forked from Mirror/wren
64eccdd9be
Mainly to get rid of one top level directory. But this will also be useful when there are tests of the embedding API.
914 lines
25 KiB
Plaintext
914 lines
25 KiB
Plaintext
-- 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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--
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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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-- From: https://github.com/mraleph/deltablue.lua
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local planner
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--- O b j e c t M o d e l ---
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local function alert (...) print(...) end
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local OrderedCollection = class()
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function OrderedCollection:constructor()
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self.elms = {}
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end
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function OrderedCollection:add(elm)
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self.elms[#self.elms + 1] = elm
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end
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function OrderedCollection:at (index)
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return self.elms[index]
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end
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function OrderedCollection:size ()
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return #self.elms
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end
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function OrderedCollection:removeFirst ()
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local e = self.elms[#self.elms]
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self.elms[#self.elms] = nil
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return e
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end
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function OrderedCollection:remove (elm)
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local index = 0
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local skipped = 0
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for i = 1, #self.elms do
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local value = self.elms[i]
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if value ~= elm then
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self.elms[index] = value
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index = index + 1
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else
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skipped = skipped + 1
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end
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end
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local l = #self.elms
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for i = 1, skipped do self.elms[l - i + 1] = nil end
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end
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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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local Strength = class()
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function Strength:constructor(strengthValue, name)
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self.strengthValue = strengthValue
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self.name = name
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end
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function Strength.stronger (s1, s2)
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return s1.strengthValue < s2.strengthValue
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end
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function Strength.weaker (s1, s2)
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return s1.strengthValue > s2.strengthValue
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end
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function Strength.weakestOf (s1, s2)
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return Strength.weaker(s1, s2) and s1 or s2
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end
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function Strength.strongest (s1, s2)
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return Strength.stronger(s1, s2) and s1 or s2
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end
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function Strength:nextWeaker ()
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local v = self.strengthValue
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if v == 0 then return Strength.WEAKEST
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elseif v == 1 then return Strength.WEAK_DEFAULT
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elseif v == 2 then return Strength.NORMAL
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elseif v == 3 then return Strength.STRONG_DEFAULT
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elseif v == 4 then return Strength.PREFERRED
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elseif v == 5 then return Strength.REQUIRED
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end
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end
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-- Strength constants.
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Strength.REQUIRED = Strength.new(0, "required");
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Strength.STONG_PREFERRED = Strength.new(1, "strongPreferred");
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Strength.PREFERRED = Strength.new(2, "preferred");
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Strength.STRONG_DEFAULT = Strength.new(3, "strongDefault");
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Strength.NORMAL = Strength.new(4, "normal");
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Strength.WEAK_DEFAULT = Strength.new(5, "weakDefault");
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Strength.WEAKEST = Strength.new(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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local Constraint = class ()
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function Constraint:constructor(strength)
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self.strength = strength
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end
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--
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-- Activate this constraint and attempt to satisfy it.
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--
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function Constraint:addConstraint ()
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self:addToGraph()
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planner:incrementalAdd(self)
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end
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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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function Constraint:satisfy (mark)
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self:chooseMethod(mark)
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if not self:isSatisfied() then
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if self.strength == Strength.REQUIRED then
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alert("Could not satisfy a required constraint!")
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end
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return nil
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end
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self:markInputs(mark)
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local out = self:output()
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local overridden = out.determinedBy
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if overridden ~= nil then overridden:markUnsatisfied() end
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out.determinedBy = self
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if not planner:addPropagate(self, mark) then alert("Cycle encountered") end
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out.mark = mark
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return overridden
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end
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function Constraint:destroyConstraint ()
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if self:isSatisfied()
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then planner:incrementalRemove(self)
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else self:removeFromGraph()
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end
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end
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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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function Constraint:isInput ()
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return false
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end
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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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local UnaryConstraint = class(Constraint)
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function UnaryConstraint:constructor (v, strength)
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UnaryConstraint.super.constructor(self, strength)
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self.myOutput = v
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self.satisfied = false
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self:addConstraint()
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end
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--
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-- Adds this constraint to the constraint graph
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--
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function UnaryConstraint:addToGraph ()
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self.myOutput:addConstraint(self)
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self.satisfied = false
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end
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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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function UnaryConstraint:chooseMethod (mark)
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self.satisfied = (self.myOutput.mark ~= mark)
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and Strength.stronger(self.strength, self.myOutput.walkStrength);
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end
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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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function UnaryConstraint:isSatisfied ()
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return self.satisfied;
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end
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function UnaryConstraint:markInputs (mark)
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-- has no inputs
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end
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--
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-- Returns the current output variable.
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--
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function UnaryConstraint:output ()
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return self.myOutput
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end
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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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function UnaryConstraint:recalculate ()
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self.myOutput.walkStrength = self.strength
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self.myOutput.stay = not self:isInput()
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if self.myOutput.stay then
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self:execute() -- Stay optimization
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end
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end
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--
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-- Records that this constraint is unsatisfied
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--
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function UnaryConstraint:markUnsatisfied ()
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self.satisfied = false
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end
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function UnaryConstraint:inputsKnown ()
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return true
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end
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function UnaryConstraint:removeFromGraph ()
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if self.myOutput ~= nil then
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self.myOutput:removeConstraint(self)
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end
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self.satisfied = false
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end
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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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local StayConstraint = class(UnaryConstraint)
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function StayConstraint:constructor(v, str)
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StayConstraint.super.constructor(self, v, str)
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end
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function StayConstraint:execute ()
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-- Stay constraints do nothing
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end
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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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local EditConstraint = class (UnaryConstraint)
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function EditConstraint:constructor(v, str)
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EditConstraint.super.constructor(self, v, str)
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end
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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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function EditConstraint:isInput ()
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return true
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end
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function EditConstraint:execute ()
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-- Edit constraints do nothing
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end
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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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local Direction = {}
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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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local BinaryConstraint = class(Constraint)
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function BinaryConstraint:constructor(var1, var2, strength)
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BinaryConstraint.super.constructor(self, strength);
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self.v1 = var1
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self.v2 = var2
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self.direction = Direction.NONE
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self:addConstraint()
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end
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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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function BinaryConstraint:chooseMethod (mark)
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if self.v1.mark == mark then
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self.direction = (self.v2.mark ~= mark and Strength.stronger(self.strength, self.v2.walkStrength)) and Direction.FORWARD or Direction.NONE
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end
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if self.v2.mark == mark then
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self.direction = (self.v1.mark ~= mark and Strength.stronger(self.strength, self.v1.walkStrength)) and Direction.BACKWARD or Direction.NONE
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end
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if Strength.weaker(self.v1.walkStrength, self.v2.walkStrength) then
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self.direction = Strength.stronger(self.strength, self.v1.walkStrength) and Direction.BACKWARD or Direction.NONE
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else
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self.direction = Strength.stronger(self.strength, self.v2.walkStrength) and Direction.FORWARD or Direction.BACKWARD
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end
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end
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--
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-- Add this constraint to the constraint graph
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--
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function BinaryConstraint:addToGraph ()
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self.v1:addConstraint(self)
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self.v2:addConstraint(self)
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self.direction = Direction.NONE
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end
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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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function BinaryConstraint:isSatisfied ()
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return self.direction ~= Direction.NONE
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end
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--
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-- Mark the input variable with the given mark.
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--
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function BinaryConstraint:markInputs (mark)
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self:input().mark = mark
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end
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--
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-- Returns the current input variable
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--
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function BinaryConstraint:input ()
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return (self.direction == Direction.FORWARD) and self.v1 or self.v2
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end
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--
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-- Returns the current output variable
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--
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function BinaryConstraint:output ()
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return (self.direction == Direction.FORWARD) and self.v2 or self.v1
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end
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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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function BinaryConstraint:recalculate ()
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local ihn = self:input()
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local out = self:output()
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out.walkStrength = Strength.weakestOf(self.strength, ihn.walkStrength);
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out.stay = ihn.stay
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if out.stay then self:execute() end
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end
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--
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-- Record the fact that self constraint is unsatisfied.
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--
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function BinaryConstraint:markUnsatisfied ()
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self.direction = Direction.NONE
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end
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function BinaryConstraint:inputsKnown (mark)
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local i = self:input()
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return i.mark == mark or i.stay or i.determinedBy == nil
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end
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function BinaryConstraint:removeFromGraph ()
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if (self.v1 ~= nil) then self.v1:removeConstraint(self) end
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if (self.v2 ~= nil) then self.v2:removeConstraint(self) end
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self.direction = Direction.NONE
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end
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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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local ScaleConstraint = class (BinaryConstraint)
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function ScaleConstraint:constructor(src, scale, offset, dest, strength)
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self.direction = Direction.NONE
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self.scale = scale
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self.offset = offset
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ScaleConstraint.super.constructor(self, src, dest, strength)
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end
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--
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-- Adds this constraint to the constraint graph.
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--
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function ScaleConstraint:addToGraph ()
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ScaleConstraint.super.addToGraph(self)
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self.scale:addConstraint(self)
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self.offset:addConstraint(self)
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end
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function ScaleConstraint:removeFromGraph ()
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ScaleConstraint.super.removeFromGraph(self)
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if (self.scale ~= nil) then self.scale:removeConstraint(self) end
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if (self.offset ~= nil) then self.offset:removeConstraint(self) end
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end
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function ScaleConstraint:markInputs (mark)
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ScaleConstraint.super.markInputs(self, mark);
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self.offset.mark = mark
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self.scale.mark = mark
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end
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--
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-- Enforce this constraint. Assume that it is satisfied.
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--
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function ScaleConstraint:execute ()
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if self.direction == Direction.FORWARD then
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self.v2.value = self.v1.value * self.scale.value + self.offset.value
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else
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self.v1.value = (self.v2.value - self.offset.value) / self.scale.value
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end
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end
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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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function ScaleConstraint:recalculate ()
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local ihn = self:input()
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local out = self:output()
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out.walkStrength = Strength.weakestOf(self.strength, ihn.walkStrength)
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out.stay = ihn.stay and self.scale.stay and self.offset.stay
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if out.stay then self:execute() end
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end
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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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local EqualityConstraint = class (BinaryConstraint)
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function EqualityConstraint:constructor(var1, var2, strength)
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EqualityConstraint.super.constructor(self, var1, var2, strength)
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end
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--
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-- Enforce this constraint. Assume that it is satisfied.
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--
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function EqualityConstraint:execute ()
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self:output().value = self:input().value
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end
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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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local Variable = class ()
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function Variable:constructor(name, initialValue)
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self.value = initialValue or 0
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self.constraints = OrderedCollection.new()
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self.determinedBy = nil
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self.mark = 0
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self.walkStrength = Strength.WEAKEST
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self.stay = true
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self.name = name
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end
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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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function Variable:addConstraint (c)
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self.constraints:add(c)
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end
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--
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-- Removes all traces of c from this variable.
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--
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function Variable:removeConstraint (c)
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self.constraints:remove(c)
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if self.determinedBy == c then
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self.determinedBy = nil
|
|
end
|
|
end
|
|
|
|
--
|
|
-- P l a n n e r
|
|
--
|
|
|
|
--
|
|
-- The DeltaBlue planner
|
|
--
|
|
local Planner = class()
|
|
function Planner:constructor()
|
|
self.currentMark = 0
|
|
end
|
|
|
|
--
|
|
-- 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.
|
|
--
|
|
function Planner:incrementalAdd (c)
|
|
local mark = self:newMark()
|
|
local overridden = c:satisfy(mark)
|
|
while overridden ~= nil do
|
|
overridden = overridden:satisfy(mark)
|
|
end
|
|
end
|
|
|
|
--
|
|
-- 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.
|
|
--
|
|
function Planner:incrementalRemove (c)
|
|
local out = c:output()
|
|
c:markUnsatisfied()
|
|
c:removeFromGraph()
|
|
local unsatisfied = self:removePropagateFrom(out)
|
|
local strength = Strength.REQUIRED
|
|
repeat
|
|
for i = 1, unsatisfied:size() do
|
|
local u = unsatisfied:at(i)
|
|
if u.strength == strength then
|
|
self:incrementalAdd(u)
|
|
end
|
|
end
|
|
strength = strength:nextWeaker()
|
|
until strength == Strength.WEAKEST
|
|
end
|
|
|
|
--
|
|
-- Select a previously unused mark value.
|
|
--
|
|
function Planner:newMark ()
|
|
self.currentMark = self.currentMark + 1
|
|
return self.currentMark
|
|
end
|
|
|
|
--
|
|
-- 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.
|
|
--
|
|
local Plan -- FORWARD DECLARATION
|
|
function Planner:makePlan (sources)
|
|
local mark = self:newMark()
|
|
local plan = Plan.new()
|
|
local todo = sources
|
|
while todo:size() > 0 do
|
|
local c = todo:removeFirst()
|
|
if c:output().mark ~= mark and c:inputsKnown(mark) then
|
|
plan:addConstraint(c)
|
|
c:output().mark = mark
|
|
self:addConstraintsConsumingTo(c:output(), todo)
|
|
end
|
|
end
|
|
return plan
|
|
end
|
|
|
|
--
|
|
-- Extract a plan for resatisfying starting from the output of the
|
|
-- given constraints, usually a set of input constraints.
|
|
--
|
|
function Planner:extractPlanFromConstraints (constraints)
|
|
local sources = OrderedCollection.new()
|
|
for i = 1, constraints:size() do
|
|
local c = constraints:at(i)
|
|
if c:isInput() and c:isSatisfied() then
|
|
-- not in plan already and eligible for inclusion
|
|
sources:add(c)
|
|
end
|
|
end
|
|
return self:makePlan(sources)
|
|
end
|
|
|
|
--
|
|
-- 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.
|
|
--
|
|
function Planner:addPropagate (c, mark)
|
|
local todo = OrderedCollection.new()
|
|
todo:add(c)
|
|
while todo:size() > 0 do
|
|
local d = todo:removeFirst()
|
|
if d:output().mark == mark then
|
|
self:incrementalRemove(c)
|
|
return false
|
|
end
|
|
d:recalculate()
|
|
self:addConstraintsConsumingTo(d:output(), todo)
|
|
end
|
|
return true
|
|
end
|
|
|
|
|
|
--
|
|
-- 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.
|
|
--
|
|
function Planner:removePropagateFrom (out)
|
|
out.determinedBy = nil
|
|
out.walkStrength = Strength.WEAKEST
|
|
out.stay = true
|
|
local unsatisfied = OrderedCollection.new()
|
|
local todo = OrderedCollection.new()
|
|
todo:add(out)
|
|
while todo:size() > 0 do
|
|
local v = todo:removeFirst()
|
|
for i = 1, v.constraints:size() do
|
|
local c = v.constraints:at(i)
|
|
if not c:isSatisfied() then unsatisfied:add(c) end
|
|
end
|
|
local determining = v.determinedBy
|
|
for i = 1, v.constraints:size() do
|
|
local next = v.constraints:at(i);
|
|
if next ~= determining and next:isSatisfied() then
|
|
next:recalculate()
|
|
todo:add(next:output())
|
|
end
|
|
end
|
|
end
|
|
return unsatisfied
|
|
end
|
|
|
|
function Planner:addConstraintsConsumingTo (v, coll)
|
|
local determining = v.determinedBy
|
|
local cc = v.constraints
|
|
for i = 1, cc:size() do
|
|
local c = cc:at(i)
|
|
if c ~= determining and c:isSatisfied() then
|
|
coll:add(c)
|
|
end
|
|
end
|
|
end
|
|
|
|
--
|
|
-- 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.
|
|
--
|
|
Plan = class()
|
|
function Plan:constructor()
|
|
self.v = OrderedCollection.new()
|
|
end
|
|
|
|
function Plan:addConstraint (c)
|
|
self.v:add(c)
|
|
end
|
|
|
|
function Plan:size ()
|
|
return self.v:size()
|
|
end
|
|
|
|
function Plan:constraintAt (index)
|
|
return self.v:at(index)
|
|
end
|
|
|
|
function Plan:execute ()
|
|
for i = 1, self:size() do
|
|
local c = self:constraintAt(i)
|
|
c:execute()
|
|
end
|
|
end
|
|
|
|
--
|
|
-- 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.
|
|
--
|
|
local function chainTest(n)
|
|
planner = Planner.new()
|
|
local prev = nil
|
|
local first = nil
|
|
local last = nil
|
|
|
|
-- Build chain of n equality constraints
|
|
for i = 0, n do
|
|
local name = "v" .. i;
|
|
local v = Variable.new(name)
|
|
if prev ~= nil then EqualityConstraint.new(prev, v, Strength.REQUIRED) end
|
|
if i == 0 then first = v end
|
|
if i == n then last = v end
|
|
prev = v
|
|
end
|
|
|
|
StayConstraint.new(last, Strength.STRONG_DEFAULT)
|
|
local edit = EditConstraint.new(first, Strength.PREFERRED)
|
|
local edits = OrderedCollection.new()
|
|
edits:add(edit)
|
|
local plan = planner:extractPlanFromConstraints(edits)
|
|
for i = 0, 99 do
|
|
first.value = i
|
|
plan:execute()
|
|
if last.value ~= i then
|
|
alert("Chain test failed.")
|
|
end
|
|
end
|
|
end
|
|
|
|
local function change(v, newValue)
|
|
local edit = EditConstraint.new(v, Strength.PREFERRED)
|
|
local edits = OrderedCollection.new()
|
|
edits:add(edit)
|
|
local plan = planner:extractPlanFromConstraints(edits)
|
|
for i = 1, 10 do
|
|
v.value = newValue
|
|
plan:execute()
|
|
end
|
|
edit:destroyConstraint()
|
|
end
|
|
|
|
--
|
|
-- 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.
|
|
--
|
|
local function projectionTest(n)
|
|
planner = Planner.new();
|
|
local scale = Variable.new("scale", 10);
|
|
local offset = Variable.new("offset", 1000);
|
|
local src = nil
|
|
local dst = nil;
|
|
|
|
local dests = OrderedCollection.new();
|
|
for i = 0, n - 1 do
|
|
src = Variable.new("src" .. i, i);
|
|
dst = Variable.new("dst" .. i, i);
|
|
dests:add(dst);
|
|
StayConstraint.new(src, Strength.NORMAL);
|
|
ScaleConstraint.new(src, scale, offset, dst, Strength.REQUIRED);
|
|
end
|
|
|
|
change(src, 17)
|
|
if dst.value ~= 1170 then alert("Projection 1 failed") end
|
|
change(dst, 1050)
|
|
if src.value ~= 5 then alert("Projection 2 failed") end
|
|
change(scale, 5)
|
|
for i = 0, n - 2 do
|
|
if dests:at(i + 1).value ~= i * 5 + 1000 then
|
|
alert("Projection 3 failed")
|
|
end
|
|
end
|
|
change(offset, 2000)
|
|
for i = 0, n - 2 do
|
|
if dests:at(i + 1).value ~= i * 5 + 2000 then
|
|
alert("Projection 4 failed")
|
|
end
|
|
end
|
|
end
|
|
|
|
local function deltaBlue()
|
|
chainTest(100);
|
|
projectionTest(100);
|
|
end
|
|
|
|
DeltaBlue = BenchmarkSuite.new('DeltaBlue', 66118, {
|
|
Benchmark.new('DeltaBlue', deltaBlue)
|
|
}) |