LDA (Length/Distance/Angle) Approximation
The LDA approximation method is a curvature-dependent approximation based on subdivisions by length, distance, and angle. This type of approximation uses adaptive sampling between parametric intervals.
Length subdivides the surface or curve so that no edge length of the tessellation (object coordinates) exceeds the Length parameter. Length is given as a distance in camera space or as a fraction of a pixel diagonal in raster space (View Dependent). Small values such as 1 are recommended. Length is affected by the Min and Max Subdivision parameters.
Distance specifies the maximum distance between the tessellation and the actual curve or surface. The value is a distance in camera space, or a fraction of a pixel diagonal in raster space. As a starting point, a small distance such as 0.1 is recommended. Distance is affected by the Min and Max Subdivision parameters.
Angle specifies the maximum angle in degrees between normals of adjacent tiles of a displaced polygon, the tessellation of a surface, or its displacement, or between tangents of adjacent segments of the curve approximation. Large angles such as 45 degrees are recommended. Angle is affected by the Min and Max Subdivision parameters.
When using two or more of the LDA approximation types together (length and distance, for example), you can specify when the approximation settings should stop tessellating the approximated object(s). Choose one of the following settings:
• Length, Distance and Angle: Tessellation continues until the Length, Distance, and Angle requirements have all been met.
• Length, Distance or Angle: Tessellation stops when either the Length, Distance, or Angle requirement has been met.
Autodesk Softimage v.7.5