Home | History | Annotate | Download | only in util 
      1 /*
      2  * Copyright 2012 AndroidPlot.com
      3  *
      4  *    Licensed under the Apache License, Version 2.0 (the "License");
      5  *    you may not use this file except in compliance with the License.
      6  *    You may obtain a copy of the License at
      7  *
      8  *        http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  *    Unless required by applicable law or agreed to in writing, software
     11  *    distributed under the License is distributed on an "AS IS" BASIS,
     12  *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  *    See the License for the specific language governing permissions and
     14  *    limitations under the License.
     15  */
     16 
     17 package com.androidplot.util;
     18 
     19 import android.graphics.Canvas;
     20 import android.graphics.Color;
     21 import android.graphics.Paint;
     22 import android.graphics.RectF;
     23 import com.androidplot.Plot;
     24 import com.androidplot.PlotListener;
     25 
     26 /**
     27  * !!! THIS CLASS IS STILL UNDER DEVELOPMENT AND MAY CONTAIN BUGS !!!
     28  * Gathers performance statistics from a Plot.  Instances of PlotStatistics
     29  * should never be added to more than one Plot, otherwise the statiscs will
     30  * be invalid.
     31  */
     32 public class PlotStatistics implements PlotListener {
     33     long minRenderTimeMs;
     34     long maxRenderTimeMs;
     35     long avgRenderTimeMs;
     36     long fps;
     37     long updateDelayMs;
     38 
     39 
     40     long longestRenderMs = 0;
     41     long shortestRenderMs = 0;
     42     long lastStart = 0;
     43     long lastLatency = 0;
     44     long lastAnnotation;
     45     long latencySamples = 0;
     46     long latencySum = 0;
     47     String annotationString = "";
     48 
     49     private Paint paint;
     50     {
     51         paint = new Paint();
     52         paint.setTextAlign(Paint.Align.CENTER);
     53         paint.setColor(Color.WHITE);
     54         paint.setTextSize(30);
     55         resetCounters();
     56     }
     57 
     58 
     59     private boolean annotatePlotEnabled;
     60 
     61 
     62 
     63     public PlotStatistics(long updateDelayMs, boolean annotatePlotEnabled) {
     64         this.updateDelayMs = updateDelayMs;
     65         this.annotatePlotEnabled = annotatePlotEnabled;
     66     }
     67 
     68     public void setAnnotatePlotEnabled(boolean enabled) {
     69         this.annotatePlotEnabled = enabled;
     70     }
     71 
     72     private void resetCounters() {
     73         longestRenderMs = 0;
     74         shortestRenderMs = 999999999;
     75         latencySamples = 0;
     76         latencySum = 0;
     77     }
     78 
     79     private void annotatePlot(Plot source, Canvas canvas) {
     80         long nowMs = System.currentTimeMillis();
     81         // throttle the update frequency:
     82         long msSinceUpdate = (nowMs - lastAnnotation);
     83         if(msSinceUpdate >= updateDelayMs) {
     84 
     85             float avgLatency = latencySamples > 0 ?  latencySum/latencySamples : 0;
     86             String overallFPS = String.format("%.2f", latencySamples > 0 ?  (1000f/msSinceUpdate) * latencySamples : 0);
     87             String potentialFPS = String.format("%.2f", latencySamples > 0 ? 1000f/avgLatency : 0);
     88             annotationString = "FPS (potential): " + potentialFPS + " FPS (actual): " + overallFPS + " Latency (ms) Avg: " + lastLatency + " \nMin: " + shortestRenderMs +
     89                     " Max: " + longestRenderMs;
     90             lastAnnotation = nowMs;
     91             resetCounters();
     92         }
     93         RectF r = source.getDisplayDimensions().canvasRect;
     94         if(annotatePlotEnabled) {
     95             canvas.drawText(annotationString, r.centerX(),  r.centerY(), paint);
     96         }
     97     }
     98 
     99     @Override
    100     public void onBeforeDraw(Plot source, Canvas canvas) {
    101         lastStart = System.currentTimeMillis();
    102     }
    103 
    104     @Override
    105     public void onAfterDraw(Plot source, Canvas canvas) {
    106         lastLatency = System.currentTimeMillis() - lastStart;
    107         if(lastLatency < shortestRenderMs) {
    108             shortestRenderMs = lastLatency;
    109         }
    110 
    111         if(lastLatency > longestRenderMs) {
    112             longestRenderMs = lastLatency;
    113         }
    114         latencySum += lastLatency;
    115         latencySamples++;
    116         annotatePlot(source, canvas);
    117     }
    118 }
    119