glColorPointer(3G) OpenGL Reference glColorPointer(3G)
glColorPointer - define an array of colors
void glColorPointer( GLint size,
GLenum type,
GLsizei stride,
const GLvoid *pointer )
size Specifies the number of components per color. Must be 3 or 4.
The initial value is 4.
type Specifies the data type of each color component in the array.
Symbolic constants GL_BYTE, GL_UNSIGNED_BYTE, GL_SHORT,
GL_UNSIGNED_SHORT, GL_INT, GL_UNSIGNED_INT, GL_FLOAT, and
GL_DOUBLE are accepted. The initial value is GL_FLOAT.
stride Specifies the byte offset between consecutive colors. If stride
is 0 (the initial value), the colors are understood to be
tightly packed in the array. The initial value is 0.
pointer Specifies a pointer to the first component of the first color
element in the array.
glColorPointer specifies the location and data format of an array of
color components to use when rendering. size specifies the number of
components per color, and must be 3 or 4. type specifies the data type
of each color component, and stride specifies the byte stride from one
color 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 color array is specified, size, type, stride, and pointer are
saved as client-side state.
To enable and disable the color array, call glEnableClientState and
glDisableClientState with the argument GL_COLOR_ARRAY. If enabled, the
color array is used when glDrawArrays, glDrawElements,
glDrawRangeElements, or glArrayElement is called.
glColorPointer is available only if the GL version is 1.1 or greater.
The color array is initially disabled and isn't accessed when
glArrayElement, glDrawArrays, glDrawRangeElements, or glDrawElements is
called.
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glColorPointer(3G) OpenGL Reference glColorPointer(3G)
Execution of glColorPointer 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.
glColorPointer is typically implemented on the client side.
Color array parameters are client-side state and are therefore not saved
or restored by glPushAttrib and glPopAttrib. Use glPushClientAttrib and
glPopClientAttrib instead.
GL_INVALID_VALUE is generated if size is not 3 or 4.
GL_INVALID_ENUM is generated if type is not an accepted value.
GL_INVALID_VALUE is generated if stride is negative.
glIsEnabled with argument GL_COLOR_ARRAY
glGet with argument GL_COLOR_ARRAY_SIZE
glGet with argument GL_COLOR_ARRAY_TYPE
glGet with argument GL_COLOR_ARRAY_STRIDE
glGetPointerv with argument GL_COLOR_ARRAY_POINTER
MACHINE DEPENDENCIES
On RealityEngine, RealityEngine2, and VTX systems, do not enable or
disable GL_VERTEX_ARRAY, GL_VERTEX_ARRAY_EXT, GL_NORMAL_ARRAY,
GL_NORMAL_ARRAY_EXT, GL_COLOR_ARRAY, GL_COLOR_ARRAY_EXT,
GL_INDEX_ARRAY,GL_INDEX_ARRAY_EXT, GL_TEXTURE_COORD_ARRAY,
GL_TEXTURE_COORD_ARRAY_EXT, GL_EDGE_FLAG_ARRAY or GL_EDGE_FLAG_ARRAY_EXT
between a call to glNewList and the corresponding call to glEndList.
Instead, enable or disable before the call to glNewList.
On InfiniteReality systems it is particularly important to minimize the
amount of data transferred from the application to the graphics pipe,
since the host-to-pipe bandwidth limit can cause a performance
bottleneck. One way to reduce the amount of data transferred per vertex
is to use properly-aligned byte and short data types whenever possible.
Accordingly, the EXT_vertex_array extension on InfiniteReality systems
has been optimized for vertex information packed into the following data
structures. (Note: v represents vertex coordinates, c represents color
components, n represents normal coordinates, and t represents texture
coordinates. Normals must have unit length.)
struct {GLfloat v[3];}
struct {GLubyte c[4]; GLfloat v[3];}
struct {GLshort n[3]; GLfloat v[3];}
struct {GLubyte c[4]; GLshort n[3]; GLfloat v[3];}
struct {GLshort t[2]; GLfloat v[3];}
struct {GLshort t[2]; GLubyte c[4]; GLfloat v[3];}
struct {GLshort t[2]; GLshort n[3]; GLfloat v[3];}
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glColorPointer(3G) OpenGL Reference glColorPointer(3G)
struct {GLshort t[2]; GLubyte c[4]; GLshort n[3]; GLfloat v[3];}
struct {GLfloat t[2]; GLfloat v[3];}
struct {GLfloat t[2]; GLubyte c[4]; GLfloat v[3];}
struct {GLfloat t[2]; GLshort n[3]; GLfloat v[3];}
struct {GLfloat t[2]; GLubyte c[4]; GLshort n[3]; GLfloat v[3];}
Application-specific fields may be added to these structures, provided
that all the fields described above retain their relative order and word
alignment.
An additional constraint applies when glTexGen is being used. The
implementation normally generates all four texture coordinates in
parallel, and must take special action to generate just a subset of the
four coordinates. Therefore performance is best when none of the texture
coordinates are being generated, or when all of them are being generated.
For example, when using 2D texturing (generating s and t coordinates) it
will be faster to enable texture coordinate generation for the r and q
coordinates as well as s and t. Choose a texture generation mode of
GL_OBJECT_LINEAR and use the plane equations (0,0,0,0) and (0,0,0,1) for
r and q, respectively.
Using these structures on InfiniteReality systems can improve performance
considerably, compared to structures in which all values are singleprecision
floating point.
glArrayElement, glDrawArrays, glDrawElements, glEdgeFlagPointer,
glEnable, glGetPointerv, glIndexPointer, glInterleavedArrays,
glNormalPointer, glPopClientAttrib, glPushClientAttrib,
glTexCoordPointer, glVertexPointer
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