How to get cartesian coords of objects from tiled's isometric map?

Questions
1

Hello, I’m working on simple isometric engine. But I don’t understand how to convert coords of objects from Tiled to cartesian coords. For example:

1594362046027

In file:

I’m using a simple formaula for drawing tiles:

screen.x = (map.x - map.y) * TILE_WIDTH_HALF;
screen.y = (map.x + map.y) * TILE_HEIGHT_HALF;

Could you please provide a formula for converting or a basic algorithm how work coords in Tiled?

2

Is your map “Isometric” or “Isometric (staggered)”? The coordinates work differently in each.

If it’s the regular isometric, the same question was asked just a few days ago:

3

It is “Isometric”. I saw that topic thanks. But I want to get exact coordinates (not column and row).

For example, in a file my object is represented:

<object id="7" x="154" y="36" width="50" height="50"/>

I think maybe to use column and row and a offset. But I can’t derive a correct formula for the offset.

4

This is the Tiled code that does the translation from isometric tile coordinates to pixels. As you can see here, the location depends on both x and y, as well as the map’s height.

QPointF IsometricRenderer::tileToScreenCoords(qreal x, qreal y) const
{
    const int tileWidth = map()->tileWidth();
    const int tileHeight = map()->tileHeight();
    const int originX = map()->height() * tileWidth / 2;

    return QPointF((x - y) * tileWidth / 2 + originX,
                   (x + y) * tileHeight / 2);
}
5

Thank you! I find it!

QPointF IsometricRenderer::pixelToScreenCoords(qreal x, qreal y) const
{
    const int tileWidth = map()->tileWidth();
    const int tileHeight = map()->tileHeight();
    const int originX = map()->height() * tileWidth / 2; // it doesn't need in my code
    const qreal tileY = y / tileHeight;
    const qreal tileX = x / tileHeight;

    return QPointF((tileX - tileY) * tileWidth / 2 + originX,
                   (tileX + tileY) * tileHeight / 2);
}

QPolygonF IsometricRenderer::pixelRectToScreenPolygon(const QRectF &rect) const
{
    QPolygonF polygon;
    polygon << QPointF(pixelToScreenCoords(rect.topLeft()));
    polygon << QPointF(pixelToScreenCoords(rect.topRight()));
    polygon << QPointF(pixelToScreenCoords(rect.bottomRight()));
    polygon << QPointF(pixelToScreenCoords(rect.bottomLeft()));
    return polygon;
}

My object has coords: X: 134.0, Y: -91.0

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