Rollover image for wireframe
This tutorial is a breakdown of the workflow required to convert an interior scene that has been setup for another renderer for rendering with MtoA. Scene setup and rendering should take no longer than an hour. The scene used in this example is part of this collection of architectural interiors.
Another tutorial that demonstrates different ways to approach lighting a room can be found here.
The workflow covers the following topics:
The scene has been exported from 3ds Max as an .fbx file and imported into Maya using the FBX plugin.
Scene lit with light portals (with Skydome light) outside of the windows and a Directional light representing sunlight
To preview how the lighting will affect the scene, you can apply a default Standard Surface shader override to the scene. This effectively creates a 'chalk preview' of your render and allows you to focus purely on lighting without being concerned about shading. Alternatively, there is a 'Lighting' mode in the Debug Shading in the Arnold RenderView window.
Reducing the Diffuse samples to 0 will effectively disable indirect lighting. This is useful when you want to test render direct lighting in the scene and will also be quicker to render.
The scene comes with default Phong shaders in Maya, visible in the Hypershade window. These need to be converted to Standard Surface shaders.
Default Maya scene with Maya Phong shaders visible in the Hypershade window
Select a Phong shader and open the Attribute Editor. Select Phong from the 'Type' scroll down menu and choose Standard Surface. Any diffuse color information will carry over to the Standard Surface shader.
If the Phong shader has textures assigned to the Color, these will automatically be connected to the Base Color of the Standard Surface shader, requiring no extra effort.
A shader conversion script is supplied with MtoA to facilitate the conversion of multiple shaders to Ai Standard.
Here, we will add some translucency to give the effect that the curtain is being lit from behind.
Rollover image to see the effect Thin Wall and SSS has on the curtain
Any glass surfaces will need to have 'Opaque' disabled. Otherwise, any shadows cast by the object will always be solid and not pick up the refraction color or density of the shader.
Ensure that the polygon face normals are all facing in the right direction (especially important when rendering glass surfaces with Arnold).
Opaque switch disabled for non-opaque surfaces such as glass