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Im having trouble setting up the coordinate system in my gl window, it seems that my call to glOrtho completely ignores my xmin/xmax and ymin/ymax variables note* that my glwindow.hpp class doesnt call any opengl functions
#include <windows.h>
#include <math.h>
#include "GLWindow.hpp"

const int WIDTH = 800;
const int HEIGHT = 600;

typedef float (*function)(float, float);
typedef void (*normal) (float, float, float, float*);

float f1(float x, float z);
float f2(float x, float z);
void normal1(float x, float y, float z, float* norm);
void normal2(float x, float y, float z, float* norm);

function drawFuncs[2] = {&f1, &f2};
normal normFuncs[2] = {&normal1, &normal2};
int curFIndex = 0;

int drawMethods[3] = {GL_LINE_STRIP, GL_POLYGON, GL_POINTS};
int curDrawIndex = 0;

float theta = 0;
float xmin=-2, xmax=2, ymin=-2,ymax=2,zmin=-2,zmax=2;
int n = 20, m = 20;

void Resize(int w, int h)
{
	//set the viewing area
	glViewport(0, 0, w, h);

	glMatrixMode(GL_PROJECTION);						// Select The Projection Matrix
	glLoadIdentity();									// Reset The Projection Matrix
	glOrtho(xmin, xmax, ymin, ymax, zmin, zmax);
	gluPerspective(45,(GLfloat)w/(GLfloat)h,0.1f,100.0f);

	// Calculate The Aspect Ratio Of The Window
	glMatrixMode(GL_MODELVIEW);							// Select The Modelview Matrix
	glLoadIdentity();
}

void InitGL()
{
	GLfloat mat_specular[] = {0, 1, 0, 0};
	GLfloat mat_diffuse[] = {1, 1, 1, 0};
	GLfloat mat_ambient[] = {1, 1, 1, 0};
	GLfloat shininess[] = {2};
	
	GLfloat light_specular[] = {0, 1, 0, 1};
	GLfloat light_diffuse[] = {1, .9, .9, 0};
	GLfloat light_ambient[] = {.1, .1, .1, 0};
	GLfloat light_position[] = {-20, 4, 0, 0};

	glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
	glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
	glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
	glLightfv(GL_LIGHT0, GL_POSITION, light_position);

	glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
	glMaterialfv(GL_FRONT, GL_AMBIENT, mat_ambient);
	glMaterialfv(GL_FRONT, GL_DIFFUSE, mat_diffuse);
	glMaterialfv(GL_FRONT, GL_SHININESS, shininess);

	glShadeModel(GL_SMOOTH);
	float lmodel_ambient[] = {.4,.4,.4,.4};
	glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);
	glEnable(GL_LIGHTING);
	glEnable(GL_LIGHT0);

	glEnable(GL_DEPTH_TEST);
	glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);

	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	glClearColor(0,0,0,0);
	glColor3f(0,0,0);
}

//function 1
float f1(float x, float z)
{
	return exp(-x*x-z*z);
}


//norm
void normal1(float x, float y, float z, float* norm)
{
	norm[0] = 2*x*exp(-x*x-z*z);
	norm[1] = 1;
	norm[2] = 2*z*exp(-x*x-z*z);
	float d = norm[0]*norm[0]+norm[1]*norm[1]+norm[2]*norm[2];
	if (d>0)
	{
		for (int k = 0; k < 3; k++)
			norm[k]/=d;
	}
}

//function 2
float f2(float x, float z)
{
	return z*cos(x);
}

//norm 2
void normal2(float x, float y, float z, float* norm)
{
	norm[0] = z*sin(x);
	norm[1] = 1;
	norm[2] = -1*cos(x);
	float d = norm[0]*norm[0]+norm[1]*norm[1]+norm[2]*norm[2];
	if (d>0)
	{
		for (int k = 0; k < 3; k++)
			norm[k]/=d;
	}
}

void DisplayFunc()
{
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glRotatef(20,1,0,0);
	glTranslatef(0,0,-1);
	

	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	glRotatef(20,1,0,0);
	glRotatef(theta,0,1,0);

	float norm[3];
	double xgap=(xmax-xmin)/n;
	double zgap=(zmax-zmin)/m;

	//float y = 0;

	for (int i = 0; i < n; i++)
	{
		for (int j = 0; j < m; j++)
		{
			glBegin(drawMethods[curDrawIndex]);
			float x = xmin+i*xgap;
			float z = zmin+j*zgap;
			float y = drawFuncs[curFIndex](x,z);
			glVertex3f(x,y,z);
			normFuncs[curFIndex](x,y,z,norm);
			glNormal3fv(norm);

			 x = xmin+i*xgap;
			 z = zmin+(j+1)*zgap;
			 y = drawFuncs[curFIndex](x,z);
			glVertex3f(x,y,z);
			normFuncs[curFIndex](x,y,z,norm);
			glNormal3fv(norm);

			 x = xmin+(i+1)*xgap;
			 z = zmin+(j+1)*zgap;
			 y = drawFuncs[curFIndex](x,z);
			glVertex3f(x,y,z);
			normFuncs[curFIndex](x,y,z,norm);
			glNormal3fv(norm);
			glEnd();

			glBegin(drawMethods[curDrawIndex]);
			 x = xmin+(i+1)*xgap;
			 z = zmin+j*zgap;
			 y = drawFuncs[curFIndex](x,z);
			glVertex3f(x,y,z);
			normFuncs[curFIndex](x,y,z,norm);
			glNormal3fv(norm);

			 x = xmin+i*xgap;
			 z = zmin+j*zgap;
			 y = drawFuncs[curFIndex](x,z);
			glVertex3f(x,y,z);
			normFuncs[curFIndex](x,y,z,norm);
			glNormal3fv(norm);

			 x = xmin+(i+1)*xgap;
			 z = zmin+(j+1)*zgap;
			 y = drawFuncs[curFIndex](x,z);
			glVertex3f(x,y,z);
			normFuncs[curFIndex](x,y,z,norm);
			glNormal3fv(norm);
			glEnd();
		}
	}
}

void Keyboard(bool* GL_KEYS, bool isDown)
{
	if (GL_KEYS[97])
	{
		m += 5; n+= 5;
	}
	if (GL_KEYS[int('s')])
	{
		m -= 5; n-= 5;
	}
	if (GL_KEYS[int('d')])
	{
		curDrawIndex += 1;
		if (curDrawIndex > 2)
			curDrawIndex = 0;
	}
	if (GL_KEYS[int('f')])
	{
		curFIndex += 1;
		if (curFIndex > 1)
		curFIndex = 0;
	}
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd)
{
	bool ret = false;

	//start the gl window
	GLWindow myWindow("Function Stuff", WIDTH, HEIGHT);
	myWindow.glInitFunc(InitGL);
	myWindow.glResizeFunc(Resize);
	myWindow.glKeyboard(Keyboard);
	myWindow.glDisplayFunc(DisplayFunc);

	//fulscreen?
	if (myWindow.MsgBox("Do You Want To Run Fullscreen?", "Fullscreen", MB_YESNO | MB_ICONQUESTION) == IDNO)
		ret = myWindow.glStart(false, 32);
	else
		ret = myWindow.glStart(true, 32);

	//if the window failed, close the program
	if (!ret)
	{
		myWindow.MsgBox("Failed to start opengl", "Error", MB_OK | MB_ICONEXCLAMATION);
		return -1;
	}

	ShowCursor(TRUE);

	MSG msg = {0};

	//process window messages
	while (WM_QUIT != msg.message)
	{
		while(PeekMessage(&msg, NULL, 0, 0, PM_REMOVE) == TRUE)
		{
			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}

		//wait until all window messages are processed before drawing scene
		myWindow.glDrawScene();

		theta += 0.1;
		if (theta >360)
			theta = 0;
	}

	return (int)msg.wParam;
}

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You are calling both glOrth() and gluPerspective() in your Resize(). glOrtho() is to create a orthographic(parallel) viewing frustum, and gluPerspective() is to create a perspective viewing frustum.

Please comment out gluPerspective() call.

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Ok it is commented out, but i still get the same results.

if you want to try and compiling and testing on your machine here are my window wrapper classes

window.hpp

/***********************************************************************
File: Window.hpp

Copyright (C) 2008 Jacob Bills

//$---------------------------------------------------------------------
A wrapper class for a Window. Can handle Multi-Byte char sets, and
Unicode which is really convienient.

Last Modified: September 29, 2008
Version: v1.0
//*********************************************************************/


#ifndef WINDOW_HPP
#define WINDOW_HPP

#ifndef _WINDOWS_
#include <windows.h>
#endif

#include <string>

/**************************************************************************
Inputs- pointer to a charArray
Outputs- the length of the charArray
**************************************************************************/

int charlen(const char* theCharArray)
{
if (theCharArray == NULL)
return 0;

int x;
for (x = 0; theCharArray[x] != 0; ++x){}
return x;
}

/**************************************************************************
Inputs- pointer to a wideCharArray
Outputs- the length of the wideCharArray
**************************************************************************/

int widelen(const wchar_t* theWideArray)
{
if (theWideArray == NULL)
return 0;

int x;
for (x = 0; theWideArray[x] != 0; ++x){}
return x;
}

/**************************************************************************
Inputs- pointer to a charArray
Outputs- the corresponding wide char array
*note* user is responsible for clearing up memory from this call
**************************************************************************/

wchar_t* ConvertCharToWide(const char* charArray)
{
int len = charlen(charArray)+1;
wchar_t* ret = new wchar_t[len];
MultiByteToWideChar(CP_ACP, NULL, charArray, -1, ret, len);
return ret;
}

/**************************************************************************
Inputs- pointer to a wide char array
Outputs- the corresponding char array
*note* user is responsible for clearing up memory from this call
**************************************************************************/

char* ConvertWideToChar(const wchar_t* wideArray)
{
int len = widelen(wideArray)+1;
char* ret = new char[len];
WideCharToMultiByte(CP_ACP, NULL, wideArray, -1, ret, len, NULL, NULL);
return ret;
}

/**************************************************************************
Inputs- integer
Outputs- the corresponding char array
*note* user is responsible for clearing up memory from this call
**************************************************************************/

char* ConvertIntToChar(int number)
{
char* ch = new char[10];
_itoa_s(number, ch, 10, 10);
return ch;
}

class Window
{
public:
Window();

#ifdef _MBCS
Window(LPCSTR title, int width = 320, int height = 200);
const LPCSTR GetTitle()const;
#endif

#ifdef _UNICODE
Window(const char* title, int width = 320, int height = 200);
const wchar_t* GetTitle()const;
#endif

int MsgBox(const char* message, const char* caption, UINT uType = NULL);
int MsgBox(const int number, const char* caption, UINT uType = NULL);

void SetupWndClass(HICON icon = NULL, HICON smIcon = NULL, HCURSOR cursor = NULL, UINT classStyle = CS_HREDRAW | CS_VREDRAW, int cbsClsExtra = 0, int cbWndExtra = 0, HBRUSH brush = CreateSolidBrush(RGB(240,240,240)), LPCSTR menuName =NULL);

~Window();
const HWND& GetHWND()const;
const HINSTANCE& GetINST()const;

int GetWidth()const {return myWidth;}
int GetHeight()const {return myHeight;}

//these functions should be called before InitWindow
void SetBGColor(int r = 210, int g = 210, int b = 210);
void SetIconBig(HICON icon = NULL);
void SetIconSmall(HICON icon = NULL);
void SetCursor(HCURSOR cursor = NULL);
void SetEnabled(BOOL val = TRUE);
void SetPosition(int x = 0, int y = 0);
void SetMaxButton(BOOL val = true);
void SetMinButton(BOOL val = true);
void SetWidth(int width);
void SetHeight(int height);
void SetStyle(int cStyle = CS_HREDRAW | CS_VREDRAW);
void SetWindowStyle(DWORD style = WS_OVERLAPPEDWINDOW);
void SetWindowExStyle(DWORD style = 0);
void SetVisible(BOOL val = true);

bool InitSimpleWindow(bool fullscreen = false, int bits = 16);
bool InitWindow(bool fullscreen = false, int bits = 16);

char* OpenFileDialog(OPENFILENAME& ofn)const;
char* OpenFileDialog()const;
void DefOpenFileName(OPENFILENAME& ofn)const;

virtual LRESULT WndProc(UINT message, WPARAM wParam, LPARAM lParam);
static LRESULT CALLBACK StaticProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);
protected:
HWND myHwnd;
bool myFullscreen;
int myBits;
private:
void SetDefaults();

DWORD myWinStyle, myWinExStyle;
BOOL maxButton, minButton, winEnabled;
int myWidth, myHeight;

#ifdef _MBCS
LPCSTR title;
#endif

#ifdef _UNICODE
wchar_t* title;
#endif

HINSTANCE myInst;
WNDCLASSEX myWndClass;
};

Window::Window()
{
#ifdef _MBCS
title = NULL;
#endif

#ifdef _UNICODE
title = new wchar_t[2];
title[0] = ' ';
title[1] = '\0';
#endif

myWidth = 320;
myHeight = 200;
SetDefaults();
}

#ifdef _MBCS
Window::Window(LPCSTR title, int width, int height)
{
this->title = title;
if (width != NULL)
myWidth = width;
if (height != NULL)
myHeight = height;
SetDefaults();
}

const LPCSTR Window::GetTitle()const
{
return title;
}
#endif

#ifdef _UNICODE
Window::Window(const char* title, int width, int height)
{
size_t len = strlen(title);
this->title = new wchar_t[len+1];

for (size_t i = 0; i < len; i++)
this->title[i] = title[i];

this->title[len] = '\0';

if (width != NULL)
myWidth = width;
if (height != NULL)
myHeight = height;
SetDefaults();
}

const wchar_t* Window::GetTitle()const
{
return title;
}
#endif

void Window::SetupWndClass(HICON icon, HICON smIcon, HCURSOR cursor, UINT classStyle, int cbsClsExtra, int cbWndExtra, HBRUSH brush, LPCSTR menuName)
{
myWndClass.style = classStyle; //the class style
myWndClass.cbClsExtra = cbsClsExtra; //extra bytes to allocate for this class
myWndClass.cbWndExtra = cbWndExtra; //extra bytes to allocate for this instance
myWndClass.hIcon = icon; //icon to associate with the app
myWndClass.hCursor = cursor; //the default cursor to use
myWndClass.hbrBackground = brush; //the background color

#ifdef _MBCS
myWndClass.lpszMenuName = menuName; //the resource name for the menu
#endif

#ifdef _UNICODE
myWndClass.lpszMenuName = (LPCWSTR)menuName;
#endif

myWndClass.hIconSm = smIcon; //handle to the small icon
}

int Window::MsgBox(const char* message, const char* caption, UINT uType)
{
#ifdef _MBCS
if (caption == NULL)
caption = title;

return MessageBox(myHwnd, message, caption, uType);
#endif

#ifdef _UNICODE
int ret = 0;
wchar_t* msg = ConvertCharToWide(message);
wchar_t* cap = ConvertCharToWide(caption);
if (caption != NULL)
ret = MessageBox(myHwnd, msg, cap, uType);
else
ret = MessageBox(myHwnd, msg, title, uType);

delete [] msg;
delete [] cap;
return ret;
#endif
}

int Window::MsgBox(const int number, const char* caption, UINT uType)
{
char ch[10];
_itoa_s(number, ch, 10, 10);
return MsgBox(ch, caption);
}

Window::~Window()
{
#ifdef _UNICODE
delete [] title;
title = NULL;
#endif

if (myFullscreen)
{
ChangeDisplaySettings(NULL,0);
}
}

bool Window::InitSimpleWindow(bool fullscreen, int bits)
{
//setup a simple wndclass
SetupWndClass(NULL, NULL, NULL, CS_HREDRAW | CS_VREDRAW, 0, 0, CreateSolidBrush(RGB(244,244,244)), NULL);

return InitWindow(fullscreen, bits);
}

bool Window::InitWindow(bool fullscreen, int bits)
{
#ifdef _MBCS
myWndClass.lpszClassName = (LPCSTR)title; //class name being created
#endif

#ifdef _UNICODE
myWndClass.lpszClassName = (LPCWSTR)title;
#endif

RegisterClassEx(&myWndClass);

//Resize the Window
RECT rect = {0, 0, myWidth, myHeight};
AdjustWindowRect(&rect, myWinStyle, FALSE);

if (fullscreen)
{
DEVMODE dmScreenSettings;
memset(&dmScreenSettings, 0, sizeof(dmScreenSettings)); //clear variable
dmScreenSettings.dmSize = sizeof(dmScreenSettings);
dmScreenSettings.dmPelsWidth = myWidth;
dmScreenSettings.dmPelsHeight = myHeight;
dmScreenSettings.dmBitsPerPel = bits;
dmScreenSettings.dmFields = DM_BITSPERPEL | DM_PELSWIDTH | DM_PELSHEIGHT;

if (ChangeDisplaySettings(&dmScreenSettings, CDS_FULLSCREEN) != DISP_CHANGE_SUCCESSFUL)
{
myFullscreen = false;
return false;
}
}

if (!fullscreen)
{
//for placing window in center of screen
RECT cen;
GetWindowRect(GetDesktopWindow(), &cen);

//create the Window from the class above
myHwnd = CreateWindowEx(myWinExStyle, myWndClass.lpszClassName, myWndClass.lpszClassName,
myWinStyle, (cen.right - myWidth) / 2, (cen.bottom - myHeight) / 2,
rect.right - rect.left, rect.bottom - rect.top,
NULL, NULL, this->myInst, this);
}
else
{
//these two styles make it fullscreen
myWinExStyle = WS_EX_APPWINDOW;
myWinStyle = WS_POPUP;

//create the Window from the class above, also is not centered to screen
myHwnd = CreateWindowEx(myWinExStyle, myWndClass.lpszClassName, myWndClass.lpszClassName,
myWinStyle, 0, 0,
rect.right - rect.left, rect.bottom - rect.top,
NULL, NULL, this->myInst, this);
}

if (!myHwnd)
return false;

//display Window on the screen
ShowWindow(myHwnd, SW_SHOW);
UpdateWindow(myHwnd);
myFullscreen = fullscreen;
myBits = bits;

return true;
}

const HWND& Window::GetHWND()const
{
return myHwnd;
}

const HINSTANCE& Window::GetINST()const
{
return myInst;
}

void Window::DefOpenFileName(OPENFILENAME& ofn)const
{
char CurrentDir[MAX_PATH];

#ifdef _MBCS
GetCurrentDirectory( MAX_PATH, CurrentDir );
ofn.lpstrFilter = "All Files\0*.*\0\0";
ofn.lpstrTitle = "Open a file";
ofn.lpstrInitialDir = CurrentDir;
#endif

#ifdef _UNICODE
wchar_t* initDir = ConvertCharToWide(CurrentDir);
GetCurrentDirectory( MAX_PATH, initDir);
ofn.lpstrFilter = L"All Files\0*.*\0\0";
ofn.lpstrTitle = L"Open a file";
ofn.lpstrInitialDir = initDir;
delete [] initDir;
#endif

ofn.lStructSize = sizeof( OPENFILENAME );
ofn.hwndOwner = NULL;
ofn.lpstrCustomFilter = NULL;
ofn.nMaxCustFilter = 0;
ofn.nFilterIndex = 0;
ofn.lpstrFileTitle = NULL;
ofn.nMaxFileTitle = 0;
ofn.nFileOffset = 0;
ofn.nFileExtension = 0;
ofn.lpstrDefExt = NULL;
ofn.lCustData = 0;
ofn.lpfnHook = NULL;
ofn.lpTemplateName = NULL;
ofn.Flags = OFN_EXPLORER | OFN_ALLOWMULTISELECT;
}

char* Window::OpenFileDialog()const
{
OPENFILENAME defOfn;
DefOpenFileName(defOfn);
return OpenFileDialog(defOfn);
}

char* Window::OpenFileDialog(OPENFILENAME& OpenFileName)const
{
#ifdef _MBCS
char szFile[MAX_PATH];
std::string FData("");
#endif

#ifdef _UNICODE
wchar_t szFile[MAX_PATH];
LPWSTR FData;
#endif

szFile[0] = 0;

OpenFileName.lpstrFile = szFile;
OpenFileName.nMaxFile = sizeof( szFile );

if( GetOpenFileName( &OpenFileName ) )
{
#ifdef _MBCS
size_t len = strlen(OpenFileName.lpstrFile);
#endif

#ifdef _UNICODE
char* conv = ConvertWideToChar(szFile);
size_t len = strlen(conv);
#endif

if( OpenFileName.lpstrFile[len + 1] == 0)
{
// If single file was selected.
char* fPath = new char[MAX_PATH];

#ifdef _MBCS
strcpy_s(fPath, MAX_PATH, szFile);
return fPath;
#endif

#ifdef _UNICODE
strcpy_s(fPath, MAX_PATH, conv);
delete [] conv;
return fPath;
#endif
}
else
{
#ifdef _UNICODE
std::string theStr("");
#endif

FData = OpenFileName.lpstrFile;

#ifdef _UNICODE
char* temp = ConvertWideToChar(FData);
theStr = theStr + temp;
delete [] temp;
#endif

OpenFileName.lpstrFile += len + 1;

while(OpenFileName.lpstrFile[0])
{
#ifdef _MBCS
//This will contain the current file name from multiple selection.
FData = FData + "|" + OpenFileName.lpstrFile;

//find next name
len = strlen(OpenFileName.lpstrFile);
#endif

#ifdef _UNICODE
char* temp = ConvertWideToChar(OpenFileName.lpstrFile);
theStr = theStr + "|" + temp;
len = strlen(temp);
delete [] temp;
#endif

OpenFileName.lpstrFile += len + 1;
}

#ifdef _MBCS
char* ret = new char[FData.length() + 1];
strcpy_s(ret, FData.length() + 2, FData.c_str());
ret[FData.length()] = '\0';
#endif

#ifdef _UNICODE
char* ret = new char[theStr.length() + 1];
strcpy_s(ret, theStr.length() + 2, theStr.c_str());
ret[theStr.length()] = '\0';
#endif

return ret;
}
}
return NULL;
}

void Window::SetDefaults()
{
myInst = NULL;
myHwnd = NULL;
SetBGColor();
SetEnabled();
SetMaxButton();
SetMinButton();
SetStyle();
SetWindowStyle();
SetWindowExStyle();
SetupWndClass();
myWndClass.hInstance = myInst;
myWndClass.cbSize = sizeof(WNDCLASSEX);
myWndClass.lpfnWndProc = (WNDPROC)StaticProc;
myFullscreen = false;
}

void Window::SetBGColor(int r, int g, int b)
{
myWndClass.hbrBackground = CreateSolidBrush(RGB(r,g,b));
}

void Window::SetIconBig(HICON icon)
{
myWndClass.hIcon = icon;
}

void Window::SetIconSmall(HICON icon)
{
myWndClass.hIconSm = icon;
}

void Window::SetCursor(HCURSOR cursor)
{
myWndClass.hCursor = cursor;
}

void Window::SetEnabled(BOOL val)
{
winEnabled = val;
EnableWindow(myHwnd, val);
}

void Window::SetPosition(int x, int y)
{
MoveWindow(myHwnd, x, y, myWidth, myHeight, true);
}

void Window::SetMaxButton(BOOL val)
{
maxButton = val;
}

void Window::SetMinButton(BOOL val)
{
minButton = val;
}

void Window::SetWidth(int width)
{
}

void Window::SetHeight(int height)
{
}

void Window::SetStyle(int cStyle)
{
myWndClass.style = cStyle;
}

void Window::SetWindowStyle(DWORD style)
{
myWinStyle = style;
}

void Window::SetWindowExStyle(DWORD style)
{
myWinExStyle = style;
}

void Window::SetVisible(BOOL val)
{
ShowWindow(myHwnd, val);
}

LRESULT CALLBACK Window::StaticProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
Window* pParent;

// Get pointer to window
if(message == WM_CREATE)
{
pParent = (Window*)((LPCREATESTRUCT)lParam)->lpCreateParams;
//shouldnt be used in 64bit programs??? (__int3264) added to get rid of warning
SetWindowLongPtr(hWnd,GWL_USERDATA,(__int3264)(LONG_PTR)pParent);
}
else
{
pParent = (Window*)GetWindowLongPtr(hWnd,GWL_USERDATA);
if(!pParent) return DefWindowProc(hWnd,message,wParam,lParam);
}

//Call the non-static window proc
pParent->myHwnd = hWnd;
return pParent->WndProc(message,wParam,lParam);
}

LRESULT Window::WndProc(UINT message, WPARAM wParam, LPARAM lParam)
{
//check any available messages from the queue
switch (message)
{
case WM_KEYDOWN:
switch(wParam)
{
//check if user hit escape key
case VK_ESCAPE: PostQuitMessage(0);
break;
}
break;

//the user hit the close button
case WM_DESTROY:
PostQuitMessage(0);
break;
}

return DefWindowProc(myHwnd, message, wParam, lParam);
}

#endif



and glwindow.hpp

/***********************************************************************
File: GLWindow.hpp

Copyright (C) 2008 Jacob Bills

//$---------------------------------------------------------------------
This class helps create a window for rendering graphics using the
opengl library. It is an extension of the Window class and can
run in fullscreen and windowed mode

Last Modified: September 29, 2008
Version: v1.0
//*********************************************************************/


#ifndef GL_WINDOW
#define GL_WINDOW

#include "window.hpp"
#include <glut.h>

typedef void (*VOIDFUNC)();
typedef void (*IIFUNC)(int,int);
typedef void (*KFUNC)(bool*, bool);

class GLWindow : public Window
{
public:
GLWindow(const char* title, int width, int height, bool fullscreen = false, int bits = 16);
~GLWindow();

//gl functions setup
void glDisplayFunc(VOIDFUNC ptrFunction) {myDraw = ptrFunction;}
void glInitFunc(VOIDFUNC ptrFunction) {myInit = ptrFunction;}
void glResizeFunc(IIFUNC ptrFunction) {myResize = ptrFunction;}
void glMouseFunc(IIFUNC ptrFunction) {myMouse = ptrFunction;}
void glKeyboard(KFUNC ptrFunction) {myKeyboard = ptrFunction;}

//gl action functions
void glShowCursor(bool show) {ShowCursor(show);}
void glDrawScene() {myDraw(); SwapBuffers(dc);}

//starts the gl window, sets pixel format
bool glStart(bool fullscreen = false, int bits = 16);

//the window procedure function
virtual LRESULT WndProc(UINT message, WPARAM wParam, LPARAM lParam);
private:
//functions
VOIDFUNC myInit;
VOIDFUNC myDraw;
IIFUNC myResize;
IIFUNC myMouse;
KFUNC myKeyboard;

HGLRC hRC;
HDC dc;

bool GL_KEYS[256];

int width, height;
};

GLWindow::GLWindow(const char* title, int width, int height, bool fullscreen, int bits):Window(title, width, height)
{
this->width = width;
this->height = height;
myInit = NULL;
myDraw = NULL;
myResize = NULL;
myMouse = NULL;
myKeyboard = NULL;

for (int i = 0; i < 256; i++)
GL_KEYS[i] = false;
}

GLWindow::~GLWindow()
{
//release rendering context
wglMakeCurrent(NULL,NULL);

//delete context
wglDeleteContext(hRC);

//release our dc
ReleaseDC(myHwnd, dc);

//show cursor
ShowCursor(TRUE);
}

bool GLWindow::glStart(bool fullscreen, int bits)
{
GLuint PixelFormat;

if (myInit == NULL || myResize == NULL)
{
this->MsgBox("You havnt setup the GLWindow class properly yet, make sure you check that your functions passed to the GLWindow class", "Faield to Start GLWindow", MB_OK | MB_ICONEXCLAMATION);
return false;
}

bool ret = Window::InitWindow(fullscreen, bits);

if (!ret)
return false;

static PIXELFORMATDESCRIPTOR pfd= // pfd Tells Windows How We Want Things To Be
{
sizeof(PIXELFORMATDESCRIPTOR), // Size Of This Pixel Format Descriptor
1, // Version Number
PFD_DRAW_TO_WINDOW | // Format Must Support Window
PFD_SUPPORT_OPENGL | // Format Must Support OpenGL
PFD_DOUBLEBUFFER, // Must Support Double Buffering
PFD_TYPE_RGBA, // Request An RGBA Format
bits, // Select Our Color Depth
0, 0, 0, 0, 0, 0, // Color Bits Ignored
0, // No Alpha Buffer
0, // Shift Bit Ignored
0, // No Accumulation Buffer
0, 0, 0, 0, // Accumulation Bits Ignored
16, // 16Bit Z-Buffer (Depth Buffer)
0, // No Stencil Buffer
0, // No Auxiliary Buffer
PFD_MAIN_PLANE, // Main Drawing Layer
0, // Reserved
0, 0, 0 // Layer Masks Ignored
};

dc = GetDC(myHwnd);

if (!dc)
{
MsgBox("Failed to get dc of window", "Error", MB_OK | MB_ICONEXCLAMATION);
return false;
}

if (!(PixelFormat = ChoosePixelFormat(dc, &pfd)))
{
MsgBox("Failed to get pixel format", "Error", MB_OK | MB_ICONEXCLAMATION);
return false;
}

if(!SetPixelFormat(dc,PixelFormat,&pfd))
{
MsgBox("Failed to set pixel format", "Error", MB_OK | MB_ICONEXCLAMATION);
return false;
}

//create rendering context
if (!(hRC=wglCreateContext(dc)))
{
MsgBox("Failed to create rendering context", "Error", MB_OK | MB_ICONEXCLAMATION);
return false;
}

if(!wglMakeCurrent(dc,hRC))
{
MsgBox("Failed to apply rendering context", "Error", MB_OK | MB_ICONEXCLAMATION);
return false;
}

ShowCursor(FALSE);

//init gl
myInit();
myResize(width, height);

return true;
}

LRESULT GLWindow::WndProc(UINT message, WPARAM wParam, LPARAM lParam)
{
//check any available messages from the queue
switch (message)
{
case WM_MOUSEMOVE:
if (myMouse != NULL)
myMouse(LOWORD(lParam), HIWORD(lParam));
break;
case WM_KEYDOWN:
switch(wParam)
{
//check if user hit escape key
case VK_ESCAPE: PostQuitMessage(0); break;
default:
if (wParam == VK_SHIFT)
GL_KEYS[wParam] = true;

if (wParam >=65 && wParam <= 90)
{
if (GL_KEYS[VK_SHIFT] == true)
GL_KEYS[wParam] = true;
else
GL_KEYS[wParam+32] = true;
}
else if (wParam >= 48 && wParam <= 57)
{
if (GL_KEYS[VK_SHIFT] == true)
{
if (wParam == 49) {GL_KEYS[33] = true;}
if (wParam == 50) {GL_KEYS[64] = true;}
if (wParam == 51) {GL_KEYS[35] = true;}
if (wParam == 52) {GL_KEYS[36] = true;}
if (wParam == 53) {GL_KEYS[37] = true;}
if (wParam == 54) {GL_KEYS[94] = true;}
if (wParam == 55) {GL_KEYS[38] = true;}
if (wParam == 56) {GL_KEYS[42] = true;}
if (wParam == 57) {GL_KEYS[40] = true;}
if (wParam == 48) {GL_KEYS[41] = true;}
}
else
GL_KEYS[wParam] = true;
}
else
GL_KEYS[wParam] = true;

if (myKeyboard != NULL)
{
if ( (lParam >> 15) > 32000)
myKeyboard(GL_KEYS, true);
else
myKeyboard(GL_KEYS, false);
}

break;
}
break;

case WM_KEYUP:
if (wParam == VK_SHIFT)
GL_KEYS[wParam] = true;

if (wParam >=65 && wParam <= 90)
{
if (GL_KEYS[VK_SHIFT] == true)
GL_KEYS[wParam] = false;
else
GL_KEYS[wParam+32] = false;
}
else if (wParam >= 48 && wParam <= 57)
{
if (GL_KEYS[VK_SHIFT] == true)
{
if (wParam == 49) {GL_KEYS[33] = false;}
if (wParam == 50) {GL_KEYS[64] = false;}
if (wParam == 51) {GL_KEYS[35] = false;}
if (wParam == 52) {GL_KEYS[36] = false;}
if (wParam == 53) {GL_KEYS[37] = false;}
if (wParam == 54) {GL_KEYS[94] = false;}
if (wParam == 55) {GL_KEYS[38] = false;}
if (wParam == 56) {GL_KEYS[42] = false;}
if (wParam == 57) {GL_KEYS[40] = false;}
if (wParam == 48) {GL_KEYS[41] = false;}
}
else
GL_KEYS[wParam] = false;
}
else
GL_KEYS[wParam] = false;

if (wParam == VK_SHIFT && GL_KEYS[VK_SHIFT])
GL_KEYS[VK_SHIFT] = false;

if (myKeyboard != NULL)
myKeyboard(GL_KEYS, false);

break;

case WM_SIZE:
if (myResize != NULL)
myResize(LOWORD(lParam), HIWORD(lParam));

break;

//the user hit the close button
case WM_DESTROY:
PostQuitMessage(0);
break;
}

return DefWindowProc(myHwnd, message, wParam, lParam);
}

#endif



please keep in mind my wrapper classes are still not perfect and havnt been optimized.

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That's because you are resetting the projection matrix in the display function:

glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glRotatef(20,1,0,0);
glTranslatef(0,0,-1);


Keep in mind that OpenGL is a state machine, i you change state it will stick globally until you change it again. Typically you should set the projection matrix only on program init, and screen resize, unless you need multiple different projections for single frame (lets say 3d perspective scene with overlay 2D ortho HUD). Keep all your camera and scene movements (rotate,translate,..) to modelview matrix.

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thank you! it worked after i got rid of glPerspective, and
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glRotatef(20,1,0,0);
glTranslatef(0,0,-1);

much appreciation!

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      When sampling a texture in a shader, the texture sampler was traditionally specified as separate object that was bound to the pipeline at run time or set as part of the texture object itself. However, in most cases it is known beforehand what kind of sampler will be used in the shader. Next-generation APIs expose new type of sampler called static sampler that can be initialized directly in the pipeline state. Diligent Engine exposes this functionality: when creating a shader, textures can be assigned static samplers. If static sampler is assigned, it will always be used instead of the one initialized in the texture shader resource view. To initialize static samplers, prepare an array of StaticSamplerDesc structures and initialize StaticSamplers and NumStaticSamplers members. Static samplers are more efficient and it is highly recommended to use them whenever possible. On older APIs, static samplers are emulated via generic sampler objects.
      The following is an example of shader initialization:
      ShaderCreationAttribs Attrs; Attrs.Desc.Name = "MyPixelShader"; Attrs.FilePath = "MyShaderFile.fx"; Attrs.SearchDirectories = "shaders;shaders\\inc;"; Attrs.EntryPoint = "MyPixelShader"; Attrs.Desc.ShaderType = SHADER_TYPE_PIXEL; Attrs.SourceLanguage = SHADER_SOURCE_LANGUAGE_HLSL; BasicShaderSourceStreamFactory BasicSSSFactory(Attrs.SearchDirectories); Attrs.pShaderSourceStreamFactory = &BasicSSSFactory; ShaderVariableDesc ShaderVars[] = {     {"g_StaticTexture", SHADER_VARIABLE_TYPE_STATIC},     {"g_MutableTexture", SHADER_VARIABLE_TYPE_MUTABLE},     {"g_DynamicTexture", SHADER_VARIABLE_TYPE_DYNAMIC} }; Attrs.Desc.VariableDesc = ShaderVars; Attrs.Desc.NumVariables = _countof(ShaderVars); Attrs.Desc.DefaultVariableType = SHADER_VARIABLE_TYPE_STATIC; StaticSamplerDesc StaticSampler; StaticSampler.Desc.MinFilter = FILTER_TYPE_LINEAR; StaticSampler.Desc.MagFilter = FILTER_TYPE_LINEAR; StaticSampler.Desc.MipFilter = FILTER_TYPE_LINEAR; StaticSampler.TextureName = "g_MutableTexture"; Attrs.Desc.NumStaticSamplers = 1; Attrs.Desc.StaticSamplers = &StaticSampler; ShaderMacroHelper Macros; Macros.AddShaderMacro("USE_SHADOWS", 1); Macros.AddShaderMacro("NUM_SHADOW_SAMPLES", 4); Macros.Finalize(); Attrs.Macros = Macros; RefCntAutoPtr<IShader> pShader; m_pDevice->CreateShader( Attrs, &pShader );
      Creating the Pipeline State Object
      After all required shaders are created, the rest of the fields of the PipelineStateDesc structure provide depth-stencil, rasterizer, and blend state descriptions, the number and format of render targets, input layout format, etc. For instance, rasterizer state can be described as follows:
      PipelineStateDesc PSODesc; RasterizerStateDesc &RasterizerDesc = PSODesc.GraphicsPipeline.RasterizerDesc; RasterizerDesc.FillMode = FILL_MODE_SOLID; RasterizerDesc.CullMode = CULL_MODE_NONE; RasterizerDesc.FrontCounterClockwise = True; RasterizerDesc.ScissorEnable = True; RasterizerDesc.AntialiasedLineEnable = False; Depth-stencil and blend states are defined in a similar fashion.
      Another important thing that pipeline state object encompasses is the input layout description that defines how inputs to the vertex shader, which is the very first shader stage, should be read from the memory. Input layout may define several vertex streams that contain values of different formats and sizes:
      // Define input layout InputLayoutDesc &Layout = PSODesc.GraphicsPipeline.InputLayout; LayoutElement TextLayoutElems[] = {     LayoutElement( 0, 0, 3, VT_FLOAT32, False ),     LayoutElement( 1, 0, 4, VT_UINT8, True ),     LayoutElement( 2, 0, 2, VT_FLOAT32, False ), }; Layout.LayoutElements = TextLayoutElems; Layout.NumElements = _countof( TextLayoutElems ); Finally, pipeline state defines primitive topology type. When all required members are initialized, a pipeline state object can be created by IRenderDevice::CreatePipelineState() method:
      // Define shader and primitive topology PSODesc.GraphicsPipeline.PrimitiveTopologyType = PRIMITIVE_TOPOLOGY_TYPE_TRIANGLE; PSODesc.GraphicsPipeline.pVS = pVertexShader; PSODesc.GraphicsPipeline.pPS = pPixelShader; PSODesc.Name = "My pipeline state"; m_pDev->CreatePipelineState(PSODesc, &m_pPSO); When PSO object is bound to the pipeline, the engine invokes all API-specific commands to set all states specified by the object. In case of Direct3D12 this maps directly to setting the D3D12 PSO object. In case of Direct3D11, this involves setting individual state objects (such as rasterizer and blend states), shaders, input layout etc. In case of OpenGL, this requires a number of fine-grain state tweaking calls. Diligent Engine keeps track of currently bound states and only calls functions to update these states that have actually changed.
      Binding Shader Resources
      Direct3D11 and OpenGL utilize fine-grain resource binding models, where an application binds individual buffers and textures to certain shader or program resource binding slots. Direct3D12 uses a very different approach, where resource descriptors are grouped into tables, and an application can bind all resources in the table at once by setting the table in the command list. Resource binding model in Diligent Engine is designed to leverage this new method. It introduces a new object called shader resource binding that encapsulates all resource bindings required for all shaders in a certain pipeline state. It also introduces the classification of shader variables based on the frequency of expected change that helps the engine group them into tables under the hood:
      Static variables (SHADER_VARIABLE_TYPE_STATIC) are variables that are expected to be set only once. They may not be changed once a resource is bound to the variable. Such variables are intended to hold global constants such as camera attributes or global light attributes constant buffers. Mutable variables (SHADER_VARIABLE_TYPE_MUTABLE) define resources that are expected to change on a per-material frequency. Examples may include diffuse textures, normal maps etc. Dynamic variables (SHADER_VARIABLE_TYPE_DYNAMIC) are expected to change frequently and randomly. Shader variable type must be specified during shader creation by populating an array of ShaderVariableDesc structures and initializing ShaderCreationAttribs::Desc::VariableDesc and ShaderCreationAttribs::Desc::NumVariables members (see example of shader creation above).
      Static variables cannot be changed once a resource is bound to the variable. They are bound directly to the shader object. For instance, a shadow map texture is not expected to change after it is created, so it can be bound directly to the shader:
      PixelShader->GetShaderVariable( "g_tex2DShadowMap" )->Set( pShadowMapSRV ); Mutable and dynamic variables are bound via a new Shader Resource Binding object (SRB) that is created by the pipeline state (IPipelineState::CreateShaderResourceBinding()):
      m_pPSO->CreateShaderResourceBinding(&m_pSRB); Note that an SRB is only compatible with the pipeline state it was created from. SRB object inherits all static bindings from shaders in the pipeline, but is not allowed to change them.
      Mutable resources can only be set once for every instance of a shader resource binding. Such resources are intended to define specific material properties. For instance, a diffuse texture for a specific material is not expected to change once the material is defined and can be set right after the SRB object has been created:
      m_pSRB->GetVariable(SHADER_TYPE_PIXEL, "tex2DDiffuse")->Set(pDiffuseTexSRV); In some cases it is necessary to bind a new resource to a variable every time a draw command is invoked. Such variables should be labeled as dynamic, which will allow setting them multiple times through the same SRB object:
      m_pSRB->GetVariable(SHADER_TYPE_VERTEX, "cbRandomAttribs")->Set(pRandomAttrsCB); Under the hood, the engine pre-allocates descriptor tables for static and mutable resources when an SRB objcet is created. Space for dynamic resources is dynamically allocated at run time. Static and mutable resources are thus more efficient and should be used whenever possible.
      As you can see, Diligent Engine does not expose low-level details of how resources are bound to shader variables. One reason for this is that these details are very different for various APIs. The other reason is that using low-level binding methods is extremely error-prone: it is very easy to forget to bind some resource, or bind incorrect resource such as bind a buffer to the variable that is in fact a texture, especially during shader development when everything changes fast. Diligent Engine instead relies on shader reflection system to automatically query the list of all shader variables. Grouping variables based on three types mentioned above allows the engine to create optimized layout and take heavy lifting of matching resources to API-specific resource location, register or descriptor in the table.
      This post gives more details about the resource binding model in Diligent Engine.
      Setting the Pipeline State and Committing Shader Resources
      Before any draw or compute command can be invoked, the pipeline state needs to be bound to the context:
      m_pContext->SetPipelineState(m_pPSO); Under the hood, the engine sets the internal PSO object in the command list or calls all the required native API functions to properly configure all pipeline stages.
      The next step is to bind all required shader resources to the GPU pipeline, which is accomplished by IDeviceContext::CommitShaderResources() method:
      m_pContext->CommitShaderResources(m_pSRB, COMMIT_SHADER_RESOURCES_FLAG_TRANSITION_RESOURCES); The method takes a pointer to the shader resource binding object and makes all resources the object holds available for the shaders. In the case of D3D12, this only requires setting appropriate descriptor tables in the command list. For older APIs, this typically requires setting all resources individually.
      Next-generation APIs require the application to track the state of every resource and explicitly inform the system about all state transitions. For instance, if a texture was used as render target before, while the next draw command is going to use it as shader resource, a transition barrier needs to be executed. Diligent Engine does the heavy lifting of state tracking.  When CommitShaderResources() method is called with COMMIT_SHADER_RESOURCES_FLAG_TRANSITION_RESOURCES flag, the engine commits and transitions resources to correct states at the same time. Note that transitioning resources does introduce some overhead. The engine tracks state of every resource and it will not issue the barrier if the state is already correct. But checking resource state is an overhead that can sometimes be avoided. The engine provides IDeviceContext::TransitionShaderResources() method that only transitions resources:
      m_pContext->TransitionShaderResources(m_pPSO, m_pSRB); In some scenarios it is more efficient to transition resources once and then only commit them.
      Invoking Draw Command
      The final step is to set states that are not part of the PSO, such as render targets, vertex and index buffers. Diligent Engine uses Direct3D11-syle API that is translated to other native API calls under the hood:
      ITextureView *pRTVs[] = {m_pRTV}; m_pContext->SetRenderTargets(_countof( pRTVs ), pRTVs, m_pDSV); // Clear render target and depth buffer const float zero[4] = {0, 0, 0, 0}; m_pContext->ClearRenderTarget(nullptr, zero); m_pContext->ClearDepthStencil(nullptr, CLEAR_DEPTH_FLAG, 1.f); // Set vertex and index buffers IBuffer *buffer[] = {m_pVertexBuffer}; Uint32 offsets[] = {0}; Uint32 strides[] = {sizeof(MyVertex)}; m_pContext->SetVertexBuffers(0, 1, buffer, strides, offsets, SET_VERTEX_BUFFERS_FLAG_RESET); m_pContext->SetIndexBuffer(m_pIndexBuffer, 0); Different native APIs use various set of function to execute draw commands depending on command details (if the command is indexed, instanced or both, what offsets in the source buffers are used etc.). For instance, there are 5 draw commands in Direct3D11 and more than 9 commands in OpenGL with something like glDrawElementsInstancedBaseVertexBaseInstance not uncommon. Diligent Engine hides all details with single IDeviceContext::Draw() method that takes takes DrawAttribs structure as an argument. The structure members define all attributes required to perform the command (primitive topology, number of vertices or indices, if draw call is indexed or not, if draw call is instanced or not, if draw call is indirect or not, etc.). For example:
      DrawAttribs attrs; attrs.IsIndexed = true; attrs.IndexType = VT_UINT16; attrs.NumIndices = 36; attrs.Topology = PRIMITIVE_TOPOLOGY_TRIANGLE_LIST; pContext->Draw(attrs); For compute commands, there is IDeviceContext::DispatchCompute() method that takes DispatchComputeAttribs structure that defines compute grid dimension.
      Source Code
      Full engine source code is available on GitHub and is free to use. The repository contains two samples, asteroids performance benchmark and example Unity project that uses Diligent Engine in native plugin.
      AntTweakBar sample is Diligent Engine’s “Hello World” example.

       
      Atmospheric scattering sample is a more advanced example. It demonstrates how Diligent Engine can be used to implement various rendering tasks: loading textures from files, using complex shaders, rendering to multiple render targets, using compute shaders and unordered access views, etc.

      Asteroids performance benchmark is based on this demo developed by Intel. It renders 50,000 unique textured asteroids and allows comparing performance of Direct3D11 and Direct3D12 implementations. Every asteroid is a combination of one of 1000 unique meshes and one of 10 unique textures.

      Finally, there is an example project that shows how Diligent Engine can be integrated with Unity.

      Future Work
      The engine is under active development. It currently supports Windows desktop, Universal Windows and Android platforms. Direct3D11, Direct3D12, OpenGL/GLES backends are now feature complete. Vulkan backend is coming next, and support for more platforms is planned.
    • By michaeldodis
      I've started building a small library, that can render pie menu GUI in legacy opengl, planning to add some traditional elements of course.
      It's interface is similar to something you'd see in IMGUI. It's written in C.
      Early version of the library
      I'd really love to hear anyone's thoughts on this, any suggestions on what features you'd want to see in a library like this? 
      Thanks in advance!
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