glPatchParameter — specifies the parameters for patch primitives
void glPatchParameteri( | GLenum pname, |
GLint value) ; |
void glPatchParameterfv( | GLenum pname, |
const GLfloat *values) ; |
pname
Specifies the name of the parameter to set. The symbolc constants GL_PATCH_VERTICES
, GL_PATCH_DEFAULT_OUTER_LEVEL
, and GL_PATCH_DEFAULT_INNER_LEVEL
are accepted.
value
Specifies the new value for the parameter given by pname
.
values
Specifies the address of an array containing the new values for the parameter given by pname
.
glPatchParameter
specifies the parameters that will be used for patch primitives. pname
specifies the parameter to modify and must be either GL_PATCH_VERTICES
, GL_PATCH_DEFAULT_OUTER_LEVEL
or GL_PATCH_DEFAULT_INNER_LEVEL
. For glPatchParameteri
, value
specifies the new value for the parameter specified by pname
. For glPatchParameterfv
, values
specifies the address of an array containing the new values for the parameter specified by pname
.
When pname
is GL_PATCH_VERTICES
, value
specifies the number of vertices that will be used to make up a single patch primitive. Patch primitives are consumed by the tessellation control shader (if present) and subsequently used for tessellation. When primitives are specified using glDrawArrays or a similar function, each patch will be made from parameter
control points, each represented by a vertex taken from the enabeld vertex arrays. parameter
must be greater than zero, and less than or equal to the value of GL_MAX_PATCH_VERTICES
.
When pname
is GL_PATCH_DEFAULT_OUTER_LEVEL
or GL_PATCH_DEFAULT_INNER_LEVEL
, values
contains the address of an array contiaining the default outer or inner tessellation levels, respectively, to be used when no tessellation control shader is present.
GL_INVALID_ENUM
is generated if pname
is not an accepted value.
GL_INVALID_VALUE
is generated if pname
is GL_PATCH_VERTICES
and value
is less than or equal to zero, or greater than the value of GL_MAX_PATCH_VERTICES
.
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 |
glPatchParameterfv | - | - | - | - | - | - | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ |
glPatchParameteri | - | - | - | - | - | - | ✔ | ✔ | ✔ | ✔ | ✔ | ✔ |
Copyright © 2010-2014 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. https://opencontent.org/openpub/.