| 33253a4baa6279f81a73425b49dfb6abe5f5416e |
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01-Oct-2014 |
Neil Fuller <nfuller@google.com> |
Switch from FloatMath -> Math and Math.hypot where possible
The motivation is an API change: FloatMath is going to be
deprecated and/or removed. Performance is not the goal of
this change.
That said...
Math is faster than FloatMath with AOT compilation.
While making the change, occurances of:
{Float}Math.sqrt(x * x + y * y) and
{Float}Math.sqrt({Float}Math.pow(x, 2) + {Float}Math.pow(y, 2))
have been replaced with:
{(float)} Math.hypot(x, y)
Right now there is no runtime intrinsic for hypot so is not faster
in all cases for AOT compilation:
Math.sqrt(x * x + y * y) is faster than Math.hypot(x, y) with
AOT, but all other combinations of FloatMath, use of pow() etc.
are slower than hypot().
hypot() has the advantage of being self documenting and
could be optimized in future. None of the behavior differences
around NaN and rounding appear to be important for the cases
looked at: they all assume results and arguments are in range
and usually the results are cast to float.
Different implementations measured on hammerhead / L:
AOT compiled:
[FloatMath.hypot(x, y)]
benchmark=Hypot_FloatMathHypot} 633.85 ns; σ=0.32 ns @ 3 trials
[FloatMath.sqrt(x*x + y*y)]
benchmark=Hypot_FloatMathSqrtMult} 684.17 ns; σ=4.83 ns @ 3 trials
[FloatMath.sqrt(FloatMath.pow(x, 2) + FloatMath.pow(y, 2))]
benchmark=Hypot_FloatMathSqrtPow} 1270.65 ns; σ=12.20 ns @ 6 trials
[(float) Math.hypot(x, y)]
benchmark=Hypot_MathHypot} 96.80 ns; σ=0.05 ns @ 3 trials
[(float) Math.sqrt(x*x + y*y)]
benchmark=Hypot_MathSqrtMult} 23.97 ns; σ=0.01 ns @ 3 trials
[(float) Math.sqrt(Math.pow(x, 2) + Math.pow(y, 2))]
benchmark=Hypot_MathSqrtPow} 156.19 ns; σ=0.12 ns @ 3 trials
Interpreter:
benchmark=Hypot_FloatMathHypot} 1180.54 ns; σ=5.13 ns @ 3 trials
benchmark=Hypot_FloatMathSqrtMult} 1121.05 ns; σ=3.80 ns @ 3 trials
benchmark=Hypot_FloatMathSqrtPow} 3327.14 ns; σ=7.33 ns @ 3 trials
benchmark=Hypot_MathHypot} 856.57 ns; σ=1.41 ns @ 3 trials
benchmark=Hypot_MathSqrtMult} 1028.92 ns; σ=9.11 ns @ 3 trials
benchmark=Hypot_MathSqrtPow} 2539.47 ns; σ=24.44 ns @ 3 trials
Bug: https://code.google.com/p/android/issues/detail?id=36199
Change-Id: I06c91f682095e627cb547d60d936ef87941be692
/frameworks/base/graphics/java/android/graphics/PointF.java
|
| 9f8af6546deb26d8bddb0c1b23d554fe5380b9d3 |
|
21-Nov-2012 |
Romain Guy <romainguy@google.com> |
Cleanup: add PointF.toString()/equals()/hashcode()
PointF was missing these methods found in Point.
This change also properly implements equals() and hashcode() for
Point to match the PointF implementations.
Change-Id: Ic97280fb9f8c7011d8a13103c67d6e898adf00c0
/frameworks/base/graphics/java/android/graphics/PointF.java
|
| 44bc17c6b517aef35a390c81b5aa79c4f284f744 |
|
21-Apr-2011 |
Dianne Hackborn <hackbod@google.com> |
Rework display size access.
Applications now get the display size from the window manager. No
behavior should be changed yet, this is just prep for some real
changes.
Change-Id: I2958a6660895c1cba2b670509600014e55ee9273
/frameworks/base/graphics/java/android/graphics/PointF.java
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| 9066cfe9886ac131c34d59ed0e2d287b0e3c0087 |
|
04-Mar-2009 |
The Android Open Source Project <initial-contribution@android.com> |
auto import from //depot/cupcake/@135843
/frameworks/base/graphics/java/android/graphics/PointF.java
|
| d83a98f4ce9cfa908f5c54bbd70f03eec07e7553 |
|
04-Mar-2009 |
The Android Open Source Project <initial-contribution@android.com> |
auto import from //depot/cupcake/@135843
/frameworks/base/graphics/java/android/graphics/PointF.java
|
| 54b6cfa9a9e5b861a9930af873580d6dc20f773c |
|
21-Oct-2008 |
The Android Open Source Project <initial-contribution@android.com> |
Initial Contribution
/frameworks/base/graphics/java/android/graphics/PointF.java
|