View source for Diffusely convolved cube map

A ''diffusely convolved cube map'' is simply a blurred-down version of a regular [[CubeMap|cube map]]. When a [[:Category:Shaders|shader]] adds the cube map to the model's diffuse map the result is similar to global-illumination, except it is extremely efficient performance-wise. 

{|border="1"
|[[image:whatif_nmech_env-alone.jpg|thumb|left|The convolved cube map on a normalmapped model.]]
|[[image:whatif_nmech_env+lgt.jpg|thumb|left|The convolved cube map on a normalmapped model.]]
|-
|colspan="2"|Images by [http://www.linkedin.com/in/ericchadwick Eric Chadwick].
|}

== Lys ==
"Lys is an ultra-fast GPU powered solution that sets the standard for generating Radiance, Irradiance and Specular textures from panoramic, Sphere or 2d cube map cross source textures for use with HDR Image Based Lighting."

* [http://polycount.com/discussion/148953/lys-1-0-1-released Lys 1.0 Released!]

[[image:Lys_axis_rotation_3_855px.jpg|left|thumb|600px|Image by [http://www.metalliandy.com/ Andy "metalliandy Davies].]]<br clear="all"/>


== AMD Cubemapgen ==
* [http://code.google.com/p/cubemapgen/ Cubemapgen] is open-sourced utility for filtering down cube maps.
* Sébastien Lagarde made [http://seblagarde.wordpress.com/2012/06/10/amd-cubemapgen-for-physically-based-rendering/ a modified version for physically based rendering]

[[image:Cubemapgen_Tips.jpg|thumb|left|Some tips for filtering cubemaps in Cubemapgen. Image by [http://www.linkedin.com/in/ericchadwick Eric Chadwick].]]<br clear="all"/>


=== Cubemapgen Cube Faces ===
{| border="1" cellpadding="2" cellspacing="0"
|-
|  '''Cubemapgen''' 
|  '''3ds Max''' 
|  '''Maya''' 
|  '''CryENGINE 3''' 
|  '''Unity''' 
|-
|  +X 
|  _RT 
|  
|  
|  Left -X 
|-
|  -X 
|  _LF 
|  
|  
|  Right +X 
|-
|  +Y 
|  _UP 
|  
|  
|  Top +Y 
|-
|  -Y 
|  _DN 
|  
|  
|  Bottom -Y 
|-
|  +Z 
|  _BK 
|  
|  
|  Front (+Z) 
|-
|  -Z 
|  _FR 
|  
|  
|  Back (-Z) 
|}

{| border="1" cellpadding="2" cellspacing="0"
|-
|  '''Cubemapgen''' 
|  '''3ds Max''' 
|  '''Maya''' 
|  '''CryENGINE 3''' 
|  '''Unity''' 
|-
|  c00 
|  
|  
|  
|  Left -X (180°) 
|-
|  c01 
|  
|  
|  
|  Right +X (180°) 
|-
|  c02 
|  
|  
|  
|  Top +Y 
|-
|  c03 
|  
|  
|  
|  Bottom -Y 
|-
|  c04 
|  
|  
|  
|  Back -Z (180°) 
|-
|  c05 
|  
|  
|  
|  Front +Z (180°) 
|}

=== Cubemapgen Custom Meshes ===

{|border="1"
|[[image:cubemapgen_nmech_cube.jpg|thumb|left|Custom geometry in Cubemapgen.]]
|[[image:cubemapgen_nmech_basemap+cube.jpg|thumb|left|Basemap is modulated (multiplied) with the cube map.]]
|-
|colspan="2"|Images by [http://www.linkedin.com/in/ericchadwick Eric Chadwick].]]
|}

You can load your own geometry in Cubemapgen using the ''Load Object'' button, really helps to see what settings are working well. 

You can also load a bitmap for the model using the ''Load Basemap'' button. There's a bug right now that causes your Basemap to be mirrored vertically... to fix it pre-flip the bitmap yourself before loading it in Cubemapgen. An [[Ambient occlusion map]] map makes a great Basemap, or you can use your [[Diffuse map]].


== Editing Cubemaps in Photoshop ==
If your cube map is in DDS cube format, you'll need the NVIDIA DDS plugin to load and save in Photoshop.
* [http://developer.nvidia.com/nvidia-texture-tools-adobe-photoshop NVIDIA Photoshop Plugins]


== More Information ==
* [http://www.cgtextures.com/content.php?action=tutorial&name=cubemaps Cubemaps Tutorial] by CGTextures.com - Tutorial using Nvidia's Photoshop plugin, AMD's [http://developer.amd.com/gpu/cubemapgen/pages/default.aspx CubeMapGen], and Photoshop to convert cubemaps to various layouts.

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[[Category:TextureTypes]]