+ if(abs(sx + c->x) < SNAP)
+ c->x = sx;
+ else if(abs((sx + sw) - (c->x + c->w)) < SNAP)
+ c->x = sw - c->w - 2 * BORDERPX;
+ if(abs((sy + bh) - c->y) < SNAP)
+ c->y = sy + bh;
+ else if(abs((sy + sh) - (c->y + c->h)) < SNAP)
+ c->y = sh - c->h - 2 * BORDERPX;