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WEBGL_draw_buffers: drawBuffersWEBGL() method

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

The WEBGL_draw_buffers.drawBuffersWEBGL() method is part of the WebGL API and allows you to define the draw buffers to which all fragment colors are written.

This method is part of the WEBGL_draw_buffers extension.

Note: When using WebGL2, this method is available as gl.drawBuffers() by default and the constants are named gl.COLOR_ATTACHMENT1 etc. without the "WEBGL" suffix.

Syntax

drawBuffersWEBGL(buffers)

Parameters

buffers

An Array of GLenum constants defining drawing buffers. Possible values:

gl.NONE: The fragment shader is not written to any color buffer.
gl.BACK: The fragment shader is written to the back color buffer.
ext.COLOR_ATTACHMENT0_WEBGL The fragment shader is written the n-th color attachment of the framebuffer.
ext.COLOR_ATTACHMENT1_WEBGL
ext.COLOR_ATTACHMENT2_WEBGL
ext.COLOR_ATTACHMENT3_WEBGL
ext.COLOR_ATTACHMENT4_WEBGL
ext.COLOR_ATTACHMENT5_WEBGL
ext.COLOR_ATTACHMENT6_WEBGL
ext.COLOR_ATTACHMENT7_WEBGL
ext.COLOR_ATTACHMENT8_WEBGL
ext.COLOR_ATTACHMENT9_WEBGL
ext.COLOR_ATTACHMENT10_WEBGL
ext.COLOR_ATTACHMENT11_WEBGL
ext.COLOR_ATTACHMENT12_WEBGL
ext.COLOR_ATTACHMENT13_WEBGL
ext.COLOR_ATTACHMENT14_WEBGL
ext.COLOR_ATTACHMENT15_WEBGL

Return value

None (undefined).

Examples

See WEBGL_draw_buffers for more context with this example code.

ext.drawBuffersWEBGL([
  ext.COLOR_ATTACHMENT0_WEBGL, // gl_FragData[0]
  ext.COLOR_ATTACHMENT1_WEBGL, // gl_FragData[1]
  ext.COLOR_ATTACHMENT2_WEBGL, // gl_FragData[2]
  ext.COLOR_ATTACHMENT3_WEBGL, // gl_FragData[3]
]);

Specifications

Specification
WebGL WEBGL_draw_buffers Khronos Ratified Extension Specification>

Browser compatibility

	Desktop					Mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS
`drawBuffersWEBGL`	36	17	28	23	9	No	No	No	15	No	No	15