Static Sub ShadeModel ( Model As Integer )
flat or smooth shading.
Specifies a symbolic value representing a shading technique.
Accepted values are Gl.FLAT and Gl.SMOOTH.
The initial value is Gl.SMOOTH.
GL primitives can have either flat or smooth shading.
causes the computed colors of vertices to be interpolated as the
primitive is rasterized,
typically assigning different colors to each resulting pixel fragment.
Flat shading selects the computed color of just one vertex
and assigns it to all the pixel fragments
generated by rasterizing a single primitive.
In either case, the computed color of a vertex is the result of
lighting if lighting is enabled,
or it is the current color at the time the vertex was specified if
lighting is disabled.
Flat and smooth shading are indistinguishable for points.
Starting when Gl.Begin is issued and counting vertices and
primitives from 1, the GL gives each flat-shaded line segment
computed color of vertex
its second vertex.
Counting similarly from 1,
the GL gives each flat-shaded polygon the computed color of the vertex listed
in the following table.
This is the last vertex to specify the polygon in all cases except single
where the first vertex specifies the flat-shaded color.
Primitive Type of Polygon
Flat and smooth shading are specified by Gl.ShadeModel
and Gl.SMOOTH, respectively.
Gl.INVALID_ENUM is generated if mode
is any value other than
Gl.INVALID_OPERATION is generated if Gl.ShadeModel
is executed between the execution of Gl.Begin
and the corresponding execution of Gl.End.
with argument Gl.SHADE_MODEL
See original documentation on OpenGL website