Am 10.10.2014 05:45, schrieb Bald Eagle:

> I was thinking about UV-mapping an SDL object with a ceiling medallion, but that
> turned out to be an exercise in mind-bending frustration.  So many mapping types
> and options and how to go about nesting what in what...
>
> Is there a complete list of the mapping types?  all I found was
>
> 2.7.4.2 Map type constants
> Plane_Map = 0
> Sphere_Map = 1
> Cylinder_Map = 2
> Torus_Map = 5
>
> But the docs say there is mapping for
> bicubic_patch, box, lathe, sor, mesh, mesh2, ovus, parametric, sphere, and
> torus.  What are the numerical constants for these?

These are two separate things:

(1) In POV-Ray, the concept of a texture is generally 3-dimensional; 
objects can be thought of as being cut out of a 3D material. This is 
also true when you use an image_map: The 2D texture is "extruded" into 
the 3rd dimension, normally using a simple orthographic projection. The 
map_type can be used to change this projection.

(2) UV-mapping takes a single slice of a (3D) texture, and maps it onto 
the surface of a given geometric primitive according to rules specific 
to that primitive. There is generally no way to change this mapping, 
unless the primitive explicitly allows to specify UV mapping coordinates 
(such as mesh or mesh2).

Normally, when you use UV-mapping, you specifiy map_type 0 (or no 
map_type at all, as it is the default), so that the texture slice taken 
for the UV mapping is identical with the original image.

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