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WEBGL_multi_draw: multiDrawArraysInstancedWEBGL() method

The WEBGL_multi_draw.multiDrawArraysInstancedWEBGL() method of the WebGL API renders multiple primitives from array data. It is identical to multiple calls to the gl.drawArraysInstanced() method.

Syntax

multiDrawArraysInstancedWEBGL(mode,
    firstsList, firstsOffset,
    countsList, countsOffset,
    instanceCountsList, instanceCountsOffset,
    drawCount);

Parameters

mode

A 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_STRIP
gl.TRIANGLE_FAN
gl.TRIANGLES: Draws a triangle for a group of three vertices.

firstsList

An Int32Array or Array (of GLint) specifying a list of starting indices for the arrays of vector points.

firstsOffset

A GLuint defining the starting point into the firstsLists array.

countsList

An Int32Array or Array (of GLsizei) specifying a list of numbers of indices to be rendered.

countsOffset

A GLuint defining the starting point into the countsList array.

instanceCountsList

An Int32Array or Array (of GLsizei) specifying a list of numbers of instances of the range of elements to execute.

instanceCountsOffset

A GLuint defining the starting point into the instanceCountsList array.

drawCount

A GLsizei specifying the number of instances of the range of elements to execute.

Return value

None.

Exceptions

If mode is not one of the accepted values, a gl.INVALID_ENUM error is thrown.
If drawCount or items in firstsList, countsList, or instanceCountsList are negative, a gl.INVALID_VALUE error is thrown.
if gl.CURRENT_PROGRAM is null, a gl.INVALID_OPERATION error is thrown.

Examples

const firsts = new Int32Array(/* … */);
const counts = new Int32Array(/* … */);
const instanceCounts = new Int32Array(/* … */);
ext.multiDrawArraysInstancedWEBGL(
  gl.TRIANGLES,
  firsts,
  0,
  counts,
  0,
  instanceCounts,
  0,
  firsts.length,
);

Specifications

Specification
WebGL WEBGL_multi_draw Extension Specification

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	WebView Android	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet
`multiDrawArraysInstancedWEBGL`	86	86	No	No	72	15	86	86	No	No	15	14.0