praktika-cpp-2PO07/ColorChooser/Unit1.cpp

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

#include <vcl.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
bool up = true;
int mode = 0;
int r=255,g=255,b=255;

//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------


void __fastcall TForm1::FormPaint(TObject *Sender)
{     int h2 = ClientHeight/2;
      int w = ClientWidth;
      TRect aRect = Rect(0,0,ClientWidth,ClientHeight);
      Canvas->Brush->Color=(TColor)0xffffff;
      Canvas->FillRect(aRect);
      //Blue
      TRect b1 = Rect(20,20,120,h2);
      Canvas->Brush->Color=(TColor)0;
      Canvas->FillRect(b1);
      b1 = Rect(20,h2-((b*(h2-20)/255)),120,h2);
      Canvas->Brush->Color=clBlue;
      Canvas->Pen->Color=clBlue;
      Canvas->FillRect(b1);
      //Green
      TRect g1 = Rect(140,20,240,h2);
      Canvas->Brush->Color=(TColor)0;
      Canvas->FillRect(g1);
      g1 = Rect(140,h2-((g*(h2-20)/255)),240,h2);
      Canvas->Brush->Color=(TColor)0x00FF00;
      Canvas->Pen->Color=(TColor)0x00FF00;
      Canvas->FillRect(g1);
      //Red
      TRect r1 = Rect(260,20,360,h2);
      Canvas->Brush->Color=(TColor)0;
      Canvas->FillRect(r1);
      r1 = Rect(260,h2-((r*(h2-20)/255)),360,h2);
      Canvas->Brush->Color=clRed;
      Canvas->Pen->Color=clRed;
      Canvas->FillRect(r1);
      //Cursor
      if(mode==0) b1 = Rect(20,20,120,h2);
      else if(mode==1) b1 = Rect(140,20,240,h2);
      else if(mode==2) b1 = Rect(260,20,360,h2);
      Canvas->Pen->Color=clRed;
      Canvas->MoveTo(b1.Left,b1.Bottom);
      Canvas->LineTo(b1.right,b1.Bottom);
      Canvas->Pen->Color=clGreen;
      Canvas->MoveTo(b1.Left,b1.Bottom+1);
      Canvas->LineTo(b1.right,b1.Bottom+1);
      Canvas->Pen->Color=clBlue;
      Canvas->MoveTo(b1.Left,b1.Bottom+2);
      Canvas->LineTo(b1.right,b1.Bottom+2);
      //BGR
      TRect all = Rect(0,h2+10,w,h2*2);
      Canvas->Brush->Color=(TColor)(b<<16)|(g<<8)|r;
      Canvas->FillRect(all);
      //Text
      Canvas->Brush->Color=clWhite;
      Canvas->Font->Color=clRed;
      Canvas->TextOutA(23,ClientHeight-30,"bgr= 0x"+IntToHex((b<<16)|(g<<8)|r,6));
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormKeyDown(TObject *Sender, WORD &Key,
      TShiftState Shift)
{
     if(((int)Key)==VK_LEFT) {
                mode--;
                if(mode<0) mode=2;
      }
      if(((int)Key)==VK_RIGHT) {
                mode++;
                if(mode>2) mode=0;
      }
      if(((int)Key)==VK_UP) {
                if(mode==0) b++;
                else if(mode==1) g++;
                else if(mode==2) r++;
                if(b>255) b=0;
                if(g>255) g=0;
                if(r>255) r=0;
      }
      if(((int)Key)==VK_DOWN) {
                if(mode==0) b--;
                else if(mode==1) g--;
                else if(mode==2) r--;
                if(b<0) b=255;
                if(g<0) g=255;
                if(r<0) r=255;
      }
      FormPaint(this);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormMouseMove(TObject *Sender, TShiftState Shift,
      int X, int Y)
{
      if(up) return;
      int h2 = ClientHeight/2;
      //B
      if((X>=20) && (X<=120) && (Y>=20) && (Y<=h2)) {
            b = 255-(Y-20)*255/(h2-20);
            mode = 0;
      }
      //G
      if((X>=140) && (X<=240) && (Y>=20) && (Y<=h2)) {
            g = 255-(Y-20)*255/(h2-20);
            mode = 1;
      }
      //R
      if((X>=260) && (X<=360) && (Y>=20) && (Y<=h2)) {
            r = 255-(Y-20)*255/(h2-20);
            mode = 2;
      }
      FormPaint(this);
}
//---------------------------------------------------------------------------

void __fastcall TForm1::FormMouseDown(TObject *Sender, TMouseButton Button,
      TShiftState Shift, int X, int Y)
{
      up = false;  
}
//---------------------------------------------------------------------------

void __fastcall TForm1::FormMouseUp(TObject *Sender, TMouseButton Button,
      TShiftState Shift, int X, int Y)
{
      up = true;  
}
//---------------------------------------------------------------------------