Re: "Most Wanted" list

[Frank C <li...@si...>]

On 2-Jun-04, at 2:15 PM, Joseph J. Strout wrote:

> 2. Color/alpha modulation on textured geometry.

Hmmm... There's a "TEMPORARY FIX" in ir_geom_trimesh_initialise that 
removes colour and transparency information from all trimeshes - 
specifically it notes:

	// If we are using a texture, pretend the vertices are opaque white.
	// This is to make it so that a textured TriMesh is affected by 
lighting,
	// but not by the color of the geometry.

Now the question is; what is this supposed to fix? If this code is 
removed, colour and transparency blends with textures (as they do in 
the tribuffer path) which is a desirable effect IMHO...

> QD3D does this when using the null shader; we should probably do the 
> same (and perhaps consider an object property later that extends this 
> behavior to phong/lambert-shaded objects).

Removing the "fix" above results in opposite behaviour to QD3D however 
- lit objects modulate colours, unlit objects don't - but this is due 
by the rather lazy way Quesa "disables" lighting on objects affected by 
null shaders. i.e. it doesn't, but instead uses the GL_REPLACE blend 
mode.

So what should be done here? This bug can basically be resolved by 
removing the "TEMPORARY FIX", but it won't match QD3D's behaviour - or 
- it can be left as is, and actually disable lights when rendering 
objects with a null shader while still modulating colours to match 
QD3D. The tribuffer path would need a similar fix to fully comply in 
this case.

Personally I'd like to see colours modulated _all_ the time - QD3D be 
damned! ;)

Frank.