+int
+pixel_hit_rocks(float x, float y)
+{
+ int b = bucket(x, y);
+ if(pixel_hit_in_bucket(b, x, y)) return 1;
+ if(pixel_hit_in_bucket(b-1, x, y)) return 1;
+ if(pixel_hit_in_bucket(b-bw, x, y)) return 1;
+ if(pixel_hit_in_bucket(b-bw-1, x, y)) return 1;
+ return 0;
+}
+