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MDIMarchingCubes.cpp

//---------------------------------------------------------------------------

#include <vcl.h>
#pragma hdrstop

#include "MDIMarchingCubes.h"
#include "MDIEdit.h"
#include "MDIFrame.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TMarchingCubesForm *MarchingCubesForm;
//---------------------------------------------------------------------------
__fastcall TMarchingCubesForm::TMarchingCubesForm(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
void __fastcall TMarchingCubesForm::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,
    };
    PixelFormat = ChoosePixelFormat(hdc, &pfd);
    SetPixelFormat(hdc, PixelFormat, &pfd);
}

//---------------------------------------------------------------------
void __fastcall TMarchingCubesForm::FormClose(TObject *Sender, TCloseAction &Action)
{
Action=caFree;
//FrameForm->MarchingCubes->Checked = false;
}
//---------------------------------------------------------------------
void __fastcall TMarchingCubesForm::FormCreate(TObject *Sender)
{
    int i,a;

    hdc = GetDC(Handle);
    SetPixelFormatDescriptor();
    hrc = wglCreateContext(hdc);
    if(hrc == NULL) ShowMessage("Could not create DC!");
    wglMakeCurrent(hdc, hrc);

    w = ClientWidth;
    h = ClientHeight;

    glEnable(GL_DEPTH_TEST);
    glEnable(GL_CULL_FACE);

    glClearColor(0.2f, 0.2f, 0.2f, 1.0f);
    glOrtho (-50.0,50.0,-50.0,50.0,-50.0,50.0);

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glFlush();
    SwapBuffers(hdc);
    FormResize(Sender);
}
//---------------------------------------------------------------------
void __fastcall TMarchingCubesForm::FormResize(TObject *Sender)
{
        PrepareGLWindow();
        PaintGL();
}
//---------------------------------------------------------------------------
void __fastcall TMarchingCubesForm::FormPaint(TObject *Sender)
{
        PaintGL();
}
//---------------------------------------------------------------------------
void __fastcall TMarchingCubesForm::PaintGL()
{
        float i;

        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
        PrepareGLWindow();
        glColor3f(0.6f,0.6f,0.6f);
        glLineWidth(3.0f);
        glBegin(GL_LINE_STRIP);
        glVertex3f(-50,-50,0);
        glVertex3f(50,-50,0);
        glVertex3f(50,50,0);
        glVertex3f(-50,50,0);
        glVertex3f(-50,-50,0);
        glEnd();


//        glDrawPixels(sizeX, sizeY, GL_RGB, GL_UNSIGNED_BYTE,
//                     color+(sizeX*sizeY*TrackBar->Position));
                        // we use unsigned byte (char) to meet speed issues.
                        // 16 bit data (__int16) slows down drawing to much.

        glFlush();
        SwapBuffers(hdc);
}

void __fastcall TMarchingCubesForm::PrepareGLWindow()
{
        wglMakeCurrent(hdc, hrc);

        GLfloat nRange = 50.0;

        w = ClientWidth-200;
        h = ClientHeight;

        if(h == 0) h = 1;
        if(w == 0) w = 1;

        glViewport(200, 0, w, h);

        glMatrixMode(GL_PROJECTION);
        glLoadIdentity();

        if (w <= h)
        {        glOrtho (-nRange, nRange, -nRange*h/w, nRange*h/w, -nRange, nRange);
                glPixelZoom((float)w/(float)sizeX, (float)w/(float)sizeY);}
         else
        {        glOrtho (-nRange*w/h, nRange*w/h, -nRange, nRange, -nRange, nRange);
                glPixelZoom((float)h/(float)sizeX, (float)h/(float)sizeY);}

        glRasterPos2d(-50,-50);
        glMatrixMode(GL_MODELVIEW);
        glLoadIdentity();
}
//---------------------------------------------------------------------------

void __fastcall TMarchingCubesForm::FormActivate(TObject *Sender)
{
        PaintGL();        
}
//---------------------------------------------------------------------------

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