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WEBGL_multi_draw: multiDrawElementsWEBGL() method

files/en-us/web/api/webgl_multi_draw/multidrawelementswebgl/index.md

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{{APIRef("WebGL")}}

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

Syntax

js-nolint
multiDrawElementsWEBGL(mode,
    countsList, countsOffset,
    type,
    firstsList, firstsOffset,
    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.

  • countsList

  • countsOffset

    • : A GLUint defining the starting point into the countsList array.

  • type

    • : A GLenum specifying the type of the values in the element array buffer. Possible values are:

  • offsetsList

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

  • offsetsOffset

    • : A GLuint defining the starting point into the offsetsList 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 countsList or offsetsList are negative, a gl.INVALID_VALUE error is thrown.

Examples

js
const counts = new Int32Array(/* … */);
const offsets = new Int32Array(/* … */);
ext.multiDrawElementsWEBGL(
  gl.TRIANGLES,
  counts,
  0,
  gl.UNSIGNED_SHORT,
  offsets,
  0,
  counts.length,
);

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also