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<HTML><BODY><PRE> <STRONG>NAME</STRONG> <STRONG>glDrawElements</STRONG> - render primitives from array data <STRONG>C</STRONG> <STRONG>SPECIFICATION</STRONG> void <STRONG>glDrawElements</STRONG>( GLenum <EM>mode</EM>, GLsizei <EM>count</EM>, GLenum <EM>type</EM>, const GLvoid *<EM>indices</EM> ) <STRONG>PARAMETERS</STRONG> <EM>mode</EM> Specifies what kind of primitives to render. Symbolic constants <STRONG>GL_POINTS</STRONG>, <STRONG>GL_LINE_STRIP</STRONG>, <STRONG>GL_LINE_LOOP</STRONG>, <STRONG>GL_LINES</STRONG>, <STRONG>GL_TRIANGLE_STRIP</STRONG>, <STRONG>GL_TRIANGLE_FAN</STRONG>, <STRONG>GL_TRIANGLES</STRONG>, <STRONG>GL_QUAD_STRIP</STRONG>, <STRONG>GL_QUADS</STRONG>, and <STRONG>GL_POLYGON</STRONG> are accepted. <EM>count</EM> Specifies the number of elements to be rendered. <EM>type</EM> Specifies the type of the values in <EM>indices</EM>. Must be one of <STRONG>GL_UNSIGNED_BYTE</STRONG>, <STRONG>GL_UNSIGNED_SHORT</STRONG>, or <STRONG>GL_UNSIGNED_INT</STRONG>. <EM>indices</EM> Specifies a pointer to the location where the indices are stored. <STRONG>DESCRIPTION</STRONG> <STRONG>glDrawElements</STRONG> specifies multiple geometric primitives with very few subroutine calls. Instead of calling a GL function to pass each individual vertex, normal, texture coordinate, edge flag, or color, you can prespecify separate arrays of vertexes, normals, and so on and use them to construct a sequence of primitives with a single call to <STRONG>glDrawElements</STRONG>. When <STRONG>glDrawElements</STRONG> is called, it uses <EM>count</EM> sequential elements from an enabled array, starting at <EM>indices</EM> to construct a sequence of geometric primitives. <EM>mode</EM> 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 <STRONG>GL_VERTEX_ARRAY</STRONG> is not enabled, no geometric primitives are constructed. Vertex attributes that are modified by <STRONG>glDrawElements</STRONG> have an unspecified value after <STRONG>glDrawElements</STRONG> returns. For example, if <STRONG>GL_COLOR_ARRAY</STRONG> is enabled, the value of the current color is undefined after <STRONG>glDrawElements</STRONG> executes. Attributes that aren't modified remain well defined. <STRONG>NOTES</STRONG> <STRONG>glDrawElements</STRONG> is available only if the GL version is 1.1 or greater. <STRONG>glDrawElements</STRONG> is included in display lists. If <STRONG>glDrawElements</STRONG> 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. <STRONG>ERRORS</STRONG> <STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>mode</EM> is not an accepted value. <STRONG>GL_INVALID_VALUE</STRONG> is generated if <EM>count</EM> is negative. <STRONG>GL_INVALID_OPERATION</STRONG> is generated if <STRONG>glDrawElements</STRONG> is executed between the execution of <STRONG>glBegin</STRONG> and the corresponding <STRONG>glEnd</STRONG>. <STRONG>SEE</STRONG> <STRONG>ALSO</STRONG> <STRONG>glArrayElement</STRONG>, <STRONG>glColorPointer</STRONG>, <STRONG>glDrawArrays</STRONG>, <STRONG>glEdgeFlagPointer</STRONG>, <STRONG>glGetPointerv</STRONG>, <STRONG>glIndexPointer</STRONG>, <STRONG>glInterleavedArrays</STRONG>, <STRONG>glNormalPointer</STRONG>, <STRONG>glTexCoordPointer</STRONG>, <STRONG>glVertexPointer</STRONG></PRE></BODY></HTML>⌨️ 快捷键说明
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