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EXT_color_buffer_half_float extension

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨September 2020⁩.

The EXT_color_buffer_half_float extension is part of the WebGL API and adds the ability to render to 16-bit floating-point color buffers.

WebGL extensions are available using the WebGLRenderingContext.getExtension() method. For more information, see also Using Extensions in the WebGL tutorial.

Note: This extension is available to both, WebGL1 and WebGL2 contexts. On WebGL 2, it's an alternative to using the EXT_color_buffer_float extension on platforms that support 16-bit floating point render targets but not 32-bit floating point render targets.

The OES_texture_half_float extension implicitly enables this extension.

Constants

ext.RGBA16F_EXT: RGBA 16-bit floating-point color-renderable format.
ext.RGB16F_EXT: RGB 16-bit floating-point format. In WebGL 1.0, this may be color-renderable (implementation-dependent). In WebGL 2.0, this format is not color-renderable.
ext.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE_EXT: Passed to WebGLRenderingContext.getFramebufferAttachmentParameter() to get the framebuffer type.
ext.UNSIGNED_NORMALIZED_EXT: The framebuffer contains unsigned fixed-point components.

Extended methods

This extension extends WebGLRenderingContext.renderbufferStorage():

In WebGL 1.0 contexts, the internalFormat parameter now accepts ext.RGBA16F_EXT and ext.RGB16F_EXT. However, ext.RGB16F_EXT support is optional and applications must check framebuffer completeness to determine if it's supported.
In WebGL 2.0 contexts, the internalFormat parameter now accepts ext.RGBA16F_EXT. The RGB16F format is not color-renderable in WebGL 2.0.

It extends WebGLRenderingContext.getFramebufferAttachmentParameter():

In WebGL 1.0 contexts, the pname parameter now accepts ext.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE_EXT. An INVALID_OPERATION error is generated if attachment is DEPTH_STENCIL_ATTACHMENT and pname is FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE_EXT. When pname is ext.FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE_EXT, getFramebufferAttachmentParameter() returns either gl.FLOAT or gl.UNSIGNED_NORMALIZED_EXT for floating-point or unsigned fixed-point components respectively.

Examples

const ext = gl.getExtension("EXT_color_buffer_half_float");

gl.renderbufferStorage(gl.RENDERBUFFER, ext.RGBA16F_EXT, 256, 256);

Specifications

Specification
WebGL EXT_color_buffer_half_float Extension Specification>

Browser compatibility