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.

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

None (undefined).

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]
]);

• WEBGL_draw_buffers
• WebGLRenderingContext.getExtension()
• WebGLRenderingContext.framebufferRenderbuffer()
• WebGLRenderingContext.framebufferTexture2D()
• WebGLRenderingContext.getFramebufferAttachmentParameter()
• WebGLRenderingContext.getParameter()
• WebGL deferred shading - Mozilla Hacks blog