From 2fd830c940efd9c0217b3a1d3637e1f8212f46fc Mon Sep 17 00:00:00 2001
From: Hermet Park <chuneon.park@samsung.com>
Date: Thu, 1 Jul 2021 20:04:30 +0900
Subject: [PATCH] common shape: allow to reset stroke dash.

user may need to reset stroke dash to off,
now stroke api allows it.
---
 inc/thorvg.h           |  5 +++--
 src/lib/tvgShape.cpp   |  4 +++-
 src/lib/tvgShapeImpl.h | 32 ++++++++++++++++++--------------
 3 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/inc/thorvg.h b/inc/thorvg.h
index 26df36d0..67833a0d 100644
--- a/inc/thorvg.h
+++ b/inc/thorvg.h
@@ -799,10 +799,11 @@ public:
      *
      * @retval Result::Success When succeed.
      * @retval Result::FailedAllocation An internal error with a memory allocation for an object to be dashed.
-     * @retval Result::InvalidArguments In case a @c nullptr is passed as the @p dashPattern,
-     *         the given length of the array is less than two or any of the @p dashPattern values is zero or less.
+     * @retval Result::InvalidArguments In case that either @p dashPattern is @c nullptr or @p cnt is zero.
      *
      * @note If any of the dash pattern values is zero, this function has no effect.
+     * @note To reset the stroke dash pattern, pass @c nullptr to @p dashPattern and zero to @p cnt.
+     * @warning @p cnt must be greater than 1 if the dash pattern is valid.
      */
     Result stroke(const float* dashPattern, uint32_t cnt) noexcept;
 
diff --git a/src/lib/tvgShape.cpp b/src/lib/tvgShape.cpp
index 0af9ca1c..3e671953 100644
--- a/src/lib/tvgShape.cpp
+++ b/src/lib/tvgShape.cpp
@@ -358,7 +358,9 @@ const Fill* Shape::strokeFill() const noexcept
 
 Result Shape::stroke(const float* dashPattern, uint32_t cnt) noexcept
 {
-    if (cnt < 2 || !dashPattern) return Result::InvalidArguments;
+    if ((cnt == 1) || (!dashPattern && cnt > 0) || (dashPattern && cnt == 0)) {
+        return Result::InvalidArguments;
+    }
 
     for (uint32_t i = 0; i < cnt; i++)
         if (dashPattern[i] < FLT_EPSILON) return Result::InvalidArguments;
diff --git a/src/lib/tvgShapeImpl.h b/src/lib/tvgShapeImpl.h
index b978221a..53e9931f 100644
--- a/src/lib/tvgShapeImpl.h
+++ b/src/lib/tvgShapeImpl.h
@@ -330,22 +330,26 @@ struct Shape::Impl
 
     bool strokeDash(const float* pattern, uint32_t cnt)
     {
-       if (!stroke) stroke = new ShapeStroke();
-       if (!stroke) return false;
-
-        if (stroke->dashCnt != cnt) {
-            if (stroke->dashPattern) free(stroke->dashPattern);
+        //Reset dash
+        if (!pattern && cnt == 0) {
+            free(stroke->dashPattern);
             stroke->dashPattern = nullptr;
+        } else {
+            if (!stroke) stroke = new ShapeStroke();
+            if (!stroke) return false;
+
+            if (stroke->dashCnt != cnt) {
+                free(stroke->dashPattern);
+                stroke->dashPattern = nullptr;
+            }
+            if (!stroke->dashPattern) {
+                stroke->dashPattern = static_cast<float*>(malloc(sizeof(float) * cnt));
+                if (!stroke->dashPattern) return false;
+            }
+            for (uint32_t i = 0; i < cnt; ++i) {
+                stroke->dashPattern[i] = pattern[i];
+            }
         }
-
-        if (!stroke->dashPattern) {
-            stroke->dashPattern = static_cast<float*>(malloc(sizeof(float) * cnt));
-            if (!stroke->dashPattern) return false;
-        }
-
-        for (uint32_t i = 0; i < cnt; ++i)
-            stroke->dashPattern[i] = pattern[i];
-
         stroke->dashCnt = cnt;
         flag |= RenderUpdateFlag::Stroke;