Set default yaw axis Vector3::UNIT_Y (tabletop mode) + Optional X, Z and free rotation

[sercero]

This solves #18

[sercero]

Perhaps it would be better if this was an option... for me this is the most reasonable mode

[paroj]

I had this on initially. However, this assumes the model actually has y-up. If this is not the case, there is no way to properly orient the model.

An alternative would be to make this configurable:

• free rotation
• fixed x-up
• fixed y-up
• fixed z-up

[sercero]

Is there a way to detect if the model does not have Y-up and rotate everything?

Perhaps that would be faster.

In general one would open models that were exported for OGRE which is Y-up, so it makes sense that the default is this.

I think it would be easier to make this selectable and True by default.

If someone loads a model that is not Y-up (the rare case) then they can choose to disable this.

[paroj]

In general one would open models that were exported for OGRE which is Y-up, so it makes sense that the default is this.

like I described here OGRECave/blender2ogre#240 it is trivial for user code to change which axis is "up". So I would not assume Y-up.

Also, since assimp is used, you are not even limited to ogre specific files, but maybe just want to inspect how a .obj would look when imported directly in Ogre. There any up assumptions goes out of the window.

Is there a way to detect if the model does not have Y-up and rotate everything?

one could look at the extents, but you need to assume whether the object is a statue or a bench. so generally: no.

[sercero]

I had this on initially. However, this assumes the model actually has y-up. If this is not the case, there is no way to properly orient the model.

An alternative would be to make this configurable:

• free rotation
• fixed x-up
• fixed y-up
• fixed z-up

The issue is that currently you only have the options:

• free rotation
• fixed y-up

Otherwise a modification of OGRE Bites CameraMan would be needed.
Unless we can change this with setPivotOffset()

[paroj]

Otherwise a modification of OGRE Bites CameraMan would be needed.

you should be able to get there without touching CameraMan by just changing the camera node like:

https://github.com/OGRECave/ogre/blob/a98c9ee8a6b93f9cf2d0d1efdaf4e0b7002d3c74/Samples/Simple/include/BSP.h#L78-L79

[sercero]

Traceback (most recent call last):
  File "D:\OGRE2\Built\ogre-meshviewer_24.02-win64\ogre_mesh_viewer.py", line 714, in <module>
    app.initApp()
  File "D:\OGRE2\Built\ogre-meshviewer_24.02-win64\ogre_mesh_viewer.py", line 680, in setup
    camnode.setFixedYawAxis(True, Ogre.Vector3.UNIT_Z);
AttributeError: type object 'Ogre.Ogre.Vector3' has no attribute 'UNIT_Z'

Can you help with this?

I can use (0,0,1) but UNIT_Z would be better.

[paroj]

use (0,0,1).
Maintaining UNIT_Z is a PITA, as Vector3 is a typdef of Vector<N, float> and it only makes sense for N==3

[paroj]

this method only modifes self.app therefore it should be moved to app, like probably all related fields

[sercero]