/* * menu.c * * WGL/OpenGL program * * Copyright (C) 1997 by Nate Robins (ndr@pobox.com) * * This program is freely distributable without licensing fees and is * provided without guarantee or warrantee expressed or implied. This * program is not in the public domain. */ /* includes */ #include /* must include this before GL/gl.h */ #include /* OpenGL header file */ #include /* pragmas */ #pragma warning(disable : 4244) /* disable conversion warnings */ /* globals */ BOOL Rotate = TRUE; /* rotating? */ HMENU hPopup = NULL; /* popup menu */ /* functions */ /* WindowProc() * Minimum Window Procedure */ LONG WINAPI WindowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam) { LONG lRet = 1; PAINTSTRUCT ps; POINT point; switch(uMsg) { case WM_CREATE: break; case WM_DESTROY: break; case WM_PAINT: BeginPaint(hWnd, &ps); EndPaint(hWnd, &ps); break; case WM_RBUTTONDOWN: point.x = LOWORD(lParam); point.y = HIWORD(lParam); ClientToScreen(hWnd, &point); TrackPopupMenu(hPopup, TPM_LEFTALIGN, point.x, point.y, 0, hWnd, NULL); break; case WM_CHAR: if(wParam == 27) /* ESC */ PostQuitMessage(0); break; case WM_SIZE: glViewport(0, 0, LOWORD(lParam), HIWORD(lParam)); break; case WM_COMMAND: printf("WM_COMMAND: %c\n", LOWORD(wParam)); switch(LOWORD(wParam)) { case 's': Rotate = FALSE; break; case 'r': Rotate = TRUE; break; case 'x': PostQuitMessage(0); break; } break; case WM_CLOSE: PostQuitMessage(0); break; default: lRet = DefWindowProc(hWnd, uMsg, wParam, lParam); break; } return lRet; } /* oglCreateWindow * Create a window suitable for OpenGL rendering */ HWND oglCreateWindow(char* title, int x, int y, int width, int height) { WNDCLASS wc; HWND hWnd; HINSTANCE hInstance; /* get this modules instance */ hInstance = GetModuleHandle(NULL); /* fill in the window class structure */ wc.style = 0; /* no special styles */ wc.lpfnWndProc = (WNDPROC)WindowProc; /* event handler */ wc.cbClsExtra = 0; /* no extra class data */ wc.cbWndExtra = 0; /* no extra window data */ wc.hInstance = hInstance; /* instance */ wc.hIcon = LoadIcon(NULL, IDI_WINLOGO); /* load a default icon */ wc.hCursor = LoadCursor(NULL, IDC_ARROW); /* load a default cursor */ wc.hbrBackground = NULL; /* redraw our own bg */ wc.lpszMenuName = NULL; /* no menu */ wc.lpszClassName = title; /* use a special class */ /* register the window class */ if (!RegisterClass(&wc)) { MessageBox(NULL, "RegisterClass() failed: Cannot register window class,", "Error", MB_OK); return NULL; } /* create a window */ hWnd = CreateWindow(title, /* class */ title, /* title (caption) */ WS_OVERLAPPEDWINDOW | /* resize handles, etc */ WS_CLIPSIBLINGS | WS_CLIPCHILDREN, /* style */ x, y, width, height, /* dimensions */ NULL, /* no parent */ NULL, /* no menu */ hInstance, /* instance */ NULL); /* don't pass anything to WM_CREATE */ /* make sure we got a window */ if (hWnd == NULL) { MessageBox(NULL, "CreateWindow() failed: Cannot create a window.", "Error", MB_OK); return NULL; } /* show the window (map it) */ ShowWindow(hWnd, SW_SHOW); /* send an initial WM_PAINT message (expose) */ UpdateWindow(hWnd); return hWnd; } /* oglPixelFormat() * Sets the pixel format for the context */ int oglSetPixelFormat(HDC hDC, BYTE type, DWORD flags) { int pf; PIXELFORMATDESCRIPTOR pfd; /* fill in the pixel format descriptor */ pfd.nSize = sizeof(PIXELFORMATDESCRIPTOR); pfd.nVersion = 1; /* version (should be 1) */ pfd.dwFlags = PFD_DRAW_TO_WINDOW | /* draw to window (not bitmap) */ PFD_SUPPORT_OPENGL | /* draw using opengl */ flags; /* user supplied flags */ pfd.iPixelType = type; /* PFD_TYPE_RGBA or COLORINDEX */ pfd.cColorBits = 24; /* get the appropriate pixel format */ pf = ChoosePixelFormat(hDC, &pfd); if (pf == 0) { MessageBox(NULL, "ChoosePixelFormat() failed: Cannot find format specified.", "Error", MB_OK); return 0; } /* set the pixel format */ if (SetPixelFormat(hDC, pf, &pfd) == FALSE) { MessageBox(NULL, "SetPixelFormat() failed: Cannot set format specified.", "Error", MB_OK); return 0; } return pf; } /* menubar() * create a menubar for the window */ void menubar(HWND hWnd) { HMENU hFileMenu; /* file menu handle */ HMENU hDrawMenu; /* draw menu handle */ HMENU hMenu; /* menu bar handle */ MENUITEMINFO item; /* item info */ /* create the menus */ hMenu = CreateMenu(); hFileMenu = CreateMenu(); hDrawMenu = CreateMenu(); /* fill up the file menu */ item.cbSize = sizeof(MENUITEMINFO); item.fMask = MIIM_ID | MIIM_TYPE | MIIM_SUBMENU; item.fType = MFT_STRING; item.hSubMenu = NULL; item.wID = 'x'; item.dwTypeData = "E&xit"; item.cch = strlen("E&xit"); InsertMenuItem(hFileMenu, 0, FALSE, &item); /* now do the draw menu */ item.wID = 'r'; item.dwTypeData = "&Rotate"; item.cch = strlen("&Rotate"); InsertMenuItem(hDrawMenu, 0, FALSE, &item); item.wID = 's'; item.dwTypeData = "&Don't Rotate"; item.cch = strlen("&Don't Rotate"); InsertMenuItem(hDrawMenu, 1, FALSE, &item); /* now do the main menu */ item.wID = 0; item.dwTypeData = "&File"; item.cch = strlen("&File"); item.hSubMenu = hFileMenu; InsertMenuItem(hMenu, 0, FALSE, &item); item.wID = 0; item.dwTypeData = "&Draw"; item.cch = strlen("&Draw"); item.hSubMenu = hDrawMenu; InsertMenuItem(hMenu, 1, FALSE, &item); /* attach the menu to the window */ SetMenu(hWnd, hMenu); /* use the draw menu as a popup menu */ hPopup = hDrawMenu; } /* main() * Entry point */ int main(int argc, char** argv) { HDC hDC; /* device context */ HGLRC hRC; /* opengl context */ HWND hWnd; /* window */ MSG msg; /* message */ /* create a window */ hWnd = oglCreateWindow("OpenGL", 0, 0, 200, 200); if (hWnd == NULL) exit(1); /* set up a menu bar */ menubar(hWnd); /* get the device context */ hDC = GetDC(hWnd); /* set the pixel format */ if (oglSetPixelFormat(hDC, PFD_TYPE_RGBA, PFD_DOUBLEBUFFER) == 0) exit(1); /* create an OpenGL context */ hRC = wglCreateContext(hDC); wglMakeCurrent(hDC, hRC); /* now we can start changing state & rendering */ while (1) { /* first, check for (and process) messages in the queue */ while(PeekMessage(&msg, hWnd, 0, 0, PM_NOREMOVE)) { if(GetMessage(&msg, hWnd, 0, 0)) { TranslateMessage(&msg); /* translate virtual-key messages */ DispatchMessage(&msg); /* call the window proc */ } else { goto quit; } } /* draw and possibly rotate a triangle around */ glClear(GL_COLOR_BUFFER_BIT); if(Rotate) glRotatef(1.0, 0.0, 0.0, 1.0); glBegin(GL_TRIANGLES); glColor3f(1.0, 0.0, 0.0); glVertex2i( 0, 1); glColor3f(0.0, 1.0, 0.0); glVertex2i(-1, -1); glColor3f(0.0, 0.0, 1.0); glVertex2i( 1, -1); glEnd(); glFlush(); SwapBuffers(hDC); /* nop if singlebuffered */ } quit: /* clean up */ wglMakeCurrent(NULL, NULL); /* make our context 'un-'current */ ReleaseDC(hDC, hWnd); /* release handle to DC */ wglDeleteContext(hRC); /* delete the rendering context */ DestroyWindow(hWnd); /* destroy the window */ return 0; }