blob: f71bd111861ea8f5b5241ea1a87dbdb94e1a3260 [file] [log] [blame]
/*
* Copyright (C) Rich Moore. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY CONTRIBUTORS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/////. Start CORDIC
var AG_CONST = 0.6072529350;
function FIXED(X)
{
return X * 65536.0;
}
function FLOAT(X)
{
return X / 65536.0;
}
function DEG2RAD(X)
{
return 0.017453 * (X);
}
var Angles = [
FIXED(45.0), FIXED(26.565), FIXED(14.0362), FIXED(7.12502),
FIXED(3.57633), FIXED(1.78991), FIXED(0.895174), FIXED(0.447614),
FIXED(0.223811), FIXED(0.111906), FIXED(0.055953),
FIXED(0.027977)
];
var Target = 28.027;
function cordicsincos(Target) {
var X;
var Y;
var TargetAngle;
var CurrAngle;
var Step;
X = FIXED(AG_CONST); /* AG_CONST * cos(0) */
Y = 0; /* AG_CONST * sin(0) */
TargetAngle = FIXED(Target);
CurrAngle = 0;
for (Step = 0; Step < 12; Step++) {
var NewX;
if (TargetAngle > CurrAngle) {
NewX = X - (Y >> Step);
Y = (X >> Step) + Y;
X = NewX;
CurrAngle += Angles[Step];
} else {
NewX = X + (Y >> Step);
Y = -(X >> Step) + Y;
X = NewX;
CurrAngle -= Angles[Step];
}
}
return FLOAT(X) * FLOAT(Y);
}
///// End CORDIC
var total = 0;
function cordic( runs ) {
var start = new Date();
for ( var i = 0 ; i < runs ; i++ ) {
total += cordicsincos(Target);
}
var end = new Date();
return end.getTime() - start.getTime();
}
cordic(25000);
var expected = 10362.570468755888;
if (total != expected)
throw "ERROR: bad result: expected " + expected + " but got " + total;