#define _USE_MATH_DEFINES
#include <vcl.h>
#include <cmath>
#pragma hdrstop
#ifndef M_PI
#define M_PI 3.1415926535897932384626433832795
#endif
#include "Unit1.h"
 
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
 
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner){}
 
static HBRUSH  g_brush = NULL;
static HBITMAP g_bmp   = NULL;
static HDC     g_hdc   = NULL;
static int     g_size  = 0;
 
void __fastcall TForm1::FormCreate(TObject *Sender){
        g_brush = CreateSolidBrush(RGB(0, 0, 0));
        g_size  = Width / 2;
        g_bmp   = CreateCompatibleBitmap(Canvas->Handle, g_size, g_size); 
        g_hdc   = CreateCompatibleDC(Canvas->Handle);
        SelectObject(g_hdc, g_bmp);
 
        Timer1->Enabled  = true;
        Timer1->Interval = 80;
}
 
void __fastcall TForm1::Timer1Timer(TObject *Sender){
    POINT dots[3];
    int   pos    = g_size / 2;
    int   radius = pos - 4;
 
    RECT rc = { 0, 0, g_size, g_size };
 
        FillRect(g_hdc, &rc, g_brush);
        Ellipse(g_hdc, pos - radius, pos - radius, pos + radius, pos + radius);
        HGDIOBJ old = SelectObject(g_hdc, g_brush);
        
        double theta;
        double step  = 360.0 / 8.;
        double off   = (double)GetTickCount() / 20.;
        //рисуем пропеллеры
        for(int i = 0; i < 4; ++i){
                theta = off * (M_PI / 180.);
                dots[0].x = dots[0].y = pos;
                dots[1].x = pos + radius * std::cos(theta);
                dots[1].y = pos + radius * std::sin(theta);
 
                theta = (off + step) * (M_PI / 180.);
                dots[2].x = pos + radius * std::cos(theta);
                dots[2].y = pos + radius * std::sin(theta);
 
                Polygon(g_hdc, dots, sizeof(dots)/sizeof(dots[0]));
                off += step * 2.;
        }
        SelectObject(g_hdc, old);
        //выводим на форму
        BitBlt(Canvas->Handle, (Width - g_size)/2, (Height - g_size)/2, 
               g_size, g_size, g_hdc, 0, 0, SRCCOPY);
}
 
void __fastcall TForm1::FormDestroy(TObject *Sender){
        DeleteObject(g_brush);
        DeleteObject(g_bmp);
        DeleteDC(g_hdc);
}