org.lwjgl.opengl

Class ARBPolygonOffsetClamp

java.lang.Object

org.lwjgl.opengl.ARBPolygonOffsetClamp

public class ARBPolygonOffsetClamp
extends java.lang.Object

Native bindings to the ARB_polygon_offset_clamp extension.

This extension adds a new parameter to the polygon offset function that clamps the calculated offset to a minimum or maximum value. The clamping functionality is useful when polygons are nearly parallel to the view direction because their high slopes can result in arbitrarily large polygon offsets. In the particular case of shadow mapping, the lack of clamping can produce the appearance of unwanted holes when the shadow casting polygons are offset beyond the shadow receiving polygons, and this problem can be alleviated by enforcing a maximum offset value.

Requires OpenGL 3.3.

Field Summary

Fields

Modifier and Type	Field and Description
static int	GL_POLYGON_OFFSET_CLAMP Accepted by the pname parameters of GetBooleanv, GetIntegerv, GetInteger64v, GetFloatv, and GetDoublev.

Method Summary

Modifier and Type	Method and Description
static void	glPolygonOffsetClamp(float factor, float units, float clamp) The depth values of all fragments generated by the rasterization of a polygon may be offset by a single value that is computed for that polygon.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

GL_POLYGON_OFFSET_CLAMP

public static final int GL_POLYGON_OFFSET_CLAMP

Accepted by the pname parameters of GetBooleanv, GetIntegerv, GetInteger64v, GetFloatv, and GetDoublev.

See Also:

Constant Field Values

Method Detail

glPolygonOffsetClamp

public static void glPolygonOffsetClamp(float factor,
                                        float units,
                                        float clamp)

The depth values of all fragments generated by the rasterization of a polygon may be offset by a single value that is computed for that polygon. This function determines this value.

factor scales the maximum depth slope of the polygon, and units scales an implementation-dependent constant that relates to the usable resolution of the depth buffer. The resulting values are summed to produce the polygon offset value, which may then be clamped to a minimum or maximum value specified by clamp.

The values factor, units, and clamp may each be positive, negative, or zero. Calling the command PolygonOffset is equivalent to calling the command PolygonOffsetClamp with clamp equal to zero.

Parameters:

factor - scales the maximum depth slope of the polygon

units - scales an implementation-dependent constant that relates to the usable resolution of the depth buffer

clamp - the minimum or maximum polygon offset value