live pipe connection overhaul clean up.

Author: jchanvfx

NodeGraphQt/qgraphics/pipe.py

@@ -6,7 +6,8 @@
     PIPE_DEFAULT_COLOR, PIPE_ACTIVE_COLOR,
     PIPE_HIGHLIGHT_COLOR, PIPE_DISABLED_COLOR,
     PIPE_STYLE_DASHED, PIPE_STYLE_DEFAULT, PIPE_STYLE_DOTTED,
-    PIPE_LAYOUT_STRAIGHT, PIPE_WIDTH, IN_PORT, OUT_PORT, Z_VAL_PIPE
+    PIPE_LAYOUT_STRAIGHT, PIPE_WIDTH, IN_PORT, OUT_PORT, Z_VAL_PIPE,
+    Z_VAL_NODE_WIDGET
 )
 from NodeGraphQt.qgraphics.port import PortItem
 
@@ -130,7 +131,7 @@ def paint(self, painter, option, widget):
 
         painter.restore()  # QPaintDevice: Cannot destroy paint device that is being painted
 
-    def draw_path(self, start_port, end_port, cursor_pos=None):
+    def draw_path(self, start_port, end_port=None, cursor_pos=None):
         """
         Draws the path between ports.
 
@@ -182,6 +183,10 @@ def draw_path(self, start_port, end_port, cursor_pos=None):
         path.cubicTo(ctr_point1, ctr_point2, pos2)
         self.setPath(path)
 
+    def reset_path(self):
+        path = QtGui.QPainterPath(QtCore.QPointF(0.0, 0.0))
+        self.setPath(path)
+
     def calc_distance(self, p1, p2):
         x = math.pow((p2.x() - p1.x()), 2)
         y = math.pow((p2.y() - p1.y()), 2)
@@ -293,3 +298,12 @@ def delete(self):
         # TODO: not sure if we need this...?
         del self
 
+
+class LivePipe(Pipe):
+
+    def __init__(self, input_port=None, output_port=None):
+        super(LivePipe, self).__init__(input_port, output_port)
+        self.setZValue(Z_VAL_NODE_WIDGET + 1)
+        self.activate()
+        self.style = PIPE_STYLE_DASHED
+        self.shift_selected = False

NodeGraphQt/widgets/viewer.py

@@ -5,12 +5,10 @@
 from NodeGraphQt import QtGui, QtCore, QtWidgets
 from NodeGraphQt.constants import (IN_PORT, OUT_PORT,
                                    PIPE_LAYOUT_CURVED,
-                                   PIPE_STYLE_DASHED,
-                                   SCENE_AREA,
-                                   Z_VAL_NODE_WIDGET)
+                                   SCENE_AREA,)
 from NodeGraphQt.qgraphics.node_abstract import AbstractNodeItem
 from NodeGraphQt.qgraphics.node_backdrop import BackdropNodeItem
-from NodeGraphQt.qgraphics.pipe import Pipe
+from NodeGraphQt.qgraphics.pipe import Pipe, LivePipe
 from NodeGraphQt.qgraphics.port import PortItem
 from NodeGraphQt.qgraphics.slicer import SlicerPipe
 from NodeGraphQt.widgets.scene import NodeScene
@@ -55,7 +53,6 @@ def __init__(self, parent=None):
         self.resize(1000, 800)
 
         self._pipe_layout = PIPE_LAYOUT_CURVED
-        self._live_pipe = None
         self._detached_port = None
         self._start_port = None
         self._origin_pos = None
@@ -65,6 +62,11 @@ def __init__(self, parent=None):
         self._rubber_band = QtWidgets.QRubberBand(
             QtWidgets.QRubberBand.Rectangle, self
         )
+
+        self._live_pipe = LivePipe()
+        self._live_pipe.setVisible(False)
+        self.scene().addItem(self._live_pipe)
+
         self._pipe_slicer = SlicerPipe()
         self._pipe_slicer.setVisible(False)
         self.scene().addItem(self._pipe_slicer)
@@ -87,6 +89,9 @@ def __init__(self, parent=None):
         self.LMB_state = False
         self.RMB_state = False
         self.MMB_state = False
+        self.ALT_state = False
+        self.CTRL_state = False
+        self.SHIFT_state = False
 
     def __repr__(self):
         return '{}.{}()'.format(
@@ -123,7 +128,10 @@ def _items_near(self, pos, item_type=None, width=20, height=20):
         x, y = pos.x() - width, pos.y() - height
         rect = QtCore.QRectF(x, y, width, height)
         items = []
+        excl = [self._live_pipe, self._pipe_slicer]
         for item in self.scene().items(rect):
+            if item in excl:
+                continue
             if not item_type or isinstance(item, item_type):
                 items.append(item)
         return items
@@ -135,7 +143,8 @@ def _on_search_submitted(self, node_type):
     def _on_pipes_sliced(self, path):
         self.connection_sliced.emit([
             [i.input_port, i.output_port]
-            for i in self.scene().items(path) if isinstance(i, Pipe)
+            for i in self.scene().items(path)
+            if isinstance(i, Pipe) and i != self._live_pipe
         ])
 
     # --- reimplemented events ---
@@ -151,15 +160,13 @@ def contextMenuEvent(self, event):
             return super(NodeViewer, self).contextMenuEvent(event)
 
     def mousePressEvent(self, event):
-        alt_modifier = event.modifiers() == QtCore.Qt.AltModifier
-        shift_modifier = event.modifiers() == QtCore.Qt.ShiftModifier
-
         if event.button() == QtCore.Qt.LeftButton:
             self.LMB_state = True
         elif event.button() == QtCore.Qt.RightButton:
             self.RMB_state = True
         elif event.button() == QtCore.Qt.MiddleButton:
             self.MMB_state = True
+
         self._origin_pos = event.pos()
         self._previous_pos = event.pos()
         self._prev_selection = self.selected_nodes()
@@ -172,19 +179,21 @@ def mousePressEvent(self, event):
         map_pos = self.mapToScene(event.pos())
 
         # pipe slicer enabled.
-        if event.modifiers() == (QtCore.Qt.AltModifier | QtCore.Qt.ShiftModifier):
+        if self.ALT_state and self.SHIFT_state:
             self._pipe_slicer.draw_path(map_pos, map_pos)
             self._pipe_slicer.setVisible(True)
             return
 
-        if alt_modifier:
+        # pan mode.
+        if self.ALT_state:
             return
 
         items = self._items_near(map_pos, None, 20, 20)
         nodes = [i for i in items if isinstance(i, AbstractNodeItem)]
+        pipes = [i for i in items if isinstance(i, Pipe)]
 
         # toggle extend node selection.
-        if shift_modifier:
+        if self.SHIFT_state:
             for node in nodes:
                 node.selected = not node.selected
 
@@ -193,7 +202,7 @@ def mousePressEvent(self, event):
             {n: n.xy_pos for n in self.selected_nodes()}
         )
 
-        # show selection selection marquee
+        # show selection selection marquee.
         if self.LMB_state and not items:
             rect = QtCore.QRect(self._previous_pos, QtCore.QSize())
             rect = rect.normalized()
@@ -202,7 +211,8 @@ def mousePressEvent(self, event):
             self._rubber_band.setGeometry(rect)
             self._rubber_band.show()
 
-        if not shift_modifier:
+        # allow new live pipe with the shift modifier.
+        if not self.SHIFT_state or self.SHIFT_state and pipes:
             super(NodeViewer, self).mousePressEvent(event)
 
     def mouseReleaseEvent(self, event):
@@ -241,22 +251,21 @@ def mouseReleaseEvent(self, event):
         super(NodeViewer, self).mouseReleaseEvent(event)
 
     def mouseMoveEvent(self, event):
-        alt_modifier = event.modifiers() == QtCore.Qt.AltModifier
-        shift_modifier = event.modifiers() == QtCore.Qt.ShiftModifier
-        if event.modifiers() == (QtCore.Qt.AltModifier | QtCore.Qt.ShiftModifier):
-            if self.LMB_state:
+        if self.ALT_state and self.SHIFT_state:
+            if self.LMB_state and self._pipe_slicer.isVisible():
                 p1 = self._pipe_slicer.path().pointAtPercent(0)
                 p2 = self.mapToScene(self._previous_pos)
                 self._pipe_slicer.draw_path(p1, p2)
-                self._previous_pos = event.pos()
-                super(NodeViewer, self).mouseMoveEvent(event)
-                return
+                self._pipe_slicer.show()
+            self._previous_pos = event.pos()
+            super(NodeViewer, self).mouseMoveEvent(event)
+            return
 
-        if self.MMB_state and alt_modifier:
+        if self.MMB_state and self.ALT_state:
             pos_x = (event.x() - self._previous_pos.x())
             zoom = 0.1 if pos_x > 0 else -0.1
             self._set_viewer_zoom(zoom, 0.05)
-        elif self.MMB_state or (self.LMB_state and alt_modifier):
+        elif self.MMB_state or (self.LMB_state and self.ALT_state):
             pos_x = (event.x() - self._previous_pos.x())
             pos_y = (event.y() - self._previous_pos.y())
             self._set_viewer_pan(pos_x, pos_y)
@@ -270,7 +279,7 @@ def mouseMoveEvent(self, event):
             self.scene().setSelectionArea(path, QtCore.Qt.IntersectsItemShape)
             self.scene().update(map_rect)
 
-            if shift_modifier and self._prev_selection:
+            if self.SHIFT_state and self._prev_selection:
                 for node in self._prev_selection:
                     if node not in self.selected_nodes():
                         node.selected = True
@@ -309,6 +318,24 @@ def dragMoveEvent(self, event):
     def dragLeaveEvent(self, event):
         event.ignore()
 
+    def keyPressEvent(self, event):
+        self.ALT_state = event.modifiers() == QtCore.Qt.AltModifier
+        self.CTRL_state = event.modifiers() == QtCore.Qt.ControlModifier
+        self.SHIFT_state = event.modifiers() == QtCore.Qt.ShiftModifier
+
+        # Todo: find a better solution to catch modifier keys.
+        if event.modifiers() == (QtCore.Qt.AltModifier | QtCore.Qt.ShiftModifier):
+            self.ALT_state = True
+            self.SHIFT_state = True
+
+        super(NodeViewer, self).keyPressEvent(event)
+
+    def keyReleaseEvent(self, event):
+        self.ALT_state = event.modifiers() == QtCore.Qt.AltModifier
+        self.CTRL_state = event.modifiers() == QtCore.Qt.ControlModifier
+        self.SHIFT_state = event.modifiers() == QtCore.Qt.ShiftModifier
+        super(NodeViewer, self).keyReleaseEvent(event)
+
     # --- scene events ---
 
     def sceneMouseMoveEvent(self, event):
@@ -320,7 +347,7 @@ def sceneMouseMoveEvent(self, event):
             event (QtWidgets.QGraphicsSceneMouseEvent):
                 The event handler from the QtWidgets.QGraphicsScene
         """
-        if not self._live_pipe:
+        if not self._live_pipe.isVisible():
             return
         if not self._start_port:
             return
@@ -334,7 +361,7 @@ def sceneMouseMoveEvent(self, event):
             pos.setX(pos.x() + x)
             pos.setY(pos.y() + y)
 
-        self._live_pipe.draw_path(self._start_port, None, pos)
+        self._live_pipe.draw_path(self._start_port, cursor_pos=pos)
 
     def sceneMousePressEvent(self, event):
         """
@@ -347,10 +374,10 @@ def sceneMousePressEvent(self, event):
                 The event handler from the QtWidgets.QGraphicsScene
         """
         # pipe slicer enabled.
-        if event.modifiers() == (QtCore.Qt.AltModifier | QtCore.Qt.ShiftModifier):
+        if self.ALT_state and self.SHIFT_state:
             return
         # viewer pan mode.
-        if event.modifiers() == QtCore.Qt.AltModifier:
+        if self.ALT_state:
             return
 
         pos = event.scenePos()
@@ -384,13 +411,18 @@ def sceneMousePressEvent(self, event):
             if not self.LMB_state:
                 return
             pipe = pipe_items[0]
-            attr = {IN_PORT: 'output_port', OUT_PORT: 'input_port'}
             from_port = pipe.port_from_pos(pos, True)
             from_port._hovered = True
 
+            attr = {IN_PORT: 'output_port', OUT_PORT: 'input_port'}
             self._detached_port = getattr(pipe, attr[from_port.port_type])
             self.start_live_connection(from_port)
-            self._live_pipe.draw_path(self._start_port, None, pos)
+            self._live_pipe.draw_path(self._start_port, cursor_pos=pos)
+
+            if self.SHIFT_state:
+                self._live_pipe.shift_selected = True
+                return
+
             pipe.delete()
 
     def sceneMouseReleaseEvent(self, event):
@@ -402,7 +434,7 @@ def sceneMouseReleaseEvent(self, event):
             event (QtWidgets.QGraphicsSceneMouseEvent):
                 The event handler from the QtWidgets.QGraphicsScene
         """
-        if not self._live_pipe:
+        if not self._live_pipe.isVisible():
             return
 
         self._start_port._hovered = False
@@ -419,7 +451,7 @@ def sceneMouseReleaseEvent(self, event):
 
         # if port disconnected from existing pipe.
         if end_port is None:
-            if self._detached_port:
+            if self._detached_port and not self._live_pipe.shift_selected:
                 disconnected.append((self._start_port, self._detached_port))
                 self.connection_changed.emit(disconnected, connected)
 
@@ -477,29 +509,25 @@ def sceneMouseReleaseEvent(self, event):
     def start_live_connection(self, selected_port):
         """
         create new pipe for the connection.
-        (draws the live pipe from the port following the cursor position)
+        (show the live pipe visibility from the port following the cursor position)
         """
         if not selected_port:
             return
         self._start_port = selected_port
-        self._live_pipe = Pipe()
-        self._live_pipe.setZValue(Z_VAL_NODE_WIDGET)
-        self._live_pipe.activate()
-        self._live_pipe.style = PIPE_STYLE_DASHED
         if self._start_port.type == IN_PORT:
             self._live_pipe.input_port = self._start_port
         elif self._start_port == OUT_PORT:
             self._live_pipe.output_port = self._start_port
-        self.scene().addItem(self._live_pipe)
+        self._live_pipe.setVisible(True)
 
     def end_live_connection(self):
         """
         delete live connection pipe and reset start port.
-        (removes the pipe item used for drawing the live connection)
+        (hides the pipe item used for drawing the live connection)
         """
-        if self._live_pipe:
-            self._live_pipe.delete()
-            self._live_pipe = None
+        self._live_pipe.reset_path()
+        self._live_pipe.setVisible(False)
+        self._live_pipe.shift_selected = False
         self._start_port = None
 
     def establish_connection(self, start_port, end_port):
@@ -596,8 +624,9 @@ def save_dialog(self, current_dir=None, ext=None):
 
     def all_pipes(self):
         pipes = []
+        excl = [self._live_pipe, self._pipe_slicer]
         for item in self.scene().items():
-            if isinstance(item, Pipe):
+            if isinstance(item, Pipe) and item not in excl:
                 pipes.append(item)
         return pipes