From 33253a4baa6279f81a73425b49dfb6abe5f5416e Mon Sep 17 00:00:00 2001 From: Neil Fuller Date: Wed, 1 Oct 2014 11:55:10 +0100 Subject: Switch from FloatMath -> Math and Math.hypot where possible MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 --- .../WallpaperCropper/src/com/android/wallpapercropper/CropView.java | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'packages/WallpaperCropper') diff --git a/packages/WallpaperCropper/src/com/android/wallpapercropper/CropView.java b/packages/WallpaperCropper/src/com/android/wallpapercropper/CropView.java index c3ef302..4405207 100644 --- a/packages/WallpaperCropper/src/com/android/wallpapercropper/CropView.java +++ b/packages/WallpaperCropper/src/com/android/wallpapercropper/CropView.java @@ -21,7 +21,6 @@ import android.graphics.Matrix; import android.graphics.Point; import android.graphics.RectF; import android.util.AttributeSet; -import android.util.FloatMath; import android.view.MotionEvent; import android.view.ScaleGestureDetector; import android.view.ScaleGestureDetector.OnScaleGestureListener; @@ -300,12 +299,12 @@ public class CropView extends TiledImageView implements OnScaleGestureListener { adjustment[0] = (edges.right - getWidth()) / scale; } if (edges.top > 0) { - adjustment[1] = FloatMath.ceil(edges.top / scale); + adjustment[1] = (float) Math.ceil(edges.top / scale); } else if (edges.bottom < getHeight()) { adjustment[1] = (edges.bottom - getHeight()) / scale; } for (int dim = 0; dim <= 1; dim++) { - if (coef[dim] > 0) adjustment[dim] = FloatMath.ceil(adjustment[dim]); + if (coef[dim] > 0) adjustment[dim] = (float) Math.ceil(adjustment[dim]); } mInverseRotateMatrix.mapPoints(adjustment); -- cgit v1.1