2013
Khronos Group
glVertexAttribFormat
3G
glVertexAttribFormat
specify the organization of vertex arrays
C Specification
void glVertexAttribFormat
GLuint attribindex
GLint size
GLenum type
GLboolean normalized
GLuint relativeoffset
void glVertexAttribIFormat
GLuint attribindex
GLint size
GLenum type
GLuint relativeoffset
void glVertexAttribLFormat
GLuint attribindex
GLint size
GLenum type
GLuint relativeoffset
Parameters
attribindex
The generic vertex attribute array being described.
size
The number of values per vertex that are stored in the array.
type
The type of the data stored in the array.
normalized
The distance between elements within the buffer.
relativeoffset
The distance between elements within the buffer.
Description
glVertexAttribFormat, glVertexAttribIFormat and
glVertexAttribLFormat specify the organization of data in vertex arrays.
attribindex specifies the index of the generic vertex attribute
array whose data layout is being described, and must be less
than the value of GL_MAX_VERTEX_ATTRIBS.
size determines the number of components per vertex are allocated
to the specifed attribute and must be 1, 2, 3 or 4. type indicates
the type of the data. If type is one of GL_BYTE,
GL_SHORT, GL_INT, GL_FIXED,
GL_FLOAT, GL_HALF_FLOAT, and
GL_DOUBLE indicate types GLbyte
, GLshort
,
GLint
, GLfixed
, GLfloat
, GLhalf
, and
GLdouble
, respectively; the values GL_UNSIGNED_BYTE,
GL_UNSIGNED_SHORT, and GL_UNSIGNED_INT indicate types
GLubyte
, GLushort
, and GLuint
,
respectively; the values GL_INT_2_10_10_10_REV and
GL_UNSIGNED_INT_2_10_10_10_REV indicating respectively four signed or
unsigned elements packed into a single GLuint
; and the value
GL_UNSIGNED_INT_10F_11F_11F_REV indicating three floating point values
packed into a single GLuint
.
glVertexAttribLFormat is used to specify layout for
data associated with a generic attribute variable declared as 64-bit double precision
components. For glVertexAttribLFormat, type
must be GL_DOUBLE. In contrast to glVertexAttribFormat,
which will cause data declared as GL_DOUBLE to be converted to 32-bit
representation, glVertexAttribLFormat causes such data to be left
in its natural, 64-bit representation.
For glVertexAttribFormat, if normalized is
GL_TRUE, then integer data is normalized to the range [-1, 1] or
[0, 1] if it is signed or unsigned, respectively. If noramlized is
GL_FALSE then integer data is directly converted to floating point.
relativeoffset is the offset, measured in basic machine units
of the first element relative to the start of the vertex buffer binding this attribute
fetches from.
glVertexAttribFormat should be used to describe vertex attribute
layout for floating-point vertex attributes, glVertexAttribIFormat
should be used to describe vertex attribute layout for integer vertex attribute
and glVertexAttribLFormat should be used to describe the layout
for 64-bit vertex attributes. Data for an array specified by
glVertexAttribIFormat will always be left as integer values;
such data are referred to as pure integers.
Notes
GL_UNSIGNED_INT_10F_11F_11F_REV is accepted for type
only if the GL version is 4.4 or higher.
Errors
GL_INVAILD_VALUE is generated if attribindex is greater than
or equal to the value of GL_MAX_VERTEX_ATTRIBS.
GL_INVALID_VALUE is generated if size is not
one of the accepted values.
GL_INVALID_VALUE is generated if relativeoffset is greater
than the value of GL_MAX_VERTEX_ATTRIB_RELATIVE_OFFSET.
GL_INVALID_ENUM is generated if type is not
one of the accepted tokens.
GL_INVALID_OPERATION is generated if no vertex array object is bound.
Associated Gets
glGet with arguments GL_MAX_VERTEX_ATTRIB_BINDINGS,
or GL_MAX_VERTEX_ATTRIB_RELATIVE_OFFSET.
glGetVertexAttrib with argument GL_VERTEX_ATTRIB_RELATIVE_OFFSET.
See Also
glBindVertexBuffer,
glVertexAttribBinding,
glVertexAttribPointer,
glVertexBindingDivisor,
glVertexAttribPointer.
Copyright
Copyright 2013 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/.