WebGLRenderingContext: getFramebufferAttachmentParameter() method

Note: This feature is available in Web Workers.

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

Syntax

js
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:

When using a WebGL 2 context, the following values are available additionally:

When using the WEBGL_draw_buffers extension:

pname

A GLenum specifying information to query. Possible values:

When using the EXT_sRGB extension:

When using a WebGL 2 context, the following values are available additionally:

When using the OVR_multiview2 extension:

Return value

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

pname parameterReturn value
gl.FRAMEBUFFER_ATTACHMENT_OBJECT_TYPEA GLenum indicating the type of the texture. Either gl.RENDERBUFFER, gl.TEXTURE, or if no image is attached, gl.NONE.
gl.FRAMEBUFFER_ATTACHMENT_OBJECT_NAMEThe texture (WebGLTexture) or renderbuffer (WebGLRenderbuffer) of the attached image.
gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVELA GLint indicating the mipmap level. Default value: 0.
gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACEA 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_SIZEA GLint indicating the number of bits in the alpha component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_BLUE_SIZEA GLint indicating the number of bits in the blue component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_COLOR_ENCODINGA GLenum indicating the encoding of components of the specified attachment. Either gl.LINEAR or gl.SRGB.
gl.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPEA 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_SIZEA GLint indicating the number of bits in the depth component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_GREEN_SIZEA GLint indicating the number of bits in the green component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_RED_SIZEA GLint indicating the number of bits in the red component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_STENCIL_SIZEA GLint indicating the number of bits in the stencil component of the attachment.
gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYERA GLint indicating the number of the texture layer which contains the attached image.
ext.FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING_EXTA GLenum indicating the framebuffer color encoding. Either gl.LINEAR or ext.SRGB_EXT.
ext.FRAMEBUFFER_ATTACHMENT_TEXTURE_NUM_VIEWS_OVRA GLsizei indicating the number of views of the framebuffer object attachment.
ext.FRAMEBUFFER_ATTACHMENT_TEXTURE_BASE_VIEW_INDEX_OVRA GLint indicating the base view index of the framebuffer object attachment.

Exceptions

Examples

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

Specifications

See also