C++ Builder How do I use OpenGL without using GLUT?

Adepted from this article by John Ray Thomas: http://community.borland.com/article/0,1410,10528,00.html

Unit1.hpp:

//---------------------------------------------------------------------------
ifndef Unit1H

define Unit1H

//---------------------------------------------------------------------------
include <Classes.hpp>

include <Controls.hpp>

include <StdCtrls.hpp>

include <Forms.hpp>

include <gl/gl.h>

include <gl/glu.h>

include <math>

//---------------------------------------------------------------------------
class TForm1 : public TForm
{
__published:	// IDE-managed Components
  void __fastcall FormCreate(TObject *Sender);
  void __fastcall FormDestroy(TObject *Sender);
  void __fastcall FormResize(TObject *Sender);
private:	// User declarations
    HDC hdc;
    HGLRC hrc;
    int PixelFormat;
    double angle;
public:		// User declarations
  __fastcall TForm1(TComponent* Owner);
    void __fastcall IdleLoop(TObject*, bool&);
    void __fastcall RenderGLScene();
    void __fastcall SetPixelFormatDescriptor();
    void __fastcall SetupRC();
};
//---------------------------------------------------------------------------
extern PACKAGE TForm1 *Form1;
//---------------------------------------------------------------------------
endif

//Unit1.cpp

//---------------------------------------------------------------------------
include <vcl.h>

pragma hdrstop


include "Unit1.h"

//---------------------------------------------------------------------------
pragma package(smart_init)

pragma resource "*.dfm"

TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
  : TForm(Owner)
{
    Application->OnIdle = IdleLoop;
    angle = 0;
    //_control87(MCW_EM, MCW_EM); //OLD, removed by Richel
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormCreate(TObject *Sender)
{
    hdc = GetDC(Handle);
    SetPixelFormatDescriptor();
    hrc = wglCreateContext(hdc);
    wglMakeCurrent(hdc, hrc);
    SetupRC();
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormDestroy(TObject *Sender)
{
    //ReleaseDC(hdc); //changed by Richel
    ReleaseDC(0, hdc);
    wglMakeCurrent(hdc, NULL);
    wglDeleteContext(hrc);
}
//---------------------------------------------------------------------------
 
void __fastcall TForm1::FormResize(TObject *Sender)
{
    GLfloat nRange = 200.0f;
    glViewport(0, 0, ClientWidth, ClientHeight);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();

    if (ClientWidth <= ClientHeight)
       glOrtho(-nRange, nRange, -nRange*ClientHeight/ClientWidth,
       			nRange*ClientHeight/ClientWidth, -nRange, nRange);
    else
       glOrtho(-nRange*ClientWidth/ClientHeight, nRange*ClientWidth/ClientHeight,
       			-nRange, nRange, -nRange, nRange);
    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
}
//---------------------------------------------------------------------------
void __fastcall TForm1::IdleLoop(TObject*, bool& done)
{
     RenderGLScene();
     SwapBuffers(hdc);
     done = false;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::RenderGLScene()
{
  //Place your OpenGL drawing code here
  //Code below by Richel
  glClear(GL_COLOR_BUFFER_BIT);
  angle+=(M_PI*0.001);
  //glColor3f(1.0,1.0,1.0);
  glColor3f(random(100)/100.0,random(100)/100.0,random(100)/100.0);
  glBegin(GL_POLYGON);
    glVertex3f( 0.0 + (sin(angle+(0.0*M_PI))*125) , 0.5 + (cos(angle+(0.0*M_PI))*125) ,0.0);
    glVertex3f( 0.0 + (sin(angle+(0.5*M_PI))*125) , 0.5 + (cos(angle+(0.5*M_PI))*125) ,0.0);
    glVertex3f( 0.0 + (sin(angle+(1.0*M_PI))*125) , 0.5 + (cos(angle+(1.0*M_PI))*125) ,0.0);
    glVertex3f( 0.0 + (sin(angle+(1.5*M_PI))*125) , 0.5 + (cos(angle+(1.5*M_PI))*125) ,0.0);
  glEnd();
  glFlush();
}
//---------------------------------------------------------------------------
void __fastcall TForm1::SetPixelFormatDescriptor()
{
    PIXELFORMATDESCRIPTOR pfd = {
        sizeof(PIXELFORMATDESCRIPTOR),
        1,
        PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER,
        PFD_TYPE_RGBA,
        24,
        0,0,0,0,0,0,
        0,0,
        0,0,0,0,0,
        32,
        0,
        0,
        PFD_MAIN_PLANE,
        0,
        0,0,0
        };
    PixelFormat = ChoosePixelFormat(hdc, &pfd);
    SetPixelFormat(hdc, PixelFormat, &pfd);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::SetupRC()
{
    glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
    glClear(GL_COLOR_BUFFER_BIT);
    glFlush();
}
//---------------------------------------------------------------------------

Code list

last edited (May 12, 2006) by bilderbikkel, Number of views: 2604, Current Rev: 3 (Diff)

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