shithub: qk1

ref: 2feac9be1d1bebe1a05a47c0adf0254228ca558d
dir: /r_surf_block.h/

#define N 3
static void
DrawSurfaceBlock(unsigned *lp[N], unsigned lw, int nb)
{
	int b, v, i, j, lightstep[N], light[N], lightleft[N], lightright[N];
	int lightleftstep[N], lightrightstep[N];
	pixel_t	*psource, *prowdest;

	psource = pbasesource;
	prowdest = prowdestbase;

	for (v=0 ; v<nb ; v++)
	{
		for(j = 0; j < N; j++){
			lightleft[j] = lp[j][0];
			lightright[j] = lp[j][1];
			lp[j] += lw;
			lightleftstep[j] = (lp[j][0] - lightleft[j]) >> (4-mip);
			lightrightstep[j] = (lp[j][1] - lightright[j]) >> (4-mip);
		}

		for (i=0 ; i<16>>mip; i++)
		{
			for(j = 0; j < N; j++){
				lightstep[j] = (lightleft[j] - lightright[j]) >> (4-mip);
				light[j] = lightright[j];
			}

			for(b = (16>>mip)-1; b >= 0; b--){
				prowdest[b] = addlight(psource[b], light[0], light[1], light[2]);
				for(j = 0; j < N; j++)
					light[j] += lightstep[j];
			}

			psource += sourcetstep;
			prowdest += surfrowbytes;

			for(j = 0; j < N; j++){
				lightright[j] += lightrightstep[j];
				lightleft[j] += lightleftstep[j];
			}
		}

		if (psource >= r_sourcemax)
			psource -= r_stepback;
	}
}
#undef N