GLVERTEXPOINTER

Section: Misc. Reference Manual Pages (3G)
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NAME

glVertexPointer - define an array of vertex data

C SPECIFICATION

void glVertexPointer( GLint size,


                        GLenum type,
                        GLsizei stride,
                        const GLvoid *ptr )

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PARAMETERS

size: Specifies the number of coordinates per vertex; must be 2, 3, or 4. The initial value is 4.
type: Specifies the data type of each coordinate in the array. Symbolic constants GL_SHORT, GL_INT, GL_FLOAT, and GL_DOUBLE are accepted. The initial value is GL_FLOAT.
stride: Specifies the byte offset between consecutive vertices. If stride is 0, the vertices are understood to be tightly packed in the array. The initial value is 0.
ptr: Specifies a pointer to the first coordinate of the first vertex in the array. The initial value is 0.

DESCRIPTION

glVertexPointer specifies the location and data of an array of vertex coordinates to use when rendering. size specifies the number of coordinates per vertex and type the data type of the coordinates. stride specifies the byte stride from one vertex to the next allowing vertices and attributes to be packed into a single array or stored in separate arrays. (Single-array storage may be more efficient on some implementations; see glInterleavedArrays.) When a vertex array is specified, size, type, stride, and ptr are saved as client-side state. To enable and disable the vertex array, call glEnableClientState and
glDisableClientState with the argument GL_VERTEX_ARRAY. If enabled, the vertex array is used when glDrawArrays, glDrawElements, or glArrayElement is called. Use glDrawArrays to construct a sequence of primitives (all of the same type) from prespecified vertex and vertex attribute arrays. Use glArrayElement to specify primitives by indexing vertices and vertex attributes and glDrawElements to construct a sequence of primitives by indexing vertices and vertex attributes.

NOTES

glVertexPointer is available only if the GL version is 1.1 or greater. The vertex array is initially disabled and isn't accessed when glArrayElement, glDrawElements or glDrawArrays is called. Execution of glVertexPointer is not allowed between the execution of glBegin and the corresponding execution of glEnd, but an error may or may not be generated. If no error is generated, the operation is undefined. glVertexPointer is typically implemented on the client side. Vertex array parameters are client-side state and are therefore not saved or restored by glPushAttrib and glPopAttrib. Use glPushClientAttrib and glPopClientAttrib instead.

ERRORS

GL_INVALID_VALUE is generated if size is not 2, 3, or 4. GL_INVALID_ENUM is generated if type is is not an accepted value. GL_INVALID_VALUE is generated if stride is negative.

ASSOCIATED GETS

glIsEnabled with argument GL_VERTEX_ARRAY
glGet with argument GL_VERTEX_ARRAY_SIZE
glGet with argument GL_VERTEX_ARRAY_TYPE
glGet with argument GL_VERTEX_ARRAY_STRIDE
glGetPointerv with argument GL_VERTEX_ARRAY_POINTER