Merge remote-tracking branch 'upstream/3.4' into merge-3.4

modules/imgproc/src/drawing.cpp

@@ -63,7 +63,7 @@ CollectPolyEdges( Mat& img, const Point2l* v, int npts,
                   int shift, Point offset=Point() );
 
 static void
-FillEdgeCollection( Mat& img, std::vector<PolyEdge>& edges, const void* color );
+FillEdgeCollection( Mat& img, std::vector<PolyEdge>& edges, const void* color, int line_type);
 
 static void
 PolyLine( Mat& img, const Point2l* v, int npts, bool closed,
@@ -1049,7 +1049,7 @@ EllipseEx( Mat& img, Point2l center, Size2l axes,
         v.push_back(center);
         std::vector<PolyEdge> edges;
         CollectPolyEdges( img,  &v[0], (int)v.size(), edges, color, line_type, XY_SHIFT );
-        FillEdgeCollection( img, edges, color );
+        FillEdgeCollection( img, edges, color, line_type );
     }
 }
 
@@ -1277,37 +1277,60 @@ CollectPolyEdges( Mat& img, const Point2l* v, int count, std::vector<PolyEdge>&
         pt1.x = (pt1.x + offset.x) << (XY_SHIFT - shift);
         pt1.y = (pt1.y + delta) >> shift;
 
-        if( line_type < cv::LINE_AA )
+        Point2l pt0c(pt0), pt1c(pt1);
+
+        if (line_type < cv::LINE_AA)
         {
             t0.y = pt0.y; t1.y = pt1.y;
             t0.x = (pt0.x + (XY_ONE >> 1)) >> XY_SHIFT;
             t1.x = (pt1.x + (XY_ONE >> 1)) >> XY_SHIFT;
-            Line( img, t0, t1, color, line_type );
+            Line(img, t0, t1, color, line_type);
+
+            // use clipped endpoints to create a more accurate PolyEdge
+            if ((unsigned)t0.x >= (unsigned)(img.cols) ||
+                (unsigned)t1.x >= (unsigned)(img.cols) ||
+                (unsigned)t0.y >= (unsigned)(img.rows) ||
+                (unsigned)t1.y >= (unsigned)(img.rows))
+            {
+                clipLine(img.size(), t0, t1);
+
+                if (t0.y != t1.y)
+                {
+                    pt0c.y = t0.y; pt1c.y = t1.y;
+                    pt0c.x = (int64)(t0.x) << XY_SHIFT;
+                    pt1c.x = (int64)(t1.x) << XY_SHIFT;
+                }
+            }
+            else
+            {
+                pt0c.x += XY_ONE >> 1;
+                pt1c.x += XY_ONE >> 1;
+            }
         }
         else
         {
             t0.x = pt0.x; t1.x = pt1.x;
             t0.y = pt0.y << XY_SHIFT;
             t1.y = pt1.y << XY_SHIFT;
-            LineAA( img, t0, t1, color );
+            LineAA(img, t0, t1, color);
         }
 
-        if( pt0.y == pt1.y )
+        if (pt0.y == pt1.y)
             continue;
 
-        if( pt0.y < pt1.y )
+        edge.dx = (pt1c.x - pt0c.x) / (pt1c.y - pt0c.y);
+        if (pt0.y < pt1.y)
         {
             edge.y0 = (int)(pt0.y);
             edge.y1 = (int)(pt1.y);
-            edge.x = pt0.x;
+            edge.x = pt0c.x + (pt0.y - pt0c.y) * edge.dx; // correct starting point for clipped lines
         }
         else
         {
             edge.y0 = (int)(pt1.y);
             edge.y1 = (int)(pt0.y);
-            edge.x = pt1.x;
+            edge.x = pt1c.x + (pt1.y - pt1c.y) * edge.dx; // correct starting point for clipped lines
         }
-        edge.dx = (pt1.x - pt0.x) / (pt1.y - pt0.y);
         edges.push_back(edge);
     }
 }
@@ -1324,7 +1347,7 @@ struct CmpEdges
 /**************** helper macros and functions for sequence/contour processing ***********/
 
 static void
-FillEdgeCollection( Mat& img, std::vector<PolyEdge>& edges, const void* color )
+FillEdgeCollection( Mat& img, std::vector<PolyEdge>& edges, const void* color, int line_type)
 {
     PolyEdge tmp;
     int i, y, total = (int)edges.size();
@@ -1333,6 +1356,12 @@ FillEdgeCollection( Mat& img, std::vector<PolyEdge>& edges, const void* color )
     int y_max = INT_MIN, y_min = INT_MAX;
     int64 x_max = 0xFFFFFFFFFFFFFFFF, x_min = 0x7FFFFFFFFFFFFFFF;
     int pix_size = (int)img.elemSize();
+    int delta;
+
+    if (line_type < CV_AA)
+        delta = 0;
+    else
+        delta = XY_ONE - 1;
 
     if( total < 2 )
         return;
@@ -1411,12 +1440,12 @@ FillEdgeCollection( Mat& img, std::vector<PolyEdge>& edges, const void* color )
 
                     if (keep_prelast->x > prelast->x)
                     {
-                        x1 = (int)((prelast->x + XY_ONE - 1) >> XY_SHIFT);
+                        x1 = (int)((prelast->x + delta) >> XY_SHIFT);
                         x2 = (int)(keep_prelast->x >> XY_SHIFT);
                     }
                     else
                     {
-                        x1 = (int)((keep_prelast->x + XY_ONE - 1) >> XY_SHIFT);
+                        x1 = (int)((keep_prelast->x + delta) >> XY_SHIFT);
                         x2 = (int)(prelast->x >> XY_SHIFT);
                     }
 
@@ -2017,7 +2046,7 @@ void fillPoly( InputOutputArray _img, const Point** pts, const int* npts, int nc
         CollectPolyEdges(img, _pts.data(), npts[i], edges, buf, line_type, shift, offset);
     }
 
-    FillEdgeCollection(img, edges, buf);
+    FillEdgeCollection(img, edges, buf, line_type);
 }
 
 void polylines( InputOutputArray _img, const Point* const* pts, const int* npts, int ncontours, bool isClosed,
@@ -2672,7 +2701,7 @@ cvDrawContours( void* _img, CvSeq* contour,
     }
 
     if( thickness < 0 )
-        cv::FillEdgeCollection( img, edges, ext_buf );
+        cv::FillEdgeCollection( img, edges, ext_buf, line_type);
 
     if( h_next && contour0 )
         contour0->h_next = h_next;