Method GL.glDrawElements()

Method glDrawElements

void glDrawElements(int mode, array(int) indices)

Description

glDrawElements 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 glDrawElements.

When glDrawElements is called, it uses sequential elements from an enabled array indices 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 glDrawElements have an unspecified value after glDrawElements returns. For example, if GL_COLOR_ARRAY is enabled, the value of the current color is undefined after glDrawElements 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 indices

Specifies an array of indices.

Throws

GL_INVALID_ENUM is generated if mode is not an accepted value.

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