Unbenannt

#define SINE_MAX_X   (4)
#define SINE_OMEGA_X (0.1386)
#define SINE_PHI_X   (0)

#define SINE_MAX_Y   (4)
#define SINE_OMEGA_Y (0.1248)
#define SINE_PHI_Y   (0)

void catcha_reverse_sine_transform(catcha* cat) {
	int x,y,shift;

	
	// transform in x-direction
	for(y=0; y<CATCHA_H; y++) {
		shift = -(int)(SINE_MAX_X*sin(SINE_OMEGA_X*y+SINE_PHI_X));
		if(shift > 0) {
			for(x=0; x<CATCHA_W; x++)
				cat->image[x][y] = (x+shift<CATCHA_W)?cat->image[x+shift][y]:0xFF;
		} else {
			for(x=CATCHA_W-1; x>=0; x--)
				cat->image[x][y] = (x+shift>=0)?cat->image[x+shift][y]:0xFF;
		}
		cat->image[(CATCHA_W-6)-shift][y] = 0x01;
	}

	// transform in y-direction
	for(x=0; x<CATCHA_W; x++) {
		shift = -(int)(SINE_MAX_Y*sin(SINE_OMEGA_Y*x+SINE_PHI_Y));
		if(shift > 0) {
			for(y=0; y<CATCHA_H; y++)
				cat->image[x][y] = (y+shift<CATCHA_H)?cat->image[x][y+shift]:0xFF;
		} else {
			for(y=CATCHA_H-1; y>=0; y--)
				cat->image[x][y] = (y+shift>=0)?cat->image[x][y+shift]:0xFF;
		}
		cat->image[x][(CATCHA_H-4)-shift] = 0x01;
	}

}