pipe connection slicer tool

NodeGraphQt/base/graph.py

@@ -59,6 +59,7 @@ def __repr__(self):
     def _wire_signals(self):
         # internal signals.
         self._viewer.search_triggered.connect(self._on_search_triggered)
+        self._viewer.connection_sliced.connect(self._on_connection_sliced)
         self._viewer.connection_changed.connect(self._on_connection_changed)
         self._viewer.moved_nodes.connect(self._on_nodes_moved)
         self._viewer.node_double_clicked.connect(self._on_node_double_clicked)
@@ -188,6 +189,26 @@ def _on_connection_changed(self, disconnected, connected):
             port1.connect_to(port2)
         self._undo_stack.endMacro()
 
+    def _on_connection_sliced(self, ports):
+        """
+        slot when connection pipes have been sliced.
+
+        Args:
+            ports (list[list[widgets.port.PortItem]]):
+                pair list of port connections (in port, out port)
+        """
+        if not ports:
+            return
+        ptypes = {'in': 'inputs', 'out': 'outputs'}
+        self._undo_stack.beginMacro('slice connections')
+        for p1_view, p2_view in ports:
+            node1 = self._model.nodes[p1_view.node.id]
+            node2 = self._model.nodes[p2_view.node.id]
+            port1 = getattr(node1, ptypes[p1_view.port_type])()[p1_view.name]
+            port2 = getattr(node2, ptypes[p2_view.port_type])()[p2_view.name]
+            port1.disconnect_from(port2)
+        self._undo_stack.endMacro()
+
     @property
     def model(self):
         """

NodeGraphQt/constants.py

@@ -13,6 +13,7 @@
 PIPE_DISABLED_COLOR = (190, 20, 20, 255)
 PIPE_ACTIVE_COLOR = (70, 255, 220, 255)
 PIPE_HIGHLIGHT_COLOR = (232, 184, 13, 255)
+PIPE_SLICER_COLOR = (255, 50, 75)
 #: The draw the connection pipes as straight lines.
 PIPE_LAYOUT_STRAIGHT = 0
 #: The draw the connection pipes as curved lines.

NodeGraphQt/qgraphics/slicer.py

@@ -0,0 +1,63 @@
+#!/usr/bin/python
+from NodeGraphQt import QtCore, QtGui, QtWidgets
+from NodeGraphQt.constants import Z_VAL_NODE_WIDGET, PIPE_SLICER_COLOR
+
+
+class SlicerPipe(QtWidgets.QGraphicsPathItem):
+    """
+    Base item used for drawing the pipe connection slicer.
+    """
+
+    def __init__(self):
+        super(SlicerPipe, self).__init__()
+        self.setZValue(Z_VAL_NODE_WIDGET + 2)
+
+    def paint(self, painter, option, widget):
+        """
+        Draws the slicer pipe.
+
+        Args:
+            painter (QtGui.QPainter): painter used for drawing the item.
+            option (QtGui.QStyleOptionGraphicsItem):
+                used to describe the parameters needed to draw.
+            widget (QtWidgets.QWidget): not used.
+        """
+        color = QtGui.QColor(*PIPE_SLICER_COLOR)
+        p1 = self.path().pointAtPercent(0)
+        p2 = self.path().pointAtPercent(1)
+        size = 6.0
+        offset = size / 2
+
+        painter.save()
+        painter.setRenderHint(painter.Antialiasing, True)
+
+        font = painter.font()
+        font.setPointSize(12)
+        painter.setFont(font)
+        text = 'slice'
+        text_x = painter.fontMetrics().width(text) / 2
+        text_y = painter.fontMetrics().height() / 1.5
+        text_pos = QtCore.QPointF(p1.x() - text_x, p1.y() - text_y)
+        text_color = QtGui.QColor(*PIPE_SLICER_COLOR)
+        text_color.setAlpha(80)
+        painter.setPen(QtGui.QPen(text_color, 1.5, QtCore.Qt.SolidLine))
+        painter.drawText(text_pos, text)
+
+        painter.setPen(QtGui.QPen(color, 1.5, QtCore.Qt.DashLine))
+        painter.drawPath(self.path())
+
+        painter.setPen(QtGui.QPen(color, 1.5, QtCore.Qt.SolidLine))
+        painter.setBrush(color)
+
+        rect = QtCore.QRectF(p1.x() - offset, p1.y() - offset, size, size)
+        painter.drawEllipse(rect)
+
+        rect = QtCore.QRectF(p2.x() - offset, p2.y() - offset, size, size)
+        painter.drawEllipse(rect)
+        painter.restore()
+
+    def draw_path(self, p1, p2):
+        path = QtGui.QPainterPath()
+        path.moveTo(p1)
+        path.lineTo(p2)
+        self.setPath(path)

NodeGraphQt/widgets/viewer.py

@@ -12,6 +12,7 @@
 from NodeGraphQt.qgraphics.node_backdrop import BackdropNodeItem
 from NodeGraphQt.qgraphics.pipe import Pipe
 from NodeGraphQt.qgraphics.port import PortItem
+from NodeGraphQt.qgraphics.slicer import SlicerPipe
 from NodeGraphQt.widgets.scene import NodeScene
 from NodeGraphQt.widgets.stylesheet import STYLE_QMENU
 from NodeGraphQt.widgets.tab_search import TabSearchWidget
@@ -30,6 +31,7 @@ class NodeViewer(QtWidgets.QGraphicsView):
 
     moved_nodes = QtCore.Signal(dict)
     search_triggered = QtCore.Signal(str, tuple)
+    connection_sliced = QtCore.Signal(list)
     connection_changed = QtCore.Signal(list, list)
 
     # pass through signals
@@ -63,6 +65,10 @@ def __init__(self, parent=None):
         self._rubber_band = QtWidgets.QRubberBand(
             QtWidgets.QRubberBand.Rectangle, self
         )
+        self._pipe_slicer = SlicerPipe()
+        self._pipe_slicer.setVisible(False)
+        self.scene().addItem(self._pipe_slicer)
+
         self._undo_stack = QtWidgets.QUndoStack(self)
         self._context_menu = QtWidgets.QMenu('main', self)
         self._context_menu.setStyleSheet(STYLE_QMENU)
@@ -126,6 +132,12 @@ def _on_search_submitted(self, node_type):
         pos = self.mapToScene(self._previous_pos)
         self.search_triggered.emit(node_type, (pos.x(), pos.y()))
 
+    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)
+        ])
+
     # --- reimplemented events ---
 
     def resizeEvent(self, event):
@@ -138,6 +150,7 @@ def contextMenuEvent(self, 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:
@@ -152,10 +165,19 @@ def mousePressEvent(self, event):
         if self._search_widget.isVisible():
             self.tab_search_toggle()
 
+        # cursor pos.
+        map_pos = self.mapToScene(event.pos())
+
+        # pipe slicer enabled.
+        if event.modifiers() == (QtCore.Qt.AltModifier | QtCore.Qt.ShiftModifier):
+            self._pipe_slicer.draw_path(map_pos, map_pos)
+            self._pipe_slicer.setVisible(True)
+            return
+
         if alt_modifier:
             return
 
-        items = self._items_near(self.mapToScene(event.pos()), None, 20, 20)
+        items = self._items_near(map_pos, None, 20, 20)
         nodes = [i for i in items if isinstance(i, AbstractNodeItem)]
 
         # toggle extend node selection.
@@ -188,6 +210,13 @@ def mouseReleaseEvent(self, event):
         elif event.button() == QtCore.Qt.MiddleButton:
             self.MMB_state = False
 
+        # hide pipe slicer.
+        if self._pipe_slicer.isVisible():
+            self._on_pipes_sliced(self._pipe_slicer.path())
+            p = QtCore.QPointF(0.0, 0.0)
+            self._pipe_slicer.draw_path(p, p)
+            self._pipe_slicer.setVisible(False)
+
         # hide selection marquee
         if self._rubber_band.isVisible():
             rect = self._rubber_band.rect()
@@ -211,6 +240,15 @@ def mouseReleaseEvent(self, 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:
+                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
+
         if self.MMB_state and alt_modifier:
             pos_x = (event.x() - self._previous_pos.x())
             zoom = 0.1 if pos_x > 0 else -0.1
@@ -296,6 +334,10 @@ def sceneMousePressEvent(self, event):
             event (QtWidgets.QGraphicsScenePressEvent):
                 The event handler from the QtWidgets.QGraphicsScene
         """
+        # pipe slicer enabled.
+        if event.modifiers() == (QtCore.Qt.AltModifier | QtCore.Qt.ShiftModifier):
+            return
+        # viewer pan mode.
         if event.modifiers() == QtCore.Qt.AltModifier:
             return
 

docs/_static/ngqt.css

@@ -43,7 +43,8 @@ code span.pre {
 }
 
 /* tables */
-table.docutils td, table.docutils th {
+table.docutils td, 
+table.docutils th {
     padding: 4px 8px;
     border-top: 0;
     border-left: 0;
@@ -52,6 +53,10 @@ table.docutils td, table.docutils th {
     background: #24272b;
 }
 
+table.align-center {
+    margin-left: unset;
+}
+
 /*-----------------------------------------*/
 
 /* modules index */

docs/overview.rst

@@ -17,6 +17,21 @@ Navigation
 | Pan           | *Alt + LMB + Drag* or *MMB + Drag*           |
 +---------------+----------------------------------------------+
 
+Port Connections
+================
+
+.. image:: _images/slicer.png
+    :width: 600px
+
+Connection pipes can be disconnected easily with the built in slice tool.
+
++---------------------+----------------------------+
+| action              | controls                   |
++=====================+============================+
+| Slice connections   | *Alt + Shift + LMB + Drag* |
++---------------------+----------------------------+
+
+
 Node Search
 ===========
 

requirements.txt

@@ -1,3 +1,3 @@
 PySide2>=5.12
 Qt.py>=1.2.0.b2
-python>=3.6
+python>=3.6

setup.py

@@ -2,11 +2,14 @@
 # -*- coding: utf-8 -*-
 import setuptools
 
-from NodeGraphQt import __version__ as version
+import NodeGraphQt
 
 with open('README.md', 'r') as fh:
     long_description = fh.read()
 
+with open('requirements.txt') as f:
+    requirements = f.read().splitlines()
+
 description = (
     'Node graph framework that can be re-implemented into applications that '
     'supports PySide & PySide2'
@@ -19,7 +22,8 @@
 
 setuptools.setup(
     name='NodeGraphQt',
-    version=version,
+    version=NodeGraphQt.__version__,
+    install_requires=requirements,
     author='Johnny Chan',
     author_email='johnny@chantasticvfx.com',
     description=description,
@@ -28,7 +32,7 @@
     url='https://github.com/jchanvfx/NodeGraphQt',
     packages=setuptools.find_packages(exclude=["example_nodes"]),
     classifiers=classifiers,
-    include_package_data=True,
+    include_package_data=True
 )