I am following an example to create a sky box. In my main class, i am creating the window and performing some actions. I have followed what the example does and this is it
#include "stdafx.h"
#include <GL/glut.h>
#include <windows.h>
#include <stdio.h> //for file access
#include <gl\gl.h>
#include "skybox.h"
#include "glbmp.h"
#include "coursework2.h"
#include "3dsloader.h"
#include "texture.h"
//Instance variables
HDC hDC=NULL;
HGLRC hRC=NULL;
HWND hWnd=NULL;
HINSTANCE hInstance;
MSG msg;
//get and instance of the skybox
skybox aSkyBox;
long mouse_x, mouse_y, mouse_temp; //keep track of the mouse
bool keys[256];
bool active=TRUE;
bool fullscreen=FALSE;
//callback procedure
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
//Function that is used to resize the Screen
GLvoid ReSizeGLScene(GLsizei width, GLsizei height) {
if (height<=0) { height=1; }
glViewport(0,0,width,height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45.0f,(GLfloat)width/(GLfloat)height,0.1f,100.0f);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}
//Initalize the OpenGL engine
int InitGL(GLvoid) {
glEnable(GL_TEXTURE_2D);
glShadeModel(GL_SMOOTH); //Try GL_FLAT to see the difference
glClearColor(0.0f, 0.0f, 0.0f, 1.0f); //Background colour
glClearDepth(1.0f);
glEnable(GL_DEPTH_TEST); //Enables depth testing
glDepthFunc(GL_LEQUAL); //Specifies how Depth testing is done
glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST); //Affects quality of colour and texture interpolation
glFrontFace (GL_CCW); //Specifies that the front of a face is defined
//in a Counter Clockwise manner
glCullFace(GL_BACK); //Specifies that the back of faces are not shown
//so OpenGL does not need to draw things twice
glEnable(GL_CULL_FACE); //Enables culling of faces
aSkyBox.Init(); //Initalize the Skybox
mouse_x = 0;
mouse_y = 0;
mouse_temp = -5000;
return TRUE;
}
int DrawGLScene(GLvoid) {
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
//this is where stuff is drawn
aSkyBox.draw();
return TRUE;
}
GLvoid KillGLWindow(GLvoid) {
if (fullscreen)
{
ChangeDisplaySettings(NULL,0);
ShowCursor(TRUE);
}
if (hRC)
{
if (!wglMakeCurrent(NULL,NULL))
{
MessageBox(NULL,"Release Of DC And RC Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
}
if (!wglDeleteContext(hRC))
{
MessageBox(NULL,"Release Rendering Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
}
hRC=NULL;
}
if (hDC && !ReleaseDC(hWnd,hDC))
{
MessageBox(NULL,"Release Device Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
hDC=NULL;
}
if (hWnd && !DestroyWindow(hWnd))
{
MessageBox(NULL,"Could Not Release hWnd.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
hWnd=NULL;
}
if (!UnregisterClass("OpenGL",hInstance))
{
MessageBox(NULL,"Could Not Unregister Class.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
hInstance=NULL;
}
}
bool CreateGLWindow(char* title, int width, int height, int bits, bool fullscreenflag) {
GLuint PixelFormat;
WNDCLASS wc;
DWORD dwExStyle;
DWORD dwStyle;
RECT WindowRect;
WindowRect.left=(long)0;
WindowRect.right=(long)width;
WindowRect.top=(long)0;
WindowRect.bottom=(long)height;
fullscreen=fullscreenflag;
hInstance = GetModuleHandle(NULL);
wc.style = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;
wc.lpfnWndProc = (WNDPROC) WndProc;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = hInstance;
wc.hIcon = LoadIcon(NULL, IDI_WINLOGO);
wc.hCursor = LoadCursor(NULL, IDC_ARROW);
wc.hbrBackground = NULL;
wc.lpszMenuName = NULL;
wc.lpszClassName = "OpenGL";
if (!RegisterClass(&wc)) {
MessageBox(NULL,"Failed To Register The Window Class.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE;
}
if (fullscreen) {
DEVMODE dmScreenSettings;
memset(&dmScreenSettings,0,sizeof(dmScreenSettings));
dmScreenSettings.dmSize=sizeof(dmScreenSettings);
dmScreenSettings.dmPelsWidth = width;
dmScreenSettings.dmPelsHeight = height;
dmScreenSettings.dmBitsPerPel = bits;
dmScreenSettings.dmFields=DM_BITSPERPEL|DM_PELSWIDTH|DM_PELSHEIGHT;
if (ChangeDisplaySettings(&dmScreenSettings,CDS_FULLSCREEN)!=DISP_CHANGE_SUCCESSFUL) {
if (MessageBox(NULL,"The Requested Fullscreen Mode Is Not Supported By\nYour Video Card. Use Windowed Mode Instead?","Video Mode",MB_YESNO|MB_ICONEXCLAMATION)==IDYES) {
fullscreen=FALSE;
} else {
MessageBox(NULL,"Program Will Now Close.","ERROR",MB_OK|MB_ICONSTOP);
return FALSE;
}
}
}
if (fullscreen) {
dwExStyle=WS_EX_APPWINDOW;
dwStyle=WS_POPUP;
ShowCursor(FALSE);
} else {
dwExStyle=WS_EX_APPWINDOW | WS_EX_WINDOWEDGE;
dwStyle=WS_OVERLAPPEDWINDOW;
}
AdjustWindowRectEx(&WindowRect, dwStyle, FALSE, dwExStyle);
if (!(hWnd=CreateWindowEx( dwExStyle,
"OpenGL",
title,
dwStyle |
WS_CLIPSIBLINGS |
WS_CLIPCHILDREN,
0, 0,
WindowRect.right-WindowRect.left,
WindowRect.bottom-WindowRect.top,
NULL,
NULL,
hInstance,
NULL))) {
KillGLWindow();
MessageBox(NULL,"Window Creation Error.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE;
}
static PIXELFORMATDESCRIPTOR pfd={
sizeof(PIXELFORMATDESCRIPTOR),
1,
PFD_DRAW_TO_WINDOW |
PFD_SUPPORT_OPENGL |
PFD_DOUBLEBUFFER,
PFD_TYPE_RGBA,
bits,
0, 0, 0, 0, 0, 0,
0,
0,
0,
0, 0, 0, 0,
16,
0,
0,
PFD_MAIN_PLANE,
0,
0, 0, 0
};
if (!(hDC=GetDC(hWnd))) {
KillGLWindow();
MessageBox(NULL,"Can't Create A GL Device Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE;
}
if (!(PixelFormat=ChoosePixelFormat(hDC,&pfd))) {
KillGLWindow();
MessageBox(NULL,"Can't Find A Suitable PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE;
}
if(!SetPixelFormat(hDC,PixelFormat,&pfd)) {
KillGLWindow();
MessageBox(NULL,"Can't Set The PixelFormat.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE;
}
if (!(hRC=wglCreateContext(hDC))) {
KillGLWindow();
MessageBox(NULL,"Can't Create A GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE;
}
if(!wglMakeCurrent(hDC,hRC)) {
KillGLWindow();
MessageBox(NULL,"Can't Activate The GL Rendering Context.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE;
}
ShowWindow(hWnd,SW_SHOW);
SetForegroundWindow(hWnd);
SetFocus(hWnd);
ReSizeGLScene(width, height);
if (!InitGL()) {
KillGLWindow();
MessageBox(NULL,"Initialization Failed.","ERROR",MB_OK|MB_ICONEXCLAMATION);
return FALSE;
}
return TRUE;
}
LRESULT CALLBACK WndProc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
switch (uMsg) {
case WM_ACTIVATE: {
if (!HIWORD(wParam)) {
active=TRUE;
} else {
active=FALSE;
}
return 0;
}
case WM_SYSCOMMAND: {
switch (wParam) {
case SC_SCREENSAVE:
case SC_MONITORPOWER:
return 0;
}
break;
}
case WM_CLOSE: {
PostQuitMessage(0);
return 0;
}
case WM_MOUSEMOVE: {
if(mouse_temp == -5000) {
mouse_y = HIWORD(lParam);
mouse_x = LOWORD(lParam);
mouse_temp = 0;
} else {
mouse_temp = HIWORD(lParam);
if(mouse_temp > mouse_y) {
aSkyBox.rot_x += (mouse_temp - mouse_y);
}
if(mouse_temp < mouse_y) {
aSkyBox.rot_x -= (mouse_y - mouse_temp);
}
mouse_y = mouse_temp;
mouse_temp = LOWORD(lParam);
if(mouse_temp > mouse_x) {
aSkyBox.rot_y += (mouse_temp - mouse_x);
}
if(mouse_temp < mouse_x) {
aSkyBox.rot_y -= (mouse_x - mouse_temp);
}
mouse_x = mouse_temp;
}
return 0;
}
case WM_KEYDOWN: {
keys[wParam] = TRUE;
return 0;
}
case WM_KEYUP: {
keys[wParam] = FALSE;
return 0;
}
case WM_SIZE: {
ReSizeGLScene(LOWORD(lParam),HIWORD(lParam));
return 0;
}
}
return DefWindowProc(hWnd,uMsg,wParam,lParam);
}
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) {
BOOL done=FALSE;
fullscreen=FALSE;
if (!CreateGLWindow("OpenGL Window",800,600,16,fullscreen)) {
return 0;
}
while(!done) {
if (PeekMessage(&msg,NULL,0,0,PM_REMOVE)) {
if (msg.message==WM_QUIT) {
done=TRUE;
} else {
TranslateMessage(&msg);
DispatchMessage(&msg);
}
} else {
if (active) {
if (keys[VK_ESCAPE]) {
done=TRUE;
} else {
DrawGLScene();
SwapBuffers(hDC);
}
}
if (keys[VK_F1]) {
keys[VK_F1]=FALSE;
KillGLWindow();
fullscreen=!fullscreen;
if (!CreateGLWindow("OpenGL Window",800,600,16,fullscreen)) {
return 0;
}
}
//Allow user to change the skybox
if(keys['1']) {
keys['1']=FALSE;
aSkyBox.text_offset = 0;
}
if(keys['2']) {
keys['2']=FALSE;
aSkyBox.text_offset = 6;
}
if(keys['3']) {
keys['3']=FALSE;
aSkyBox.text_offset = 12;
}
if(keys['4']) {
keys['4']=FALSE;
aSkyBox.text_offset = 18;
}
}
}
KillGLWindow();
return (msg.wParam);
}
