| Index: experimental/Intersection/Extrema.cpp
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| diff --git a/experimental/Intersection/Extrema.cpp b/experimental/Intersection/Extrema.cpp
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| deleted file mode 100644
|
| index 7a41ddf77d24b114b69c0588a0c16b02ff3ab8ba..0000000000000000000000000000000000000000
|
| --- a/experimental/Intersection/Extrema.cpp
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| +++ /dev/null
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| @@ -1,81 +0,0 @@
|
| -/*
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| - * Copyright 2012 Google Inc.
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| - *
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| - * Use of this source code is governed by a BSD-style license that can be
|
| - * found in the LICENSE file.
|
| - */
|
| -#include "DataTypes.h"
|
| -#include "Extrema.h"
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| -
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| -static int validUnitDivide(double numer, double denom, double* ratio)
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| -{
|
| - if (numer < 0) {
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| - numer = -numer;
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| - denom = -denom;
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| - }
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| - if (denom == 0 || numer == 0 || numer >= denom)
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| - return 0;
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| - double r = numer / denom;
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| - if (r == 0) { // catch underflow if numer <<<< denom
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| - return 0;
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| - }
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| - *ratio = r;
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| - return 1;
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| -}
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| -
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| -/** From Numerical Recipes in C.
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| -
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| - Q = -1/2 (B + sign(B) sqrt[B*B - 4*A*C])
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| - x1 = Q / A
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| - x2 = C / Q
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| -*/
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| -static int findUnitQuadRoots(double A, double B, double C, double roots[2])
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| -{
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| - if (A == 0)
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| - return validUnitDivide(-C, B, roots);
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| -
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| - double* r = roots;
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| -
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| - double R = B*B - 4*A*C;
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| - if (R < 0) { // complex roots
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| - return 0;
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| - }
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| - R = sqrt(R);
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| -
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| - double Q = (B < 0) ? -(B-R)/2 : -(B+R)/2;
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| - r += validUnitDivide(Q, A, r);
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| - r += validUnitDivide(C, Q, r);
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| - if (r - roots == 2 && AlmostEqualUlps(roots[0], roots[1])) { // nearly-equal?
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| - r -= 1; // skip the double root
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| - }
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| - return (int)(r - roots);
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| -}
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| -
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| -/** Cubic'(t) = At^2 + Bt + C, where
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| - A = 3(-a + 3(b - c) + d)
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| - B = 6(a - 2b + c)
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| - C = 3(b - a)
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| - Solve for t, keeping only those that fit between 0 < t < 1
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| -*/
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| -int findExtrema(double a, double b, double c, double d, double tValues[2])
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| -{
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| - // we divide A,B,C by 3 to simplify
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| - double A = d - a + 3*(b - c);
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| - double B = 2*(a - b - b + c);
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| - double C = b - a;
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| -
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| - return findUnitQuadRoots(A, B, C, tValues);
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| -}
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| -
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| -/** Quad'(t) = At + B, where
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| - A = 2(a - 2b + c)
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| - B = 2(b - a)
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| - Solve for t, only if it fits between 0 < t < 1
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| -*/
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| -int findExtrema(double a, double b, double c, double tValue[1])
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| -{
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| - /* At + B == 0
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| - t = -B / A
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| - */
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| - return validUnitDivide(a - b, a - b - b + c, tValue);
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| -}
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|
|