把fob内容绘制到texture

main.cpp

@@ -137,11 +137,11 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 	GLuint colorBuffer, depthBuffer;
 	GLuint fbo = CreateFramebufferObject(colorBuffer, depthBuffer, windowWidth, windowHeight);
 
+	glViewport(0, 0, windowWidth, windowHeight);
+
 	GL_CALL(glClearColor(0.1f, 0.4f, 0.7f, 1.0f));
 	glEnable(GL_DEPTH_TEST);
 
-	glViewport(0,0, windowWidth, windowHeight);
-
 	//创建一个单位矩阵和一个投影矩阵，后面用来传递到shader
 	float identify[] = {
 		1,0,0,0,
@@ -171,7 +171,7 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 		glUniformMatrix4fv(PLocation, 1, GL_FALSE, glm::value_ptr(projection));
 		glUniformMatrix4fv(NMLocation, 1, GL_FALSE, glm::value_ptr(normalMatrix));
 
-		glBindTexture(GL_TEXTURE_2D, mainTexture);
+		glBindTexture(GL_TEXTURE_2D, colorBuffer);
 		glUniform1i(textureLocation, 0);
 
 		glUniformMatrix4fv(MLocation, 1, GL_FALSE, glm::value_ptr(model));
@@ -182,6 +182,12 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 		glUseProgram(0);
 	};
 
+	/*使用固定管线绘制一个四边形，并把fbo内容贴上*/
+	glMatrixMode(GL_PROJECTION);
+	glLoadMatrixf(glm::value_ptr(projection));
+	glMatrixMode(GL_MODELVIEW);
+	glLoadIdentity();
+
 	while (true) {
 		if (PeekMessage(&msg, NULL, NULL, NULL, PM_REMOVE)) {
 			if (msg.message == WM_QUIT) {
@@ -191,8 +197,26 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 			DispatchMessage(&msg);
 		}
 
+		//绘制内容到fbo
+		glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+		GL_CALL(glClearColor(0.1f, 0.4f, 0.7f, 1.0f));
 		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 		what();
+		glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+		//把fbo绘制到一个四边形上
+		GL_CALL(glClearColor(0.5f, 0.4f, 0.7f, 1.0f));
+		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+		glEnable(GL_TEXTURE_2D);
+		glBindTexture(GL_TEXTURE_2D, colorBuffer);
+
+		glBegin(GL_QUADS);
+		glTexCoord2f(0.0f, 0.0f); glVertex3f(-0.5f, -0.5f, -4.0f);
+		glTexCoord2f(1.0f, 0.0f); glVertex3f(0.5f, -0.5f, -4.0f);
+		glTexCoord2f(1.0f, 1.0f); glVertex3f(0.5f, 0.5f, -4.0f);
+		glTexCoord2f(0.0f, 1.0f); glVertex3f(-0.5f, 0.5f, -4.0f);
+		glEnd();
+
 		SwapBuffers(dc);
 	}
 

misc.cpp

@@ -37,8 +37,8 @@ GLuint CreateFramebufferObject(GLuint & colorBuffer, GLuint & depthBuffer, int w
 	glBindTexture(GL_TEXTURE_2D, colorBuffer);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
-	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
 	glBindTexture(GL_TEXTURE_2D, 0);
 	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, colorBuffer, 0);//°ó¶¨¸Õ²ÅÉú³ÉµÄtextureµ½GL_COLOR_ATTACHMENT0
@@ -50,7 +50,7 @@ GLuint CreateFramebufferObject(GLuint & colorBuffer, GLuint & depthBuffer, int w
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
-	glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, width, height, 0, GL_RGBA, GL_DEPTH_COMPONENT, nullptr);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, width, height, 0, GL_DEPTH_COMPONENT, GL_FLOAT, nullptr);
 	glBindTexture(GL_TEXTURE_2D, 0);
 	glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, depthBuffer, 0);
 
@@ -61,7 +61,7 @@ GLuint CreateFramebufferObject(GLuint & colorBuffer, GLuint & depthBuffer, int w
 	}
 
 	glBindFramebuffer(GL_FRAMEBUFFER, 0);
-	return GLuint();
+	return fbo;
 }
 
 char* LoadFileContent(const char *path) {