Merge pull request slaclab#1072 from nstelter-slac/arrow_size_option

ENH: Add option to change size of arrows on drawn lines

pydm/tests/widgets/test_drawing.py

@@ -1230,21 +1230,42 @@ def test_pydmdrawingpolyline_arrows(qapp, qtbot, points, num_points):
     num_points :int
         The actual number of vertices of the polygon.
     """
-    drawing = PyDMDrawingPolyline()
-    qtbot.addWidget(drawing)
+    # try with polyline
+    polyLine = PyDMDrawingPolyline()
+    qtbot.addWidget(polyLine)
 
     # make sure points seutp correctly before drawing arrows
-    drawing.setPoints(points)
-    assert len(drawing.getPoints()) == num_points
+    polyLine.setPoints(points)
+    assert len(polyLine.getPoints()) == num_points
 
     # enable all arrow options
-    drawing._arrow_end_point_selection = True
-    drawing._arrow_start_point_selection = True
-    drawing._arrow_mid_point_selection = True
-    drawing._arrow_mid_point_flipped = True
-    drawing.draw_item(drawing._painter)
+    polyLine._arrow_end_point_selection = True
+    polyLine._arrow_start_point_selection = True
+    polyLine._arrow_mid_point_selection = True
+    polyLine._arrow_mid_point_flipped = True
+    polyLine.draw_item(polyLine._painter)
+    polyLine.show()
+
+    # just be sure size prop exists and can be changed without breaking things
+    polyLine._arrow_size += 3
+    polyLine.draw_item(polyLine._painter)
+    polyLine.show()
+
+    # now try with line
+    line = PyDMDrawingLine()
+    qtbot.addWidget(line)
 
-    drawing.show()
+    # enable all arrow options
+    line._arrow_end_point_selection = True
+    line._arrow_start_point_selection = True
+    line._arrow_mid_point_selection = True
+    line._arrow_mid_point_flipped = True
+    line.draw_item(polyLine._painter)
+    line.show()
+
+    line._arrow_size += 3
+    line.draw_item(polyLine._painter)
+    line.show()
 
 
 # # ---------------------------

pydm/widgets/drawing.py

@@ -473,6 +473,7 @@ def __init__(self, parent=None, init_channel=None):
         self._arrow_start_point_selection = False
         self._arrow_mid_point_selection = False
         self._mid_point_arrow_flipped = False
+        self._arrow_size = 6  # 6 is arbitrary size that looked good for default, not in any specific 'units'
         self.rotation = 0
         self.penStyle = Qt.SolidLine
         self.penWidth = 1
@@ -554,20 +555,44 @@ def draw_item(self, painter):
 
         # Draw the arrows
         if self._arrow_end_point_selection:
-            points = self._arrow_points(start_point, end_point, 6, 6)
+            points = self._arrow_points(start_point, end_point, self._arrow_size, self._arrow_size)
             painter.drawPolygon(points)
 
         if self._arrow_start_point_selection:
-            points = self._arrow_points(end_point, start_point, 6, 6)
+            points = self._arrow_points(end_point, start_point, self._arrow_size, self._arrow_size)
             painter.drawPolygon(points)
 
         if self._arrow_mid_point_selection:
             if self._mid_point_arrow_flipped:
-                points = self._arrow_points(start_point, mid_point, 6, 6)
+                points = self._arrow_points(start_point, mid_point, self._arrow_size, self._arrow_size)
             else:
-                points = self._arrow_points(end_point, mid_point, 6, 6)
+                points = self._arrow_points(end_point, mid_point, self._arrow_size, self._arrow_size)
             painter.drawPolygon(points)
 
+    @Property(int)
+    def arrowSize(self):
+        """
+        Size to render line arrows.
+
+        Returns
+        -------
+        bool
+        """
+        return self._arrow_size
+
+    @arrowSize.setter
+    def arrowSize(self, new_size):
+        """
+        Size to render line arrows.
+
+        Parameters
+        -------
+        new_selection : bool
+        """
+        if self._arrow_size != new_size:
+            self._arrow_size = new_size
+            self.update()
+
     @Property(bool)
     def arrowEndPoint(self):
         """
@@ -1205,6 +1230,7 @@ def __init__(self, parent=None, init_channel=None):
         self._arrow_start_point_selection = False
         self._arrow_mid_point_selection = False
         self._arrow_mid_point_flipped = False
+        self._arrow_size = 6  # 6 is arbitrary size that looked good for default, not in any specific 'units'
         self.penStyle = Qt.SolidLine
         self.penWidth = 1
         self._points = []
@@ -1242,20 +1268,22 @@ def p2d(pt):
                     midpoint_x = (point1.x() + point2.x()) / 2
                     midpoint_y = (point1.y() + point2.y()) / 2
                     midpoint = QPointF(midpoint_x, midpoint_y)
-                    points = PyDMDrawingLine._arrow_points(point1, midpoint, 6, 6)  # 6 = arbitrary arrow size
+                    points = PyDMDrawingLine._arrow_points(point1, midpoint, self._arrow_size, self._arrow_size)
                     painter.drawPolygon(points)
 
         # Draw the arrows
         if self._arrow_end_point_selection and (len(self._points[1]) >= 2):
-            points = PyDMDrawingLine._arrow_points(p2d(self._points[1]), p2d(self._points[0]), 6, 6)
+            points = PyDMDrawingLine._arrow_points(
+                p2d(self._points[1]), p2d(self._points[0]), self._arrow_size, self._arrow_size
+            )
             painter.drawPolygon(points)
 
         if self._arrow_start_point_selection and (len(self._points[1]) >= 2):
             points = PyDMDrawingLine._arrow_points(
                 p2d(self._points[len(self._points) - 2]),
                 p2d(self._points[len(self._points) - 1]),
-                6,
-                6,
+                self._arrow_size,
+                self._arrow_size,
             )
             painter.drawPolygon(points)
 
@@ -1340,6 +1368,30 @@ def resetPoints(self):
         self._points = []
         self.update()
 
+    @Property(int)
+    def arrowSize(self):
+        """
+        Size to render line arrows.
+
+        Returns
+        -------
+        bool
+        """
+        return self._arrow_size
+
+    @arrowSize.setter
+    def arrowSize(self, new_size):
+        """
+        Size to render line arrows.
+
+        Parameters
+        -------
+        new_selection : bool
+        """
+        if self._arrow_size != new_size:
+            self._arrow_size = new_size
+            self.update()
+
     @Property(bool)
     def arrowEndPoint(self):
         """