Review URL: http://codereview.chromium.org/3300031 git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5449 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
881 lines
25 KiB
JavaScript
881 lines
25 KiB
JavaScript
// Copyright 2008 the V8 project authors. All rights reserved.
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// Copyright 1996 John Maloney and Mario Wolczko.
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// This program is free software; you can redistribute it and/or modify
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// it under the terms of the GNU General Public License as published by
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// the Free Software Foundation; either version 2 of the License, or
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// (at your option) any later version.
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//
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// This program is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU General Public License for more details.
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//
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// You should have received a copy of the GNU General Public License
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// along with this program; if not, write to the Free Software
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// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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// This implementation of the DeltaBlue benchmark is derived
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// from the Smalltalk implementation by John Maloney and Mario
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// Wolczko. Some parts have been translated directly, whereas
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// others have been modified more aggresively to make it feel
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// more like a JavaScript program.
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var DeltaBlue = new BenchmarkSuite('DeltaBlue', 66118, [
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new Benchmark('DeltaBlue', deltaBlue)
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]);
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/**
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* A JavaScript implementation of the DeltaBlue constraint-solving
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* algorithm, as described in:
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*
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* "The DeltaBlue Algorithm: An Incremental Constraint Hierarchy Solver"
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* Bjorn N. Freeman-Benson and John Maloney
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* January 1990 Communications of the ACM,
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* also available as University of Washington TR 89-08-06.
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*
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* Beware: this benchmark is written in a grotesque style where
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* the constraint model is built by side-effects from constructors.
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* I've kept it this way to avoid deviating too much from the original
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* implementation.
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*/
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/* --- O b j e c t M o d e l --- */
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Object.prototype.inheritsFrom = function (shuper) {
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function Inheriter() { }
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Inheriter.prototype = shuper.prototype;
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this.prototype = new Inheriter();
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this.superConstructor = shuper;
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}
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function OrderedCollection() {
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this.elms = new Array();
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}
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OrderedCollection.prototype.add = function (elm) {
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this.elms.push(elm);
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}
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OrderedCollection.prototype.at = function (index) {
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return this.elms[index];
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}
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OrderedCollection.prototype.size = function () {
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return this.elms.length;
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}
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OrderedCollection.prototype.removeFirst = function () {
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return this.elms.pop();
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}
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OrderedCollection.prototype.remove = function (elm) {
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var index = 0, skipped = 0;
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for (var i = 0; i < this.elms.length; i++) {
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var value = this.elms[i];
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if (value != elm) {
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this.elms[index] = value;
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index++;
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} else {
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skipped++;
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}
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}
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for (var i = 0; i < skipped; i++)
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this.elms.pop();
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}
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/* --- *
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* S t r e n g t h
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* --- */
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/**
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* Strengths are used to measure the relative importance of constraints.
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* New strengths may be inserted in the strength hierarchy without
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* disrupting current constraints. Strengths cannot be created outside
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* this class, so pointer comparison can be used for value comparison.
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*/
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function Strength(strengthValue, name) {
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this.strengthValue = strengthValue;
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this.name = name;
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}
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Strength.stronger = function (s1, s2) {
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return s1.strengthValue < s2.strengthValue;
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}
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Strength.weaker = function (s1, s2) {
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return s1.strengthValue > s2.strengthValue;
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}
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Strength.weakestOf = function (s1, s2) {
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return this.weaker(s1, s2) ? s1 : s2;
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}
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Strength.strongest = function (s1, s2) {
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return this.stronger(s1, s2) ? s1 : s2;
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}
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Strength.prototype.nextWeaker = function () {
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switch (this.strengthValue) {
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case 0: return Strength.WEAKEST;
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case 1: return Strength.WEAK_DEFAULT;
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case 2: return Strength.NORMAL;
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case 3: return Strength.STRONG_DEFAULT;
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case 4: return Strength.PREFERRED;
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case 5: return Strength.REQUIRED;
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}
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}
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// Strength constants.
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Strength.REQUIRED = new Strength(0, "required");
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Strength.STONG_PREFERRED = new Strength(1, "strongPreferred");
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Strength.PREFERRED = new Strength(2, "preferred");
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Strength.STRONG_DEFAULT = new Strength(3, "strongDefault");
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Strength.NORMAL = new Strength(4, "normal");
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Strength.WEAK_DEFAULT = new Strength(5, "weakDefault");
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Strength.WEAKEST = new Strength(6, "weakest");
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/* --- *
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* C o n s t r a i n t
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* --- */
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/**
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* An abstract class representing a system-maintainable relationship
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* (or "constraint") between a set of variables. A constraint supplies
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* a strength instance variable; concrete subclasses provide a means
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* of storing the constrained variables and other information required
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* to represent a constraint.
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*/
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function Constraint(strength) {
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this.strength = strength;
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}
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/**
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* Activate this constraint and attempt to satisfy it.
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*/
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Constraint.prototype.addConstraint = function () {
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this.addToGraph();
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planner.incrementalAdd(this);
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}
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/**
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* Attempt to find a way to enforce this constraint. If successful,
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* record the solution, perhaps modifying the current dataflow
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* graph. Answer the constraint that this constraint overrides, if
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* there is one, or nil, if there isn't.
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* Assume: I am not already satisfied.
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*/
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Constraint.prototype.satisfy = function (mark) {
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this.chooseMethod(mark);
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if (!this.isSatisfied()) {
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if (this.strength == Strength.REQUIRED)
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alert("Could not satisfy a required constraint!");
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return null;
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}
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this.markInputs(mark);
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var out = this.output();
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var overridden = out.determinedBy;
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if (overridden != null) overridden.markUnsatisfied();
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out.determinedBy = this;
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if (!planner.addPropagate(this, mark))
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alert("Cycle encountered");
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out.mark = mark;
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return overridden;
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}
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Constraint.prototype.destroyConstraint = function () {
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if (this.isSatisfied()) planner.incrementalRemove(this);
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else this.removeFromGraph();
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}
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/**
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* Normal constraints are not input constraints. An input constraint
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* is one that depends on external state, such as the mouse, the
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* keybord, a clock, or some arbitraty piece of imperative code.
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*/
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Constraint.prototype.isInput = function () {
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return false;
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}
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/* --- *
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* U n a r y C o n s t r a i n t
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* --- */
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/**
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* Abstract superclass for constraints having a single possible output
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* variable.
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*/
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function UnaryConstraint(v, strength) {
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UnaryConstraint.superConstructor.call(this, strength);
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this.myOutput = v;
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this.satisfied = false;
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this.addConstraint();
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}
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UnaryConstraint.inheritsFrom(Constraint);
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/**
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* Adds this constraint to the constraint graph
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*/
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UnaryConstraint.prototype.addToGraph = function () {
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this.myOutput.addConstraint(this);
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this.satisfied = false;
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}
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/**
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* Decides if this constraint can be satisfied and records that
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* decision.
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*/
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UnaryConstraint.prototype.chooseMethod = function (mark) {
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this.satisfied = (this.myOutput.mark != mark)
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&& Strength.stronger(this.strength, this.myOutput.walkStrength);
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}
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/**
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* Returns true if this constraint is satisfied in the current solution.
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*/
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UnaryConstraint.prototype.isSatisfied = function () {
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return this.satisfied;
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}
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UnaryConstraint.prototype.markInputs = function (mark) {
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// has no inputs
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}
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/**
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* Returns the current output variable.
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*/
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UnaryConstraint.prototype.output = function () {
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return this.myOutput;
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}
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/**
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* Calculate the walkabout strength, the stay flag, and, if it is
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* 'stay', the value for the current output of this constraint. Assume
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* this constraint is satisfied.
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*/
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UnaryConstraint.prototype.recalculate = function () {
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this.myOutput.walkStrength = this.strength;
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this.myOutput.stay = !this.isInput();
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if (this.myOutput.stay) this.execute(); // Stay optimization
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}
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/**
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* Records that this constraint is unsatisfied
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*/
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UnaryConstraint.prototype.markUnsatisfied = function () {
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this.satisfied = false;
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}
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UnaryConstraint.prototype.inputsKnown = function () {
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return true;
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}
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UnaryConstraint.prototype.removeFromGraph = function () {
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if (this.myOutput != null) this.myOutput.removeConstraint(this);
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this.satisfied = false;
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}
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/* --- *
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* S t a y C o n s t r a i n t
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* --- */
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/**
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* Variables that should, with some level of preference, stay the same.
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* Planners may exploit the fact that instances, if satisfied, will not
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* change their output during plan execution. This is called "stay
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* optimization".
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*/
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function StayConstraint(v, str) {
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StayConstraint.superConstructor.call(this, v, str);
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}
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StayConstraint.inheritsFrom(UnaryConstraint);
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StayConstraint.prototype.execute = function () {
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// Stay constraints do nothing
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}
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/* --- *
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* E d i t C o n s t r a i n t
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* --- */
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/**
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* A unary input constraint used to mark a variable that the client
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* wishes to change.
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*/
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function EditConstraint(v, str) {
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EditConstraint.superConstructor.call(this, v, str);
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}
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EditConstraint.inheritsFrom(UnaryConstraint);
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/**
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* Edits indicate that a variable is to be changed by imperative code.
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*/
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EditConstraint.prototype.isInput = function () {
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return true;
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}
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EditConstraint.prototype.execute = function () {
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// Edit constraints do nothing
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}
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/* --- *
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* B i n a r y C o n s t r a i n t
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* --- */
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var Direction = new Object();
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Direction.NONE = 0;
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Direction.FORWARD = 1;
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Direction.BACKWARD = -1;
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/**
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* Abstract superclass for constraints having two possible output
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* variables.
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*/
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function BinaryConstraint(var1, var2, strength) {
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BinaryConstraint.superConstructor.call(this, strength);
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this.v1 = var1;
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this.v2 = var2;
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this.direction = Direction.NONE;
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this.addConstraint();
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}
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BinaryConstraint.inheritsFrom(Constraint);
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/**
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* Decides if this constraint can be satisfied and which way it
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* should flow based on the relative strength of the variables related,
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* and record that decision.
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*/
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BinaryConstraint.prototype.chooseMethod = function (mark) {
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if (this.v1.mark == mark) {
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this.direction = (this.v2.mark != mark && Strength.stronger(this.strength, this.v2.walkStrength))
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? Direction.FORWARD
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: Direction.NONE;
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}
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if (this.v2.mark == mark) {
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this.direction = (this.v1.mark != mark && Strength.stronger(this.strength, this.v1.walkStrength))
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? Direction.BACKWARD
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: Direction.NONE;
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}
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if (Strength.weaker(this.v1.walkStrength, this.v2.walkStrength)) {
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this.direction = Strength.stronger(this.strength, this.v1.walkStrength)
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? Direction.BACKWARD
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: Direction.NONE;
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} else {
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this.direction = Strength.stronger(this.strength, this.v2.walkStrength)
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? Direction.FORWARD
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: Direction.BACKWARD
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}
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}
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/**
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* Add this constraint to the constraint graph
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*/
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BinaryConstraint.prototype.addToGraph = function () {
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this.v1.addConstraint(this);
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this.v2.addConstraint(this);
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this.direction = Direction.NONE;
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}
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/**
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* Answer true if this constraint is satisfied in the current solution.
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*/
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BinaryConstraint.prototype.isSatisfied = function () {
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return this.direction != Direction.NONE;
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}
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/**
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* Mark the input variable with the given mark.
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*/
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BinaryConstraint.prototype.markInputs = function (mark) {
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this.input().mark = mark;
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}
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/**
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* Returns the current input variable
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*/
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BinaryConstraint.prototype.input = function () {
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return (this.direction == Direction.FORWARD) ? this.v1 : this.v2;
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}
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/**
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* Returns the current output variable
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*/
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BinaryConstraint.prototype.output = function () {
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return (this.direction == Direction.FORWARD) ? this.v2 : this.v1;
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}
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/**
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* Calculate the walkabout strength, the stay flag, and, if it is
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* 'stay', the value for the current output of this
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* constraint. Assume this constraint is satisfied.
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*/
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BinaryConstraint.prototype.recalculate = function () {
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var ihn = this.input(), out = this.output();
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out.walkStrength = Strength.weakestOf(this.strength, ihn.walkStrength);
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out.stay = ihn.stay;
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if (out.stay) this.execute();
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}
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/**
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* Record the fact that this constraint is unsatisfied.
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*/
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BinaryConstraint.prototype.markUnsatisfied = function () {
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this.direction = Direction.NONE;
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}
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BinaryConstraint.prototype.inputsKnown = function (mark) {
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var i = this.input();
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return i.mark == mark || i.stay || i.determinedBy == null;
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}
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BinaryConstraint.prototype.removeFromGraph = function () {
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if (this.v1 != null) this.v1.removeConstraint(this);
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if (this.v2 != null) this.v2.removeConstraint(this);
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this.direction = Direction.NONE;
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}
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/* --- *
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* S c a l e C o n s t r a i n t
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* --- */
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/**
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* Relates two variables by the linear scaling relationship: "v2 =
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* (v1 * scale) + offset". Either v1 or v2 may be changed to maintain
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* this relationship but the scale factor and offset are considered
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* read-only.
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*/
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function ScaleConstraint(src, scale, offset, dest, strength) {
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this.direction = Direction.NONE;
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this.scale = scale;
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this.offset = offset;
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ScaleConstraint.superConstructor.call(this, src, dest, strength);
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}
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ScaleConstraint.inheritsFrom(BinaryConstraint);
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/**
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* Adds this constraint to the constraint graph.
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*/
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ScaleConstraint.prototype.addToGraph = function () {
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ScaleConstraint.superConstructor.prototype.addToGraph.call(this);
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this.scale.addConstraint(this);
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this.offset.addConstraint(this);
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}
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ScaleConstraint.prototype.removeFromGraph = function () {
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ScaleConstraint.superConstructor.prototype.removeFromGraph.call(this);
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if (this.scale != null) this.scale.removeConstraint(this);
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if (this.offset != null) this.offset.removeConstraint(this);
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}
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ScaleConstraint.prototype.markInputs = function (mark) {
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ScaleConstraint.superConstructor.prototype.markInputs.call(this, mark);
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this.scale.mark = this.offset.mark = mark;
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}
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/**
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* Enforce this constraint. Assume that it is satisfied.
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*/
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ScaleConstraint.prototype.execute = function () {
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if (this.direction == Direction.FORWARD) {
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this.v2.value = this.v1.value * this.scale.value + this.offset.value;
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} else {
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this.v1.value = (this.v2.value - this.offset.value) / this.scale.value;
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}
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}
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/**
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* Calculate the walkabout strength, the stay flag, and, if it is
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* 'stay', the value for the current output of this constraint. Assume
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* this constraint is satisfied.
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*/
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ScaleConstraint.prototype.recalculate = function () {
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var ihn = this.input(), out = this.output();
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out.walkStrength = Strength.weakestOf(this.strength, ihn.walkStrength);
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out.stay = ihn.stay && this.scale.stay && this.offset.stay;
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if (out.stay) this.execute();
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}
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/* --- *
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* E q u a l i t y C o n s t r a i n t
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* --- */
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/**
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* Constrains two variables to have the same value.
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*/
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function EqualityConstraint(var1, var2, strength) {
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EqualityConstraint.superConstructor.call(this, var1, var2, strength);
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}
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EqualityConstraint.inheritsFrom(BinaryConstraint);
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/**
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* Enforce this constraint. Assume that it is satisfied.
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*/
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EqualityConstraint.prototype.execute = function () {
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this.output().value = this.input().value;
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}
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/* --- *
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* V a r i a b l e
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* --- */
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/**
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* A constrained variable. In addition to its value, it maintain the
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* structure of the constraint graph, the current dataflow graph, and
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* various parameters of interest to the DeltaBlue incremental
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* constraint solver.
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**/
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function Variable(name, initialValue) {
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this.value = initialValue || 0;
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this.constraints = new OrderedCollection();
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this.determinedBy = null;
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this.mark = 0;
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this.walkStrength = Strength.WEAKEST;
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this.stay = true;
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this.name = name;
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}
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/**
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* Add the given constraint to the set of all constraints that refer
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* this variable.
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*/
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Variable.prototype.addConstraint = function (c) {
|
|
this.constraints.add(c);
|
|
}
|
|
|
|
/**
|
|
* Removes all traces of c from this variable.
|
|
*/
|
|
Variable.prototype.removeConstraint = function (c) {
|
|
this.constraints.remove(c);
|
|
if (this.determinedBy == c) this.determinedBy = null;
|
|
}
|
|
|
|
/* --- *
|
|
* P l a n n e r
|
|
* --- */
|
|
|
|
/**
|
|
* The DeltaBlue planner
|
|
*/
|
|
function Planner() {
|
|
this.currentMark = 0;
|
|
}
|
|
|
|
/**
|
|
* Attempt to satisfy the given constraint and, if successful,
|
|
* incrementally update the dataflow graph. Details: If satifying
|
|
* the constraint is successful, it may override a weaker constraint
|
|
* on its output. The algorithm attempts to resatisfy that
|
|
* constraint using some other method. This process is repeated
|
|
* until either a) it reaches a variable that was not previously
|
|
* determined by any constraint or b) it reaches a constraint that
|
|
* is too weak to be satisfied using any of its methods. The
|
|
* variables of constraints that have been processed are marked with
|
|
* a unique mark value so that we know where we've been. This allows
|
|
* the algorithm to avoid getting into an infinite loop even if the
|
|
* constraint graph has an inadvertent cycle.
|
|
*/
|
|
Planner.prototype.incrementalAdd = function (c) {
|
|
var mark = this.newMark();
|
|
var overridden = c.satisfy(mark);
|
|
while (overridden != null)
|
|
overridden = overridden.satisfy(mark);
|
|
}
|
|
|
|
/**
|
|
* Entry point for retracting a constraint. Remove the given
|
|
* constraint and incrementally update the dataflow graph.
|
|
* Details: Retracting the given constraint may allow some currently
|
|
* unsatisfiable downstream constraint to be satisfied. We therefore collect
|
|
* a list of unsatisfied downstream constraints and attempt to
|
|
* satisfy each one in turn. This list is traversed by constraint
|
|
* strength, strongest first, as a heuristic for avoiding
|
|
* unnecessarily adding and then overriding weak constraints.
|
|
* Assume: c is satisfied.
|
|
*/
|
|
Planner.prototype.incrementalRemove = function (c) {
|
|
var out = c.output();
|
|
c.markUnsatisfied();
|
|
c.removeFromGraph();
|
|
var unsatisfied = this.removePropagateFrom(out);
|
|
var strength = Strength.REQUIRED;
|
|
do {
|
|
for (var i = 0; i < unsatisfied.size(); i++) {
|
|
var u = unsatisfied.at(i);
|
|
if (u.strength == strength)
|
|
this.incrementalAdd(u);
|
|
}
|
|
strength = strength.nextWeaker();
|
|
} while (strength != Strength.WEAKEST);
|
|
}
|
|
|
|
/**
|
|
* Select a previously unused mark value.
|
|
*/
|
|
Planner.prototype.newMark = function () {
|
|
return ++this.currentMark;
|
|
}
|
|
|
|
/**
|
|
* Extract a plan for resatisfaction starting from the given source
|
|
* constraints, usually a set of input constraints. This method
|
|
* assumes that stay optimization is desired; the plan will contain
|
|
* only constraints whose output variables are not stay. Constraints
|
|
* that do no computation, such as stay and edit constraints, are
|
|
* not included in the plan.
|
|
* Details: The outputs of a constraint are marked when it is added
|
|
* to the plan under construction. A constraint may be appended to
|
|
* the plan when all its input variables are known. A variable is
|
|
* known if either a) the variable is marked (indicating that has
|
|
* been computed by a constraint appearing earlier in the plan), b)
|
|
* the variable is 'stay' (i.e. it is a constant at plan execution
|
|
* time), or c) the variable is not determined by any
|
|
* constraint. The last provision is for past states of history
|
|
* variables, which are not stay but which are also not computed by
|
|
* any constraint.
|
|
* Assume: sources are all satisfied.
|
|
*/
|
|
Planner.prototype.makePlan = function (sources) {
|
|
var mark = this.newMark();
|
|
var plan = new Plan();
|
|
var todo = sources;
|
|
while (todo.size() > 0) {
|
|
var c = todo.removeFirst();
|
|
if (c.output().mark != mark && c.inputsKnown(mark)) {
|
|
plan.addConstraint(c);
|
|
c.output().mark = mark;
|
|
this.addConstraintsConsumingTo(c.output(), todo);
|
|
}
|
|
}
|
|
return plan;
|
|
}
|
|
|
|
/**
|
|
* Extract a plan for resatisfying starting from the output of the
|
|
* given constraints, usually a set of input constraints.
|
|
*/
|
|
Planner.prototype.extractPlanFromConstraints = function (constraints) {
|
|
var sources = new OrderedCollection();
|
|
for (var i = 0; i < constraints.size(); i++) {
|
|
var c = constraints.at(i);
|
|
if (c.isInput() && c.isSatisfied())
|
|
// not in plan already and eligible for inclusion
|
|
sources.add(c);
|
|
}
|
|
return this.makePlan(sources);
|
|
}
|
|
|
|
/**
|
|
* Recompute the walkabout strengths and stay flags of all variables
|
|
* downstream of the given constraint and recompute the actual
|
|
* values of all variables whose stay flag is true. If a cycle is
|
|
* detected, remove the given constraint and answer
|
|
* false. Otherwise, answer true.
|
|
* Details: Cycles are detected when a marked variable is
|
|
* encountered downstream of the given constraint. The sender is
|
|
* assumed to have marked the inputs of the given constraint with
|
|
* the given mark. Thus, encountering a marked node downstream of
|
|
* the output constraint means that there is a path from the
|
|
* constraint's output to one of its inputs.
|
|
*/
|
|
Planner.prototype.addPropagate = function (c, mark) {
|
|
var todo = new OrderedCollection();
|
|
todo.add(c);
|
|
while (todo.size() > 0) {
|
|
var d = todo.removeFirst();
|
|
if (d.output().mark == mark) {
|
|
this.incrementalRemove(c);
|
|
return false;
|
|
}
|
|
d.recalculate();
|
|
this.addConstraintsConsumingTo(d.output(), todo);
|
|
}
|
|
return true;
|
|
}
|
|
|
|
|
|
/**
|
|
* Update the walkabout strengths and stay flags of all variables
|
|
* downstream of the given constraint. Answer a collection of
|
|
* unsatisfied constraints sorted in order of decreasing strength.
|
|
*/
|
|
Planner.prototype.removePropagateFrom = function (out) {
|
|
out.determinedBy = null;
|
|
out.walkStrength = Strength.WEAKEST;
|
|
out.stay = true;
|
|
var unsatisfied = new OrderedCollection();
|
|
var todo = new OrderedCollection();
|
|
todo.add(out);
|
|
while (todo.size() > 0) {
|
|
var v = todo.removeFirst();
|
|
for (var i = 0; i < v.constraints.size(); i++) {
|
|
var c = v.constraints.at(i);
|
|
if (!c.isSatisfied())
|
|
unsatisfied.add(c);
|
|
}
|
|
var determining = v.determinedBy;
|
|
for (var i = 0; i < v.constraints.size(); i++) {
|
|
var next = v.constraints.at(i);
|
|
if (next != determining && next.isSatisfied()) {
|
|
next.recalculate();
|
|
todo.add(next.output());
|
|
}
|
|
}
|
|
}
|
|
return unsatisfied;
|
|
}
|
|
|
|
Planner.prototype.addConstraintsConsumingTo = function (v, coll) {
|
|
var determining = v.determinedBy;
|
|
var cc = v.constraints;
|
|
for (var i = 0; i < cc.size(); i++) {
|
|
var c = cc.at(i);
|
|
if (c != determining && c.isSatisfied())
|
|
coll.add(c);
|
|
}
|
|
}
|
|
|
|
/* --- *
|
|
* P l a n
|
|
* --- */
|
|
|
|
/**
|
|
* A Plan is an ordered list of constraints to be executed in sequence
|
|
* to resatisfy all currently satisfiable constraints in the face of
|
|
* one or more changing inputs.
|
|
*/
|
|
function Plan() {
|
|
this.v = new OrderedCollection();
|
|
}
|
|
|
|
Plan.prototype.addConstraint = function (c) {
|
|
this.v.add(c);
|
|
}
|
|
|
|
Plan.prototype.size = function () {
|
|
return this.v.size();
|
|
}
|
|
|
|
Plan.prototype.constraintAt = function (index) {
|
|
return this.v.at(index);
|
|
}
|
|
|
|
Plan.prototype.execute = function () {
|
|
for (var i = 0; i < this.size(); i++) {
|
|
var c = this.constraintAt(i);
|
|
c.execute();
|
|
}
|
|
}
|
|
|
|
/* --- *
|
|
* M a i n
|
|
* --- */
|
|
|
|
/**
|
|
* This is the standard DeltaBlue benchmark. A long chain of equality
|
|
* constraints is constructed with a stay constraint on one end. An
|
|
* edit constraint is then added to the opposite end and the time is
|
|
* measured for adding and removing this constraint, and extracting
|
|
* and executing a constraint satisfaction plan. There are two cases.
|
|
* In case 1, the added constraint is stronger than the stay
|
|
* constraint and values must propagate down the entire length of the
|
|
* chain. In case 2, the added constraint is weaker than the stay
|
|
* constraint so it cannot be accomodated. The cost in this case is,
|
|
* of course, very low. Typical situations lie somewhere between these
|
|
* two extremes.
|
|
*/
|
|
function chainTest(n) {
|
|
planner = new Planner();
|
|
var prev = null, first = null, last = null;
|
|
|
|
// Build chain of n equality constraints
|
|
for (var i = 0; i <= n; i++) {
|
|
var name = "v" + i;
|
|
var v = new Variable(name);
|
|
if (prev != null)
|
|
new EqualityConstraint(prev, v, Strength.REQUIRED);
|
|
if (i == 0) first = v;
|
|
if (i == n) last = v;
|
|
prev = v;
|
|
}
|
|
|
|
new StayConstraint(last, Strength.STRONG_DEFAULT);
|
|
var edit = new EditConstraint(first, Strength.PREFERRED);
|
|
var edits = new OrderedCollection();
|
|
edits.add(edit);
|
|
var plan = planner.extractPlanFromConstraints(edits);
|
|
for (var i = 0; i < 100; i++) {
|
|
first.value = i;
|
|
plan.execute();
|
|
if (last.value != i)
|
|
alert("Chain test failed.");
|
|
}
|
|
}
|
|
|
|
/**
|
|
* This test constructs a two sets of variables related to each
|
|
* other by a simple linear transformation (scale and offset). The
|
|
* time is measured to change a variable on either side of the
|
|
* mapping and to change the scale and offset factors.
|
|
*/
|
|
function projectionTest(n) {
|
|
planner = new Planner();
|
|
var scale = new Variable("scale", 10);
|
|
var offset = new Variable("offset", 1000);
|
|
var src = null, dst = null;
|
|
|
|
var dests = new OrderedCollection();
|
|
for (var i = 0; i < n; i++) {
|
|
src = new Variable("src" + i, i);
|
|
dst = new Variable("dst" + i, i);
|
|
dests.add(dst);
|
|
new StayConstraint(src, Strength.NORMAL);
|
|
new ScaleConstraint(src, scale, offset, dst, Strength.REQUIRED);
|
|
}
|
|
|
|
change(src, 17);
|
|
if (dst.value != 1170) alert("Projection 1 failed");
|
|
change(dst, 1050);
|
|
if (src.value != 5) alert("Projection 2 failed");
|
|
change(scale, 5);
|
|
for (var i = 0; i < n - 1; i++) {
|
|
if (dests.at(i).value != i * 5 + 1000)
|
|
alert("Projection 3 failed");
|
|
}
|
|
change(offset, 2000);
|
|
for (var i = 0; i < n - 1; i++) {
|
|
if (dests.at(i).value != i * 5 + 2000)
|
|
alert("Projection 4 failed");
|
|
}
|
|
}
|
|
|
|
function change(v, newValue) {
|
|
var edit = new EditConstraint(v, Strength.PREFERRED);
|
|
var edits = new OrderedCollection();
|
|
edits.add(edit);
|
|
var plan = planner.extractPlanFromConstraints(edits);
|
|
for (var i = 0; i < 10; i++) {
|
|
v.value = newValue;
|
|
plan.execute();
|
|
}
|
|
edit.destroyConstraint();
|
|
}
|
|
|
|
// Global variable holding the current planner.
|
|
var planner = null;
|
|
|
|
function deltaBlue() {
|
|
chainTest(100);
|
|
projectionTest(100);
|
|
}
|