Axes, orientations and origin points

only_a_ptr

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3D is hard. XYZ sounds simple enough, but as soon as you ask "which way is left/up/right", you run into ambiguities. I'd like to sum up what we know, in a short format. The reason I'm posting this:
  • In the game, +Y is up, +X is right, +Z is forward. See this image in OGRE docs. This "Y is up" arrangement is standard in 3D renderers and game engines.
  • In Blender, +Z is up, +X is right, -Y is forward. See top of this Blender-Docs page. This "Z is up" arrangement is standard in mathematics.
  • For historical reasons, the game mostly expects assets to have the axes wrong and tries to compensate by rotating, causing further confusion.
All the meshes in default resources have their axes wrong, using the Blender convention instead of OGRE convention. In the image, red is X, green is Y, blue is Z, same as in Blender gizmo (standard coloring).
1702688139048.png


This is the switch in blender2ogre that gets things right:
1702688679002.png


What I'm wondering is - if the game gets it consistently wrong all the time, is it really "wrong" or just "our own quirky way of doing things"? Problem is I'm not sure it's consistent:
Let me know if you also had trouble with this.
 
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