Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 274 insertions, 0 deletions

diff --git a/layout/painting/DashedCornerFinder.h b/layout/painting/DashedCornerFinder.h
new file mode 100644
index 0000000000..3a409d19f7
--- /dev/null
+++ b/layout/painting/DashedCornerFinder.h
@@ -0,0 +1,274 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_DashedCornerFinder_h_
+#define mozilla_DashedCornerFinder_h_
+
+#include "mozilla/gfx/2D.h"
+#include "mozilla/gfx/BezierUtils.h"
+
+namespace mozilla {
+
+// Calculate {OuterT_i, InnerT_i} for each 1 < i < n, that
+//   (OuterL_i + InnerL_i) / 2 == dashLength * (W_i + W_{i-1}) / 2
+// where
+//   OuterP_i: OuterCurve(OuterT_i)
+//   InnerP_i: InnerCurve(OuterT_i)
+//   OuterL_i: Elliptic arc length between OuterP_i - OuterP_{i-1}
+//   InnerL_i: Elliptic arc length between InnerP_i - InnerP_{i-1}
+//   W_i = |OuterP_i - InnerP_i|
+//   1.0 < dashLength < 3.0
+//
+//                                         OuterP_1          OuterP_0
+//                                         _+__-----------+ OuterCurve
+//                          OuterP_2 __---- |   OuterL_1  |
+//                             __+---       |             |
+//                        __---  | OuterL_2 |             |
+//            OuterP_3 _--       |           | W_1        | W_0
+//                   _+           |          |            |
+//                  /  \       W_2 |         |            |
+//                 /    \          |          | InnerL_1  |
+//                |      \          | InnerL_2|____-------+ InnerCurve
+//                |       \          |____----+          InnerP_0
+//               |     .   \    __---+       InnerP_1
+//               |          \ /     InnerP_2
+//              |     .     /+ InnerP_3
+//              |          |
+//              |    .    |
+//              |         |
+//              |        |
+//              |        |
+// OuterP_{n-1} +--------+ InnerP_{n-1}
+//              |        |
+//              |        |
+//              |        |
+//              |        |
+//              |        |
+//     OuterP_n +--------+ InnerP_n
+//
+// Returns region with [OuterCurve((OuterT_{2j} + OuterT_{2j-1}) / 2),
+//                      OuterCurve((OuterT_{2j} + OuterT_{2j-1}) / 2),
+//                      InnerCurve((OuterT_{2j} + OuterT_{2j+1}) / 2),
+//                      InnerCurve((OuterT_{2j} + OuterT_{2j+1}) / 2)],
+// to start and end with half segment.
+//
+//                                     _+__----+------+ OuterCurve
+//                               _+---- |      |######|
+//                         __+---#|     |      |######|
+//                    _+---##|####|     |      |######|
+//                 _-- |#####|#####|     |      |#####|
+//               _+     |#####|#####|    |      |#####|
+//              /  \     |#####|####|    |      |#####|
+//             /    \     |####|#####|    |     |#####|
+//            |      \     |####|####|    |____-+-----+ InnerCurve
+//            |       \     |####|____+---+
+//           |     .   \   __+---+
+//           |          \ /
+//          |     .     /+
+//          |          |
+//          |    .    |
+//          |         |
+//          |        |
+//          |        |
+//          +--------+
+//          |        |
+//          |        |
+//          +--------+
+//          |########|
+//          |########|
+//          +--------+
+
+class DashedCornerFinder {
+  typedef mozilla::gfx::Bezier Bezier;
+  typedef mozilla::gfx::Float Float;
+  typedef mozilla::gfx::Point Point;
+  typedef mozilla::gfx::Size Size;
+
+ public:
+  struct Result {
+    // Control points for the outer curve and the inner curve.
+    //
+    //   outerSectionBezier
+    //        |
+    //        v     _+ 3
+    //        ___---#|
+    //  0 +---#######|
+    //    |###########|
+    //     |###########|
+    //      |##########|
+    //       |##########|
+    //        |#########|
+    //         |#####____+ 3
+    //        0 +----
+    //              ^
+    //              |
+    //   innerSectionBezier
+    Bezier outerSectionBezier;
+    Bezier innerSectionBezier;
+
+    Result(const Bezier& aOuterSectionBezier, const Bezier& aInnerSectionBezier)
+        : outerSectionBezier(aOuterSectionBezier),
+          innerSectionBezier(aInnerSectionBezier) {}
+  };
+
+  //                       aCornerDim.width
+  //                     |<----------------->|
+  //                     |                   |
+  //                   --+-------------___---+--
+  //                   ^ |         __--      | ^
+  //                   | |       _-          | |
+  //                   | |     /             | | aBorderWidthH
+  //                   | |   /               | |
+  //                   | |  |                | v
+  //                   | | |             __--+--
+  // aCornerDim.height | ||            _-
+  //                   | ||           /
+  //                   | |           /
+  //                   | |          |
+  //                   | |          |
+  //                   | |         |
+  //                   | |         |
+  //                   v |         |
+  //                   --+---------+
+  //                     |         |
+  //                     |<------->|
+  //                     aBorderWidthV
+  DashedCornerFinder(const Bezier& aOuterBezier, const Bezier& aInnerBezier,
+                     Float aBorderWidthH, Float aBorderWidthV,
+                     const Size& aCornerDim);
+
+  bool HasMore(void) const;
+  Result Next(void);
+
+ private:
+  static const size_t MAX_LOOP = 32;
+
+  // Bezier control points for the outer curve and the inner curve.
+  //
+  //               ___---+ outer curve
+  //           __--      |
+  //         _-          |
+  //       /             |
+  //     /               |
+  //    |                |
+  //   |             __--+ inner curve
+  //  |            _-
+  //  |           /
+  // |           /
+  // |          |
+  // |          |
+  // |         |
+  // |         |
+  // |         |
+  // +---------+
+  Bezier mOuterBezier;
+  Bezier mInnerBezier;
+
+  Point mLastOuterP;
+  Point mLastInnerP;
+  Float mLastOuterT;
+  Float mLastInnerT;
+
+  // Length for each segment, ratio of the border width at that point.
+  Float mBestDashLength;
+
+  // If one of border-widths is 0, do not calculate mBestDashLength, and draw
+  // segments until it reaches the other side or exceeds mMaxCount.
+  bool mHasZeroBorderWidth;
+  bool mHasMore;
+
+  // The maximum number of segments.
+  size_t mMaxCount;
+
+  enum {
+    //                      radius.width
+    //                 |<----------------->|
+    //                 |                   |
+    //               --+-------------___---+--
+    //               ^ |         __--      | ^
+    //               | |       _-          | |
+    //               | |     /             + | top-width
+    //               | |   /               | |
+    //               | |  |                | v
+    //               | | |             __--+--
+    // radius.height | ||            _-
+    //               | ||           /
+    //               | |           /
+    //               | |          |
+    //               | |          |
+    //               | |         |
+    //               | |         |
+    //               v |         |
+    //               --+----+----+
+    //                 |         |
+    //                 |<------->|
+    //                  left-width
+
+    // * top-width == left-width
+    // * radius.width == radius.height
+    // * top-width < radius.width * 2
+    //
+    // Split the perfect circle's arc into 2n segments, each segment's length is
+    // top-width * dashLength. Then split the inner curve and the outer curve
+    // with same angles.
+    //
+    //                        radius.width
+    //                 |<---------------------->|
+    //                 |                        | v
+    //               --+------------------------+--
+    //               ^ |                        | | top-width / 2
+    //               | | perfect                | |
+    //               | | circle's         ___---+--
+    //               | | arc          __-+      | ^
+    //               | |  |         _-   |      |
+    // radius.height | |  |       +       |     +--
+    //               | |  |     /  \      |     |
+    //               | |  |    |     \     |    |
+    //               | |  |   |       \     |   |
+    //               | |  +->|          \   |   |
+    //               | |    +---__       \   |  |
+    //               | |    |     --__     \  | |
+    //               | |    |         ---__ \ | |
+    //               v |    |              --_\||
+    //               --+----+----+--------------+
+    //                 |    |    |
+    //                 |<-->|    |
+    //               left-width / 2
+    PERFECT,
+
+    // Other cases.
+    //
+    // Split the outer curve and the inner curve into 2n segments, each segment
+    // satisfies following:
+    //   (OuterL_i + InnerL_i) / 2 == dashLength * (W_i + W_{i-1}) / 2
+    OTHER
+  } mType;
+
+  size_t mI;
+  size_t mCount;
+
+  // Determine mType from parameters.
+  void DetermineType(Float aBorderWidthH, Float aBorderWidthV);
+
+  // Reset calculation.
+  void Reset(void);
+
+  // Find next segment.
+  Float FindNext(Float dashLength);
+
+  // Find mBestDashLength for parameters.
+  void FindBestDashLength(Float aMinBorderWidth, Float aMaxBorderWidth,
+                          Float aMinBorderRadius, Float aMaxBorderRadius);
+
+  // Fill corner with dashes with given dash length, and return the number of
+  // segments and last segment's dash length.
+  bool GetCountAndLastDashLength(Float aDashLength, size_t* aCount,
+                                 Float* aActualDashLength);
+};
+
+}  // namespace mozilla
+
+#endif /* mozilla_DashedCornerFinder_h_ */