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---
title: "WebGLRenderingContext: getFramebufferAttachmentParameter() method"
short-title: getFramebufferAttachmentParameter()
slug: Web/API/WebGLRenderingContext/getFramebufferAttachmentParameter
page-type: web-api-instance-method
browser-compat: api.WebGLRenderingContext.getFramebufferAttachmentParameter
---
{{APIRef("WebGL")}}
The
**`WebGLRenderingContext.getFramebufferAttachmentParameter()`**
method of the [WebGL API](/en-US/docs/Web/API/WebGL_API) returns information
about a framebuffer's attachment.
## Syntax
```js-nolint
getFramebufferAttachmentParameter(target, attachment, pname)
```
### Parameters
- `target`
- : A {{domxref("WebGL_API/Types", "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 {{domxref("WebGL2RenderingContext", "WebGL 2 context", "", 1)}},
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 {{domxref("WebGL_API/Types", "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 {{domxref("WebGL2RenderingContext", "WebGL 2 context", "", 1)}},
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 {{domxref("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 {{domxref("WebGL_API/Types", "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 ({{domxref("WebGLRenderbuffer")}} or
{{domxref("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 {{domxref("EXT_sRGB")}} extension:
- `ext.FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING_EXT`: The framebuffer
color encoding.
When using a {{domxref("WebGL2RenderingContext", "WebGL 2 context", "", 1)}},
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 {{domxref("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
{{domxref("WebGL_API/Types", "GLint")}}, a {{domxref("WebGL_API/Types", "GLenum")}}, a {{domxref("WebGLRenderbuffer")}}, or a
{{domxref("WebGLTexture")}}.
<table class="standard-table">
<thead>
<tr>
<th scope="col"><code>pname</code> parameter</th>
<th scope="col">Return value</th>
</tr>
</thead>
<tbody>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLenum")}} indicating the
type of the texture. Either <code>gl.RENDERBUFFER</code>,
<code>gl.TEXTURE</code>, or if no image is attached,
<code>gl.NONE</code>.
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_OBJECT_NAME</code></td>
<td>
The texture ({{domxref("WebGLTexture")}}) or renderbuffer
({{domxref("WebGLRenderbuffer")}}) of the attached image.
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLint")}} indicating the
mipmap level. Default value: 0.
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLenum")}} indicating the
name of cube-map face of the texture. Possible values:
<ul>
<li>
<code>gl.TEXTURE_CUBE_MAP_POSITIVE_X</code>: Image for the positive
X face of the cube.
</li>
<li>
<code>gl.TEXTURE_CUBE_MAP_NEGATIVE_X</code>: Image for the negative
X face of the cube.
</li>
<li>
<code>gl.TEXTURE_CUBE_MAP_POSITIVE_Y</code>: Image for the positive
Y face of the cube.
</li>
<li>
<code>gl.TEXTURE_CUBE_MAP_NEGATIVE_Y</code>: Image for the negative
Y face of the cube.
</li>
<li>
<code>gl.TEXTURE_CUBE_MAP_POSITIVE_Z</code>: Image for the positive
Z face of the cube.
</li>
<li>
<code>gl.TEXTURE_CUBE_MAP_NEGATIVE_Z</code>: Image for the negative
Z face of the cube.
</li>
</ul>
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLint")}} indicating the
number of bits in the alpha component of the attachment.
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_BLUE_SIZE</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLint")}} indicating the
number of bits in the blue component of the attachment.
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLenum")}} indicating the
encoding of components of the specified attachment. Either
<code>gl.LINEAR</code> or <code>gl.SRGB</code>.
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLenum")}} indicating the
format of the components of the specified attachment. Either
<code>gl.FLOAT</code>, <code>gl.INT</code>,
<code>gl.UNSIGNED_INT</code>, <code>gl.SIGNED_NORMALIZED</code>, or
<code>gl.UNSIGNED_NORMALIZED</code>.
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLint")}} indicating the
number of bits in the depth component of the attachment.
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_GREEN_SIZE</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLint")}} indicating the
number of bits in the green component of the attachment.
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_RED_SIZE</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLint")}} indicating the
number of bits in the red component of the attachment.
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLint")}} indicating the
number of bits in the stencil component of the attachment.
</td>
</tr>
<tr>
<td><code>gl.FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYER</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLint")}} indicating the
number of the texture layer which contains the attached image.
</td>
</tr>
<tr>
<td><code>ext.FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING_EXT</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLenum")}} indicating the
framebuffer color encoding. Either <code>gl.LINEAR</code> or
<code>ext.SRGB_EXT</code>.
</td>
</tr>
<tr>
<td><code>ext.FRAMEBUFFER_ATTACHMENT_TEXTURE_NUM_VIEWS_OVR</code></td>
<td>
A {{domxref("WebGL_API/Types", "GLsizei")}} indicating
the number of views of the framebuffer object attachment.
</td>
</tr>
<tr>
<td>
<code>ext.FRAMEBUFFER_ATTACHMENT_TEXTURE_BASE_VIEW_INDEX_OVR</code>
</td>
<td>
A {{domxref("WebGL_API/Types", "GLint")}} indicating the
base view index of the framebuffer object attachment.
</td>
</tr>
</tbody>
</table>
### 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
```js
gl.getFramebufferAttachmentParameter(
gl.FRAMEBUFFER,
gl.COLOR_ATTACHMENT0,
gl.FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE,
);
```
## Specifications
{{Specifications}}
## Browser compatibility
{{Compat}}
## See also
- {{domxref("WebGLRenderingContext.createFramebuffer()")}}
- {{domxref("WebGLRenderingContext.deleteFramebuffer()")}}
- {{domxref("WebGLRenderingContext.isFramebuffer()")}}
- Other buffers: {{domxref("WebGLBuffer")}}, {{domxref("WebGLRenderbuffer")}}
- {{domxref("EXT_sRGB")}}
- {{domxref("WEBGL_draw_buffers")}}