mdwrigh2
Joined 17 years ago
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Comment · 1 month ago
> * Google drop "real" Android source-code updates to OEMs _and_ the public every half.
All of the major OEM shave access to the internal source with a _very_ small delay. OEMs don't ship these intermediate releases because they choose not to, not because Google witholds the source for them.
Comment · 1 year ago
Yeah, that's exactly what happened with the Pixel C. A lot of politics around who would own tablets and laptops at the time that meant the winds changed direction ~yearly, hence the horribly confusing product line ups that happened.
Comment · 1 year ago
Wrong Ian -- Ian Hickson wrote about that in a blogpost, this post is about Ian Lance Taylor
Comment · 2 years ago
You can disable them, which is functionally uninstalling. Actually being able to uninstall them isn't technically possible because their base images live on a read-only partition so they survive factory reset (which erases all RW partitions). The OS could _pretend_ they're uninstalled, but that seems strictly worse than the existing presentation which more accurately reflects reality.
Comment · 3 years ago
> When we refer to "log", this is almost always means a camera gamma - an OOTF.
Wouldn't this be the OETF? OOTF would include the EOTF, which is typically applied on the display side (as you noted).
Comment · 4 years ago
> The ritual to compile, pack and flash super.img into the device is absurd.
I typically only do a full flash for the first build after a sync. Afterwards I just build the pieces I'm changing and use `adb sync` to push them to the device, skipping both the step that packs the image files and the flash. The `sync` target will build just the pieces needed for an `adb sync` if you don't know exactly what you need to build; I typically use it so I don't have to even think about which pieces I'm changing when rebuilding.
So typical flow goes something like:
``` // Rebase is only needed if I have existing local changes > repo sync -j12 && repo rebase
// I don't actually use flashall, we have a tool internally that also handles bootloader upgrades, etc. > m -j && fastboot flashall
// Hack hack hack... then: > m -j sync && syncrestart ```
Where `syncrestart` is an alias for:
``` syncrestart () { adb remount && adb shell stop && sleep 3 && adb sync && adb shell start } ```
Incremental compiles while working on native code are ~10 seconds with this method. Working on framework Java code can be a couple minutes still because of the need to run metalava.
Comment · 4 years ago
I'm not the parent you're asking, but figure you might be interested anyways since I could've likely made the same comment:
I work on displays within an OS team. Having some basic understanding of colour theory is critical for a significant number of modern display projects, particularly for the high end. For example, enabling colour accurate rendering (games, photos, etc), shipping wide-gamut displays (how do you render existing content on a WCG display?), etc. More specifically to the planckian locus, it generally comes up when deciding which white point to calibrate a given display to at the factory (e.g. iPhone is 6470K, S20 is 7020K in Vivid)[1][2] and if you're doing any sort of chromatic white point adaptation, like Apple's True Tone[1][2].
My background before joining the team was a degree in math, but I really enjoyed doing low level projects in my spare time, so ended up on an OS team. We also have colour scientists who study this full time and have a _significantly_ better understanding of it all than I do :)
[1]: https://www.displaymate.com/iPhone_13Pro_ShootOut_1M.htm#Whi... [2]: https://www.displaymate.com/Galaxy_S20_ShootOut_1U.htm#White... [3]: https://support.apple.com/en-gb/HT208909 [4]: http://yuhaozhu.com/blog/chromatic-adaptation.html
Comment · 5 years ago
> It seems somewhat silly on a non-realtime OS to grab one frame, request a 15ms wait, and then grab another frame, when your deadline is 16.6ms
A couple reasons this isn't as silly as it seems
1) ~All buffers in Android are pipelined, usually with a queue depth of 2 or 3 depending on overall application performance. This means that missing a deadline is recoverable as long as it doesn't happen multiple times in a row. I'd also note that since Netflix probably only cares about synchronization and not latency during video play back they could have a buffer depth of nearly anything they wanted, but I don't think that's a knob Android exposes to applications.
2) The deadline is probably not the end of the current frame but rather than end of the next frame (i.e. ~18ms away) or further. The application can specify this with the presentation time EGL extension[1] that's required to be present on all Android devices.
[1]: https://www.khronos.org/registry/EGL/extensions/ANDROID/EGL_...
Comment · 6 years ago
Skia has been around for 15 years (open source for 12) and is used in a number of high priority projects for Google (e.g. Android, Chrome). It's incredibly unlikely it will be killed any time soon.
Comment · 6 years ago
> At a meta-level, I'm surprised that something with so factual (and testable) an answer can still not be settled.
It is absolutely settled, and has been tested over and over again. Power is roughly proportional to the amount of light emitted[1], so having dark grey is absolutely a power savings over pure white.
Google slides: https://www.theverge.com/2018/11/8/18076502/google-dark-mode... Display energy modeling: https://onlinelibrary.wiley.com/doi/am-pdf/10.1002/stvr.1635
[1]: This isn't totally true mostly because the display is broken into RGB elements emitting light of differing efficiencies and human perception of the brightness of those elements is not identical.
Comment · 6 years ago
It's "Don't be evil" and it's still in the code of conduct:
And remember… don’t be evil, and if you see something that you think isn’t right – speak up!
Comment · 6 years ago
Some of these exist:
> learn how to build Android from sources
https://source.android.com/setup/start has instructions.
> put some binary drivers from official image
https://source.android.com/setup/build/gsi is a set of builds you can flash on any sufficiently modern Android device alongside their binary drivers.
> May be even some guides how to reverse engineer proprietary drivers and rewrite them as open source.
You're on your own for this, but given the kernel and HAL APIs are both open source you could theoretically figure out how to build a viable implementation, but no matter how you go about it, building something like a GPU driver is a substantial task. You could probably build things like the lights HAL without too much difficulty though.