//===========================================================================
//                                                     2000 WANDERING SQUARES
//                                                Version 2 - High Definition
//                                                            21 October 2009
//
//                                 This is the beginning of a new foundation.
//                      Illustrating class construction, a great deal of code
//                    has been added to the class declaration and definition.
//  Note:  The rectangle method runs 10 times faster than the ellipse method.
//    The Canvas->Rectangle method runs 100 times faster than moving TImages.
//                              Trials runs 5-10 times faster than no trails.
//===========================================================================

#include <vcl.h>
#include <math.h>
#pragma hdrstop

#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;

#define POP 2000

// ====================================================== VARIABLES & CLASSES

bool stop = true;
TColor back = 0X79BBD7;
TColor fore = 0X4080FF;
int i;
int dist, nearest;
TColor color = 0X4080FF;

// this is a description of an abstract class of shapes
class shapes {
	public:
		double x, y ;
		double direction;
		double dx, dy;
		TColor color;
		float height, width;
		void erase (void) {
			Form1->PaintBox1->Canvas->Pen->Color = back;
			Form1->PaintBox1->Canvas->Brush->Color = back;
			Form1->PaintBox1->Canvas->Rectangle
				(x - 5, y - 5, x - 5 + width, y - 5 + height);
		}
		void draw (void) {
			Form1->PaintBox1->Canvas->Pen->Color = clBlack;
			Form1->PaintBox1->Canvas->Brush->Color = color;
			Form1->PaintBox1->Canvas->Rectangle
				(x - 5, y - 5, x - 5 + width, y - 5 + height);
		}
		void shrink (void) {
			erase();
			height *= .9; width *= .9;
			draw();
		}
		void grow (void) {
			erase();
			height *= 1.1; width *= 1.1;
			draw();
		}
		void move (void) {
			if (Form1->RadioGroupTrail->ItemIndex == 0) {
				Form1->PaintBox1->Canvas->Pen->Color = back;
				Form1->PaintBox1->Canvas->Brush->Color = back;
				Form1->PaintBox1->Canvas->Rectangle
					(x - 5, y - 5, x - 5 + width, y - 5 + height);
			}
			x += dx;
			y += dy;
			if (x > 695 || x < 5) {
				dx = -dx;
			}
			if (y > 695 || y < 5) {
				dy = -dy;
			}
			draw();
        }
} shape[POP];     // we now create an array of shapes-type objects

// ================================================================ FUNCTIONS

void initialize (void) {
	for (int i = 0; i < POP; i++) {
		shape[i].erase();
		shape[i].height = 10;
		shape[i].width = 10;
		shape[i].color = 0X4080FF;
		shape[i].direction =  double(i) / 3;
		shape[i].x = random(690) + 5;   // in a 700 x 700 world
		shape[i].y = random(690) + 5;   // in a 700 x 700 world
		shape[i].dy = double(random(100) - 50) / 25.00;
		shape[i].dx = double(random(100) - 50) / 25.00;
		Form1->PaintBox1->Canvas->Pen->Color = clBlack;
		Form1->PaintBox1->Canvas->Brush->Color = fore;
		Form1->PaintBox1->Canvas->Rectangle
			(shape[i].x - 5, shape[i].y - 5,
			shape[i].x - 5 + shape[i].width,
			shape[i].y - 5 + shape[i].height);
	}
}

void step (void) {
		for (int i = 0; i < POP; i++) {
			shape[i].move();
		}
}

void refresh (void) {
	for (int i = 0; i < POP; i++) {
		Form1->PaintBox1->Canvas->Pen->Color = clBlack;
		Form1->PaintBox1->Canvas->Brush->Color = shape[i].color;
		Form1->PaintBox1->Canvas->Rectangle
			(shape[i].x - 5, shape[i].y - 5,
			shape[i].x - 5 + shape[i].width,
			shape[i].y - 5 + shape[i].height);
	}
}

// =========================================================== EVENT HANDLERS

//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
	: TForm(Owner)
{
	DoubleBuffered = true;
	randomize();
	initialize();
}
//---------------------------------------------------------------------------
void __fastcall TForm1::ButtonShrinkClick(TObject *Sender)
{
	for (int i = 0; i < POP; i++) {
		shape[i].shrink();
	}
}
//---------------------------------------------------------------------------
void __fastcall TForm1::ButtonGrowClick(TObject *Sender)
{
	for (int i = 0; i < POP; i++) {
		shape[i].grow();
	}
}
//---------------------------------------------------------------------------
void __fastcall TForm1::RadioGroupTrailClick(TObject *Sender)
{
	Form1->Refresh();	
}
//---------------------------------------------------------------------------
void __fastcall TForm1::ButtonStepClick(TObject *Sender)
{
	stop = true;
	step();
}
//---------------------------------------------------------------------------
void __fastcall TForm1::ButtonRunClick(TObject *Sender)
{
	stop = false;
	while (stop == false) {
		Application->ProcessMessages();
		step();
	}
}
//---------------------------------------------------------------------------
void __fastcall TForm1::ButtonStopClick(TObject *Sender)
{
	stop = true;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::ButtonResetClick(TObject *Sender)
{
	initialize();
	Form1->Paint();
}
//---------------------------------------------------------------------------
void __fastcall TForm1::PaintBox1MouseDown(TObject *Sender, TMouseButton Button,
      TShiftState Shift, int X, int Y)
{
	stop = true;
	dist = 1000;
	for (i = 0; i < POP; i++) {
		if (abs(X - shape[i].x) + abs(Y - shape[i].y) < dist) {
			dist = abs(X - shape[i].x) + abs(Y - shape[i].y);
			nearest = i;
		}   
	}
			shape[nearest].color = color;
			Form1->PaintBox1->Canvas->Pen->Color = clBlack;
			Form1->PaintBox1->Canvas->Brush->Color = color;
			Form1->PaintBox1->Canvas->Rectangle(
				shape[nearest].x - 5, shape[nearest].y - 5,
				shape[nearest].x - 5 + shape[nearest].width,
				shape[nearest].y - 5 + shape[nearest].height);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::FormShow(TObject *Sender)
{
	refresh();
}
//---------------------------------------------------------------------------
void __fastcall TForm1::PaintBox1Paint(TObject *Sender)
{
	refresh();
}
//---------------------------------------------------------------------------
void __fastcall TForm1::ButtonSelectColorClick(TObject *Sender)
{
	if(Form1->ColorDialog1->Execute()) {
		color = ColorDialog1->Color;
    }	
}
//---------------------------------------------------------------------------