Class EXTPolygonOffsetClamp

java.lang.Object
org.lwjgl.opengl.EXTPolygonOffsetClamp

public class EXTPolygonOffsetClamp extends Object
Native bindings to the EXT_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
    Description
    static final int
    Accepted by the pname parameters of GetBooleanv, GetIntegerv, GetInteger64v, GetFloatv, and GetDoublev.
  • Method Summary

    Modifier and Type
    Method
    Description
    static void
    glPolygonOffsetClampEXT(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 Details

    • GL_POLYGON_OFFSET_CLAMP_EXT

      public static final int GL_POLYGON_OFFSET_CLAMP_EXT
      Accepted by the pname parameters of GetBooleanv, GetIntegerv, GetInteger64v, GetFloatv, and GetDoublev.
      See Also:
  • Method Details

    • glPolygonOffsetClampEXT

      public static void glPolygonOffsetClampEXT(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. The function that determines this value is specified with this command.

      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 PolygonOffsetClampEXT 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 clamp value