Note: This feature is available in Web Workers.
The WebGL2RenderingContext.drawElementsInstanced() method of the WebGL 2 API renders primitives from array data like the gl.drawElements() method. In addition, it can execute multiple instances of a set of elements.
Note: When using WebGL 1, the ANGLE_instanced_arrays extension can provide this method, too.
drawElementsInstanced(mode, count, type, offset, instanceCount)modeA GLenum specifying the type primitive to render. Possible values are:
gl.POINTS: Draws a single dot.gl.LINE_STRIP: Draws a straight line to the next vertex.gl.LINE_LOOP: Draws a straight line to the next vertex, and connects the last vertex back to the first.gl.LINES: Draws a line between a pair of vertices.gl.TRIANGLE_STRIPgl.TRIANGLE_FANgl.TRIANGLES: Draws a triangle for a group of three vertices.countA GLsizei specifying the number of elements to be rendered.
typeA GLenum specifying the type of the values in the element array buffer. Possible values are:
gl.UNSIGNED_BYTEgl.UNSIGNED_SHORTgl.UNSIGNED_INT When using the OES_element_index_uint extension.offsetA GLintptr specifying an offset in the element array buffer. Must be a valid multiple of the size of the given type.
instanceCountA GLsizei specifying the number of instances of the set of elements to execute.
None (undefined).
mode is not one of the accepted values, a gl.INVALID_ENUM error is thrown.offset is a valid multiple of the size of the given type, a gl.INVALID_OPERATION error is thrown.count or instanceCount are negative, a gl.INVALID_VALUE error is thrown.gl.drawElementsInstanced(gl.POINTS, 2, gl.UNSIGNED_SHORT, 0, 4);