Can we trust y position of createPickingRay?

Questions
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1

I have a flat ground. On mouse move, I use createPickingRay to get the ground mesh position at the mouse pointer and move a sphere at this position.

The sphere is always correctly positionned, so I think there is no bug.
But when I log the sphere position with console.log I see that y position not always equal to 0 !

Sometime the sphere local position is different from absolute position, sometimes one is 0 while the other is -8 for example, sometimes both are valid or both invalid, this make no sense for me.

What does explain this behaviour and how to log the correct value ?
Note: computeWorldMatrix change nothing

thanks

2

Can you double check: on my machine it is not 8 or -8 but e.g. “-8.881784197001252e-16”. So this looks like a floating point error.

Rounding to some lower significant digits can help. Or if you compare, you could use epsilon.

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3

Thank you, sorry I am tired, I didn’t notice the e-16… :sweat_smile:

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