SkIndigo 1.0.1 

Freeware SketchUp Exporter to Indigo 1.0.1
Author: Whaat

Based on SU2KT written by Tomasz
SU2POV written by Didier Bur
and OGRE exporter by Kojack

Please see Indigo's website if you have questions about Indigo.
http://www.indigorenderer.com

Open SkIndigo.rb to view the changelog.

INSTALLATION
1. Copy SkIndigo.rb into your SketchUp/Plugins directory
2. Copy the SkIndigo folder into your SketchUp/Plugins directory
3. Copy the previews folder into your Indigo directory
4. Remove any previous versions of SkIndigo from your SketchUp/Plugins directory

HOW TO:

Render with Sun and Sky Light
1. Turn on Sun and Sky in SkIndigo Render Settings
2. Use SketchUp shadow settings to control the sun direction.

Render with Custom Lights
1. Use either an RGB Light or a Blackbody Light material in your scene.
2. RGB lights will emit light according to the material color
3. Blackbody lights will emit light according to the temperature
4. Light is only emitted from the front side of the face
5. If the material has a texture, the texture will control the color of the light

Render with Uniform Background Light
1. Turn on Background in SkIndigo Render Settings
2. Scene will be lit with a uniform background light matching the current SketchUp background color

Render with Environment Map
1. Turn on Environment Map in SkIndigo Render Settings
2. Set your Environment Map using the SkIndigo menu item
3. You can use EXR maps in Lat_Long format or FLOAT maps in Spherical format
4. HDR maps are not currently supported by Indigo.
5. The position of the environment map cannot be adjusted in Indigo.  The y-axis points to the center of the environment map.

Monochrome Render (Clay)
1. Change SketchUp face style mode to monochrome
2. Choose Clay to render clay mode or any other material
3. Choose Default to render using the current default material color

Adjust the Rendered Image Tones and Exposure
1. Make sure you have downloaded the Indigo Tonemapper application from the Indigo website.
2. Turn on Save IGI in SkIndigo Render settings before you render.
3. IGI files will automatically be saved into the Indigo/render directory.
4. Load the appropriate IGI file using the Indigo Tonemapper application.

Create Transparent Material
1. Enable transparency in SketchUp material settings using the opacity slider
2. Set the material type to SPECULAR
3. The opacity slider will change the amount of RGB absorptivity. Set to 0 for no absorptivity (i.e. clear glass).
4. SPECULAR materials should have thickness to render properly.

Create Material with Specular Highlights 
1. Set the material type to Phong
2. Set the index of refraction to >1.0 (High IOR=Very reflective)
3. Use the exponent value to control the glossiness. (High value=Smooth polished surface)

Create Diffuse (Lambertian) Material
1. Set the material type to Diffuse

Create Diffuse Transmitter Material
1. Set the material type to Diffuse
2. Use the SketchUp opacity slider to set the relative amount of transmittance and reflectance.  (Set opacity to 0 for pure diffuse transmitter)

Use BLEND materials
1. Set the material type to BLEND
2. If a texture is applied to the material, it will be used as the blend map or mask
3. If no texture is applied, the blend factor will control the weight of the materials

Use Sub-surface scattering
1. Set the material type to SPECULAR or GLOSSY TRANSPARENT
2. Enable SSS with the material editor
5. Input the Uniform scattering coefficient or the 3 RGB scattering coefficients separated by spaces
6. SPECULAR materials should have thickness to render properly
7. The opacity slider will change the amount of RGB absorptivity. Set to 0 for no absorptivity

Use Exit Portals
1. Set the material type to EXIT PORTAL
2. The front side of the face must point inwards
3. The exit portal should cover all openings to the environment where you want light to enter

Use Thin Glass
1. Set the material type to THIN GLASS.  This is not a native Indigo material type
2. Thin Glass materials are exported as a blend between a null material and a high IOR material
3. The SketchUp opacity slider controls the blend factor.  An opacity value of 20 is recommended for plane glass windows.

Use Material Presets
1. Presets are intended to give you approximate starting values that you can further refine to suit your needs
2. These values will be updated in future releases as the Indigo material library continues to be developed

Use Textures
1. Apply textures directly to individual faces, not groups or components
2. Distorted textures (eg. projected from Photomatch) should be exploded (SkIndigo UV mapping context menu) in order to render properly.
3. Only 3 component JPEG and PNG textures are supported but PNG may cause Indigo to crash.  Grayscale textures are not supported.

Use Bump, Exponent, and Clip Maps
1. You can select any texture that is currently in your model
2. The map will be positioned using the same coordinates as the currently applied Sketchup texture.  If no Sketchup texture is applied, you must save the UVs using SkIndigo UV mapping
3. See below for help with SkIndigo UV mapping
4. Set bump or exponent gain

Use Fog Export
1. Enable Fog display within Sketchup
2. Set the left fog slider to 0
3. Set the right fog slider to the distance that an object will be hidden by fog
4. Fog increases render times substantially

Use Instancing
1. Right-click on any component to enable or disable instancing
2. Components that contain Blackbody, RGB light materials or Exit Portals cannot be instanced
3. Face-me components cannot be inside instances
4. Indigo Spheres cannot be inside instances

Use Indigo Sphere Primitives
1. Any component definition that is named IndigoSphere will be exported as an Indigo sphere primitive
2. The size of the sphere is based on the maximum dimension of the component's bounding box
3. An Indigo Sphere will use the material that is applied to the component instance.

Use UV Mapping
1. Load all entities that have a particular material applied
2. Use the Sketchup position texture tool to position the texture or the Paint Bucket to change the dimensions of the texture
3. Save the current UV set (texture position) to an index
4. Switch all loaded entities to a different material (eg. bump map material)
5. Re-position the newly applied texture as before
6. Save the current UV set to a different index than step 3
7. Repeat steps 4-6 if desired (maximum of 4 UV sets)
8. Switch back to the original material
9. Assign the appropriate UV sets to the original material using the material editor.

Use Dummy Components
1. Create a new component that has the same size and the same axis location as the one you are wanting to substitute
2. Name the new component definition "name_dummy" where "name" is the name of the component that the dummy represents.
3. If you want to enable instancing for this component, make sure that you enable instancing for the dummy, not the original component

Resume a Render from an .igi file
1. From the Ruby Console Window type "Indigo.res"
2. Locate the Indigo IGI file and then the Indigo IGS input file.

TIPS:

1. Be sure that no faces are reversed.  Use monochrome mode to check for reversed faces
2. Use layers to separate geometry and lights.  For example, put different lighting set-ups on different layers  
3. If you are getting strange shadows in your render, try disabling smoothing.  Also, check orientation of faces

Indigo features currently not supported:
1. Peak spectra
3. Dermis and epidermis media
4. a and c texture coefficients

KNOWN ISSUES/BUGS:
1. Indigo sphere primitives cannot be inside instances
2. Meshlights and Exit Portals cannot be inside instances 
3. Face-me components cannot be inside instances
4. Sun direction does not export correctly if model is geo-located
5. Textures applied to groups and components not supported.  Textures should be applied at face level.
6. UV sets fail to load for some faces
7. UV sets fail to load properly after transforming geometry

