There is only one view map per render layer. It controls the edge detection parameters.
- Control Mode
Which detected edges are actually rendered, and how, can be controlled either through:
- View Map Cache
An option to reuse a previously computed view map for subsequent rendering. The cache is automatically updated when the mesh geometry of the input 3D scene has been changed.
This functionality offers a major performance boost for Freestyle animation rendering when the camera-space mesh geometry is static, as well as for repeated still renders with updates of line stylization options.
Although the ’’View map cache’’ checkbox is a render layer option, the cache memory is shared by all render layers and scenes. This means that if Freestyle is used for two or more render layers (possibly in different scenes through the compositor), then the cached view map for one render layer is replaced by a new view map for another render layer and hence no performance gain is expected.
- Face Smoothness
When enabled, Smooth Shading will be taken into account for edges calculation.
- Crease Angle
If two adjacent faces form an angle less than the defined Crease Angle, the edge between them will be rendered when using Crease edge type selection in a line set. The value also affects Silhouette edge type selection.
Ignore the edges that are out of view. (Saves some processing time and memory, but may reduce the quality of the result in some cases).
Sphere Radius affects the calculation of curvatures for Ridge, Valley and Suggestive Contour edge type selection in a line set.
- Kr Derivative Epsilon
It provides you with control over the output of Suggestive Contour and Silhouette edge type selection (further information in this pdf).