Web/API/WebGLRenderingContext/getFramebufferAttachmentParameter

From Get docs


The WebGLRenderingContext.getFramebufferAttachmentParameter() method of the WebGL API returns information about a framebuffer's attachment.

Syntax

any gl.getFramebufferAttachmentParameter(target, attachment, pname);

Parameters

target
A GLenum specifying the binding point (target). Possible values:
gl.FRAMEBUFFER
  • Collection buffer data storage of color, alpha, depth and stencil buffers used to render an image.
  • When using a WebGL 2 context, the following values are available additionally:
gl.DRAW_FRAMEBUFFER
    • Equivalent to gl.FRAMEBUFFER. Used as a destination for drawing, rendering, clearing, and writing operations.
    • gl.READ_FRAMEBUFFER: Used as a source for reading operations.
attachment
A GLenum specifying the attachment point for the texture. Possible values:
gl.COLOR_ATTACHMENT0
  • Texture attachment for the framebuffer's color buffer.
  • gl.DEPTH_ATTACHMENT: Texture attachment for the framebuffer's depth buffer.
  • gl.STENCIL_ATTACHMENT: Texture attachment for the framebuffer's stencil buffer.
  • gl.DEPTH_STENCIL_ATTACHMENT: Texture attachment for both, the depth and stencil buffer.
  • When using a WebGL 2 context, the following values are available additionally:
    • gl.COLOR_ATTACHMENT1 gl.COLOR_ATTACHMENT2 gl.COLOR_ATTACHMENT3 gl.COLOR_ATTACHMENT4 gl.COLOR_ATTACHMENT5 gl.COLOR_ATTACHMENT6 gl.COLOR_ATTACHMENT7 gl.COLOR_ATTACHMENT8 gl.COLOR_ATTACHMENT9 gl.COLOR_ATTACHMENT10 gl.COLOR_ATTACHMENT11 gl.COLOR_ATTACHMENT12 gl.COLOR_ATTACHMENT13 gl.COLOR_ATTACHMENT14 gl.COLOR_ATTACHMENT15
When using the WEBGL_draw_buffers extension
    • ext.COLOR_ATTACHMENT0_WEBGL (same as gl.COLOR_ATTACHMENT0) 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
pname
A GLenum specifying information to query. Possible values:
gl.FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE
  • The type which contains the attached image.
  • gl.FRAMEBUFFER_ATTACHMENT_OBJECT_NAME: The texture or renderbuffer of the attached image (WebGLRenderbuffer or WebGLTexture).
  • gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL: Mipmap level. Default value: 0.
  • gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE: The name of cube-map face of the texture.
  • When using the EXT_sRGB extension:
ext.FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING_EXT
    • The framebuffer color encoding.
When using a WebGL 2 context, the following values are available additionally
    • gl.FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE
    • gl.FRAMEBUFFER_ATTACHMENT_BLUE_SIZE
    • gl.FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING
    • gl.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE
    • gl.FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE
    • gl.FRAMEBUFFER_ATTACHMENT_GREEN_SIZE
    • gl.FRAMEBUFFER_ATTACHMENT_RED_SIZE
    • gl.FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE
    • gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYER
When using the OVR_multiview2 extension
ext.FRAMEBUFFER_ATTACHMENT_TEXTURE_NUM_VIEWS_OVR
    • the number of views of the framebuffer object attachment.
    • ext.FRAMEBUFFER_ATTACHMENT_TEXTURE_BASE_VIEW_INDEX_OVR:  the base view index of the framebuffer object attachment.

Return value

Depends on the requested information (as specified with pname). Either a GLint, a GLenum, a WebGLRenderbuffer, or a WebGLTexture.

pname parameter Return value
gl.FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE A GLenum indicating the type of the texture. Either gl.RENDERBUFFER, gl.TEXTURE, or if no image is attached, gl.NONE.
gl.FRAMEBUFFER_ATTACHMENT_OBJECT_NAME The texture (WebGLTexture) or renderbuffer (WebGLRenderbuffer) of the attached image.
gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL A GLint indicating the mipmap level. Default value: 0.
gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE

A GLenum indicating the name of cube-map face of the texture. Possible values:

  • gl.TEXTURE_CUBE_MAP_POSITIVE_X: Image for the positive X face of the cube.
  • gl.TEXTURE_CUBE_MAP_NEGATIVE_X: Image for the negative X face of the cube.
  • gl.TEXTURE_CUBE_MAP_POSITIVE_Y: Image for the positive Y face of the cube.
  • gl.TEXTURE_CUBE_MAP_NEGATIVE_Y: Image for the negative Y face of the cube.
  • gl.TEXTURE_CUBE_MAP_POSITIVE_Z: Image for the positive Z face of the cube.
  • gl.TEXTURE_CUBE_MAP_NEGATIVE_Z: Image for the negative Z face of the cube.
gl.FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE A GLint indicating the number of bits in the alpha component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_BLUE_SIZE A GLint indicating the number of bits in the blue component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING A GLenum indicating the encoding of components of the specified attachment. Either gl.LINEAR or gl.SRGB.
gl.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE A GLenum indicating the format of the components of the specified attachment. Either gl.FLOAT, gl.INT, gl.UNSIGNED_INT, gl.SIGNED_NORMALIZED, or gl.UNSIGNED_NORMALIZED.
gl.FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE A GLint indicating the number of bits in the depth component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_GREEN_SIZE A GLint indicating the number of bits in the green component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_RED_SIZE A GLint indicating the number of bits in the red component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE A GLint indicating the number of bits in the stencil component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYER A GLint indicating the number of the texture layer which contains the attached image.
ext.FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING_EXT A GLenum indicating the framebuffer color encoding. Either gl.LINEAR or ext.SRGB_EXT.
ext.FRAMEBUFFER_ATTACHMENT_TEXTURE_NUM_VIEWS_OVR A GLsizei indicating the number of views of the framebuffer object attachment.
ext.FRAMEBUFFER_ATTACHMENT_TEXTURE_BASE_VIEW_INDEX_OVR A GLint indicating the base view index of the framebuffer object attachment.

Exceptions

  • A gl.INVALID_ENUM error is thrown if target is not gl.FRAMEBUFFER, gl.DRAW_FRAMEBUFFER, gl.READ_FRAMEBUFFER or if attachment is not one of the accepted attachment points.

Examples

gl.getFramebufferAttachmentParameter(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, 
                                     gl.FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE);

Specifications

Specification Status Comment
WebGL 1.0The definition of 'getFramebufferAttachmentParameter' in that specification. Recommendation Initial definition for WebGL.
OpenGL ES 2.0The definition of 'glGetFramebufferAttachmentParameteriv' in that specification. Standard Man page of the (similar) OpenGL API.
WebGL 2.0The definition of 'getFramebufferAttachmentParameter' in that specification. Editor's Draft Updated definition for WebGL 2.
OpenGL ES 3.0The definition of 'glGetFramebufferAttachmentParameteriv' in that specification. Standard Man page of the (similar) OpenGL ES 3 API.

Browser compatibility

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
getFramebufferAttachmentParameter Chrome

Full support 9

Edge

Full support 12

Firefox

Full support 4

IE

Full support 11

Opera

Full support 12

Safari

Full support 5.1

WebView Android

Full support Yes

Chrome Android

Full support 25

Firefox Android

Full support Yes

Opera Android

Full support 12

Safari iOS

Full support 8

Samsung Internet Android

Full support 1.5

WebGL2 Chrome

Full support 56

Edge

Full support 79

Firefox

Full support 51

IE

No support No

Opera

Full support 43

Safari

No support No

WebView Android

Full support 58

Chrome Android

Full support 58

Firefox Android

Full support 51

Opera Android

Full support 43

Safari iOS

No support No

Samsung Internet Android

Full support 7.0

Legend

Full support  
Full support
No support  
No support


See also