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/** Turn our mesh into a subdivision surface */
nsi.SetAttribute( "simple polygon",
NSI::CStringPArg("subdivision.scheme", "catmull-clark") ); |
...
Transforming Geometry
In NSI, a geometry is only considered if connected to the scene root (which has the special handle ".root"). It is possible to directly connect a geometry node (such as the simple polygon above) to scene's root but it wouldn't be very useful. It is common to place geometry using a transform and NSI has a special node for it.
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|
nsi.Create( "translation", "transform" );
nsi.Connect( "translation", NSI_SCENE_ROOT );
nsi.Connect( "simple polygon", "", "translation", "objects" );
double trs[16] =
{
1., 0., 0., 0.,
0., 1., 0., 0.,
0., 0., 1., 0.,
0., 1., 0., 1. /* transalte 1 unit in Y */
};
nsi.SetAttribute( "translation",
NSI::DoubleMatrixArg("transformationmatrix", trs) ); |
Assigning Shaders
Shaders are created as any other nodes using the NSICreate API call. They are not assigned directly on geometry but through an intermediate attributes nodes. Having an extra indirection allows for more flexible export as we will see in the following chapters.
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/**
Create a simple shader node using the standard OSL "emitter" shader.
Set it's parameter to something different than defaults.
*/
nsi.Create( "simpleshader", "shader" );
float red[3] = {1,0,0};
nsi.SetAttribute( "simpleshader",
(
NSI::CStringPArg("shaderfilename", "emitter"),
NSI::ColorArg( "Cs", red),
NSI::FloatArg( "power", 4.f )
) );
/** Create an attributes nodes and connect our shader to it */
nsi.Create( "attr", "attributes" );
nsi.Connect( "simpleshader", "", "attr", "surfaceshader" );
/* Connecting the attributes node to the mesh assign completes the assignment */
nsi.Connect( "attr", "", "simple mesh", "geometryattributes" ); |
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