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GL_aLpHa

OpenGL OpenGL Scene Won't Work

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Hello there! I am finally coming back to OpenGL after a break from programming all together. I never really got deep into programming in OpenGL except for copy NeHe's basecode and editing it for the fun of it. Now, I've just wrote basic code to display a triangle, to get the form of a basic OpenGL Window down again. My only problem is that the triangle is not being displayed... the window's fine.
[SOURCE]
#define WIN32_LEAN_AND_MEAN

#include <windows.h>
#include <gl/gl.h>
#include <gl/glu.h>
#include <gl/glaux.h>
using namespace std;

//Globals
static HGLRC  g_hRC;                  // rendering context
static HDC    g_hDC;                  // the device context

// Rezize GL Scene
void ResizeGLScene(int width, int height)
{                        
     if(height = 0)            // dont want to divide by zero
     {
               height = 1;
     }
                            
     //reset viewport to new dimensions
     glViewport(0, 0, width, height);
     glMatrixMode(GL_PROJECTION);    // select projection matrix
     glLoadIdentity();               // reset projection matrix
                            
     // calculate aspect ratio of window
     gluPerspective(45.0f, (GLfloat)width/(GLfloat)height, 1.0f, 1000.0f);
                            
     glMatrixMode(GL_MODELVIEW);
     glLoadIdentity();
}   
  
// RenderGLScene
void RenderGLScene()
{
     float angle = 0.0f;   
     
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     glLoadIdentity();
     
     angle += 0.1f;
     if(angle >= 360.0f)
     {
              angle = 0.0f;
     }
     
     glTranslatef(0.0f, 0.0f, -5.0f);
     glRotatef(angle, 0.0f, 0.0f, 0.0f);                // rotate along z-axis
     
     glColor3f(1.0f, 1.0f, 1.0f);
     glBegin(GL_TRIANGLES);
         glVertex3f(-1.0f,-1.0f, 0.0f);
         glVertex3f( 1.0f,-1.0f, 0.0f);
         glVertex3f( 0.0f, 1.0f, 0.0f);
     glEnd();
     
     SwapBuffers(g_hDC);
}

// Sets up the pixel format descriptor
void SetupPixelFormat(HDC hDC)
{
     int nPixelFormat;
     
     static PIXELFORMATDESCRIPTOR pfd = { sizeof(PIXELFORMATDESCRIPTOR),
                                          1,
                                          PFD_DRAW_TO_WINDOW |
                                          PFD_SUPPORT_OPENGL |
                                          PFD_DOUBLEBUFFER,
                                          PFD_TYPE_RGBA,
                                          32,
                                          0, 0, 0, 0, 0, 0,
                                          0,
                                          0,
                                          0,
                                          0, 0, 0, 0,
                                          16,
                                          0,
                                          0,
                                          PFD_MAIN_PLANE,
                                          0,
                                          0, 0, 0 };

     // Choose best matching pixel format, return index
     nPixelFormat = ChoosePixelFormat(hDC, &pfd);
     
     // Set Pixel Format to Device Context
     SetPixelFormat(hDC, nPixelFormat, &pfd);
}

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
        static HGLRC hRC;                         // rendering context
        static HDC   hDC;                         // device context
                
        switch(message)
        {
                       case WM_CREATE:
                            
                            hDC = GetDC(hWnd);            // get current window's device context
                            g_hDC = hDC;                  // set global device context to current
                            SetupPixelFormat(hDC);        // call pixel format setup function
                            
                            hRC = wglCreateContext(hDC);  // create rendering context
                            g_hRC = hRC;
                            wglMakeCurrent(hDC, hRC);     // make it current
                            
                            return 0;
                            break;
                            
                       case WM_CLOSE:
                            
                            // deselect rendering context and delete it
                            wglMakeCurrent(hDC, NULL);
                            wglDeleteContext(hRC);
                            
                            PostQuitMessage(0);
                            
                            return 0;
                            break;
                            
                       case WM_SIZE:
                            
                            ResizeGLScene(LOWORD(lParam),HIWORD(lParam));
                            
                            return 0;
                            break;
                            
                       default:
                               break;
        }
        
        return (DefWindowProc(hWnd, message, wParam, lParam));    //All unhandled messages
        
}


// Main App Entry
int WINAPI WinMain(     HINSTANCE     hInstance,
                        HINSTANCE     hPrevInstance,
                        LPSTR         lpCmdLine,
                        int           nCmdShow)
{
                   WNDCLASSEX windowClass;                        // Window Class
                   char       lpszClassName[] = "MyClass";        // window class name
                   HWND       hWnd;                               // Window handle
                   MSG        msg;                                // message
                   bool       done = FALSE;                         // flag saying when the app is complete
                   
                   windowClass.cbSize             = sizeof(WNDCLASSEX);
                   windowClass.style              = CS_HREDRAW | CS_VREDRAW;
                   windowClass.lpfnWndProc        = WndProc;
                   windowClass.cbClsExtra         = 0;
                   windowClass.cbWndExtra         = 0;
                   windowClass.hInstance          = hInstance;
                   windowClass.hIcon              = LoadIcon(NULL, IDI_APPLICATION);
                   windowClass.hCursor            = LoadCursor(NULL, IDC_ARROW);
                   windowClass.hbrBackground      = NULL;
                   windowClass.lpszMenuName       = NULL;
                   windowClass.lpszClassName      = lpszClassName;
                   windowClass.hIconSm            = LoadIcon(NULL, IDI_WINLOGO);
                   
                   
                   // Register Window Class
                   if(!RegisterClassEx(&windowClass))
                   {
                             MessageBox(NULL,"ERROR: Could not register window class!", "ERROR",MB_OK|MB_ICONEXCLAMATION);
                             return 0;
                   }
                   
                   // Create Window
                   if(!(hWnd = CreateWindowEx(NULL,                    // Extended style
                                         lpszClassName,           // Class Name
                                         "Default OpenGL Window App",     // App name
                                         WS_OVERLAPPEDWINDOW |    // Window style Flags
                                         WS_VISIBLE |
                                         WS_SYSMENU |
                                         WS_CLIPCHILDREN |
                                         WS_CLIPSIBLINGS,
                                         100, 100,                // X,Y Coordinates
                                         400, 400,                // Window Width, Height
                                         NULL,                    // handle to parent
                                         NULL,                    // handle to menu
                                         hInstance,               // application instance
                                         NULL)))                   // no extra params
                   {
                            MessageBox(NULL,"ERROR: Window could not be created!","ERROR",MB_OK|MB_ICONEXCLAMATION);
                            return 0;
                   }
                   
                   ShowWindow(hWnd, SW_SHOW);
                   UpdateWindow(hWnd);                 
                   
                   // Main message loop
                   done = FALSE;
                   
                   while(!done)
                   {
                               PeekMessage(&msg, hWnd, NULL, NULL, PM_REMOVE);
                               
                               if(msg.message == WM_QUIT)    // Receive a quit meesage?
                               {
                                              done = TRUE;
                               }
                               else
                               {    
                                   // do rendering here //
                                   
                                   RenderGLScene();
                               
                                   TranslateMessage(&msg);   // translatte and dispatch to event queue
                                   DispatchMessage(&msg);
                               }
                   }
                   
     return msg.wParam;
}
[/SOURCE]

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sorry for posting again... i might as well go to the top of the list while saying what i think the problem is. I think its either the swapbuffers or rendering function... lol pretty obvious... but i get no errors


EDIT:: Nevermind the problem! I fixed it... it was the if(height == 0)... i had if(height = 0)... woops

[Edited by - GL_aLpHa on June 9, 2006 11:15:33 PM]

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