1GLDRAWELEMENTS(3G)                                          GLDRAWELEMENTS(3G)
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NAME

6       glDrawElements - render primitives from array data
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C SPECIFICATION

10       void glDrawElements( GLenum mode,
11                            GLsizei count,
12                            GLenum type,
13                            const GLvoid *indices )
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PARAMETERS

17       mode     Specifies  what  kind  of primitives to render.  Symbolic con‐
18                stants  GL_POINTS,  GL_LINE_STRIP,   GL_LINE_LOOP,   GL_LINES,
19                GL_TRIANGLE_STRIP,        GL_TRIANGLE_FAN,       GL_TRIANGLES,
20                GL_QUAD_STRIP, GL_QUADS, and GL_POLYGON are accepted.
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22       count    Specifies the number of elements to be rendered.
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24       type     Specifies the type of the values in indices. Must  be  one  of
25                GL_UNSIGNED_BYTE, GL_UNSIGNED_SHORT, or GL_UNSIGNED_INT.
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27       indices  Specifies  a  pointer  to  the  location where the indices are
28                stored.
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DESCRIPTION

31       glDrawElements specifies multiple geometric primitives  with  very  few
32       subroutine  calls.  Instead of calling a GL function to pass each indi‐
33       vidual vertex, normal, texture coordinate, edge flag, or color, you can
34       prespecify separate arrays of vertices, normals, and so on and use them
35       to  construct  a  sequence  of  primitives  with  a  single   call   to
36       glDrawElements.
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38       When  glDrawElements  is called, it uses count sequential elements from
39       an enabled array, starting at indices to construct a sequence  of  geo‐
40       metric  primitives.  mode  specifies  what  kind of primitives are con‐
41       structed, and how the array elements  construct  these  primitives.  If
42       more than one array is enabled, each is used. If GL_VERTEX_ARRAY is not
43       enabled, no geometric primitives are constructed.
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45       Vertex attributes that are modified by glDrawElements have an  unspeci‐
46       fied value after glDrawElements returns. For example, if GL_COLOR_ARRAY
47       is  enabled,  the  value  of  the  current  color  is  undefined  after
48       glDrawElements executes. Attributes that aren't modified maintain their
49       previous values.
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NOTES

52       glDrawElements is available only if the GL version is 1.1 or greater.
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54       glDrawElements is included  in  display  lists.  If  glDrawElements  is
55       entered  into  a  display list, the necessary array data (determined by
56       the array pointers and enables) is also entered into the display  list.
57       Because  the  array  pointers  and enables are client-side state, their
58       values affect display lists when the lists are created,  not  when  the
59       lists are executed.
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ERRORS

62       GL_INVALID_ENUM is generated if mode is not an accepted value.
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64       GL_INVALID_VALUE is generated if count is negative.
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66       GL_INVALID_OPERATION is generated if glDrawElements is executed between
67       the execution of glBegin and the corresponding glEnd.
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SEE ALSO

70       glArrayElement(3G),        glColorPointer(3G),        glDrawArrays(3G),
71       glDrawRangeElements(3G),    glEdgeFlagPointer(3G),   glGetPointerv(3G),
72       glIndexPointer(3G),    glInterleavedArrays(3G),    glNormalPointer(3G),
73       glTexCoordPointer(3G), glVertexPointer(3G)
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