Coordinate Systems

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Verge3D

In Verge3D we use right-handed coordinate system with the Y axis pointing in the up direction. If we place the camera so X axis points right, then the Z axis will point forward (to the viewer).

Y up axis.png

Right-handed means when you place an imaginary screw perpendicular to both X and Y and then rotate X axis to Y axis, the screw goes in the direction of Z axis.

Right handed rotation.png

Blender

Blender uses right-handed coordinate system with Z axis pointing in the up direction.

Z up axis.png

This convention is different from Verge3D, however in most cases you don't need to worry about it. When you export you scene from Blender to glTF, we automatically convert all coordinates by swapping Y/Z axes. Basically, you animate and move your objects in Blender, and these movements are handled by Verge3D properly.

There is one exception to this - if you're going to use JavaScript to script your apps (but not Puzzles, see below), you need to convert object coordinates from Z-up to Y-up system:

X (Blender) ->  X (Verge3D)
Y (Blender) -> -Z (Verge3D)
Z (Blender) ->  Y (Verge3D)
Compare screenshots above to see why Y becomes -Z.

3ds Max

Autodesk 3ds Max uses right-handed coordinate system with Z axis pointing in the up direction. This convention is similar to Blender.

Z up axis.png

Maya

By default, Autodesk Maya uses right-handed coordinate system with Y axis pointing in the up direction.

Y up axis.png

This convention is similar to Verge3D so there is nothing to worry about, especially if you don't set World Coordinate System to Z:

Maya coordinate system.jpg

Puzzles

In Puzzles we use coordinates depending on the loaded scene. If the scene was made in Blender or 3ds Max, we use Z-up coordinate system. If the scene was exported from Maya, we use Y-up coordinate system. That means, that in Puzzles you stick to the coordinate system of your modelling suite.

Puzzles axis.png

In case if you load scenes made in different modelling suites (for example if you run Verge3D Ultimate), we use the coordinate system of the scene which is loaded first.

Coordinate System Conventions

Software / Standard Default System Handedness Notes
3ds Max Z-up right-handed
Blender Z-up right-handed
Bullet/Ammo.js Y-up right-handed
Cinema4D Y-up left-handed
DirectX Y-up left-handed
Houdini Y-up right-handed
Maya Y-up right-handed configurable to Z-up right-handed
OpenGL/WebGL/glTF Y-up right-handed
Unity Y-up left-handed
Unreal Engine Z-up left-handed
Verge3D Y-up right-handed