C SPECIFICATION

void glGetVertexAttribdv(GLuint index, GLenum pname, GLdouble *params);

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);

void glGetVertexAttribLdv(GLuint index, GLenum pname, GLdouble *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_UNSIGNED_INT, GL_FLOAT, and GL_DOUBLE. 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. Generic vertex attribute 0 is unique in that it has no current state, so an error will be generated if index is 0. The initial value for all other generic vertex attributes is (0,0,0,1).

glGetVertexAttribdv and glGetVertexAttribfv return the current attribute values as four single-precision floating-point values; glGetVertexAttribiv reads them as floating-point values and converts them to four integer values; glGetVertexAttribIiv and glGetVertexAttribIuiv read and return them as signed or unsigned integer values, respectively; glGetVertexAttribLdv reads and returns them as four double-precision floating-point values.

All of the parameters except GL_CURRENT_VERTEX_ATTRIB represent state stored in the currently bound vertex array object.

NOTES

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

ASSOCIATED GETS

glGet() with argument GL_MAX_VERTEX_ATTRIBS

glGetVertexAttribPointerv() with arguments index and GL_VERTEX_ATTRIB_ARRAY_POINTER

COPYRIGHT

Copyright © 2003-2005 3Dlabs Inc. Ltd. Copyright © 2010 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. m[blue]http://opencontent.org/openpub/m[].