[Bf-taskforce25] Texture workflow update

[William Reynish]

Hi All,

The material/texturing workflow is already being tweaked a bit for  
2.5. Previously this has been one of Blender's weak areas, so a little  
optimizing will do good.

The first thing I'd like to mention, and this is something that has  
already been done, is that all texture settings have been moved  
together, inside the textures tab. This means far less jumping back  
and forth between material and texture panels while tweaking textures.  
Of course at the moment this also means you can't see a preview of the  
final material while tweaking influence settings, but this can be  
overcome by improving the texture preview widget like so:

http://www.reynish.com/files/blender25/texturepreview.png

The second thing that could be improved is how the texture influence  
controls work. Currently some influence settings have a slider that  
controls the intensity of that parameter; others share a single  
slider. This is both confusing and inflexible. Though if all those  
settings had its own slider the influence panel would quickly get  
rather large. A solution to this problem is to simply remove all the  
checkboxes, and only have sliders, like so:

http://www.reynish.com/files/blender25/textureinfluence.png

This also solves the issue of the old tripple-state checkboxes for  
inverting values. These sliders can simply have negative values for  
inverting the effect.

Using sliders only also means there is space to add more influence  
parameters in the future, to be able to influence, say, SSS settings.

Lastly I've been thinking about ways to make the texture tab more  
clear in what it relates to. Textures can affect both world, lamp and  
materials, and you can get to each texture area by cycling through the  
texture display buttons to go from world to lamp to materials.

This can really be cleared up so that we actually have three texture  
tabs, one for each ID type that uses them. Instead of polluting the  
main header buttons with too many tabs though, they can be tucked away  
inside each ID tab, like so:

http://www.reynish.com/files/blender25/texturetabs.png

These sub-tabs can nicely be used for other things too, like a game  
tab with two sub-categories for controlling scene-specific game  
settings and object-specific game settings.

Cheers,

-William