Question

我正在使用带有四边形的VertexArray来制作TileMap以进行一些测试。我试图找出如何找出游戏对象的顶点（四边形）。

bool load(const std::string& tileset, sf::Vector2u tileSize, const int* tiles, unsigned int width, unsigned int height)
{

    // load the tileset texture
    if (!m_tileset.loadFromFile(tileset))
        return false;

    // resize the vertex array to fit the level size
    m_vertices.setPrimitiveType(sf::Quads);
    m_vertices.resize(width * height * 4);

    // populate the vertex array, with one quad per tile
    for (unsigned int i = 0; i < width; ++i)
    for (unsigned int j = 0; j < height; ++j)
    {
        // current tile number
        int tileNumber = tiles[i + j * width];

        // find its position in the tileset texture
        int tu = tileNumber % (m_tileset.getSize().x / tileSize.x);
        int tv = tileNumber / (m_tileset.getSize().x / tileSize.x);

        //std::cout << tu << " : " << tv << std::endl; <- Used this to out put it all, but it kept on showing the same coordinates and slowed the program down a lot.

        // current tile's quad
        sf::Vertex* quad = &m_vertices[(i + j * width) * 4];

        // 4 corners
        quad[0].position = sf::Vector2f(i * tileSize.x, j * tileSize.y);
        quad[1].position = sf::Vector2f((i + 1) * tileSize.x, j * tileSize.y);
        quad[2].position = sf::Vector2f((i + 1) * tileSize.x, (j + 1) * tileSize.y);
        quad[3].position = sf::Vector2f(i * tileSize.x, (j + 1) * tileSize.y);

        // 4 coordinates
        quad[0].texCoords = sf::Vector2f(tu * tileSize.x, tv * tileSize.y);
        quad[1].texCoords = sf::Vector2f((tu + 1) * tileSize.x, tv * tileSize.y);
        quad[2].texCoords = sf::Vector2f((tu + 1) * tileSize.x, (tv + 1) * tileSize.y);
        quad[3].texCoords = sf::Vector2f(tu * tileSize.x, (tv + 1) * tileSize.y);
    }

    return true;
}

私人：

virtual void draw(sf::RenderTarget& target, sf::RenderStates states) const
{
    // apply the transform
    states.transform *= getTransform();

    // apply the tileset texture
    states.texture = &m_tileset;

    // draw the vertex array
    target.draw(m_vertices, states);
}
sf::VertexArray m_vertices;
sf::Texture m_tileset;

};

我已经尝试了其他一些方法来展示它们，但这一切要么不能正确执行，要么会使程序放慢速度。有人能指出我正确的方向吗？

此致

Answer 1

使用if语句检查TU和TV整数，以及您的磁贴编号，因此请检查那些是否与您要检查对象的磁贴相等。

if（tu＆amp; tv == 1）{std :: cout＆lt;＆lt; ＆＃34; 1＆＃34; ＆LT;＆LT;的std :: ENDL;}

如何从VertexArray SFML中查找顶点的坐标

1 个答案: