WEBGL_multi_draw.multiDrawArraysWEBGL()

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

Syntax

void ext.multiDrawArraysWEBGL(mode,
    firstsList, firstsOffset,
    countsList, countsOffset,
    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.

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 and countsList are negative, a gl.INVALID_VALUE error is thrown.
• if gl.CURRENT_PROGRAM is null, a gl.INVALID_OPERATION error is thrown.

Examples

// let firsts = new Int32Array(...);
// let counts = new Int32Array(...);
ext.multiDrawArraysWEBGL(gl.TRIANGLES, firsts, 0, counts, 0, firsts.length);

Specifications

Browser compatibility

See also

• WebGLRenderingContext.drawArrays()
• WebGL2RenderingContext.drawArraysInstanced()