Learn to accel(erate)

G(PU) force
Hardware acceleration
By Royi Benyossef (+royiby)

G(PU)-force by Royi Benyossef (+royiby)
Android developer since 2009.
GDG Herzliya co-founder.
Android speaker and lecturer.
Android Mentor for Google Launchpad.
Android GDE 2013, 2014, 2015.
Android group leader at Vidmind.
Royi Benyossef

Motivation

With a little help from my libs by Royi Benyossef (+royiby)
Motivation
Great UX

Motivation
Great UX Sleek transitions

Motivation
Great UX Sleek transitions
Smooth animations

HOW?

Hardware
accelerationHOW?

Prolog
What is hardware acceleration?

Prolog
Definition

Prolog
Definition Graphics rendered by the GPU

Prolog
- Definition
In Android
Graphics rendered by the GPU

Prolog
- Definition
In Android
Canvas drawn by the GPU

Prolog
- Definition
In Android
(= HW drawing model)

Prolog
- Definition
In Android
NOT Canvas drawn by the CPU

Prolog
- Definition
In Android
NOT Canvas drawn by the CPU
(!= SW drawing model)

Android drawing models
(Let me dig deeper… please)

SW model

SW model Invalidate hierarchy

SW model Invalidate hierarchy
Draw hierarchy

- SW model
HW model
Invalidate hierarchy
Draw hierarchy

- SW model
HW model
Draw hierarchy

- SW model
HW model
Draw hierarchy
Record & update display lists

- SW model
HW model
Draw hierarchy
Record & update display lists
Draw hierarchy

Not sure ifstupid...
Or didn’tmake hispoint yet...

OnInvalidate()
(How it differs between the SW and HW models)
(P.S. also point #1)

OnInvalidate()
SW model

OnInvalidate()
SW model Calling item is redrawn

OnInvalidate()
All affiliated items are
redrawn

OnInvalidate()
All affiliated items are
redrawn
* Executed immediately

OnInvalidate()
- SW model
HW model

OnInvalidate()
- SW model
HW model
Calling item is saved to the
display list

OnInvalidate()
- SW model
HW model
display list
Display list is updated

OnInvalidate()
- SW model
HW model
display list
Diff is drawn

OnInvalidate()
- SW model
HW model
display list
Diff is drawn
* Executed on V-sync

Resources
(Expertise & availability)
(P.S. also points #2 & #3)

Resources
Expertise

Resources
Expertise Specifically designed HW&SW

Resources
- Expertise
Availability

Resources
- Expertise
Availability
Separate resource repo

Benefits
OnInvalidate()

Benefits
OnInvalidate() Refresh ONLY what was asked

Benefits
* Not always good

Benefits
* Not always good
Timing is better

Benefits
- OnInvalidate()
Res. expertise
Refresh ONLY what was asked
* Not always good
Timing is better

Benefits
- OnInvalidate()
Res. expertise
* Not always good
Timing is better
Faster

Benefits
- OnInvalidate()
Res. expertise
* Not always good
Timing is better
Faster
Better quality

Benefits
- OnInvalidate()
- Res. expertise
Res. avail.
* Not always good
Timing is better
Faster
Better quality

Benefits
- OnInvalidate()
Res. expertise
Res. avail.
* Not always good
Timing is better
Faster
Better quality
No waiting

Benefits
- OnInvalidate()
Res. expertise
Res. avail.
* Not always good
Timing is better
Faster
Better quality
No waiting (OK, less waiting)

Impediments
When could it hurt you?

Impediments
API avail.

Impediments
API avail. API < 11 N/A

Impediments
API >= 11 (3.x) Available, off

Impediments
API >= 11 (3.x) Available, off
API >= 14(4.x) Available, on

There’s a
disable API!

If it’s so
good?
W
hy
isn’t it
alw
ays on?

Impediments
- API avail.
Impediments
Increased RAM usage

Impediments
- API avail.
Impediments
Increased RAM usage
Not all op.s are supported

Impediments
- API avail.
Impediments
Increased RAM usage
Not all op.s are supported
Possible sick strange things!

Impediments
- API avail.
- Impediments
Examples
Possible sick strange things:

Impediments
- API avail.
- Impediments
Examples
Invisible UI elements

Impediments
- API avail.
- Impediments
Examples
Badly rendered pixels

Impediments
- API avail.
- Impediments
Examples
Possible sick strange things:
> Invisible UI elements
> Badly rendered pixels
> Exceptions

Analyzing
Know when you have a problem.

Safe!
(As in when are you...)

When is it safe?
When using only standard views

When is it safe?
- When using only standard views
When Min API level >= 17

What if that means nomore custom views?!?!

Check, test & verify
(Oh my!)

Check

Check DAC/guide/topics/graphics/hardware-accel.
html#drawing-support

- Check
Test

- Check
Test All the
devices!!!

- Check
Test
All the devices
Systrace

- Check
Test
All the devices
Systrace
Dumpsys gfxinfo

- Check
Test
All the devices
Systrace
Dumpsys gfxinfo
*Tracer

- Check
Test
** Ran Nachmany’s great session
https://www.youtube.com/watch?
v=aEFxqdPgHJk

Troubleshooting
Making the best of every situation

Reduce, reuse, recycle
(Things you need less of)

No. of views

No. of views
Less views

No. of views
Less views
Smaller display lists

No. of views
Less views
Smaller display lists
Less to draw

- No. of views
Overdraw

- No. of views
Overdraw
Never draw more than x2 the
no. of pixels

- No. of views
Overdraw
no. of pixels
Test:

- No. of views
Overdraw
no. of pixels
Test:
> Developer options

- No. of views
Overdraw
no. of pixels
Test:
Developer options
> Down. hierarchyViewer

- No. of views
Overdraw
no. of pixels
Test:
Developer options
Down. hierarchyViewer
(Screen layers)

- No. of views
Overdraw
no. of pixels
Fix:

- No. of views
Overdraw
no. of pixels
Fix:
> Merge/remove layers

- No. of views
Overdraw
no. of pixels
Fix:
Merge/remove layers
> Crop unseen pixels

- No. of views
Overdraw
Tip:

- No. of views
Overdraw
Tip:
Transparent pixels in
bitmaps count!

- No. of views
- Overdraw
New

- No. of views
- Overdraw
New
Objects in rendering func.

- No. of views
- Overdraw
New
Cause GC (very expensive)

- No. of views
- Overdraw
New
Examples:

- No. of views
- Overdraw
New
Examples:
> Paint

- No. of views
- Overdraw
New
Examples:
Paint
>Path

- No. of views
- Overdraw
- New
Modifications

- No. of views
- Overdraw
- New
Modifications
Shape/Circle/Path create a
new text. when altered

- No. of views
- Overdraw
- New
Modifications
Shape/Circle/Path create a
new text. when altered
Bitmaps are reloaded when
altered (to the GPU)

Use. Differently.
(Pro-tips for better usage)

Alpha anim.
Use. Differently.

Alpha anim.
Use. Differently.
Created in an off-screen
buffer

Alpha anim.
Use. Differently.
Created in an off-screen
buffer
Should be dealt in a hardware
layer type

- Alpha animation
Custom view
Use. Differently.

- Alpha animation
Custom view
Use. Differently.
private class PieView extends View {
public PieView(Context context) {
super(context);
if (!isInEditMode()) {
setLayerType(
View.
LAYER_TYPE_HARDWARE,
null);}}}

Set the scope
(One size does not fit all)

Application
Set the scope
<application android:hardwareAccelerated="true"
…
>

- Application
Activity
<application android:hardwareAccelerated="true">
<activity
android:hardwareAccelerated="false"
/>
</application>
Set the scope

- Application
- Activity
Window
Set the scope
getWindow().setFlags(
WindowManager.LayoutParams
.FLAG_HARDWARE_ACCELERATED,
.FLAG_HARDWARE_ACCELERATED
);

- Application
- Activity
Window
Set the scope
getWindow().setFlags(
.FLAG_HARDWARE_ACCELERATED,
.FLAG_HARDWARE_ACCELERATED
);
Note: You currently cannot disable
hardware acceleration at the window level.

- Application
- Activity
- Window
View&layer
Set the scope
myView.setLayerType(
View.LAYER_TYPE_SOFTWARE, null
);

- Application
- Activity
- Window
View&layer
Set the scope
myView.setLayerType(
View.LAYER_TYPE_SOFTWARE, null
);
Note:You currently cannot enable hardware
acceleration at the view level. View layers
have other functions besides disabling
hardware acceleration. See View layers for
more information about their uses.

Layer up
(All layers are NOT created equal)

None
Layer up
LAYER_TYPE_NONE

None
Layer up
LAYER_TYPE_NONE
not backed by any off screen buffer,
rendered in the SW model.

- None
Hardware
Layer up
LAYER_TYPE_HARDWARE

- None
Hardware
Layer up
LAYER_TYPE_HARDWARE
if HW accel. is on, layer is backed by HW
texture buffer and rendered in the HW
model, else it is the same as in the case of
LAYER_TYPE_SOFTWARE.

- None
Hardware
Layer up
Best for performance

- None
Hardware
Layer up
Best for performance:
> V-sync

- None
Hardware
Layer up
Best for performance:
V-sync
> Anim. added to the hardware
texture w/o redrawing.

- None
-Hardware
Software
Layer up
LAYER_TYPE_SOFTWARE - backed by a
Bitmap as if it was a buffer, rendered in the
SW model.

- None
-Hardware
Software
Layer up
Best for compatibility

- None
-Hardware
Software
Layer up
Best for compatibility:
> Min API < 11

- None
-Hardware
Software
Layer up
Best for compatibility:
Min API < 11
> Fixes different behaviour on
different devices (GPUs)

Be informed
(Which getter can’t be trusted)

View.isHardwareAccelerated()
Be informed

- View.isHardwareAccelerated()
Canvas.isHardwareAccelerated()
Be informed

- Canvas.isHardwareAccelerated()
Be informed

A view attached to a hardware accel. window can still be
drawn in the SW model
Be informed

A view attached to a hardware accel. window can still be
drawn in the SW model (like when it’s drawn to a bitmap
for caching).
Be informed

Summary
(What did we have here?)

Generally
Summery

Generally
Summery
HW accel is good but it has
issues

- Generally
GPUs
Summery
Are not created equally

- Generally
- GPUs
Less is more
Summery
Take only what you need

- Generally
- GPUs
- Less is more
Analyze&adapt
Summery
Wait for it...

- Generally
- GPUs
- Less is more
Analyze&adapt
Summery
ALWAYS!

“We should be building great
things. Things that Don’t yet
exist”

I Hope You Liked It
Thank you for listening
By Royi Benyossef (+royiby)

Learn to accel(erate)

Recommended

Recommended

More Related Content

Recently uploaded

Recently uploaded (9)

Featured

Featured (20)

Learn to accel(erate)