I've got an issue with opening an OpenGL window from my application.
I am using a 64bit console application, and from within that console I want to open another window for OpenGL to draw into.
The call fails at CreateWindowEx(), and fails with "MyApp.exe has triggered a breakpoint" Following code initializes the window itself.
bool OpenGL_Display::CreateGLWindow(char* title, int width, int height, int bits, bool fullscreenflag, int posX, int posY)
{
GLuint PixelFormat; // Holds The Results After Searching For A Match
WNDCLASS wc; // Windows Class Structure
DWORD dwExStyle; // Window Extended Style
DWORD dwStyle; // Window Style
RECT WindowRect; // Grabs Rectangle Upper Left / Lower Right Values
WindowRect.left=(long)0; // Set Left Value To 0
WindowRect.right=(long)width; // Set Right Value To Requested Width
WindowRect.top=(long)0; // Set Top Value To 0
WindowRect.bottom=(long)height; // Set Bottom Value To Requested Height
hInstance = GetModuleHandle(NULL); // Grab An Instance For Our Window
wc.style = CS_HREDRAW | CS_VREDRAW | CS_OWNDC; // Redraw On Size, And Own DC For Window.
wc.lpfnWndProc = NULL; // WndProc Handles Messages
wc.cbClsExtra = 0; // No Extra Window Data
wc.cbWndExtra = 0; // No Extra Window Data
wc.hInstance = hInstance; // Set The Instance
wc.hIcon = LoadIcon(NULL, IDI_WINLOGO); // Load The Default Icon
wc.hCursor = LoadCursor(NULL, IDC_ARROW); // Load The Arrow Pointer
wc.hbrBackground = NULL; // No Background Required For GL
wc.lpszMenuName = NULL; // We Don't Want A Menu
wc.lpszClassName = "OpenGL"; // Set The Class Name
if (!RegisterClass(&wc)) // Attempt To Register The Window Class
{
MessageBox(NULL,"Failed To Register The Window Class.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
dwExStyle=WS_EX_APPWINDOW | WS_EX_WINDOWEDGE; // Window Extended Style
dwStyle=WS_OVERLAPPEDWINDOW; // Windows Style
AdjustWindowRectEx(&WindowRect, dwStyle, FALSE, dwExStyle); // Adjust Window To True Requested Size
HWND hwndC = GetConsoleWindow();
// Create The Window
if (!(hWnd=CreateWindowEx( dwExStyle, // Extended Style For The Window
"OpenGL", // Class Name
title, // Window Title
dwStyle | // Defined Window Style
WS_CLIPSIBLINGS | // Required Window Style
WS_CLIPCHILDREN, // Required Window Style
0, 0, // Window Position
WindowRect.right-WindowRect.left, // Calculate Window Width
WindowRect.bottom-WindowRect.top, // Calculate Window Height
hwndC, // No Parent Window
NULL, // No Menu
hInstance, // Instance
NULL))) // Dont Pass Anything To WM_CREATE
{
KillGLWindow(); // Reset The Display
MessageBox(NULL,"Window Creation Error.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE; // Return FALSE
}
}
The previous code leading to it:
extern "C" __declspec(dllexport) void OpenGLDisplay_Init(int width, int height, int posX, int posY)
{
oglDisp.Init_Display(width, height, posX, posY);
}
void OpenGL_Display::Init_Display(int width, int height, int posX, int posY)
{
if (!CreateGLWindow("Ophthametrics Live Display", width, height, 24, false, posX, posY))
{
throw;
}
}
What is going wrong in there? I have no idea, and I was using code I used for another application, which worked just fine. Here though it just fails horribly (in the original code it was no console application, but rather a Win32 application without the console).
The final solution would be in a DLL which is called and once it gets called, it should create a window for OpenGL to draw into.
"What if you point your window proc at a real function?"
Written by slugo, that did it.