hello to you all,
There is a small problem in rotating a point using fixedpoint. The rotation
wont work and I don't know why.
If you could help me I would appriciate it.
Here's the source I compile. It's not much but it's all there is ;)
Ok, see what you do with it. Have a nice day.
thanx Richard van Berkum
int sintab[360];
int costab[360];
int *sinptr;
int *cosptr;
void main(void)
{
  int sin;
  int cos;
  int x1, x2, y1, y2;
  int offset;
  signed int x= -20, y = 20;  // x and y coordinates
        setvga(0x13);
        sinptr = sintab;      // ptr to tabel
        cosptr = costab;      // ptr to tabel
        sin = *(sinptr+4);    //angle of rotation
        cos = *(cosptr+4);    //angle of rotation
        for(int i = 0; i < 360; i++)
                {
                   x1 = (cos*x);    
                   y1 = (sin*y);
                   x2 = x1 - y1;    // cos*x - sin*y
                   x1 = (sin*x);
                   y1 = (cos*y);
                   y1 = x1 + y1;    // sin*x + cos*y
                   x2 /= 16384;
                   y1 /= 16384;
                   x = x2;          // new x and y
                   y = y1;
                   offset = y * 320;
                offset += x;
                offset +=center;
                pokeb(0xa000, offset, 2);
        }
  getch();
  setvga(3);
}
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