Terrain Pixel To World Coordinates

Is there a way to get the world coordinates of a given pixel in a terrain’s heightmap image? I’ve read through the source (Terrain.cpp) and I think I can do something like this if I have an access to the private member patchWorldOrigin_ then interpolate with this and the terrain’s node transformation but I’m not sure if this is the best approach.

Just to add, what I want to do is to add an overlay to the terrain that is aligned with the heightmap vertices. These overlayed quads will display a visualization of some sort using different colors that depends on the height of the terrain where the 4 vertices of the quad touches.

Example:
h1, h2, h3,
h4, h5, h6
h7, h8, h9

Above is a simple representation of the heightmap image’s pixels. What I want to do is overlay a quad per cell from h1 to h8. Note that these quads must be aligned with the vertices of the heightmap. TIA.

My personal code:

Vector3 Terrain::HeightMapToWorld(const IntVector2& pixelPosition) const
{
    if (!node_)
    {
        return Vector3::ZERO;
    }

    IntVector2 v2pos(pixelPosition.x_, numVertices_.y_ - 1 - pixelPosition.y_);
    float xPos = (float)(v2pos.x_ * spacing_.x_ + patchWorldOrigin_.x_);
    float zPos = (float)(v2pos.y_ * spacing_.z_ + patchWorldOrigin_.y_);
    Vector3 Lpos(xPos, 0, zPos);
    Vector3 WPos = node_->GetWorldTransform() * Lpos;
    WPos.y_ = GetHeight(WPos);

    return WPos;
}

edit: modifying the code to be consistent with Terrain code as it was not written for that class but for a helper class

Thanks @Lumak for a fast reply. I was hoping I wouldn’t need to edit the source file but if this is what you did in yours then I’m comfortable changing the source knowing that this was also how you did it.

You don’t have make changes on your end now. That function was added to the master and all you need to do is get the latest.

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