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glDrawRangeElements(3G)
Contents
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glDrawRangeElements - render primitives from array data
void glDrawRangeElements(
GLenum mode,
GLuint start,
GLuint end,
GLsizei count,
GLenum type,
const GLvoid *indices );
Specifies what kind of primitives to render. Symbolic constants
GL_POINTS, GL_LINE_STRIP, GL_LINE_LOOP, GL_LINES,
GL_TRIANGLE_STRIP, GL_TRIANGLE_FAN, GL_TRIANGLES,
GL_QUAD_STRIP, GL_QUADS, and GL_POLYGON are accepted.
Specifies the minimum array index contained in indices.
Specifies the maximum array index contained in indices.
Specifies the number of elements to be rendered. Specifies
the type of the values in count. Must be one of
GL_UNSIGNED_BYTE, GL_UNSIGNED_SHORT, or GL_UNSIGNED_INT.
Specifies a pointer to the location where the indices are
stored.
glDrawRangeElements() is a restricted form of glDrawElements().
mode, start, end, and count match the corresponding
arguments to glDrawElements(), with the additional
constraint that all values in the arrays count must
lie between start and end, inclusive.
Implementations denote recommended maximum amounts of vertex
and index data, which may be queried by calling
glGet() with argument GL_MAX_ELEMENTS_VERTICES and
GL_MAX_ELEMENTS_INDICES. If "end" - "start" + 1 is
greater than the value of GL_MAX_ELEMENTS_VERTICES, or if
count is greater than the value of GL_MAX_ELEMENTS_INDICES,
then the call may operate at reduced performance.
There is no requirement that all vertices in
the range [start, end] be referenced. However, the implementation
may partially process unused vertices, reducing
performance from what could be achieved with an optimal
index set.
When glDrawRangeElements() is called, it uses start
sequential elements from an enabled array, starting at
count to construct a sequence of geometric primitives.
mode specifies what kind of primitives are constructed,
and how the array elements construct these primitives. If
more than one array is enabled, each is used. If GL_VERTEX_ARRAY
is not enabled, no geometric primitives are constructed.
Vertex attributes that are modified by glDrawRangeElements()
have an unspecified value after glDrawRangeElements()
returns. For example, if GL_COLOR_ARRAY is
enabled, the value of the current color is undefined after
glDrawRangeElements() executes. Attributes that aren't
modified maintain their previous values.
glDrawRangeElements() is available only if the GL version
is 1.2 or greater.
glDrawRangeElements() is included in display lists. If
glDrawRangeElements() is entered into a display list, the
necessary array data (determined by the array pointers and
enables) is also entered into the display list. Because
the array pointers and enables are client-side state,
their values affect display lists when the lists are created,
not when the lists are executed.
It is an error for indices to lie outside the range
[start, end], but implementations may not check for this
situation. Such indices cause implementation-dependent
behavior.
GL_INVALID_ENUM is generated if mode is not an accepted
value.
GL_INVALID_VALUE is generated if count is negative.
GL_INVALID_VALUE is generated if end < start.
GL_INVALID_OPERATION is generated if glDrawRangeElements()
is executed between the execution of glBegin() and the
corresponding glEnd().
glGet() with argument GL_MAX_ELEMENTS_VERTICES
glGet() with argument GL_MAX_ELEMENTS_INDICES
glArrayElement(3), glColorPointer(3), glDrawArrays(3),
glDrawElements(3), glEdgeFlagPointer(3), glGetPointerv(3),
glIndexPointer(3), glInterleavedArrays(3), glNormalPointer(3), glTexCoordPointer(3), glVertexPointer(3)
glDrawRangeElements(3G)
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