- // Capture attempt
- Math.abs(m[i].start.y - m[i].end.y) == 1 &&
- (m[1-i].end.x != m[i].end.x || m[1-i].end.y != m[i].end.y)
+ (
+ // Promotion attempt
+ m.end.x == (m.vanish[0].c == "w" ? 0 : V.size.x - 1) &&
+ other.vanish.length == 2 &&
+ other.vanish[1].p == V.KNIGHT &&
+ other.vanish[1].c == m.vanish[0].c
+ )
+ ||
+ (
+ // Moving attempt
+ !movingLikeCapture(m) &&
+ other.start.x == m.end.x &&
+ other.start.y == m.end.y
+ )
+ ||
+ (
+ // Capture attempt
+ movingLikeCapture(m) &&
+ other.end.x == m.end.x &&
+ other.end.y == m.end.y
+ )