docs/gpu/swiftshader.md - chromium/src.git - Git at Google

 # Using Chromium with SwiftShader

 SwiftShader is an open-source high-performance implementation of the Vulkan and OpenGL ES graphics APIs which runs purely on the CPU. Thus no graphics processor (GPU) is required for advanced (3D) graphics.

 Chromium uses SwiftShader in two different ways:

 1) **As the OpenGL ES driver**

 When Chromium uses SwiftShader as the OpenGL ES driver, Chromium behaves as if it was running a on regular GPU, while actually running on SwiftShader. This allows Chromium to exercise hardware only code paths on GPU-less bots.

 2) **As the WebGL fallback**

 When Chromium uses SwiftShader as the WebGL fallback, Chromium runs in all software mode and only uses SwiftShader to render WebGL content.

 SwiftShader also provides 2 different libraries:

 1) **The legacy SwiftShader Open GL ES libraries**

 Legacy SwiftShader includes a GLES library and an EGL library, in order to provide a complete solution to run OpenGL ES content.

 *Do not use these libraries if possible, they are being phased out in favor of SwANGLE (ANGLE + SwiftShader Vulkan).*

 2) **The SwiftShader Vulkan library**

 SwiftShader Vulkan can be used both to render Vulkan content directly, or OpenGL ES content when use in conjunction with the ANGLE library.

 ## Relevant Chromium command line switches

 When running the **chrome** executable from the command line, SwiftShader can be enabled using the following Switches:
 1) As the OpenGL ES driver, SwANGLE (ANGLE + SwiftShader Vulkan)
 >**\-\-use-gl=angle \-\-use-angle=swiftshader**
 2) As the WebGL fallback, SwANGLE (ANGLE + SwiftShader Vulkan)
 >**\-\-use-gl=angle \-\-use-angle=swiftshader-webgl**
 3) As the OpenGL ES driver, legacy SwiftShader Open GL ES libraries
 > **\-\-use-gl=swiftshader**
 4) As the WebGL fallback, legacy SwiftShader Open GL ES libraries
 >**\-\-use-gl=swiftshader-webgl**
 5) As the Vulkan driver (requires the [enable_swiftshader_vulkan](https://source.chromium.org/chromium/chromium/src/+/master:gpu/vulkan/features.gni;l=16) feature)
 >**--use-vulkan=swiftshader**
	# Using Chromium with SwiftShader

	SwiftShader is an open-source high-performance implementation of the Vulkan and OpenGL ES graphics APIs which runs purely on the CPU. Thus no graphics processor (GPU) is required for advanced (3D) graphics.

	Chromium uses SwiftShader in two different ways:

	1) As the OpenGL ES driver

	When Chromium uses SwiftShader as the OpenGL ES driver, Chromium behaves as if it was running a on regular GPU, while actually running on SwiftShader. This allows Chromium to exercise hardware only code paths on GPU-less bots.

	2) As the WebGL fallback

	When Chromium uses SwiftShader as the WebGL fallback, Chromium runs in all software mode and only uses SwiftShader to render WebGL content.

	SwiftShader also provides 2 different libraries:

	1) The legacy SwiftShader Open GL ES libraries

	Legacy SwiftShader includes a GLES library and an EGL library, in order to provide a complete solution to run OpenGL ES content.

	Do not use these libraries if possible, they are being phased out in favor of SwANGLE (ANGLE + SwiftShader Vulkan).

	2) The SwiftShader Vulkan library

	SwiftShader Vulkan can be used both to render Vulkan content directly, or OpenGL ES content when use in conjunction with the ANGLE library.

	## Relevant Chromium command line switches

	When running the chrome executable from the command line, SwiftShader can be enabled using the following Switches:
	1) As the OpenGL ES driver, SwANGLE (ANGLE + SwiftShader Vulkan)
	>\-\-use-gl=angle \-\-use-angle=swiftshader
	2) As the WebGL fallback, SwANGLE (ANGLE + SwiftShader Vulkan)
	>\-\-use-gl=angle \-\-use-angle=swiftshader-webgl
	3) As the OpenGL ES driver, legacy SwiftShader Open GL ES libraries
	> \-\-use-gl=swiftshader
	4) As the WebGL fallback, legacy SwiftShader Open GL ES libraries
	>\-\-use-gl=swiftshader-webgl
	5) As the Vulkan driver (requires the [enable_swiftshader_vulkan](https://source.chromium.org/chromium/chromium/src/+/master:gpu/vulkan/features.gni;l=16) feature)
	>--use-vulkan=swiftshader