[Openal-devel] Transformation by matrices

[Alexandre Mah]

On 20/04/2005, at 2:06 PM, Alexandre Mah wrote:

> This would also greatly help OpenAL's integration with OpenGL, since 
> you could then just simply query OpenGL's GL_MODELVIEW matrix, then 
> call alLoadMatrix(), and thereafter be able to use the exact same 
> positional data from OpenGL in OpenAL.

This is just a correction to my previous email.

Actually, OpenGL's GL_MODELVIEW matrix corresponds to just the OpenAL 
transformations involving AL_POSITION, AL_ORIENTATION, and any 
modelling transformations in OpenAL.
The transformations corresponding to AL_REFERENCE_DISTANCE and AL_GAIN 
may need to go into a separate matrix (perhaps something akin to 
OpenGL's GL_PROJECTION matrix), or alternatively simply have these 
transformations loaded into the AL_POSITION_TRANSFORM matrix before 
being multiplied by the GL_MODELVIEW matrix.

Currently, OpenGL can do things like recursive modelling (with its 
matrix support), which OpenAL cannot do easily.  I'd love to see OpenAL 
gain the ability to integrate nicely with OpenGL programs that do 
recursive modelling.