Extracted from Pike v7.3 release 16 at 2002-03-05.
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GL

Method GL.glDrawArrays()


Method glDrawArrays

void GL.glDrawArrays(int mode, int first, int count)

Description

GL.glDrawArrays specifies multiple geometric primitives with very few subroutine calls. Instead of calling a GL procedure to pass each individual vertex, normal, texture coordinate, edge flag, or color, you can prespecify separate arrays of vertexes, normals, and colors and use them to construct a sequence of primitives with a single call to GL.glDrawArrays.

When GL.glDrawArrays is called, it uses count sequential elements from each enabled array to construct a sequence of geometric primitives, beginning with element first. mode specifies what kind of primitives are constructed, and how the array elements construct those primitives. If GL_VERTEX_ARRAY is not enabled, no geometric primitives are generated.

Vertex attributes that are modified by GL.glDrawArrays have an unspecified value after GL.glDrawArrays returns. For example, if GL_COLOR_ARRAY is enabled, the value of the current color is undefined after GL.glDrawArrays executes. Attributes that aren't modified remain well defined.

Parameter mode

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.

Parameter first

Specifies the starting index in the enabled arrays.

Parameter count

Specifies the number of indices to be rendered.

Throws

GL_INVALID_ENUM is generated if mode is not an accepted value.

GL_INVALID_VALUE is generated if count is negative.

GL_INVALID_OPERATION is generated if GL.glDrawArrays is executed between the execution of GL.glBegin and the corresponding GL.glEnd.