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MDIGradient.cpp

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

#include <vcl.h>
#pragma hdrstop

#include "MDIGradient.h"
#include "MDIEdit.h"
#include "MDIFrame.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TGradientForm *GradientForm;
rgb *gradientview;

//---------------------------------------------------------------------------
__fastcall TGradientForm::TGradientForm(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
void __fastcall TGradientForm::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 TGradientForm::FormClose(TObject *Sender, TCloseAction &Action)
{
Action=caFree;
FrameForm->GradientSlices->Checked = false;
delete [] gradientview;
memusage = memusage - 3*512*512;
FrameForm->memupdate();
wglDeleteContext(hrc);
ReleaseDC(Handle,hdc);
}
//---------------------------------------------------------------------
void __fastcall TGradientForm::FormCreate(TObject *Sender)
{
    int i,a;

    gradientview = new rgb[512*512];
    memusage = memusage + 3*512*512;
    FrameForm->memupdate();

    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);
    pagesize = sizeX*sizeY;
        for(int a = 0; a<sizeY; a+=1) {
        for(int i = 0; i<sizeX; i+=1) {
                gradientview[a*sizeX+i].r = gradientview[a*sizeX+i].g = gradientview[a*sizeX+i].b = absgrad[pagesize*TrackBar->Position+a*sizeX+i]/16;
                //StatusProgress->Position = 100*(float(i)/float(size))+1;
        }
        }
    TrackBar->Max = sizeZ-1;
}
//---------------------------------------------------------------------
void __fastcall TGradientForm::FormResize(TObject *Sender)
{
        tPanel->Height = ClientHeight-34;
        TrackBar->Height = ClientHeight-36;
        //kontrast->Height = ClientHeight-188;
        //kontrastpanel->Height = ClientHeight-221;
        PrepareGLWindow();
        PaintGL();
}
//---------------------------------------------------------------------------
void __fastcall TGradientForm::FormPaint(TObject *Sender)
{
        PaintGL();
}
//---------------------------------------------------------------------------
void __fastcall TGradientForm::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.

if (RadioButton1->Checked) glDrawPixels(sizeX, sizeY, GL_RGB, GL_UNSIGNED_BYTE, gradientview);
if (RadioButton2->Checked) glDrawPixels(sizeX, sizeZ, GL_RGB, GL_UNSIGNED_BYTE, gradientview);
if (RadioButton3->Checked) glDrawPixels(sizeY, sizeZ, GL_RGB, GL_UNSIGNED_BYTE, gradientview);

        glFlush();
        SwapBuffers(hdc);
}

void __fastcall TGradientForm::PrepareGLWindow()
{
        wglMakeCurrent(hdc, hrc);
        float yrat;
        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 (RadioButton1->Checked) {
        yrat = (float)sizeX/sizeY;
        if (w <= h*yrat)
        {        glOrtho (-nRange, nRange, -nRange*h*yrat/w, nRange*h*yrat/w, -nRange, nRange);
                glPixelZoom((float)w/(float)sizeX, (float)w/((float)sizeY*yrat));}
         else
        {        glOrtho (-nRange*w/(h*yrat), nRange*w/(h*yrat), -nRange, nRange, -nRange, nRange);
                glPixelZoom((float)h*yrat/(float)sizeX, (float)h/((float)sizeY));}
}
if (RadioButton2->Checked) {
        yrat = (float)sizeX/sizeZ;
        if (w <= h*yrat)
        {        glOrtho (-nRange, nRange, -nRange*h*yrat/w, nRange*h*yrat/w, -nRange, nRange);
                glPixelZoom((float)w/(float)sizeX, (float)w/((float)sizeZ*yrat));}
         else
        {        glOrtho (-nRange*w/(h*yrat), nRange*w/(h*yrat), -nRange, nRange, -nRange, nRange);
                glPixelZoom((float)h*yrat/(float)sizeX, (float)h/(float)sizeZ);}
}
if (RadioButton3->Checked) {
        yrat = (float)sizeY/sizeZ;
        if (w <= h*yrat)
        {        glOrtho (-nRange, nRange, -nRange*h*yrat/w, nRange*h*yrat/w, -nRange, nRange);
                glPixelZoom((float)w/(float)sizeY, (float)w/((float)sizeZ*yrat));}
         else
        {        glOrtho (-nRange*w/(h*yrat), nRange*w/(h*yrat), -nRange, nRange, -nRange, nRange);
                glPixelZoom((float)h*yrat/(float)sizeY, (float)h/(float)sizeZ);}
}

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

void __fastcall TGradientForm::FormActivate(TObject *Sender)
{
        wglMakeCurrent(hdc, hrc);
        PaintGL();
}
//---------------------------------------------------------------------------

void __fastcall TGradientForm::TrackBarChange(TObject *Sender)
{
if (RadioButton1->Checked)
{
        for(int a = 0; a<sizeY; a+=1) {
        for(int i = 0; i<sizeX; i+=1) {
                gradientview[a*sizeX+i].r = gradientview[a*sizeX+i].g = gradientview[a*sizeX+i].b = absgrad[pagesize*TrackBar->Position+a*sizeX+i]/16;
        }
        }
}
if (RadioButton2->Checked)
{
        for(int a = 0; a<sizeZ; a+=1) {
        for(int i = 0; i<sizeX; i+=1) {
                gradientview[a*sizeX+i].r = gradientview[a*sizeX+i].g = gradientview[a*sizeX+i].b = absgrad[pagesize*a+TrackBar->Position*sizeX+i]/16;
        }
        }
}
if (RadioButton3->Checked)
{
        for(int a = 0; a<sizeZ; a+=1) {
        for(int i = 0; i<sizeY; i+=1) {
                gradientview[a*sizeY+i].r = gradientview[a*sizeY+i].g = gradientview[a*sizeY+i].b = absgrad[TrackBar->Position+i*sizeX+a*pagesize]/16;
        }
        }
}
lslice->Caption = IntToStr(TrackBar->Position) + " / " + IntToStr(TrackBar->Max);
PaintGL();

}
//---------------------------------------------------------------------------

void __fastcall TGradientForm::RadioButton1Click(TObject *Sender)
{
TrackBar->Max = sizeZ-1;
TrackBarChange(this);        
}
//---------------------------------------------------------------------------

void __fastcall TGradientForm::RadioButton2Click(TObject *Sender)
{
TrackBar->Max = sizeY-1;
TrackBarChange(this);
}
//---------------------------------------------------------------------------

void __fastcall TGradientForm::RadioButton3Click(TObject *Sender)
{
TrackBar->Max = sizeX-1;
TrackBarChange(this);
}
//---------------------------------------------------------------------------

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