glColorPointerEXT(3G) OpenGL Reference glColorPointerEXT(3G)
glColorPointerEXT - define a array of colors
void glColorPointerEXT( GLint size,
GLenum type,
GLsizei stride,
GLsizei count,
const GLvoid *pointer )
size Specifies the number of components per color. It must be 3 or 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, or
GL_DOUBLE_EXT, are accepted.
stride Specifies the byte offset between consecutive colors. If stride
is zero the colors are understood to be tightly packed in the
array.
count Specifies the number of colors, counting from the first, that
are static.
pointer Specifies a pointer to the first component of the first color
element in the array.
glColorPointerEXT specifies the location and data format of an array of
color components to use when rendering using the vertex array extension.
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 gives 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. (Singlearray
storage may be more efficient on some implementations.) count
indicates the number of array elements (counting from the first) that are
static. Static elements may be modified by the application, but once they
are modified, the application must explicitly respecify the array before
using it for any rendering. When a color array is specified, size, type,
stride, count and pointer are saved as client-side state, and static
array elements may be cached by the implementation.
The color array is enabled and disabled using glEnable and glDisable with
the argument GL_COLOR_ARRAY_EXT. If enabled, the color array is used when
glDrawArraysEXT or glArrayElementEXT is called.
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glColorPointerEXT(3G) OpenGL Reference glColorPointerEXT(3G)
Use glDrawArraysEXT to define a sequence of primitives (all of the same
type) from pre-specified vertex and vertex attribute arrays. Use
glArrayElementEXT to specify primitives by indexing vertices and vertex
attributes.
Non-static array elements are not accessed until glArrayElementEXT or
glDrawArraysEXT is executed.
By default the color array is disabled and it won't be accessed when
glArrayElementEXT or glDrawArraysEXT is called.
Although it is not an error to call glColorPointerEXT between the
execution of glBegin and the corresponding execution of glEnd, the
results are undefined.
glColorPointerEXT will typically be implemented on the client side with
no protocol.
Since the color array parameters are client side state, they are not
saved or restored by glPushAttrib and glPopAttrib.
glColorPointerEXT commands are not entered into display lists.
glColorPointerEXT is part of the EXT_vertex_array extension, not part of
the core GL command set. If GL_EXT_vertex_array is included in the string
returned by glGetString, when called with argument GL_EXTENSIONS,
extension EXT_vertex_array is supported.
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 or count is negative.
glIsEnabled with argument GL_COLOR_ARRAY_EXT
glGet with argument GL_COLOR_ARRAY_SIZE_EXT
glGet with argument GL_COLOR_ARRAY_TYPE_EXT
glGet with argument GL_COLOR_ARRAY_STRIDE_EXT
glGet with argument GL_COLOR_ARRAY_COUNT_EXT
glGetPointervEXT with argument GL_COLOR_ARRAY_POINTER_EXT
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glColorPointerEXT(3G) OpenGL Reference glColorPointerEXT(3G)
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];}
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.
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glColorPointerEXT(3G) OpenGL Reference glColorPointerEXT(3G)
glArrayElementEXT, glDrawArraysEXT, glEdgeFlagPointerEXT, glEnable,
glGetPointervEXT, glIndexPointerEXT, glNormalPointerEXT,
glTexCoordPointerEXT, glVertexPointerEXT
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