45度地图 实际坐标与瓷砖坐标的互相转换

http://blog.sina.com.cn/s/blog_6056c88301010z6q.html

CCPoint DWMap::tilePosFromLocation(CCPoint location)
{
    // 触摸的位置信息必须减去瓷砖地图的位置信息,因为地图的位置可能在滚动变化
    CCPoint pos = ccpSub(location, m_pTileMap->getPosition());
   
    float halfMapWidth = m_pTileMap->getMapSize().width * 0.5f;
    float mapHeight    = m_pTileMap->getMapSize().height;
   
    float tileWidth    = 0.0f;
    float tileHeight   = 0.0f;
   
    //这里需要注意Retina中的TileSize
    if(CCDirector::sharedDirector()->isRetinaDisplay())
    {
        tileWidth    = m_pTileMap->getTileSize().width  / 2;
        tileHeight   = m_pTileMap->getTileSize().height / 2;
    }
    else
    {
        tileWidth    = m_pTileMap->getTileSize().width;
        tileHeight   = m_pTileMap->getTileSize().height;
    }
   
    CCPoint tilePosDiv = CCPointMake(pos.x / tileWidth, pos.y / tileHeight);
    float inverseTileY = mapHeight - tilePosDiv.y;
    // 将得到的计算结果转换成 int,以确保得到的是整数
    float posX = (int)(inverseTileY + tilePosDiv.x - halfMapWidth);
    float posY = (int)(inverseTileY - tilePosDiv.x + halfMapWidth);
   
    return CCPointMake(posX, posY);
}


CCPoint DWMap::LocationFromtilePos(CCPoint tilePos)
{
    float halfMapWidth = m_pTileMap->getMapSize().width * 0.5f;
    float mapHeight    = m_pTileMap->getMapSize().height;
   
    float tileWidth    = 0.0f;
    float tileHeight   = 0.0f;
   
    if(CCDirector::sharedDirector()->isRetinaDisplay())
    {
        tileWidth    = m_pTileMap->getTileSize().width  / 2;
        tileHeight   = m_pTileMap->getTileSize().height / 2;
    }
    else
    {
        tileWidth    = m_pTileMap->getTileSize().width;
        tileHeight   = m_pTileMap->getTileSize().height;
    }
   
    CCPoint tilePosDiv;
    CCPoint pos;
   
    tilePosDiv.y = mapHeight - (tilePos.x + tilePos.y)/2;
    tilePosDiv.x = (tilePos.x - tilePos.y)/2 + halfMapWidth;
   
    pos.x = tilePosDiv.x * tileWidth;
    pos.y = tilePosDiv.y * tileHeight;
   
    return ccpAdd(m_pTileMap->getPosition(),pos);
}