VRayCurvature is a texture that will effectively sample the underlying mesh for curves. A region around each shaded point gets sampled with additional rays (similar to VRayDirt) and all additional normals are averaged to get a smooth normal at the original point. This normal is used to compute the color. The color at each shaded point is a greyscale value: darker values are dents (or holes), lighter values are peaks, which depends on the Mode of the map. The parameters should be adjusted by trail trial and error since they generally depend on the scale used, hence the defaults might not be appropriate at all in some cases.
Legacy - This mode does not distinguish if the mesh is curving outward or inward but instead only the amount of curvature overall. Convex - Generates a grayscale based on the mesh's outward curve. Concave - Generates a grayscale based on the mesh's inward curve. Both - Generates a red-green gradient based on both the mesh's convex and concave. Red corresponds to the mesh's convex and green corresponds to the mesh's concave.
Subdivs – Controls the number of samples around each shaded point.
Sample spread – Spread – Controls the radius of the sampled region.
Min/Max Output Color – An option to map the output colors to a range other than 0..1.Makes the output texture darker or lighter.
Scale – Adjusts the scale relative to which the curvature is measured.
Ignore Bump - When enabled, excludes Bump maps from VRayCurvature computations.
Min Output Color - Sets the value of the output amount at the bottom of the grayscale ramp (that covers dents in the mesh). Default value is 0 - completely black.
Max Output Color - Sets the value of the output amount at the top of the grayscale ramp (that covers peaks in the mesh). Default value is 1.
Output Color Gain - Multiplies the output values.
Output Color Lift - Uniformly lightens the output values.
Output Color Gamma - Applies gamma correction to the output values.
Output Color Pivot - Pivots the value to the gamma correction (output values equal to the pivot value are left unchanged).
Output Color Clamp - When enabled clamps the MinOutputcolor and Max Outputcolor values in [0,1] range (negative values are output as 0 and values above 1 are being output as 1)
Scale - Factor determining the scale that the curvature traces. Can be used to match curvature between big and small objects.
Threshold - Controls the amount of the sampled areaThreshold – Curvature values below this threshold are ignored and are shown as pure black. This focuses the curvature effect only around the most curved areas of the mesh.
