Name

glGetVertexAttrib — Return a generic vertex attribute parameter

C Specification

void glGetVertexAttribfv(GLuint index,
 GLenum pname,
 GLfloat *params);
 
void glGetVertexAttribiv(GLuint index,
 GLenum pname,
 GLint *params);
 
void glGetVertexAttribIiv(GLuint index,
 GLenum pname,
 GLint *params);
 
void glGetVertexAttribIuiv(GLuint index,
 GLenum pname,
 GLuint *params);
 

Parameters

index

Specifies the generic vertex attribute parameter to be queried.

pname

Specifies the symbolic name of the vertex attribute parameter to be queried. Accepted values are GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING, GL_VERTEX_ATTRIB_ARRAY_ENABLED, GL_VERTEX_ATTRIB_ARRAY_SIZE, GL_VERTEX_ATTRIB_ARRAY_STRIDE, GL_VERTEX_ATTRIB_ARRAY_TYPE, GL_VERTEX_ATTRIB_ARRAY_NORMALIZED, GL_VERTEX_ATTRIB_ARRAY_INTEGER, GL_VERTEX_ATTRIB_ARRAY_DIVISOR, or GL_CURRENT_VERTEX_ATTRIB.

params

Returns the requested data.

Description

glGetVertexAttrib returns in params the value of a generic vertex attribute parameter. The generic vertex attribute to be queried is specified by index, and the parameter to be queried is specified by pname.

The accepted parameter names are as follows:

GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING

params returns a single value, the name of the buffer object currently bound to the binding point corresponding to generic vertex attribute array index. If no buffer object is bound, 0 is returned. The initial value is 0.

GL_VERTEX_ATTRIB_ARRAY_ENABLED

params returns a single value that is non-zero (true) if the vertex attribute array for index is enabled and 0 (false) if it is disabled. The initial value is GL_FALSE.

GL_VERTEX_ATTRIB_ARRAY_SIZE

params returns a single value, the size of the vertex attribute array for index. The size is the number of values for each element of the vertex attribute array, and it will be 1, 2, 3, or 4. The initial value is 4.

GL_VERTEX_ATTRIB_ARRAY_STRIDE

params returns a single value, the array stride for (number of bytes between successive elements in) the vertex attribute array for index. A value of 0 indicates that the array elements are stored sequentially in memory. The initial value is 0.

GL_VERTEX_ATTRIB_ARRAY_TYPE

params returns a single value, a symbolic constant indicating the array type for the vertex attribute array for index. Possible values are GL_BYTE, GL_UNSIGNED_BYTE, GL_SHORT, GL_UNSIGNED_SHORT, GL_INT, GL_INT_2_10_10_10_REV, GL_UNSIGNED_INT, GL_FIXED, GL_HALF_FLOAT, and GL_FLOAT. The initial value is GL_FLOAT.

GL_VERTEX_ATTRIB_ARRAY_NORMALIZED

params returns a single value that is non-zero (true) if fixed-point data types for the vertex attribute array indicated by index are normalized when they are converted to floating point, and 0 (false) otherwise. The initial value is GL_FALSE.

GL_VERTEX_ATTRIB_ARRAY_INTEGER

params returns a single value that is non-zero (true) if fixed-point data types for the vertex attribute array indicated by index have integer data types, and 0 (false) otherwise. The initial value is 0 (GL_FALSE).

GL_VERTEX_ATTRIB_ARRAY_DIVISOR

params returns a single value that is the frequency divisor used for instanced rendering. See glVertexAttribDivisor. The initial value is 0.

GL_CURRENT_VERTEX_ATTRIB

params returns four values that represent the current value for the generic vertex attribute specified by index. The initial value for all generic vertex attributes is (0,0,0,1).

All of the parameters except GL_CURRENT_VERTEX_ATTRIB represent state stored in the currently bound vertex array object. If the zero object is bound, these values are client state.

Notes

If an error is generated, no change is made to the contents of params.

Errors

GL_INVALID_VALUE is generated if index is greater than or equal to GL_MAX_VERTEX_ATTRIBS.

GL_INVALID_ENUM is generated if pname is not an accepted value.

Associated Gets

glGet with argument GL_MAX_VERTEX_ATTRIBS

glGetVertexAttribPointerv with arguments index and GL_VERTEX_ATTRIB_ARRAY_POINTER

See Also

glBindAttribLocation, glBindBuffer, glDisableVertexAttribArray, glEnableVertexAttribArray, glVertexAttrib, glVertexAttribDivisor, glVertexAttribPointer

Copyright

Copyright © 2003-2005 3Dlabs Inc. Ltd. Copyright © 2010-2012 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. http://opencontent.org/openpub/.