Why are scene.pointerX and scene.pointerY not integers?

Questions
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7

I can reproduce it on chrome. Here the scene.PointerX values appear as floats (e.g. 101.5).
It can be influenced when I change the size of the debugging console or the size of the code window. It then changes between integer and float.

Not quite sure what causes this. Browsers often provide coordinates in device-independent pixels (DIPs) and then multiply them by the DPR to get actual pixel values. This can lead to floating-point values. My guess would be:

When the canvas is created, it might have a certain size in logical pixels, but due to the DPR, these logical pixels correspond to fractional physical pixels on high-DPI screens. This is why you see fractional pointer coordinates. :sweat_smile:

If you depent for some reason on integers, consider using Math.round() :nerd_face:

Just an idea:
You can retrieve the DPR using window.devicePixelRatio and use it to adjust the coordinates accordingly.

scene.onBeforeRenderObservable.add(function(){
    var dpr = window.devicePixelRatio || 1;
    var x = Math.round(scene.pointerX * dpr);
    var y = Math.round(scene.pointerY * dpr);
    console.log(x, y)
})