#include <windows.h>
#include <gl/GL.h>
#include <gl/GLU.h>
#pragma comment(lib,"opengl32.lib")
#pragma comment(lib,"glu32.lib")
LRESULT CALLBACK GLWindowProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
switch (msg)
{
case WM_CLOSE:
PostQuitMessage(0);
break;
}
return DefWindowProc(hwnd, msg, wParam, lParam);
}
INT WINAPI WinMain(_In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance, _In_ LPSTR lpCmdLine, _In_ int nShowCmd)
{
//register window
WNDCLASSEX wndclass;
wndclass.cbClsExtra = 0;
wndclass.cbSize = sizeof(WNDCLASSEX);
wndclass.cbWndExtra = 0;
wndclass.hbrBackground = NULL;
wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
wndclass.hIcon = NULL;
wndclass.hIconSm = NULL;
wndclass.hInstance = hInstance;
wndclass.lpfnWndProc = GLWindowProc;
wndclass.lpszClassName = L"GLWindow";
wndclass.lpszMenuName = NULL;
wndclass.style = CS_VREDRAW | CS_HREDRAW;
ATOM atom = RegisterClassEx(&wndclass);
if (!atom)
{
return 0;
}
//create window
HWND hwnd = CreateWindowEx(NULL, L"GLWindow", L"OpenGL Window", WS_OVERLAPPEDWINDOW,
100, 100, 800, 600, NULL, NULL, hInstance, NULL);
//create opengl render context
HDC dc = GetDC(hwnd);
PIXELFORMATDESCRIPTOR pfd;
memset(&pfd, 0, sizeof(PIXELFORMATDESCRIPTOR));
pfd.nVersion = 1;
pfd.nSize = sizeof(PIXELFORMATDESCRIPTOR);
pfd.cColorBits = 32;
pfd.cDepthBits = 24;
pfd.cStencilBits = 8;
pfd.iPixelType = PFD_TYPE_RGBA;
pfd.iLayerType = PFD_MAIN_PLANE;
pfd.dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER;
int pixelFormat = ChoosePixelFormat(dc, &pfd);
SetPixelFormat(dc, pixelFormat, &pfd);
HGLRC rc = wglCreateContext(dc);
wglMakeCurrent(dc, rc);//setup opengl context complete
//opengl init
glMatrixMode(GL_PROJECTION);//tell the gpu processer that i would select the projection matrix
gluPerspective(50.0f, 800.0f / 600.0f, 0.1f, 1000.0f);//set some values to projection matrix
glMatrixMode(GL_MODELVIEW);//tell .... model view matrix
glLoadIdentity();
glClearColor(0.1f, 0.4f, 0.6f, 1.0f);//set "clear color" for background
//show window
ShowWindow(hwnd, SW_SHOW);
UpdateWindow(hwnd);
glEnable(GL_CULL_FACE);//逆时针方向为正面
//front face : ccw -> counter clock wind
//glFrontFace(GL_CW);设置顺时针为正面
MSG msg;
while (true)
{
if (PeekMessage(&msg, NULL, NULL, NULL, PM_REMOVE))
{
if (msg.message == WM_QUIT)
{
break;
}
TranslateMessage(&msg);
DispatchMessage(&msg);
}
//draw scene
glClear(GL_COLOR_BUFFER_BIT);
glBegin(GL_TRIANGLE_FAN);//start to draw something n-2
/*
* Bengin和End间
* GL_TRIANGLE,每三个点组成一个三角形
* GL_TRIANGLE_STRIP ，如果遇到第一个点是奇数点连接会用n+1,n+2,n+3
* 组成三角形，偶数点时候连接顺序N+1->N->N+2（二者选点统一）
* GL_TRIANGLE_FAN,每个三角形都以第一个点为原点.
*/
glColor4ub(255, 0, 0, 255);
glVertex3f(0.0f, 0.0f, -10.0f);
glColor4ub(0, 0, 255, 255);
glVertex3f(-5.0f, -2.0f, -10.0f);
glColor4ub(0, 255, 0, 255);
glVertex3f(-3.0f, -2.0f, -10.0f);
glColor4ub(0, 0, 255, 255);
glVertex3f(-1.0f, -2.0f, -10.0f);
glColor4ub(0, 255, 255, 255);
glVertex3f(2.0f, -2.0f, -10.0f);
glEnd();//end
//present scene
SwapBuffers(dc);
}
return 0;
}
