1 files changed, 21 insertions, 1 deletions
diff --git a/src/pathops/SkPathOpsLine.cpp b/src/pathops/SkPathOpsLine.cpp
index 70f2e12472..e4fc97bc61 100644
--- a/src/pathops/SkPathOpsLine.cpp
+++ b/src/pathops/SkPathOpsLine.cpp
@@ -6,6 +6,14 @@
  */
 #include "SkPathOpsLine.h"
 
+SkDLine SkDLine::subDivide(double t1, double t2) const {
+    SkDVector delta = tangent();
+    SkDLine dst = {{{
+            fPts[0].fX - t1 * delta.fX, fPts[0].fY - t1 * delta.fY}, {
+            fPts[0].fX - t2 * delta.fX, fPts[0].fY - t2 * delta.fY}}};
+    return dst;
+}
+
 // may have this below somewhere else already:
 // copying here because I thought it was clever
 
@@ -20,7 +28,6 @@
 //    Point with coordinates {float x, y;}
 //===================================================================
 
-// (only used by testing)
 // isLeft(): tests if a point is Left|On|Right of an infinite line.
 //    Input:  three points P0, P1, and P2
 //    Return: >0 for P2 left of the line through P0 and P1
@@ -103,6 +110,19 @@ bool SkDLine::nearRay(const SkDPoint& xy) const {
     return RoughlyEqualUlps(largest, largest + dist); // is the dist within ULPS tolerance?
 }
 
+// Returns true if a ray from (0,0) to (x1,y1) is coincident with a ray (0,0) to (x2,y2)
+// OPTIMIZE: a specialty routine could speed this up -- may not be called very often though
+bool SkDLine::NearRay(double x1, double y1, double x2, double y2) {
+    double denom1 = x1 * x1 + y1 * y1;
+    double denom2 = x2 * x2 + y2 * y2;
+    SkDLine line = {{{0, 0}, {x1, y1}}};
+    SkDPoint pt = {x2, y2};
+    if (denom2 > denom1) {
+        SkTSwap(line[1], pt);
+    }
+    return line.nearRay(pt);
+}
+
 double SkDLine::ExactPointH(const SkDPoint& xy, double left, double right, double y) {
     if (xy.fY == y) {
         if (xy.fX == left) {