glPolygonOffset — set the scale and units used to calculate depth values
void glPolygonOffset(
|
GLfloat factor, |
GLfloat units); |
factor
Specifies a scale factor that is used to create a variable depth offset for each polygon. The initial value is 0.
units
Is multiplied by an implementation-specific value to create a constant depth offset. The initial value is 0.
When GL_POLYGON_OFFSET_FILL, GL_POLYGON_OFFSET_LINE, or
GL_POLYGON_OFFSET_POINT 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
glPolygonOffset is useful for rendering hidden-line images, for applying decals
to surfaces, and for rendering solids with highlighted edges.
glIsEnabled with argument
GL_POLYGON_OFFSET_FILL,
GL_POLYGON_OFFSET_LINE,
or GL_POLYGON_OFFSET_POINT.
glGet with argument GL_POLYGON_OFFSET_FACTOR or
GL_POLYGON_OFFSET_UNITS.
| OpenGL Version | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Function / Feature Name | 2.0 | 2.1 | 3.0 | 3.1 | 3.2 | 3.3 | 4.0 | 4.1 | 4.2 | 4.3 | 4.4 | 4.5 |
glPolygonOffset
|
✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ |
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