Defines codes for culling algorithms that determine which triangles not to render when drawing triangle paths.
The terms POSITIVE
and NEGATIVE
refer to the
sign of a triangle's normal along the z-axis. The normal is a 3D vector
that is perpendicular to the surface of the triangle.
A triangle whose vertices 0, 1, and 2 are arranged in a clockwise order
has a positive normal value. That is, its normal points in a positive
z-axis direction, away from the current view point. When the
TriangleCulling.POSITIVE
algorithm is used, triangles with
positive normals are not rendered. Another term for this is backface
culling.
A triangle whose vertices are arranged in a counter-clockwise order has
a negative normal value. That is, its normal points in a negative z-axis
direction, toward the current view point. When the
TriangleCulling.NEGATIVE
algorithm is used, triangles with
negative normals will not be rendered.
Variables
inlineread onlyNEGATIVE:TriangleCulling = 0
Specifies culling of all triangles facing toward the current view point.
inlineread onlyNONE:TriangleCulling = 1
Specifies no culling. All triangles in the path are rendered.
inlineread onlyPOSITIVE:TriangleCulling = 2
Specifies culling of all triangles facing away from the current view point. This is also known as backface culling.