Making Toon usable

[JenusL]

So this went a little further than expected... Instead of making a special case for the Toon shader I went with a more generic implementation. It's broken up in to two things, the ShaderDef building and the Parameter loading.

ShaderDef part Looking at camera_projection I noticed that it had a soft.node_type STRING "camera" line. I guessed it's to tell what type of objects to show in the pick browser but the soft.node_type has never been implemented in ShaderDef. So I went ahead and implemented that. It works like this: AI_TYPE_NODE will get pickers by default (just like before so this isn't new) AI_TYPE_STRING that has the soft.node_type attribute will get a Picker instead of a string field. I implemented all the filters in siShaderReferenceFilterType If array is added as a second word after the filter type, a ShaderArrayParamDef will be created instead of standard ShaderParamDef. The metadata for lights and rim_light of the toon shader looks like this.

[attr lights]
soft.label STRING "Lights"
soft.node_type STRING "light array"

[attr rim_light]
soft.label STRING "Light"
soft.node_type STRING "light"

And the Shader UI ends up like this:

Parameter Loading Parameter loading does two new things:

• If the shader input is AI_TYPE_STRING and the parameter is a Picker, do a name translation.
• If the parameter is a ShaderArrayParameter but the shader input is AI_TYPE_STRING, loop through the Array items and build a semicolon separated string of translated names.

Other changes

• Increased hardmax on output_filter_width from 10 to 100 so one can use thick lines when using contour filter.
• Added diffuse and specular of toon shader to viewport.
• Added test 0267 for Toon shader that covers light picking/translation, gradient tone mapping and stylized highlight.

This passes the testsuite and closes #24