[X3D-Public] help w/ X3DOM cube map and refraction/reflection

[Michalis Kamburelis]

John Carlson wrote:
> Can someone help me get this X3DOM code into a cube map and using
> refraction/reflection?  Thanks!

Maybe some general notes regarding cube maps and X3D, and how they work 
in my engine and view3dscene, will help. What I write below doesn't 
(necessarily) apply to X3DOM, so I don't know how much it will be useful 
for you, but here goes...

The standard way to use cube maps and reflections is to use one of the 
XxxCubeMapTexture nodes (see 
http://www.web3d.org/files/specifications/19775-1/V3.2/Part01/components/env_texture.html 
) and use texture coordinate generator on your shape. Standard X3D 
provides you TextureCoordinateGenerator with 
mode="CAMERASPACEREFLECTIONVECTOR" (see 
http://www.web3d.org/files/specifications/19775-1/V3.2/Part01/components/texturing.html#TextureCoordinateGenerator 
) which is almost, but not quite correct, a way to get mirrors, by a 
code like

Shape {
   appearance Appearance {
     material Material { }
     texture GeneratedCubeMapTexture {
       update "ALWAYS"
       size 512
     }
   }
   geometry IndexedFaceSet {
     texCoord TextureCoordinateGenerator { mode 
"CAMERASPACEREFLECTIONVECTOR" }
     # ... other IndexedFaceSet fields
   }
}

My engine and view3dscene give you two extensions to make this really work:

- texCoord field is available for all geometry nodes (not just for a few 
chosen ones), so it's also available for primitives like Sphere, Box, 
and our Teapot.

- TextureCoordinateGenerator with mode="WORLDSPACEREFLECTIONVECTOR" is 
available. This makes a truly correct reflection.

See 
http://castle-engine.sourceforge.net/x3d_implementation_cubemaptexturing.php 
, in particular section "Tutorial: How to make a mirror" there, for 
pointers how to make reflections easy with cube maps. You can test them 
with view3dscene (http://castle-engine.sourceforge.net/view3dscene.php ) 
on demo models (http://castle-engine.sourceforge.net/demo_models.php ), 
there are examples in demo_models/cube_environment_mapping/ showing cube 
maps and reflections. There are also examples in demo_models/water/ 
showing how to use GLSL shaders (also with the help of some of my 
extensions, for GLSL Effects) to get water, with reflections and 
refractions by cube maps.

Hope this helps :),
Michalis