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GL
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Method GL.glPolygonOffset()
- Method
glPolygonOffset
void glPolygonOffset(float factor, float units) - Description
When GL_POLYGON_OFFSET is enabled, each
fragment's depth value will be offset after it is interpolated
from the depth values of the appropriate vertices.
The value of the offset is "factor" ~*~ DZ ~~+~~ r ~*~ "units",
where DZ~ is a measurement of the change in depth relative to the screen
area of the polygon, and r is the smallest value that is guaranteed to
produce a resolvable offset for a given implementation.
The offset is added before the depth test is performed and before
the value is written into the depth buffer.
glPolygonOffset is useful for rendering hidden-line images, for applying decals
to surfaces, and for rendering solids with highlighted edges.
- Parameter factor
Specifies a scale factor that is used to create a variable
depth offset for each polygon. The initial value is 0.
- Parameter units
Is multiplied by an implementation-specific value to
create a constant depth offset. The initial value is 0.
- Throws
GL_INVALID_OPERATION is generated if glPolygonOffset is executed
between the execution of glBegin and the corresponding
execution of glEnd .
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GL.glPolygonMode()