/*
** Name:      Rosette
** Author:    Paul Manias
** Copyright: DreamWorld Productions (c) 1997
** SAS/C:     sc Rosette.c link startup=lib:gms.o data=far opt math=standard nostackcheck
** Doc:       Draws various rosette patterns.
**
**
*/

#include <proto/games.h>
#include <math.h>

extern struct GMSBase *GMSBase;
APTR   PREFSNAME = DEFAULT;

struct GameScreen *screen;

void Rosette(void);

#define AMTCOLOURS 32

ULONG palette[AMTCOLOURS] = {
  0x000000,0x101010,0x171717,0x202020,0x272727,0x303030,0x373737,0x404040,
  0x474747,0x505050,0x575757,0x606060,0x676767,0x707070,0x777777,0x808080,
  0x878787,0x909090,0x979797,0xa0a0a0,0xa7a7a7,0xb0b0b0,0xb7b7b7,0xc0c0c0,
  0xc7c7c7,0xd0d0d0,0xd7d7d7,0xe0e0e0,0xe0e0e0,0xf0f0f0,0xf7f7f7,0xffffff
};

/***********************************************************************************/

void main(void)
{
  if (screen = AddScreenTags(TAGS_GAMESCREEN,NULL,
     GSA_AmtColours, AMTCOLOURS,
     GSA_Palette,    palette,
     TAGEND)) {

     ShowScreen(screen);
     InitJoyPorts();

     Rosette();

  DeleteScreen(screen);
  }
}

/***********************************************************************************/

void Rosette(void)
{
  WORD   offsetx = (screen->ScrWidth/2);
  WORD   offsety = (screen->ScrHeight/2);

  /* Experiment with the values below */
  double inside=3.0, radius=100.0, outside=3.0, f=0.5, edges=10;

  double t,angle,x,y;

  for (t = -inside/10; t < (outside/10); t += 0.1) {
    for (angle=0; angle < (2*PI); angle += 0.01) {
      x = radius*cos(angle)+t*radius*cos(angle*edges);
      y = radius*sin(angle)+t*radius*sin(angle*edges);
      DrawPixel(screen->Bitmap,(WORD)(x+offsetx),(WORD)(y*f+offsety),10);
    }
  }
  WaitLMB();
}