Math is my weakness. Suppose I receive data from somewhere, and I want to render it in a Three.js scene. The data assumes that X is forward, Y is left, and Z is up, while Three.js assumes (based on the default camera view) that Z is backward, X is right, and Y is up. The data that I get are posit…

Ripping bread, or using a knife, are both trivial for humans compared to math though. So it’s not exactly the same comparison.

FWIW, I have converted a subtree in my scene from one basis to the Three basis, and now no matter what I do, the camera “up” axis is always sideways relative to the car I want to follow, and I’m having a hard time figuring how to fix it. No matter what I set the value of camera.up to, OrbitControls …

Idk, some tools may be harder to learn and work with, and yet they are vital for the job. if you do not use them, you will do poor job. the docs maybe could help with this by linking to khan academy videos or something?

@trusktr It is arbitrarily chosable by whoever designs their coordinate system, right? If we can account for that just as easily, then why not. Yes by how the axes are selected. Let’s consider why other cases are not legitimate to include in any solution. The code I have provided handles lef…

[image] gkjohnson: The code I have provided handles left handed coordinate systems – I didn’t say otherwise. Oh ok, that’s good. I didn’t see in your example how to specify handedness, and the README has no result for the search term “hand”. I don’t see the result I expect. Maybe I’m not exp…

[image] gkjohnson: I’m doing the same thing in my application using OrbitControls and everything works just fine I found my problem: camera.up must be specified before creating OrbitControls. Some parts of the code read it dynamically, while other parts do not. So there’s more things to cons…

[image] trusktr: If my experience designer doesn’t think about graphics math, is he doing a bad job? oh shit ) I cant tell you how many times I cursed designers who made assets without thinking about its use in realtime context. 50% of the time they create unuseable garbage, no matter how pre…

And robust basis conversion, not just with matrix transforms but around all tooling, would help reduce that percentage value (or I should say, make the designer’s output format less relevant)

@gkjohnson I forgot to include the screenshot in the above. I updated my reply.

@trusktr I also don’t see the result I expect. Maybe I’m not expecting the right thing, but in the following screenshot, -Z is forward (the default Three.js camera view) and for reference I oriented the axii on the left to show this. As you see I chose +X to be forward, but it looks like -X is act…

Convert from one coordinate system to another?

Questions

manthrax April 15, 2024, 6:27pm 47

Not to unneccesarily bump this thread, but it brought to mind this persons question I hit the other day, and apparently they had success with just flipping the scale of the Scene or Camera to change the handedness of the system:

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Convert from one coordinate system to another?

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