2017

See Specular Highlights (page 538).
Lighting box Select Ambient or Diffuse lighting so that the surface can reflect incidental light.
See Incidental Light Reflection (page 539).
Surface Section
Shape box Select a shape for the selected surface. For Stereo Objects, you are limited to using a Flat surface.
For shapes other than flat, you have access to the Vertices and UV Points settings.
DescriptionShape
This is the simplest surface. It is added to the scene by default the first time you enter Action with a Front,
Back, and Matte. When working with a Stereo Object, Flat is the only shape available. You cannot change
Flat
its shape because a flat image does not have vertices. You can, however, scale and shear a flat image using
its axis.
A bilinear surface has four vertices: one for each corner. The vertices are joined using linear interpolation
(straight lines). You can animate the shape of a bilinear surface by changing the position of the corners.
Bilinear
An extended bicubic surface has vertices in sections that can be subdivided up to eight times to increase
the number of vertices. The vertices are joined using bicubic interpolation (curved lines). You can animate
Extended Bicubic
the shape of a bicubic surface by changing the position of the corners and moving the tangent handles
to adjust the curve between corners.
Flip Normals button Enable to flip the selected surface normals to light the back side of a surface.
Force 2-Sided button Enable to have lights in the scene light both sides of the surface (when shading is
turned on).
Surface Offset X field Displays the level of offset for a surface along the X axis. Editable.
Surface Offset Y field Displays the level of offset for a surface along the Y axis. Editable.
See
Offsetting a Surface (page 510).
Shadow Casting box Select how the selected image object will be affected by a Shadow Cast object in the
scene.
See
Surface and Geometry Shadow Casters (page 543).
Extrapolation Section
Using the extrapolation sliders, you can extrapolate the texture beyond the geometry, in X and Y. You can
assign negative extrapolation values and effectively crop the texture. The extrapolation is in mirror mode,
by default. You can change this by adding a Diffuse node in the Action schematic. When working with an
Extended Bicubic surface, you can choose between Linear Extrapolation and Smooth Extrapolation. Smooth
extrapolation produces a more organic deformation, extrapolating the deformation created by the vertices
and tangents, while Linear extrapolates the surface in a straight line after the last vertices, in the direction
of the tangents.
502 | Chapter 15 Compositing in 3D Space with Action