使用cpu绘制全屏四边型

main.cpp

@@ -52,19 +52,18 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 	}
 
 	/*创建窗口*/
-	//调整窗口大小
-	RECT rect;
-	rect.left = 0;
-	rect.right = 800;
-	rect.top = 0;
-	rect.bottom = 600;
-	AdjustWindowRect(&rect, WS_EX_OVERLAPPEDWINDOW, NULL);
-	int windowWidth = rect.right - rect.left;
-	int windowHeight = rect.bottom - rect.top;
+	int windowWidth = 800;
+	int windowHeight = 600;
 
 	//窗口名称一定要和刚才注册窗口的保持一致
 	HWND hwnd = CreateWindowEx(NULL, L"GLWindow", L"OpenGL Window", WS_OVERLAPPEDWINDOW, 100, 100, windowWidth, windowHeight, NULL, NULL, hinstance, NULL);
 
+	//获取实际窗口大小
+	RECT rect;
+	GetClientRect(hwnd, &rect);
+	windowWidth = rect.right - rect.left;
+	windowHeight = rect.bottom - rect.top;
+
 	//设置渲染环境
 	HDC dc = GetDC(hwnd);//获取设备上下文
 	PIXELFORMATDESCRIPTOR pfd;
@@ -88,7 +87,7 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 	glewInit();
 
 	/*创建program*/
-	GLuint program = CreateGPUProgram("res/shader/test.vs", "res/shader/test.fs");
+	GLuint program = CreateGPUProgram("res/shader/UI.vs", "res/shader/UI.fs");
 
 	GLuint posLocation, texcoordLocation, normalLocation, MLocation, VLocation, PLocation, NMLocation, textureLocation;
 	posLocation = glGetAttribLocation(program, "pos");
@@ -104,12 +103,33 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 	/*load model*/
 	unsigned int *indexes = nullptr;
 	int vertexCount = 0, indexCount = 0;
-	VertexData* vertexes = LoadObjModel("res/model/Sphere.obj", &indexes, vertexCount, indexCount);
+	VertexData* vertexes = LoadObjModel("res/model/Quad.obj", &indexes, vertexCount, indexCount);
 
 	if (vertexes == nullptr) {
 		printf("load obj model fail\n");
 	}
 
+	float z = 4.0f;
+	float halfFOV = 22.5f;
+	float randianHalfFOV = 3.14 * halfFOV / 180.0f;//角度转弧度
+	float tanHalfFOV = sinf(randianHalfFOV) / cosf(randianHalfFOV);
+	float y = tanHalfFOV * z;
+	float aspect = (float)windowWidth / (float)windowHeight;
+	float x = y * aspect;
+
+	vertexes[0].position[0] = -x;
+	vertexes[0].position[1] = -y;
+
+	vertexes[1].position[0] = x;
+	vertexes[1].position[1] = -y;
+
+	vertexes[2].position[0] = -x;
+	vertexes[2].position[1] = y;
+
+	vertexes[3].position[0] = x;
+	vertexes[3].position[1] = y;
+
+
 	/*创建vbo*/
 	GLuint vbo = CreateBufferObject(GL_ARRAY_BUFFER, sizeof(VertexData) * vertexCount, GL_STATIC_DRAW, vertexes);
 
@@ -122,6 +142,7 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 
 	glClearColor(0.0f, 0.0f, 0.0f, 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[] = {
@@ -130,8 +151,9 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 		0,0,1,0,
 		0,0,0,1
 	};
+
 	glm::mat4 model = glm::translate(0.0f, 0.0f, -4.0f);
-	glm::mat4 projection = glm::perspective(45.0f, 800.0f/600.0f, 0.1f, 1000.0f);
+	glm::mat4 projection = glm::perspective(45.0f, (float)windowWidth / (float)windowHeight, 0.1f, 1000.0f);
 	glm::mat4 normalMatrix = glm::inverseTranspose(model);
 
 	/*显示窗口*/
@@ -141,7 +163,6 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 	/*监听并处理用户请求*/
 	MSG msg;
 
-	float angle = 0.0;
 	while (true) {
 		if (PeekMessage(&msg, NULL, NULL, NULL, PM_REMOVE)) {
 			if (msg.message == WM_QUIT) {
@@ -151,13 +172,6 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 			DispatchMessage(&msg);
 		}
 
-		if (angle > 360) {
-			angle = 0;
-		}
-		else {
-			angle += 0.01f;
-		}
-		model = glm::translate(0.0f, 0.0f, -4.0f) * glm::rotate(angle, 0.0f, 1.0f, 0.0f);
 		glm::mat4 normalMatrix = glm::inverseTranspose(model);
 
 		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
@@ -168,7 +182,7 @@ 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, secondTexture);
+		glBindTexture(GL_TEXTURE_2D, mainTexture);
 		glUniform1i(textureLocation, 0);
 
 		glBindBuffer(GL_ARRAY_BUFFER, vbo);

res/shader/UI.fs

@@ -0,0 +1,6 @@
+uniform sampler2D U_MainTexture;
+varying vec2 V_Texcoord;
+
+void main() {
+	gl_FragColor = texture2D(U_MainTexture, V_Texcoord);
+}

res/shader/UI.vs

@@ -0,0 +1,16 @@
+attribute vec3 pos;
+attribute vec2 texcoord;
+attribute vec3 normal;
+
+uniform mat4 M;
+uniform mat4 V;
+uniform mat4 P;
+uniform mat4 NM;
+
+varying vec2 V_Texcoord;
+
+void main() {
+	//V_Texcoord = vec2(texcoord.x, 1.0-texcoord.y);
+	V_Texcoord = vec2(texcoord.x, texcoord.y);
+	gl_Position = P*V*M*vec4(pos,1.0);	
+}

shader2.vcxproj

@@ -157,6 +157,8 @@
   <ItemGroup>
     <None Include="res\shader\test.fs" />
     <None Include="res\shader\test.vs" />
+    <None Include="res\shader\UI.fs" />
+    <None Include="res\shader\UI.vs" />
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">

shader2.vcxproj.filters

@@ -40,5 +40,11 @@
     <None Include="res\shader\test.vs">
       <Filter>源文件</Filter>
     </None>
+    <None Include="res\shader\UI.fs">
+      <Filter>源文件</Filter>
+    </None>
+    <None Include="res\shader\UI.vs">
+      <Filter>源文件</Filter>
+    </None>
   </ItemGroup>
 </Project>