ChakraCore/test/benchmarks/Octane_Closure/navier-stokes.js

// Copyright 2013 the V8 project authors. All rights reserved.
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
//       notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
//       copyright notice, this list of conditions and the following
//       disclaimer in the documentation and/or other materials provided
//       with the distribution.
//     * Neither the name of Google Inc. nor the names of its
//       contributors may be used to endorse or promote products derived
//       from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.


// Performance.now is used in latency benchmarks, the fallback is Date.now.
var performance = performance || {};
performance.now = (function() {
  return performance.now       ||
         performance.mozNow    ||
         performance.msNow     ||
         performance.oNow      ||
         performance.webkitNow ||
         Date.now;
})();

// Simple framework for running the benchmark suites and
// computing a score based on the timing measurements.


// A benchmark has a name (string) and a function that will be run to
// do the performance measurement. The optional setup and tearDown
// arguments are functions that will be invoked before and after
// running the benchmark, but the running time of these functions will
// not be accounted for in the benchmark score.
function Benchmark(name, doWarmup, doDeterministic, deterministicIterations, 
                   run, setup, tearDown, rmsResult, minIterations) {
  this.name = name;
  this.doWarmup = doWarmup;
  this.doDeterministic = doDeterministic;
  this.deterministicIterations = deterministicIterations;
  this.run = run;
  this.Setup = setup ? setup : function() { };
  this.TearDown = tearDown ? tearDown : function() { };
  this.rmsResult = rmsResult ? rmsResult : null; 
  this.minIterations = minIterations ? minIterations : 32;
}


// Benchmark results hold the benchmark and the measured time used to
// run the benchmark. The benchmark score is computed later once a
// full benchmark suite has run to completion. If latency is set to 0
// then there is no latency score for this benchmark.
function BenchmarkResult(benchmark, time, latency) {
  this.benchmark = benchmark;
  this.time = time;
  this.latency = latency;
}


// Automatically convert results to numbers. Used by the geometric
// mean computation.
BenchmarkResult.prototype.valueOf = function() {
  return this.time;
}


// Suites of benchmarks consist of a name and the set of benchmarks in
// addition to the reference timing that the final score will be based
// on. This way, all scores are relative to a reference run and higher
// scores implies better performance.
function BenchmarkSuite(name, reference, benchmarks) {
  this.name = name;
  this.reference = reference;
  this.benchmarks = benchmarks;
  BenchmarkSuite.suites.push(this);
}


// Keep track of all declared benchmark suites.
BenchmarkSuite.suites = [];

// Scores are not comparable across versions. Bump the version if
// you're making changes that will affect that scores, e.g. if you add
// a new benchmark or change an existing one.
BenchmarkSuite.version = '9';


// Defines global benchsuite running mode that overrides benchmark suite 
// behavior. Intended to be set by the benchmark driver. Undefined 
// values here allow a benchmark to define behaviour itself.
BenchmarkSuite.config = {
  doWarmup: undefined,
  doDeterministic: undefined
};


// Override the alert function to throw an exception instead.
alert = function(s) {
  throw "Alert called with argument: " + s;
};


// To make the benchmark results predictable, we replace Math.random
// with a 100% deterministic alternative.
BenchmarkSuite.ResetRNG = function() {
  Math.random = (function() {
    var seed = 49734321;
    return function() {
      // Robert Jenkins' 32 bit integer hash function.
      seed = ((seed + 0x7ed55d16) + (seed << 12))  & 0xffffffff;
      seed = ((seed ^ 0xc761c23c) ^ (seed >>> 19)) & 0xffffffff;
      seed = ((seed + 0x165667b1) + (seed << 5))   & 0xffffffff;
      seed = ((seed + 0xd3a2646c) ^ (seed << 9))   & 0xffffffff;
      seed = ((seed + 0xfd7046c5) + (seed << 3))   & 0xffffffff;
      seed = ((seed ^ 0xb55a4f09) ^ (seed >>> 16)) & 0xffffffff;
      return (seed & 0xfffffff) / 0x10000000;
    };
  })();
}


// Runs all registered benchmark suites and optionally yields between
// each individual benchmark to avoid running for too long in the
// context of browsers. Once done, the final score is reported to the
// runner.
BenchmarkSuite.RunSuites = function(runner, skipBenchmarks) {
  skipBenchmarks = typeof skipBenchmarks === 'undefined' ? [] : skipBenchmarks;
  var continuation = null;
  var suites = BenchmarkSuite.suites;
  var length = suites.length;
  BenchmarkSuite.scores = [];
  var index = 0;
  function RunStep() {
    while (continuation || index < length) {
      if (continuation) {
        continuation = continuation();
      } else {
        var suite = suites[index++];
        if (runner.NotifyStart) runner.NotifyStart(suite.name);
        if (skipBenchmarks.indexOf(suite.name) > -1) {
          suite.NotifySkipped(runner);
        } else {
          continuation = suite.RunStep(runner);
        }
      }
      if (continuation && typeof window != 'undefined' && window.setTimeout) {
        window.setTimeout(RunStep, 25);
        return;
      }
    }

    // show final result
    if (runner.NotifyScore) {
      var score = BenchmarkSuite.GeometricMean(BenchmarkSuite.scores);
      var formatted = BenchmarkSuite.FormatScore(100 * score);
      runner.NotifyScore(formatted);
    }
  }
  RunStep();
}


// Counts the total number of registered benchmarks. Useful for
// showing progress as a percentage.
BenchmarkSuite.CountBenchmarks = function() {
  var result = 0;
  var suites = BenchmarkSuite.suites;
  for (var i = 0; i < suites.length; i++) {
    result += suites[i].benchmarks.length;
  }
  return result;
}


// Computes the geometric mean of a set of numbers.
BenchmarkSuite.GeometricMean = function(numbers) {
  var log = 0;
  for (var i = 0; i < numbers.length; i++) {
    log += Math.log(numbers[i]);
  }
  return Math.pow(Math.E, log / numbers.length);
}


// Computes the geometric mean of a set of throughput time measurements.
BenchmarkSuite.GeometricMeanTime = function(measurements) {
  var log = 0;
  for (var i = 0; i < measurements.length; i++) {
    log += Math.log(measurements[i].time);
  }
  return Math.pow(Math.E, log / measurements.length);
}


// Computes the geometric mean of a set of rms measurements.
BenchmarkSuite.GeometricMeanLatency = function(measurements) {
  var log = 0;
  var hasLatencyResult = false;
  for (var i = 0; i < measurements.length; i++) {
    if (measurements[i].latency != 0) {
      log += Math.log(measurements[i].latency);
      hasLatencyResult = true;
    }
  }
  if (hasLatencyResult) {
    return Math.pow(Math.E, log / measurements.length);
  } else {
    return 0;
  }
}


// Converts a score value to a string with at least three significant
// digits.
BenchmarkSuite.FormatScore = function(value) {
  if (value > 100) {
    return value.toFixed(0);
  } else {
    return value.toPrecision(3);
  }
}

// Notifies the runner that we're done running a single benchmark in
// the benchmark suite. This can be useful to report progress.
BenchmarkSuite.prototype.NotifyStep = function(result) {
  this.results.push(result);
  if (this.runner.NotifyStep) this.runner.NotifyStep(result.benchmark.name);
}


// Notifies the runner that we're done with running a suite and that
// we have a result which can be reported to the user if needed.
BenchmarkSuite.prototype.NotifyResult = function() {
  var mean = BenchmarkSuite.GeometricMeanTime(this.results);
  var score = this.reference[0] / mean;
  BenchmarkSuite.scores.push(score);
  if (this.runner.NotifyResult) {
    var formatted = BenchmarkSuite.FormatScore(100 * score);
    this.runner.NotifyResult(this.name, formatted);
  }
  if (this.reference.length == 2) {
    var meanLatency = BenchmarkSuite.GeometricMeanLatency(this.results);
    if (meanLatency != 0) {
      var scoreLatency = this.reference[1] / meanLatency;
      BenchmarkSuite.scores.push(scoreLatency);
      if (this.runner.NotifyResult) {
        var formattedLatency = BenchmarkSuite.FormatScore(100 * scoreLatency)
        this.runner.NotifyResult(this.name + "Latency", formattedLatency);
      }
    }
  }
}


BenchmarkSuite.prototype.NotifySkipped = function(runner) {
  BenchmarkSuite.scores.push(1);  // push default reference score.
  if (runner.NotifyResult) {
    runner.NotifyResult(this.name, "Skipped");
  }
}


// Notifies the runner that running a benchmark resulted in an error.
BenchmarkSuite.prototype.NotifyError = function(error) {
  if (this.runner.NotifyError) {
    this.runner.NotifyError(this.name, error);
  }
  if (this.runner.NotifyStep) {
    this.runner.NotifyStep(this.name);
  }
}


// Runs a single benchmark for at least a second and computes the
// average time it takes to run a single iteration.
BenchmarkSuite.prototype.RunSingleBenchmark = function(benchmark, data) {
  var config = BenchmarkSuite.config;
  var doWarmup = config.doWarmup !== undefined 
                 ? config.doWarmup 
                 : benchmark.doWarmup;
  var doDeterministic = config.doDeterministic !== undefined 
                        ? config.doDeterministic 
                        : benchmark.doDeterministic;

  function Measure(data) {
    var elapsed = 0;
    var start = new Date();
  
  // Run either for 1 second or for the number of iterations specified
  // by minIterations, depending on the config flag doDeterministic.
    for (var i = 0; (doDeterministic ? 
      i<benchmark.deterministicIterations : elapsed < 1000); i++) {
      benchmark.run();
      elapsed = new Date() - start;
    }
    if (data != null) {
      data.runs += i;
      data.elapsed += elapsed;
    }
  }

  // Sets up data in order to skip or not the warmup phase.
  if (!doWarmup && data == null) {
    data = { runs: 0, elapsed: 0 };
  }

  if (data == null) {
    Measure(null);
    return { runs: 0, elapsed: 0 };
  } else {
    Measure(data);
    // If we've run too few iterations, we continue for another second.
    if (data.runs < benchmark.minIterations) return data;
    var usec = (data.elapsed * 1000) / data.runs;
    var rms = (benchmark.rmsResult != null) ? benchmark.rmsResult() : 0;
    this.NotifyStep(new BenchmarkResult(benchmark, usec, rms));
    return null;
  }
}


// This function starts running a suite, but stops between each
// individual benchmark in the suite and returns a continuation
// function which can be invoked to run the next benchmark. Once the
// last benchmark has been executed, null is returned.
BenchmarkSuite.prototype.RunStep = function(runner) {
  BenchmarkSuite.ResetRNG();
  this.results = [];
  this.runner = runner;
  var length = this.benchmarks.length;
  var index = 0;
  var suite = this;
  var data;

  // Run the setup, the actual benchmark, and the tear down in three
  // separate steps to allow the framework to yield between any of the
  // steps.

  function RunNextSetup() {
    if (index < length) {
      try {
        suite.benchmarks[index].Setup();
      } catch (e) {
        suite.NotifyError(e);
        return null;
      }
      return RunNextBenchmark;
    }
    suite.NotifyResult();
    return null;
  }

  function RunNextBenchmark() {
    try {
      data = suite.RunSingleBenchmark(suite.benchmarks[index], data);
    } catch (e) {
      suite.NotifyError(e);
      return null;
    }
    // If data is null, we're done with this benchmark.
    return (data == null) ? RunNextTearDown : RunNextBenchmark();
  }

  function RunNextTearDown() {
    try {
      suite.benchmarks[index++].TearDown();
    } catch (e) {
      suite.NotifyError(e);
      return null;
    }
    return RunNextSetup;
  }

  // Start out running the setup.
  return RunNextSetup();
}
/**
 * Copyright 2013 the V8 project authors. All rights reserved.
 * Copyright 2009 Oliver Hunt <http://nerget.com>
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use,
 * copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following
 * conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 * Update 10/21/2013: fixed loop variables at line 119
 */

var NavierStokes = new BenchmarkSuite('NavierStokes', [1484000, 2000],
                                      [new Benchmark('NavierStokes',
                                                     true,
                                                     true,
                                                     180,
                                                     runNavierStokes,
                                                     setupNavierStokes,
                                                     tearDownNavierStokes,
                                                     null,
                                                     16)]);

var solver = null;
var nsFrameCounter = 0;

function runNavierStokes()
{
    solver.update();
    nsFrameCounter++;

    if(nsFrameCounter==15)
        checkResult(solver.getDens());
}

function checkResult(dens) {

    this.result = 0;
    for (var i=7000;i<7100;i++) {
        this.result+=~~((dens[i]*10));
    }

    if (this.result!=77) {
        throw(new Error("checksum failed"));
    }
}

function setupNavierStokes()
{
    solver = new FluidField(null);
    solver.setResolution(128, 128);
    solver.setIterations(20);
    solver.setDisplayFunction(function(){});
    solver.setUICallback(prepareFrame);
    solver.reset();
}

function tearDownNavierStokes()
{
    solver = null;
}

function addPoints(field) {
    var n = 64;
    for (var i = 1; i <= n; i++) {
        field.setVelocity(i, i, n, n);
        field.setDensity(i, i, 5);
        field.setVelocity(i, n - i, -n, -n);
        field.setDensity(i, n - i, 20);
        field.setVelocity(128 - i, n + i, -n, -n);
        field.setDensity(128 - i, n + i, 30);
    }
}

var framesTillAddingPoints = 0;
var framesBetweenAddingPoints = 5;

function prepareFrame(field)
{
    if (framesTillAddingPoints == 0) {
        addPoints(field);
        framesTillAddingPoints = framesBetweenAddingPoints;
        framesBetweenAddingPoints++;
    } else {
        framesTillAddingPoints--;
    }
}

// Code from Oliver Hunt (http://nerget.com/fluidSim/pressure.js) starts here.
function FluidField(canvas) {
    function addFields(x, s, dt)
    {
        for (var i=0; i<size ; i++ ) x[i] += dt*s[i];
    }

    function set_bnd(b, x)
    {
        if (b===1) {
            for (var i = 1; i <= width; i++) {
                x[i] =  x[i + rowSize];
                x[i + (height+1) *rowSize] = x[i + height * rowSize];
            }

            for (var j = 1; j <= height; j++) {
                x[j * rowSize] = -x[1 + j * rowSize];
                x[(width + 1) + j * rowSize] = -x[width + j * rowSize];
            }
        } else if (b === 2) {
            for (var i = 1; i <= width; i++) {
                x[i] = -x[i + rowSize];
                x[i + (height + 1) * rowSize] = -x[i + height * rowSize];
            }

            for (var j = 1; j <= height; j++) { // site 1
                x[j * rowSize] =  x[1 + j * rowSize];
                x[(width + 1) + j * rowSize] =  x[width + j * rowSize];
            }
        } else {
            for (var i = 1; i <= width; i++) {
                x[i] =  x[i + rowSize];
                x[i + (height + 1) * rowSize] = x[i + height * rowSize];
            }

            for (var j = 1; j <= height; j++) { // site 2
                x[j * rowSize] =  x[1 + j * rowSize];
                x[(width + 1) + j * rowSize] =  x[width + j * rowSize];
            }
        }
        var maxEdge = (height + 1) * rowSize;
        x[0]                 = 0.5 * (x[1] + x[rowSize]);
        x[maxEdge]           = 0.5 * (x[1 + maxEdge] + x[height * rowSize]);
        x[(width+1)]         = 0.5 * (x[width] + x[(width + 1) + rowSize]);
        x[(width+1)+maxEdge] = 0.5 * (x[width + maxEdge] + x[(width + 1) + height * rowSize]);
    }

    function lin_solve(b, x, x0, a, c)
    {
        if (a === 0 && c === 1) {
            for (var j=1 ; j<=height; j++) {
                var currentRow = j * rowSize;
                ++currentRow;
                for (var i = 0; i < width; i++) {
                    x[currentRow] = x0[currentRow];
                    ++currentRow;
                }
            }
            set_bnd(b, x);
        } else {
            var invC = 1 / c;
            for (var k=0 ; k<iterations; k++) {
                for (var j=1 ; j<=height; j++) {
                    var lastRow = (j - 1) * rowSize;
                    var currentRow = j * rowSize;
                    var nextRow = (j + 1) * rowSize;
                    var lastX = x[currentRow];
                    ++currentRow;
                    for (var i=1; i<=width; i++)
                        lastX = x[currentRow] = (x0[currentRow] + a*(lastX+x[++currentRow]+x[++lastRow]+x[++nextRow])) * invC;
                }
                set_bnd(b, x);
            }
        }
    }

    function diffuse(b, x, x0, dt)
    {
        var a = 0;
        lin_solve(b, x, x0, a, 1 + 4*a);
    }

    function lin_solve2(x, x0, y, y0, a, c)
    {
        if (a === 0 && c === 1) {
            for (var j=1 ; j <= height; j++) {
                var currentRow = j * rowSize;
                ++currentRow;
                for (var i = 0; i < width; i++) {
                    x[currentRow] = x0[currentRow];
                    y[currentRow] = y0[currentRow];
                    ++currentRow;
                }
            }
            set_bnd(1, x);
            set_bnd(2, y);
        } else {
            var invC = 1/c;
            for (var k=0 ; k<iterations; k++) {
                for (var j=1 ; j <= height; j++) {
                    var lastRow = (j - 1) * rowSize;
                    var currentRow = j * rowSize;
                    var nextRow = (j + 1) * rowSize;
                    var lastX = x[currentRow];
                    var lastY = y[currentRow];
                    ++currentRow;
                    for (var i = 1; i <= width; i++) {
                        lastX = x[currentRow] = (x0[currentRow] + a * (lastX + x[currentRow] + x[lastRow] + x[nextRow])) * invC;
                        lastY = y[currentRow] = (y0[currentRow] + a * (lastY + y[++currentRow] + y[++lastRow] + y[++nextRow])) * invC;
                    }
                }
                set_bnd(1, x);
                set_bnd(2, y);
            }
        }
    }

    function diffuse2(x, x0, y, y0, dt)
    {
        var a = 0;
        lin_solve2(x, x0, y, y0, a, 1 + 4 * a);
    }

    function advect(b, d, d0, u, v, dt)
    {
        var Wdt0 = dt * width;
        var Hdt0 = dt * height;
        var Wp5 = width + 0.5;
        var Hp5 = height + 0.5;
        for (var j = 1; j<= height; j++) {
            var pos = j * rowSize;
            for (var i = 1; i <= width; i++) {
                var x = i - Wdt0 * u[++pos];
                var y = j - Hdt0 * v[pos];
                if (x < 0.5)
                    x = 0.5;
                else if (x > Wp5)
                    x = Wp5;
                var i0 = x | 0;
                var i1 = i0 + 1;
                if (y < 0.5)
                    y = 0.5;
                else if (y > Hp5)
                    y = Hp5;
                var j0 = y | 0;
                var j1 = j0 + 1;
                var s1 = x - i0;
                var s0 = 1 - s1;
                var t1 = y - j0;
                var t0 = 1 - t1;
                var row1 = j0 * rowSize;
                var row2 = j1 * rowSize;
                d[pos] = s0 * (t0 * d0[i0 + row1] + t1 * d0[i0 + row2]) + s1 * (t0 * d0[i1 + row1] + t1 * d0[i1 + row2]);
            }
        }
        set_bnd(b, d);
    }

    function project(u, v, p, div)
    {
        var h = -0.5 / Math.sqrt(width * height);
        for (var j = 1 ; j <= height; j++ ) {
            var row = j * rowSize;
            var previousRow = (j - 1) * rowSize;
            var prevValue = row - 1;
            var currentRow = row;
            var nextValue = row + 1;
            var nextRow = (j + 1) * rowSize;
            for (var i = 1; i <= width; i++ ) {
                div[++currentRow] = h * (u[++nextValue] - u[++prevValue] + v[++nextRow] - v[++previousRow]);
                p[currentRow] = 0;
            }
        }
        set_bnd(0, div);
        set_bnd(0, p);

        lin_solve(0, p, div, 1, 4 );
        var wScale = 0.5 * width;
        var hScale = 0.5 * height;
        for (var j = 1; j<= height; j++ ) {
            var prevPos = j * rowSize - 1;
            var currentPos = j * rowSize;
            var nextPos = j * rowSize + 1;
            var prevRow = (j - 1) * rowSize;
            var currentRow = j * rowSize;
            var nextRow = (j + 1) * rowSize;

            for (var i = 1; i<= width; i++) {
                u[++currentPos] -= wScale * (p[++nextPos] - p[++prevPos]);
                v[currentPos]   -= hScale * (p[++nextRow] - p[++prevRow]);
            }
        }
        set_bnd(1, u);
        set_bnd(2, v);
    }

    function dens_step(x, x0, u, v, dt)
    {
        addFields(x, x0, dt);
        diffuse(0, x0, x, dt );
        advect(0, x, x0, u, v, dt );
    }

    function vel_step(u, v, u0, v0, dt)
    {
        addFields(u, u0, dt );
        addFields(v, v0, dt );
        var temp = u0; u0 = u; u = temp;
        var temp = v0; v0 = v; v = temp;
        diffuse2(u,u0,v,v0, dt);
        project(u, v, u0, v0);
        var temp = u0; u0 = u; u = temp;
        var temp = v0; v0 = v; v = temp;
        advect(1, u, u0, u0, v0, dt);
        advect(2, v, v0, u0, v0, dt);
        project(u, v, u0, v0 );
    }
    var uiCallback = function(d,u,v) {};

    function Field(dens, u, v) {
        // Just exposing the fields here rather than using accessors is a measurable win during display (maybe 5%)
        // but makes the code ugly.
        this.setDensity = function(x, y, d) {
             dens[(x + 1) + (y + 1) * rowSize] = d;
        }
        this.getDensity = function(x, y) {
             return dens[(x + 1) + (y + 1) * rowSize];
        }
        this.setVelocity = function(x, y, xv, yv) {
             u[(x + 1) + (y + 1) * rowSize] = xv;
             v[(x + 1) + (y + 1) * rowSize] = yv;
        }
        this.getXVelocity = function(x, y) {
             return u[(x + 1) + (y + 1) * rowSize];
        }
        this.getYVelocity = function(x, y) {
             return v[(x + 1) + (y + 1) * rowSize];
        }
        this.width = function() { return width; }
        this.height = function() { return height; }
    }
    function queryUI(d, u, v)
    {
        for (var i = 0; i < size; i++)
            u[i] = v[i] = d[i] = 0.0;
        uiCallback(new Field(d, u, v));
    }

    this.update = function () {
        queryUI(dens_prev, u_prev, v_prev);
        vel_step(u, v, u_prev, v_prev, dt);
        dens_step(dens, dens_prev, u, v, dt);
        displayFunc(new Field(dens, u, v));
    }
    this.setDisplayFunction = function(func) {
        displayFunc = func;
    }

    this.iterations = function() { return iterations; }
    this.setIterations = function(iters) {
        if (iters > 0 && iters <= 100)
           iterations = iters;
    }
    this.setUICallback = function(callback) {
        uiCallback = callback;
    }
    var iterations = 10;
    var visc = 0.5;
    var dt = 0.1;
    var dens;
    var dens_prev;
    var u;
    var u_prev;
    var v;
    var v_prev;
    var width;
    var height;
    var rowSize;
    var size;
    var displayFunc;
    function reset()
    {
        rowSize = width + 2;
        size = (width+2)*(height+2);
        dens = new Array(size);
        dens_prev = new Array(size);
        u = new Array(size);
        u_prev = new Array(size);
        v = new Array(size);
        v_prev = new Array(size);
        for (var i = 0; i < size; i++)
            dens_prev[i] = u_prev[i] = v_prev[i] = dens[i] = u[i] = v[i] = 0;
    }
    this.reset = reset;
    this.getDens = function()
    {
        return dens;
    }
    this.setResolution = function (hRes, wRes)
    {
        var res = wRes * hRes;
        if (res > 0 && res < 1000000 && (wRes != width || hRes != height)) {
            width = wRes;
            height = hRes;
            reset();
            return true;
        }
        return false;
    }
    this.setResolution(64, 64);
}
////////////////////////////////////////////////////////////////////////////////
// Runner
////////////////////////////////////////////////////////////////////////////////

var success = true;

function NotifyStart(name) {
}

function NotifyError(name, error) {
    WScript.Echo(name + " : ERROR : " + error.stack);
    success = false;
}

function NotifyResult(name, score) {
    if (success) {
        WScript.Echo("### SCORE:", score);
    }
}

function NotifyScore(score) {
}

BenchmarkSuite.RunSuites({
    NotifyStart: NotifyStart,
    NotifyError: NotifyError,
    NotifyResult: NotifyResult,
    NotifyScore: NotifyScore
});