1. Computers
  2. Display Drivers
  3. Graphics Cards
  4. Memory
  5. Motherboards
  6. Processors
  7. Software
  8. Storage
  9. Operating Systems


Facebook RSS Twitter Twitter Google Plus


Phoronix Test Suite

OpenBenchmarking.org

A Look At Android's Graphics Rendering Pipeline

Google

Published on 06 December 2011 08:24 PM EST
Written by Michael Larabel in Google
2 Comments

For those interested in Android and graphics, here's a look at their graphics rendering pipeline as written by a long-time Android developer.

Dianne Hackborn, an Android Framework Engineer going back to 2005, has written on Google+ various facts about the Android graphics pipeline. Dianne wrote this public posting to correct the information that's out there about Android graphics. Below are some of her more interesting comments.
- "Full" hardware accelerated drawing within a window was added in Android 3.0. The implementation in Android 4.0 is not any more full than in 3.0. Starting with 3.0, if you set the flag in your app saying that hardware accelerated drawing is allowed, then all drawing to the application’s windows will be done with the GPU. The main change in this regard in Android 4.0 is that now apps that are explicitly targeting 4.0 or higher will have acceleration enabled by default rather than having to put android:handwareAccelerated="true" in their manifest.

- Hardware accelerated drawing is not all full of win. For example on the PVR drivers of devices like the Nexus S and Galaxy Nexus, simply starting to use OpenGL in a process eats about 8MB of RAM. Given that our process overhead is about 2MB, this is pretty huge. That RAM takes away from other things, such as the number of background processes that can be kept running, potentially slowing down things like app switching.

- Because of the overhead of OpenGL, one may very well not want to use it for drawing. For example some of the work we are doing to make Android 4.0 run well on the Nexus S has involved turning off hardware accelerated drawing in parts of the UI so we don’t lose 8MB of RAM in the system process, another 8MB in the phone process, another 8MB in the system UI process, etc...

- ...To get 60fps animation, Android 3.0 and later use a number of tricks. A big one is that it tries to put all windows into overlays instead of having to copy them to the framebuffer with the GPU. In the case here even with that we are still over-budget, but we have another trick: because the wallpaper on Android is in a separate window, we can make this window larger than the screen to hold the entire bitmap. Now, as you scroll, the movement of the background doesn’t require any drawing, just moving its window... and because this window is in an overlay, it doesn’t even need to be composited to the screen with the GPU.

Read more in her Google+ posting, which is likely of interest to many Phoronix readers due to the graphics hardware focus.

As of this August, there's mainline support in Mesa/Gallium3D for Android too, but that's more relevant to Android for x86.

About The Author
Michael Larabel is the principal author of Phoronix.com and founded the web-site in 2004 with a focus on enriching the Linux hardware experience and being the largest web-site devoted to Linux hardware reviews, particularly for products relevant to Linux gamers and enthusiasts but also commonly reviewing servers/workstations and embedded Linux devices. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics hardware drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated testing software. He can be followed via and or contacted via .
Latest Linux Hardware Reviews
  1. AMD Launches New FX CPUs, Cuts Prices On Existing Processors
  2. Preview: AMD's FX-9590 Eight-Core At Up To 5.0GHz On Linux
  3. Intel Launches The Core i7 5960X, Mighty Powerful Haswell-E CPUs
  4. AMD Radeon R9 290: Gallium3D vs. Catalyst Drivers
Latest Linux Articles
  1. Ondemand vs. Performance CPU Governing For AMD FX CPUs On Linux 3.17
  2. How Intel Graphics On Linux Compare To Open-Source AMD/NVIDIA Drivers
  3. The Fastest NVIDIA GPUs For Open-Source Nouveau With Steam Linux Gaming
  4. Testing For The Latest Linux Kernel Power Regression
Latest Linux News
  1. Borderlands 2 Is Coming To Linux
  2. The Witcher 2 Ups The Performance More & Works Around Catalyst Bug
  3. Running Gallium3D's LLVMpipe On The Eight-Core 5GHz CPU
  4. Trying Intel OpenCL On Linux For Video Encoding
  5. GSoC 2014 Yielded Some Improvements For Mesa/X.Org This Year
  6. webOS Lives On As LuneOS With New Release
  7. Marek Lands Radeon Gallium3D HyperZ Improvements
  8. Mozilla Firefox 32 Surfaces With HTML5, Developer Changes
  9. Nouveau X.Org Driver Released With DRI3+Present, Maxwell, GLAMOR
  10. Microsoft & AMD Release C++ AMP Compiler With Linux Support
Latest Forum Discussions
  1. Lennart Poettering Talks Up His New Linux Vision That Involves Btrfs
  2. nv and xorg.conf under Debian PPC
  3. AMD graphics doesn't work with AMD Catalyst drivers
  4. Best Radeon for a Power Mac G5?
  5. The dangers of Linux kernel development
  6. Updated and Optimized Ubuntu Free Graphics Drivers
  7. AMD Releases UVD Video Decode Support For R600 GPUs
  8. SSD seems slow