News for hackers. Stuff that matters.
Re:Show HN: Cross-platform open-source 3D modeling software by tezza on Saturday December 01, 2018 @08:18AM (#18576648)
Does this use the same coordinate space[1] as Maya , or does it use the same coordinate space as Blender ?

Blender has no end of hidden trouble importing to Unity because Unity chose to be the same as Maya

[1] https://blender.stackexchange.com/questions/471/is-it-possib...

Re:Show HN: Cross-platform open-source 3D modeling software by huxingyi on Saturday December 01, 2018 @09:34AM (#18576924)
Dust3D use right-handed coordinate space, X - front view, Z - side view, Y - up. I am not quite sure what exactly coordinate space other software use, but I make sure the exported fbx looks as the same in Unity, and the exported glb looks as the same in Godot.
Re:Show HN: Cross-platform open-source 3D modeling software by starbeast on Saturday December 01, 2018 @11:39AM (#18577465)
If the fbx loads into Unity fine, are you not using a left handed system, or are you flipping it on export?

edit - I'm an idiot, Unity does its own conversion to left handed on import.

Re:Show HN: Cross-platform open-source 3D modeling software by iKlsR on Saturday December 01, 2018 @09:39AM (#18576936)
OT: First time ever seeing a post of mine `randomly` linked here on HN. :)
Re:Show HN: Cross-platform open-source 3D modeling software by sneak on Saturday December 01, 2018 @08:38AM (#18576722)
TIL.

The fact that gaming and Maya use one (Y-up) and that CAD and Blender use another (Z-up) brings the classic xkcd to mind.

https://xkcd.com/927/

Re:Show HN: Cross-platform open-source 3D modeling software by swsieber on Saturday December 01, 2018 @09:01AM (#18576789)
The fact that there are only 2 makes me think that it doesn't apply though. I just hope nobody trise to go make a third.
Re:Show HN: Cross-platform open-source 3D modeling software by Impossible on Saturday December 01, 2018 @12:03PM (#18577613)
There are more than two, Unreal has a coordinate system so special that Tim Sweeney apologized for it.

https://mobile.twitter.com/timsweeneyepic/status/95266147450...

Re:Show HN: Cross-platform open-source 3D modeling software by TeMPOraL on Saturday December 01, 2018 @09:21AM (#18576871)
There are also left-handed and right-handed coordinate systems...
Re:Show HN: Cross-platform open-source 3D modeling software by pzone on Saturday December 01, 2018 @10:34AM (#18577154)
This is correct. Most CG and 3d software (Max, Maya, Blender, CAD) uses a right handed coordinate system, which matches the convention in physics, however they vary in their choice of Y up or Z up. Video games almost always use a left-handed coordinate system with Y up. This is because DirectX and OpenGL chose to represent pixels on-screen with (X,Y) coordinates with the Z coordinate increasing as rays extend from the eye outward.
Re:Show HN: Cross-platform open-source 3D modeling software by swsieber on Saturday December 01, 2018 @03:57PM (#18578882)
Wow, I had no idea it was so varied
Re:Show HN: Cross-platform open-source 3D modeling software by TeMPOraL on Saturday December 01, 2018 @04:34PM (#18579098)
To add to the confusion, while in both OpenGL and DirectX treat Z axis as depth, DirectX uses a left-handed coordinate system, while OpenGL uses mostly[0] right-handed one.

--

[0] - https://stackoverflow.com/questions/4124041/is-opengl-coordi...

Re:Show HN: Cross-platform open-source 3D modeling software by blattimwind on Saturday December 01, 2018 @04:41PM (#18579138)
OpenGL-the-interface is kinda neither (screenspace aside), since the application supplies/does all transformations (glFrustum and friends are long deprecated).
Re:Show HN: Cross-platform open-source 3D modeling software by Narann on Saturday December 01, 2018 @09:19AM (#18576861)
Most CGI software where in-house software before being commercial. So the "what others do?" question never popped. :)
Re:Show HN: Cross-platform open-source 3D modeling software by throwaway2016a on Saturday December 01, 2018 @10:08AM (#18577058)
I think that XKCD only really applies in systems where there is an infinite number of possible ways to do something. While there are a lot of ways you can configure a coordinate system the number of reasonable / non-intentionally obtuse ways is finite.