WebGLRenderingContext: clear() method

{{APIRef("WebGL")}}{{AvailableInWorkers}}

The WebGLRenderingContext.clear() method of the WebGL API clears buffers to preset values.

The preset values can be set by {{domxref("WebGLRenderingContext.clearColor", "clearColor()")}}, {{domxref("WebGLRenderingContext.clearDepth", "clearDepth()")}} or {{domxref("WebGLRenderingContext.clearStencil", "clearStencil()")}}.

The scissor box, dithering, and buffer writemasks can affect the clear() method. For example, if buffer writing is disabled via {{domxref("WebGLRenderingContext.colorMask", "colorMask()")}}, {{domxref("WebGLRenderingContext.depthMask", "depthMask()")}}, or {{domxref("WebGLRenderingContext.stencilMask", "stencilMask()")}}, clear() has no effect on the corresponding buffer.

Syntax

clear(mask)

Parameters

• mask
  • : A {{domxref("WebGL_API/Types", "GLbitfield")}} bitwise OR mask that indicates the buffers to be cleared. Possible values are:
    • gl.COLOR_BUFFER_BIT
    • gl.DEPTH_BUFFER_BIT
    • gl.STENCIL_BUFFER_BIT

Return value

None ({{jsxref("undefined")}}).

Exceptions

If mask is not one of the listed possible values, a gl.INVALID_ENUM error is thrown.

Examples

The clear() method accepts multiple values.

gl.clear(gl.DEPTH_BUFFER_BIT);
gl.clear(gl.DEPTH_BUFFER_BIT | gl.COLOR_BUFFER_BIT);

To get the current clear values, query the COLOR_CLEAR_VALUE, DEPTH_CLEAR_VALUE, and STENCIL_CLEAR_VALUE constants.

gl.getParameter(gl.COLOR_CLEAR_VALUE);
gl.getParameter(gl.DEPTH_CLEAR_VALUE);
gl.getParameter(gl.STENCIL_CLEAR_VALUE);

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}

See also

• {{domxref("WebGLRenderingContext.clearColor()")}}
• {{domxref("WebGLRenderingContext.clearDepth()")}}
• {{domxref("WebGLRenderingContext.clearStencil()")}}