Optional Capabilities
The RenderMan Interface Specification 3.1 identified certain capabilities
which a renderer could choose to implement or not to implement and still
be called compliant.. The following list summarizes RenderDotC's
features in terms of these optional capabilities.
Solid Modeling
The Solid Modeling optional capability is not implemented. All primitives
are rendered as a collection of surfaces. The spatial set operators
are ignored.
Trim Curves
The Trim Curve optional capability is fully implemented. Note that
the curve orientation rule mentioned in the specification need not be followed
(i.e. the curve may go clockwise or counter-clockwise). Only the
odd winding rule and the trim curve "sense" define which part is inside
and which is outside.
Level of Detail
The Level of Detail optional capability is fully implemented.
Motion Blur
The Motion Blur optional capability is partially implemented. Only linear
blur between the shutter open and close times specified in RiShutter()
is supported. Times passed to RiMotionBegin that do not fall between
shutter open and close times result in the motion being clamped for the
duration of the difference. If more than two keyframes are specified
between RiMotionBegin and RiMotionEnd, then only the first and last ones
are used. Any transformation may be used when doing transformational motion
blur. All primitives correctly do deformational motion blur.
Shading is done at shutter open time only. Shading parameters do
not motion blur. Shutter open time is passed to shaders as the shading
global "time".
Depth of Field
The Depth of Field optional capability is fully implemented.
Programmable Shading
The Programmable Shading optional capability is partially implemented.
Users may write surface, light, volume and displacement shaders in RenderMan
Shading Language. Imager and deformation shaders are not supported.
Special Camera Projections
The Special Camera Projections optional capability is not implemented.
Only the required orthographic and perspective camera projections are allowed.
Deformations
The Deformations optional capability is not implemented. Deformation
shaders are ignored.
Displacements
The Displacements optional capability is fully implemented.
Spectral Colors
The Spectral Colors optional capability is not implemented. Multiple component
colors are accepted, but are immediately converted to RGB color space for
internal calculations. Note that RiColorSamples works correctly.
Texture Mapping
The Texture Mapping optional capability is fully implemented.
Environment Mapping
The Environment Mapping optional capability is fully implemented.
Bump Mapping
The Bump Mapping optional capability is not implemented. The bump() function
always returns [0.0 0.0 0.0]. RiMakeBump() does nothing.
Shadow Depth Mapping
The Shadow Depth Mapping optional capability is fully implemented.
Volume Shading
The Volume Shading optional capability is partially implemented. Atmosphere
shaders work correctly. Interior and exterior shaders are ignored. The
incident() and opposite() functions return 0.0.
Ray Tracing
The Ray Tracing optional capability is not implemented. The trace()
function returns [0.0 0.0 0.0].
Radiosity
The Radiosity optional capability is not implemented.
Area Light Sources
The Area Light Source optional capability is not implemented. RiAreaLightSource()
is equivalent to RiLightSource().
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