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Diffstat (limited to 'js/src/octane/navier-stokes.js')
-rw-r--r-- | js/src/octane/navier-stokes.js | 415 |
1 files changed, 415 insertions, 0 deletions
diff --git a/js/src/octane/navier-stokes.js b/js/src/octane/navier-stokes.js new file mode 100644 index 0000000000..6e21cb57ac --- /dev/null +++ b/js/src/octane/navier-stokes.js @@ -0,0 +1,415 @@ +/** + * 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], + [new Benchmark('NavierStokes', + true, + false, + 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++) { + 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++) { + 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); +} |