shader2/main.cpp

#define _CRT_SECURE_NO_WARNINGS
#include <windows.h>
#include "glew.h"
#include <gl/GL.h>
#include <stdio.h>
#pragma comment(lib,"opengl32.lib")
#pragma comment(lib, "glew32.lib")

struct Vertex {
	float pos[3];
	float color[4];
};

/**
* @hwnd ������Ϣ�Ĵ���
* @msg ��Ϣ����
*/
LRESULT CALLBACK GLWindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {
	switch (msg) {
	case WM_CLOSE:
		PostQuitMessage(0);
		return 0;
	}

	return DefWindowProc(hwnd, msg, wParam, lParam);//������Ϣ����windowĬ�ϴ�������
}

char* LoadFileContent(const char *path) {
	char* fileContent = nullptr;
	int filesize = 0;
	FILE*pFile = fopen(path, "rb");
	if (pFile) {
		fseek(pFile, 0, SEEK_END);
		int nLen = ftell(pFile);
		if (nLen > 0) {
			rewind(pFile);
			fileContent = new char[nLen + 1];
			fread(fileContent, sizeof(char), nLen, pFile);
			fileContent[nLen] = '\0';
			filesize = nLen;
		}
		fclose(pFile);
	}
	return fileContent;
}

/**
* ����һ��GPU����
*/
GLuint CreateGPUProgram(const char* vsShaderPath, const char* fsShaderPath) {
	//����program
	GLuint program = glCreateProgram();

	//����shader
	GLuint vsShader = glCreateShader(GL_VERTEX_SHADER);
	GLuint fsShader = glCreateShader(GL_FRAGMENT_SHADER);
	//��ȡshader����
	const char* vsCode = LoadFileContent(vsShaderPath);
	const char* fsCode = LoadFileContent(fsShaderPath);
	//��shader���� ���ڴ洫���Դ�
	glShaderSource(vsShader, 1, &vsCode, nullptr);
	glShaderSource(fsShader, 1, &fsCode, nullptr);
	//����shader
	glCompileShader(vsShader);
	glCompileShader(fsShader);
	
	//����shader
	glAttachShader(program, vsShader);
	glAttachShader(program, fsShader);

	//����
	glLinkProgram(program);

	//����shader
	glDetachShader(program, vsShader);
	glDetachShader(program, fsShader);

	//ɾ��shader
	glDeleteShader(vsShader);
	glDeleteShader(fsShader);

	return program;
}
/**
* @hinstance ��Ӧ�ó�������ʵ��
* @hPrevInstance ��һ��Ӧ�ó�ʽ��ʵ��
* @IpCmdLine �����еIJ���
* @ShowCmd ��ô��ʾ����
*/
INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd)
{
	/*ע�ᴰ��*/
	WNDCLASSEX wndclass;
	wndclass.cbClsExtra = 0; //�������͵Ķ����ռ䣬���ﲻ��Ҫ
	wndclass.cbSize = sizeof(WNDCLASSEX); //����ʵ��ռ�õ��ڴ�
	wndclass.cbWndExtra = 0; //���ڵĶ����ռ䣬���ﲻ��Ҫ
	wndclass.hbrBackground = NULL; //���ڱ���
	wndclass.hCursor = LoadCursor(NULL, IDC_ARROW); //������������
	wndclass.hIcon = NULL; //Ӧ�ó���exe�ļ���ʾͼ��
	wndclass.hIconSm = NULL; //Ӧ�ó�������ʱ���Ͻ�ͼ��
	wndclass.hInstance = hinstance; //��Ӧ�ó���ʵ��
	wndclass.lpfnWndProc = GLWindowProc; //�����û������˴��ڣ��������ᱻ����
	wndclass.lpszClassName = L"GLWindow";//��������
	wndclass.lpszMenuName = NULL;//�˵�����
	wndclass.style = CS_VREDRAW | CS_HREDRAW;//���ڸ���ʱ���ػ淽ʽ������ʹ�ô�ֱ�ػ���ˮƽ�ػ�
	ATOM atom = RegisterClassEx(&wndclass);
	if (!atom) {
		MessageBox(NULL, L"Register failed", L"Error", MB_OK);
		return  0;
	}

	/*��������*/
	//�������ڴ�С
	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;

	//��������һ��Ҫ�͸ղ�ע�ᴰ�ڵı���һ��
	HWND hwnd = CreateWindowEx(NULL, L"GLWindow", L"OpenGL Window", WS_OVERLAPPEDWINDOW, 100, 100, windowWidth, windowHeight, NULL, NULL, hinstance, NULL);

	//������Ⱦ����
	HDC dc = GetDC(hwnd);//��ȡ�豸������
	PIXELFORMATDESCRIPTOR pfd;
	memset(&pfd, 0, sizeof(PIXELFORMATDESCRIPTOR));
	pfd.nVersion = 1;
	pfd.nSize = sizeof(PIXELFORMATDESCRIPTOR);
	pfd.cColorBits = 32; //��ɫ������ÿ������Ϊ32����4ͨ��RGBA
	pfd.cDepthBits = 24; //���Ȼ�����ÿ�����ش�С��24���ر�ʾһ��������
	pfd.cStencilBits = 8; //�ɰ建����ÿ����Ϊ8����
	pfd.iPixelType = PFD_TYPE_RGBA; //������������ΪRGBA
	pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER; //��ʾ������������������
																			  //�������ظ�ʽ
	int pixelFormat = ChoosePixelFormat(dc, &pfd);
	SetPixelFormat(dc, pixelFormat, &pfd);

	//����OpenGL��Ⱦ����
	HGLRC rc = wglCreateContext(dc);
	wglMakeCurrent(dc, rc);//����OpenGL��Ⱦ������Ч

	/*glew��ʼ��*/
	glewInit();

	/*����program*/
	GLuint program = CreateGPUProgram("test.vs", "test.fs");

	/*����vbo*/
	Vertex vertex[3];

	vertex[0].pos[0] = 0;
	vertex[0].pos[1] = 0;
	vertex[0].pos[2] = -100.0f;
	vertex[0].color[0] = 1.0f;
	vertex[0].color[1] = 1.0f;
	vertex[0].color[2] = 1.0f;
	vertex[0].color[3] = 1.0f;

	vertex[1].pos[0] = 10;
	vertex[1].pos[1] = 0;
	vertex[1].pos[2] = -100.0f;
	vertex[1].color[0] = 1.0f;
	vertex[1].color[1] = 1.0f;
	vertex[1].color[2] = 1.0f;
	vertex[1].color[3] = 1.0f;

	vertex[2].pos[0] = 0;
	vertex[2].pos[1] = 10;
	vertex[2].pos[2] = -100.0f;
	vertex[2].color[0] = 1.0f;
	vertex[2].color[1] = 1.0f;
	vertex[2].color[2] = 1.0f;
	vertex[2].color[3] = 1.0f;
	GLuint vbo;
	glGenBuffers(1, &vbo);
	glBindBuffer(GL_ARRAY_BUFFER, vbo);
	glBufferData(GL_ARRAY_BUFFER, sizeof(float)*7*3, vertex, GL_STATIC_DRAW);
	glBindBuffer(GL_ARRAY_BUFFER, 0);

	glClearColor(1.0f, 1.0f, 0.0f, 1.0f);

	/*��ʾ����*/
	ShowWindow(hwnd, SW_SHOW);
	UpdateWindow(hwnd);

	/*�����������û�����*/
	MSG msg;
	while (true) {
		if (PeekMessage(&msg, NULL, NULL, NULL, PM_REMOVE)) {
			if (msg.message == WM_QUIT) {
				break;
			}
			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}

		glClear(GL_COLOR_BUFFER_BIT);

		SwapBuffers(dc);
	}

	return 0;
}