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-rw-r--r--gfx/skia/skia/src/pathops/SkPathOpsLine.cpp154
1 files changed, 154 insertions, 0 deletions
diff --git a/gfx/skia/skia/src/pathops/SkPathOpsLine.cpp b/gfx/skia/skia/src/pathops/SkPathOpsLine.cpp
new file mode 100644
index 0000000000..253f95b770
--- /dev/null
+++ b/gfx/skia/skia/src/pathops/SkPathOpsLine.cpp
@@ -0,0 +1,154 @@
+/*
+ * 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 "src/pathops/SkPathOpsLine.h"
+
+#include "src/pathops/SkPathOpsTypes.h"
+
+#include <cmath>
+#include <algorithm>
+
+SkDPoint SkDLine::ptAtT(double t) const {
+ if (0 == t) {
+ return fPts[0];
+ }
+ if (1 == t) {
+ return fPts[1];
+ }
+ double one_t = 1 - t;
+ SkDPoint result = { one_t * fPts[0].fX + t * fPts[1].fX, one_t * fPts[0].fY + t * fPts[1].fY };
+ return result;
+}
+
+double SkDLine::exactPoint(const SkDPoint& xy) const {
+ if (xy == fPts[0]) { // do cheapest test first
+ return 0;
+ }
+ if (xy == fPts[1]) {
+ return 1;
+ }
+ return -1;
+}
+
+double SkDLine::nearPoint(const SkDPoint& xy, bool* unequal) const {
+ if (!AlmostBetweenUlps(fPts[0].fX, xy.fX, fPts[1].fX)
+ || !AlmostBetweenUlps(fPts[0].fY, xy.fY, fPts[1].fY)) {
+ return -1;
+ }
+ // project a perpendicular ray from the point to the line; find the T on the line
+ SkDVector len = fPts[1] - fPts[0]; // the x/y magnitudes of the line
+ double denom = len.fX * len.fX + len.fY * len.fY; // see DLine intersectRay
+ SkDVector ab0 = xy - fPts[0];
+ double numer = len.fX * ab0.fX + ab0.fY * len.fY;
+ if (!between(0, numer, denom)) {
+ return -1;
+ }
+ if (!denom) {
+ return 0;
+ }
+ double t = numer / denom;
+ SkDPoint realPt = ptAtT(t);
+ double dist = realPt.distance(xy); // OPTIMIZATION: can we compare against distSq instead ?
+ // find the ordinal in the original line with the largest unsigned exponent
+ double tiniest = std::min(std::min(std::min(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
+ double largest = std::max(std::max(std::max(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
+ largest = std::max(largest, -tiniest);
+ if (!AlmostEqualUlps_Pin(largest, largest + dist)) { // is the dist within ULPS tolerance?
+ return -1;
+ }
+ if (unequal) {
+ *unequal = (float) largest != (float) (largest + dist);
+ }
+ t = SkPinT(t); // a looser pin breaks skpwww_lptemp_com_3
+ SkASSERT(between(0, t, 1));
+ return t;
+}
+
+bool SkDLine::nearRay(const SkDPoint& xy) const {
+ // project a perpendicular ray from the point to the line; find the T on the line
+ SkDVector len = fPts[1] - fPts[0]; // the x/y magnitudes of the line
+ double denom = len.fX * len.fX + len.fY * len.fY; // see DLine intersectRay
+ SkDVector ab0 = xy - fPts[0];
+ double numer = len.fX * ab0.fX + ab0.fY * len.fY;
+ double t = numer / denom;
+ SkDPoint realPt = ptAtT(t);
+ double dist = realPt.distance(xy); // OPTIMIZATION: can we compare against distSq instead ?
+ // find the ordinal in the original line with the largest unsigned exponent
+ double tiniest = std::min(std::min(std::min(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
+ double largest = std::max(std::max(std::max(fPts[0].fX, fPts[0].fY), fPts[1].fX), fPts[1].fY);
+ largest = std::max(largest, -tiniest);
+ return RoughlyEqualUlps(largest, largest + dist); // is the dist within ULPS tolerance?
+}
+
+double SkDLine::ExactPointH(const SkDPoint& xy, double left, double right, double y) {
+ if (xy.fY == y) {
+ if (xy.fX == left) {
+ return 0;
+ }
+ if (xy.fX == right) {
+ return 1;
+ }
+ }
+ return -1;
+}
+
+double SkDLine::NearPointH(const SkDPoint& xy, double left, double right, double y) {
+ if (!AlmostBequalUlps(xy.fY, y)) {
+ return -1;
+ }
+ if (!AlmostBetweenUlps(left, xy.fX, right)) {
+ return -1;
+ }
+ double t = (xy.fX - left) / (right - left);
+ t = SkPinT(t);
+ SkASSERT(between(0, t, 1));
+ double realPtX = (1 - t) * left + t * right;
+ SkDVector distU = {xy.fY - y, xy.fX - realPtX};
+ double distSq = distU.fX * distU.fX + distU.fY * distU.fY;
+ double dist = sqrt(distSq); // OPTIMIZATION: can we compare against distSq instead ?
+ double tiniest = std::min(std::min(y, left), right);
+ double largest = std::max(std::max(y, left), right);
+ largest = std::max(largest, -tiniest);
+ if (!AlmostEqualUlps(largest, largest + dist)) { // is the dist within ULPS tolerance?
+ return -1;
+ }
+ return t;
+}
+
+double SkDLine::ExactPointV(const SkDPoint& xy, double top, double bottom, double x) {
+ if (xy.fX == x) {
+ if (xy.fY == top) {
+ return 0;
+ }
+ if (xy.fY == bottom) {
+ return 1;
+ }
+ }
+ return -1;
+}
+
+double SkDLine::NearPointV(const SkDPoint& xy, double top, double bottom, double x) {
+ if (!AlmostBequalUlps(xy.fX, x)) {
+ return -1;
+ }
+ if (!AlmostBetweenUlps(top, xy.fY, bottom)) {
+ return -1;
+ }
+ double t = (xy.fY - top) / (bottom - top);
+ t = SkPinT(t);
+ SkASSERT(between(0, t, 1));
+ double realPtY = (1 - t) * top + t * bottom;
+ SkDVector distU = {xy.fX - x, xy.fY - realPtY};
+ double distSq = distU.fX * distU.fX + distU.fY * distU.fY;
+ double dist = sqrt(distSq); // OPTIMIZATION: can we compare against distSq instead ?
+ double tiniest = std::min(std::min(x, top), bottom);
+ double largest = std::max(std::max(x, top), bottom);
+ largest = std::max(largest, -tiniest);
+ if (!AlmostEqualUlps(largest, largest + dist)) { // is the dist within ULPS tolerance?
+ return -1;
+ }
+ return t;
+}