ios - 优化在 Ray Wenderlich 上发现的 2d 瓦片碰撞（objective-c）

Question

我一直在使用 sprite kit 构建平台游戏，但在尝试更改玩家 spritenode 的大小以更好地匹配艺术时遇到了问题。我将 Ray Weinderlich 教程中的这个算法与 JSTileMap 结合使用。

 - (void)checkForAndResolveCollisionsForPlayer:(Player *)player forLayer:(TMXLayer *)layer
{
  NSInteger indices[8] = {7, 1, 3, 5, 0, 2, 6, 8};
  player.onGround = NO;  ////Here
  for (NSUInteger i = 0; i < 8; i++) {
    NSInteger tileIndex = indices[i];

    CGRect playerRect = [player collisionBoundingBox];
    CGPoint playerCoord = [layer coordForPoint:player.desiredPosition];

    NSInteger tileColumn = tileIndex % 3;
    NSInteger tileRow = tileIndex / 3;
    CGPoint tileCoord = CGPointMake(playerCoord.x + (tileColumn - 1), playerCoord.y + (tileRow - 1));

    NSInteger gid = [self tileGIDAtTileCoord:tileCoord forLayer:layer];
    if (gid != 0) {
      CGRect tileRect = [self tileRectFromTileCoords:tileCoord];
      //NSLog(@"GID %ld, Tile Coord %@, Tile Rect %@, player rect %@", (long)gid, NSStringFromCGPoint(tileCoord), NSStringFromCGRect(tileRect), NSStringFromCGRect(playerRect));
      //1
      if (CGRectIntersectsRect(playerRect, tileRect)) {
        CGRect intersection = CGRectIntersection(playerRect, tileRect);
        //2
        if (tileIndex == 7) {
          //tile is directly below Koala
          player.desiredPosition = CGPointMake(player.desiredPosition.x, player.desiredPosition.y + intersection.size.height);
          player.velocity = CGPointMake(player.velocity.x, 0.0); ////Here
          player.onGround = YES; ////Here
        } else if (tileIndex == 1) {
          //tile is directly above Koala
          player.desiredPosition = CGPointMake(player.desiredPosition.x, player.desiredPosition.y - intersection.size.height);
        } else if (tileIndex == 3) {
          //tile is left of Koala
          player.desiredPosition = CGPointMake(player.desiredPosition.x + intersection.size.width, player.desiredPosition.y);
        } else if (tileIndex == 5) {
          //tile is right of Koala
          player.desiredPosition = CGPointMake(player.desiredPosition.x - intersection.size.width, player.desiredPosition.y);
          //3
        } else {
          if (intersection.size.width > intersection.size.height) {
            //tile is diagonal, but resolving collision vertically
            //4
            player.velocity = CGPointMake(player.velocity.x, 0.0); ////Here
            float intersectionHeight;
            if (tileIndex > 4) {
              intersectionHeight = intersection.size.height;
              player.onGround = YES; ////Here
            } else {
              intersectionHeight = -intersection.size.height;
            }
            player.desiredPosition = CGPointMake(player.desiredPosition.x, player.desiredPosition.y + intersection.size.height );
          } else {
            //tile is diagonal, but resolving horizontally
            float intersectionWidth;
            if (tileIndex == 6 || tileIndex == 0) {
              intersectionWidth = intersection.size.width;
            } else {
              intersectionWidth = -intersection.size.width;
            }
            //5
            player.desiredPosition = CGPointMake(player.desiredPosition.x  + intersectionWidth, player.desiredPosition.y);
          }
        }
      }
    }
  }
  //6
  player.position = player.desiredPosition;
}

我只是想知道是否有更有效的方法或不同的算法来处理这种性质的瓷砖碰撞（与玩家周围的瓷砖接触），如果我的玩家的精灵被调整为更大，这将考虑在内。实际上，如果我将精灵的大小调整为高于两个瓦片高度或两个瓦片宽度，因为瓦片是 16 像素 x 16 像素，它会导致整个瓦片碰撞分解，因为它使用 3 x 3 网格来处理瓦片碰撞。我的目标是能够处理瓷砖碰撞，而不必向每个“墙”瓷砖添加物理体，并且让算法功能独立于玩家大小。或者至少能够选择性能开销最小的选项。几个星期以来，我一直在思考和研究瓷砖碰撞，这是我见过的仅有的两个选项。

标签： iosobjective-cperformancejstilemap