Contour Contrast Shaders
There are two built-in contour contrast shaders. Contour
contrast shaders specify where there should be a contour by
comparing the information stored by the contour store shader
during sampling. The two contour contrast shaders are designed to
be paired with the standard and simple contour store shaders
described above, respectively.
contour_contrast_function_levels
"contour_contrast_function_levels" (
scalar "zdelta",
scalar "ndelta",
boolean "diff_mat",
boolean "diff_label",
boolean "diff_index",
boolean "contrast",
integer "min_level",
integer "max_level"
)
- zdelta
- is the minimum depth difference required to
cause a contour, measured in coordinate units.
- ndelta
- is the minimum angle difference between normal
vectors required to cause a contour, measured in degrees.
- diff_mat
- if set to on, causes a contour
between different materials.
- diff_label
- if set to on, causes a contour
between different object labels. It can be used to outline
objects.
- diff_index
- if set to on, causes a contour
between different triangles. It can be used to draw triangle
wireframes.
- contrast
- if set to on, causes a contour
between colors that exceed the contrast threshold specified in
the options block. In the case of semitransparent object,
contrasts caused by other objects behind the semitransparent
object are taken into account.
- min_level
max_level - limit contours to ray
generations of at least min_level and at most max_level. Every
reflection and refraction counts as one level. For example, to
exclude contours around reflections and refractions, set
max_level to 0.
contour_contrast_function_levels_simple
This shader can be used for very fast contour computations
along with contour_store_function_simple if only the
outlines of objects need to have contours (and if they should
only have simple contours). This shader has no parameters.
contour_contrast_function_simple
"contour_contrast_function_simple" ()
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