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XRWebGLBinding: createCylinderLayer() method

files/en-us/web/api/xrwebglbinding/createcylinderlayer/index.md

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{{APIRef("WebXR Device API")}}{{SeeCompatTable}}

The createCylinderLayer() method of the {{domxref("XRWebGLBinding")}} interface returns an {{domxref("XRCylinderLayer")}} object, which is a layer that takes up a curved rectangular space in the virtual environment.

Syntax

js-nolint
createCylinderLayer(init)

Parameters

  • init
    • : An object to configure the {{domxref("XRCylinderLayer")}}. It must have the space, viewPixelHeight, and viewPixelWidth properties. init has the following properties:
      • aspectRatio {{optional_inline}}
        • : A number indicating the ratio of the visible cylinder section. It is the ratio of the width of the visible section of the cylinder divided by its height. The width is calculated by multiplying the radius with the centralAngle. The default value is 2.0.
      • centralAngle {{optional_inline}}
        • : A number indicating the angle in radians of the visible section of the cylinder. Default value: 0.78539 (π / 4).
      • colorFormat {{optional_inline}}
        • : A {{domxref("WebGL_API/Types", "GLenum")}} defining the data type of the color texture data. Possible values:
          • gl.RGB
          • gl.RGBA Additionally, for contexts with the {{domxref("EXT_sRGB")}} extension enabled:
          • ext.SRGB_EXT
          • ext.SRGB_ALPHA_EXT Additionally, for {{domxref("WebGL2RenderingContext")}} contexts:
          • gl.RGBA8
          • gl.RGB8
          • gl.SRGB8
          • gl.RGB8_ALPHA8 Additionally, for contexts with the {{domxref("WEBGL_compressed_texture_etc")}} extension enabled:
          • ext.COMPRESSED_RGB8_ETC2
          • ext.COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2
          • ext.COMPRESSED_RGBA8_ETC2_EAC
          • ext.COMPRESSED_SRGB8_ETC2
          • ext.COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2
          • ext.COMPRESSED_SRGB8_ALPHA8_ETC2_EAC Additionally, for contexts with the {{domxref("WEBGL_compressed_texture_astc")}} extension enabled:
          • All of the formats the extension supports. The default value is gl.RGBA.
      • depthFormat {{optional_inline}}
        • : A {{domxref("WebGL_API/Types", "GLenum")}} defining the data type of the depth texture data or 0 indicating that the layer should not provide a depth texture (in that case {{domxref("XRProjectionLayer.ignoreDepthValues")}} will be true). Possible values within {{domxref("WebGLRenderingContext")}} contexts with the {{domxref("WEBGL_depth_texture")}} extension enabled, or within {{domxref("WebGL2RenderingContext")}} contexts (no extension required):
          • gl.DEPTH_COMPONENT
          • gl.DEPTH_STENCIL Additionally, for {{domxref("WebGL2RenderingContext")}} contexts:
          • gl.DEPTH_COMPONENT24
          • gl.DEPTH24_STENCIL24 The default value is gl.DEPTH_COMPONENT.
      • isStatic {{optional_inline}}
        • : A boolean that, if true, indicates you can only draw to this layer when {{domxref("XRCompositionLayer.needsRedraw", "needsRedraw")}} is true. The default value is false.
      • layout {{optional_inline}}
        • : A string indicating the layout of the layer. Possible values:
          • default
            • : The layer accommodates all views of the session.
          • mono
            • : A single {{domxref("XRSubImage")}} is allocated and presented to both eyes.
          • stereo
            • : The user agent decides how it allocates the {{domxref("XRSubImage")}} (one or two) and the layout (top/bottom or left/right).
          • stereo-left-right
            • : A single {{domxref("XRSubImage")}} is allocated. Left eye gets the left area of the texture, right eye the right.
          • stereo-top-bottom
            • : A single {{domxref("XRSubImage")}} is allocated. Left eye gets the top area of the texture, right eye the bottom. The default value is mono.
      • mipLevels {{optional_inline}}
        • : A number specifying desired number of mip levels. The default value is 1.
      • radius {{optional_inline}}
        • : A number indicating the radius of the cylinder. Default value: 2.0.
      • space Required
        • : An {{domxref("XRSpace")}} object defining the layer's spatial relationship with the user's physical environment.
      • textureType {{optional_inline}}
        • : A string defining the type of texture the layer will have. Possible values:
          • texture: The textures of {{domxref("XRWebGLSubImage")}} will be of type gl.TEXTURE_2D.
          • texture-array: the textures of {{domxref("XRWebGLSubImage")}} will be of type gl.TEXTURE_2D_ARRAY (WebGL 2 contexts only). The default value is texture.
      • transform {{optional_inline}}
        • : An {{domxref("XRRigidTransform")}} object defining the offset and orientation relative to space.
      • viewPixelHeight Required
        • : A number specifying the pixel height of the layer view.
      • viewPixelWidth Required
        • : A number specifying the pixel width of the layer view.

Return value

An {{domxref("XRCylinderLayer")}} object.

Examples

Creating an XRCylinderLayer

Configure the cylinder layer using the properties listed above in a call to createCylinderLayer(). To present layers to the XR device, add them to the layers render state using {{domxref("XRSession.updateRenderState()")}}.

js
function onXRSessionStarted(xrSession) {
  const glCanvas = document.createElement("canvas");
  const gl = glCanvas.getContext("webgl2", { xrCompatible: true });
  const xrGlBinding = new XRWebGLBinding(xrSession, gl);
  const cylinderLayer = xrGlBinding.createCylinderLayer({
    space: xrReferenceSpace,
    viewPixelWidth: 1200,
    viewPixelHeight: 600,
    centralAngle: (60 * Math.PI) / 180,
    aspectRatio: 2,
    radius: 2,
    transform: new XRRigidTransform(/* … */),
  });

  xrSession.updateRenderState({
    layers: [cylinderLayer],
  });
}

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also