 | | Re: LDraw coordinate system driving me crazy
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(...) I've been having difficulty with importing/exporting .dat files from SketchUp. In SketchUp, if you stand at the Origin; X is right, Y is forward, and Z is up. The LDraw Primitives Reference ((URL)) says the LDraw axes are: X is right, Y is (...) (18 years ago, 19-Nov-06, to lugnet.cad.dev, FTX)
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| | Re: LDraw coordinate system driving me crazy
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(...) In LDraw +z is backwards, not forwards or more strictly +Z points away from the camera when X is right and -Y is up. Tim (18 years ago, 19-Nov-06, to lugnet.cad.dev, FTX)
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| | Re: LDraw coordinate system driving me crazy
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Hi, Here's my box test model in SketchUp. (The above model is the same model unfolded.) (URL) When I export this model to a .dat and open it in LDView, the green side is the top-view, blue is the front view (as expected), and I would expect the (...) (18 years ago, 19-Nov-06, to lugnet.cad.dev, FTX)
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| | Re: LDraw coordinate system driving me crazy
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(...) That looks like a correct mapping to me. Unless I'm mistaken the red and orange are on the same sides in both pictures. The unwrapped boxes are definitely identical and unless you've moved them in one or the other the whole thing is right. Tim (18 years ago, 19-Nov-06, to lugnet.cad.dev, FTX)
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| | Re: LDraw coordinate system driving me crazy
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(...) Google uses the right handed system but indeed rotated by 90 degrees, LDraw also uses the right handed system but 180 degrees rotated. It should not matter how you show the model, the coordinates are interchangeable, but if you want to use (...) (18 years ago, 19-Nov-06, to lugnet.cad.dev)
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| | Re: LDraw coordinate system driving me crazy
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(...) I agree with Tim. It looks fine to me. If there were any mirroring going on, then either the orange and red would be swapped on the unwrapped box, or the green and grey would be swapped. The picture in LDView has a rotated camera angle (...) (18 years ago, 19-Nov-06, to lugnet.cad.dev, FTX)
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| | Re: LDraw coordinate system driving me crazy
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A sincere thanks to all of you. Your comments made me go back over (again) my export code, and I found an error. Now it works as expected. I was getting funny rotations because I mis-ordered the elements of the transformation matrix, duh. Seems (...) (18 years ago, 20-Nov-06, to lugnet.cad.dev, FTX)
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