampler2D U_Texture;
+void main()
+{
+	vec4 color=texture2D(U_Texture,V_Texcoord);
+	float gray=(color.r+color.g+color.b)/3.0;
+	gl_FragColor=vec4(gray,gray,gray,1.0);
+}

framebufferobject.cpp

@@ -31,7 +31,7 @@ void FrameBufferObject::AttachDepthBuffer(const char * bufferName, int width, in
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-	glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, width, height, 0, GL_DEPTH_COMPONENT, depthMap, 0);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, width, height, 0, GL_DEPTH_COMPONENT, GL_FLOAT, NULL);
 	glBindTexture(GL_TEXTURE_2D, 0);
 	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthMap, 0);
 	mBuffers.insert(std::pair<std::string, GLuint>(bufferName, depthMap));

renderFramework.vcxproj

@@ -149,6 +149,9 @@
     <ClInclude Include="vertexbuffer.h" />
   </ItemGroup>
   <ItemGroup>
+    <None Include="Res\fullscreenquad.fs" />
+    <None Include="Res\fullscreenquad.vs" />
+    <None Include="Res\gray.fs" />
     <None Include="Res\rgbcube.fs" />
     <None Include="Res\rgbcube.vs" />
   </ItemGroup>

renderFramework.vcxproj.filters

@@ -68,5 +68,14 @@
     <None Include="Res\rgbcube.vs">
       <Filter>源文件</Filter>
     </None>
+    <None Include="Res\fullscreenquad.fs">
+      <Filter>源文件</Filter>
+    </None>
+    <None Include="Res\fullscreenquad.vs">
+      <Filter>源文件</Filter>
+    </None>
+    <None Include="Res\gray.fs">
+      <Filter>源文件</Filter>
+    </None>
   </ItemGroup>
 </Project>

scene.cpp

@@ -1,26 +1,43 @@
 #include "scene.h"
 #include "utils.h"
 #include "model.h"
+#include "framebufferobject.h"
+#include "fullscreenquad.h"
 
 glm::mat4 viewMatrix, projectionMatrix;
 glm::vec3 cameraPos(4.0f, 3.0f, 4.0f);
 Model model;
+FrameBufferObject *fbo;
+FullScreenQuad *fsq;
+
 void Init()
 {
 	model.Init("Res/Cube.obj");
 	model.mShader->Init("Res/rgbcube.vs", "Res/rgbcube.fs");
 	model.SetPosition(0.0f, 0.0f, 0.0f);
 	viewMatrix = glm::lookAt(cameraPos, glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, 1.0f, 0.0f));
+	fsq = new FullScreenQuad();
+	fsq->Init();
+	fsq->mShader->Init("Res/fullscreenquad.vs", "Res/gray.fs");
 }
 
 void SetViewPortSize(float width, float height)
 {
 	projectionMatrix = glm::perspective(50.0f, width/height, 0.1f, 1000.0f);
+	fbo = new FrameBufferObject();
+	fbo->AttachColorBuffer("color", GL_COLOR_ATTACHMENT0, (int)width, (int)height);
+	fbo->AttachDepthBuffer("depth", (int)width, (int)height);
+	fbo->Finish();
+
+	fbo->Bind();
+	model.Draw(viewMatrix, projectionMatrix, cameraPos.x, cameraPos.y, cameraPos.z);
+	fbo->Unbind();
 }
 
 void Draw()
 {
 	glClearColor(0.0f,0.0f,0.0f,1.0f);
 	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-	model.Draw(viewMatrix, projectionMatrix, cameraPos.x, cameraPos.y, cameraPos.z);
+	fsq->mShader->SetTexture("U_Texture", fbo->GetBuffer("color"));
+	fsq->Draw();
 }