[Radiance-general] Various texture mappings at rendertime

[Dion Moult]

Good day all, 
I've got a few questions about texture mappings which are so prevalent in other less validated rendering engines. I understand that these texture mappings aren't usually in the Radiance vocabulary as usually simple materials, or even greyscale materials with a focus purely on luminance is used. But hey :) 
Displacement maps:

Some other rendering engines (which may not be scientifically validated, such as Pixar's Renderman) support a form of displacement mapping that is applied at render time. That is, the lower resolution mesh is fed into the rendering engine along with a bitmap that represents a height map, which is then used to displace the mesh. 
Please note that this is not the same as a normal map / bump map, which simply perturbs the surface normals but does not actually shift the geometry itself. 
Is this possible in Radiance?
Normal maps:
As a side question, I encountered the original discussion about bump mapping / normal mapping by Simon and Greg back in 1992 about using texdata along with a custom script to create the data files. I've recreated this method successfully but am curious as to whether there is something now more built-in :) (yes, I saw the texpict patch but it is now outdated) Is there?
Occlusion maps:
From my understanding, the usage of occlusion maps to express ambient occlusion is not a thing in Radiance.  Although it is perhaps technically possible to achieve, it only serves to create artificial peak thresholds of the Rgb reflectance values that is ignorant of the actual lighting being used in the scene. Instead, the occlusion should be calculated by Radiance itself by nature of less bounces near corners. Is this understanding correct? If so, I am curious why it is so popular in other "photorealistic" rendering engines. 
Diffuse maps:
This is basically colorpict in action. From my understanding, there is no problem in using this to add further realism and rgb relevant analysis to the Radiance render as long as the picture used has pixels that aren't merely artistic, but actually do represent the Rgb reflectance values of the material. Where can I learn more about how to create and find repositories of these types of pictures? I am cautious that if I simply use any old picture online, it may incorrectly skew the luminance analysis. 
UV mapping with coordinates:
I played a bit with maps and got familiar with the various transforms, pic_u/v and tile_u/v options to place the maps to scale. At first glance I did not notice anything in the refman about using more sophisticated UV coordinates (for example, map UV coordinates directly to coordinates in a polygon) Is this possible? 
Sorry for the barrage of questions. 
Kind regards, Dion
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