- if (curblock & 16 && !BlockFree(scr, x, y-1, z & 208)) return 0;
- if (curblock & 32 && !BlockFree(scr, x, y+1, z & 224)) return 0;
- if (curblock & 64 && !BlockFree(scr, x+1, y, z & 112)) return 0;
- if (curblock & 128 && !BlockFree(scr, x-1, y, z & 176)) return 0;
- if ((z = GetBlock(scr, y-1, x)) & 32) return 1; //stuck to block below
- if (z > BT_none) return 0; //some other piece below
- return 1; //nothing below
+ if (curblock & 0x10 && !BlockFree(scr, x, y-1, z & 0xD0)) return 0;
+ if (curblock & 0x20 && !BlockFree(scr, x, y+1, z & 0xE0)) return 0;
+ if (curblock & 0x40 && !BlockFree(scr, x+1, y, z & 0x70)) return 0;
+ if (curblock & 0x80 && !BlockFree(scr, x-1, y, z & 0xB0)) return 0;
+ if ((z = GetBlock(scr, y-1, x)) & 0x20) return 1; // stuck to block below
+ if (z > BT_none) return 0; // some other piece below
+ return 1; // nothing below