remove prototype pathops code

experimental/Intersection/LineParameters.h

-/*
- * Copyright 2012 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-#include "DataTypes.h"
-
-// Sources
-// computer-aided design - volume 22 number 9 november 1990 pp 538 - 549
-// online at http://cagd.cs.byu.edu/~tom/papers/bezclip.pdf
-
-// This turns a line segment into a parameterized line, of the form
-// ax + by + c = 0
-// When a^2 + b^2 == 1, the line is normalized.
-// The distance to the line for (x, y) is d(x,y) = ax + by + c
-//
-// Note that the distances below are not necessarily normalized. To get the true
-// distance, it's necessary to either call normalize() after xxxEndPoints(), or
-// divide the result of xxxDistance() by sqrt(normalSquared())
-
-class LineParameters {
-public:
-    void cubicEndPoints(const Cubic& pts) {
-        cubicEndPoints(pts, 0, 3);
-    }
-
-    void cubicEndPoints(const Cubic& pts, int s, int e) {
-        a = approximately_pin(pts[s].y - pts[e].y);
-        b = approximately_pin(pts[e].x - pts[s].x);
-        c = pts[s].x * pts[e].y - pts[e].x * pts[s].y;
-    }
-
-    void lineEndPoints(const _Line& pts) {
-        a = approximately_pin(pts[0].y - pts[1].y);
-        b = approximately_pin(pts[1].x - pts[0].x);
-        c = pts[0].x * pts[1].y - pts[1].x * pts[0].y;
-    }
-
-    void quadEndPoints(const Quadratic& pts) {
-        quadEndPoints(pts, 0, 2);
-    }
-
-    void quadEndPoints(const Quadratic& pts, int s, int e) {
-        a = approximately_pin(pts[s].y - pts[e].y);
-        b = approximately_pin(pts[e].x - pts[s].x);
-        c = pts[s].x * pts[e].y - pts[e].x * pts[s].y;
-    }
-
-    double normalSquared() const {
-        return a * a + b * b;
-    }
-
-    bool normalize() {
-        double normal = sqrt(normalSquared());
-        if (approximately_zero(normal)) {
-            a = b = c = 0;
-            return false;
-        }
-        double reciprocal = 1 / normal;
-        a *= reciprocal;
-        b *= reciprocal;
-        c *= reciprocal;
-        return true;
-    }
-
-    void cubicDistanceY(const Cubic& pts, Cubic& distance) const {
-        double oneThird = 1 / 3.0;
-        for (int index = 0; index < 4; ++index) {
-            distance[index].x = index * oneThird;
-            distance[index].y = a * pts[index].x + b * pts[index].y + c;
-        }
-    }
-
-    void quadDistanceY(const Quadratic& pts, Quadratic& distance) const {
-        double oneHalf = 1 / 2.0;
-        for (int index = 0; index < 3; ++index) {
-            distance[index].x = index * oneHalf;
-            distance[index].y = a * pts[index].x + b * pts[index].y + c;
-        }
-    }
-
-    double controlPtDistance(const Cubic& pts, int index) const {
-        SkASSERT(index == 1 || index == 2);
-        return a * pts[index].x + b * pts[index].y + c;
-    }
-
-    double controlPtDistance(const Quadratic& pts) const {
-        return a * pts[1].x + b * pts[1].y + c;
-    }
-
-    double pointDistance(const _Point& pt) const {
-        return a * pt.x + b * pt.y + c;
-    }
-
-    double dx() const {
-        return b;
-    }
-
-    double dy() const {
-        return -a;
-    }
-
-private:
-    double a;
-    double b;
-    double c;
-};