class LinkItem(QGraphicsObject):
"""
A Link item in the canvas that connects two :class:`.NodeItem`\s in the
canvas.
The link curve connects two `Anchor` items (see :func:`setSourceItem`
and :func:`setSinkItem`). Once the anchors are set the curve
automatically adjusts its end points whenever the anchors move.
An optional source/sink text item can be displayed above the curve's
central point (:func:`setSourceName`, :func:`setSinkName`)
"""
#: Z value of the item
Z_VALUE = 0
#: Runtime link state value
#: These are pulled from SchemeLink.State for ease of binding to it's
#: state
State = SchemeLink.State
#: The link has no associated state.
NoState = SchemeLink.NoState
#: Link is empty; the source node does not have any value on output
Empty = SchemeLink.Empty
#: Link is active; the source node has a valid value on output
Active = SchemeLink.Active
#: The link is pending; the sink node is scheduled for update
Pending = SchemeLink.Pending
def __init__(self, *args):
self.__boundingRect = None
QGraphicsObject.__init__(self, *args)
self.setFlag(QGraphicsItem.ItemHasNoContents, True)
self.setAcceptedMouseButtons(Qt.RightButton | Qt.LeftButton)
self.setAcceptHoverEvents(True)
self.setZValue(self.Z_VALUE)
self.sourceItem = None
self.sourceAnchor = None
self.sinkItem = None
self.sinkAnchor = None
self.curveItem = LinkCurveItem(self)
self.sourceIndicator = LinkAnchorIndicator(self)
self.sinkIndicator = LinkAnchorIndicator(self)
self.sourceIndicator.hide()
self.sinkIndicator.hide()
self.linkTextItem = QGraphicsTextItem(self)
self.linkTextItem.setAcceptedMouseButtons(Qt.NoButton)
self.linkTextItem.setAcceptHoverEvents(False)
self.__sourceName = ""
self.__sinkName = ""
self.__dynamic = False
self.__dynamicEnabled = False
self.__state = LinkItem.NoState
self.hover = False
self.prepareGeometryChange()
self.__updatePen()
self.__boundingRect = None
def setSourceItem(self, item, anchor=None):
"""
Set the source `item` (:class:`.NodeItem`). Use `anchor`
(:class:`.AnchorPoint`) as the curve start point (if ``None`` a new
output anchor will be created using ``item.newOutputAnchor()``).
Setting item to ``None`` and a valid anchor is a valid operation
(for instance while mouse dragging one end of the link).
"""
if item is not None and anchor is not None:
if anchor not in item.outputAnchors():
raise ValueError("Anchor must be belong to the item")
if self.sourceItem != item:
if self.sourceAnchor:
# Remove a previous source item and the corresponding anchor
self.sourceAnchor.scenePositionChanged.disconnect(
self._sourcePosChanged
)
if self.sourceItem is not None:
self.sourceItem.removeOutputAnchor(self.sourceAnchor)
self.sourceItem = self.sourceAnchor = None
self.sourceItem = item
if item is not None and anchor is None:
# Create a new output anchor for the item if none is provided.
anchor = item.newOutputAnchor()
# Update the visibility of the start point indicator.
self.sourceIndicator.setVisible(bool(item))
if anchor != self.sourceAnchor:
if self.sourceAnchor is not None:
self.sourceAnchor.scenePositionChanged.disconnect(
self._sourcePosChanged
)
self.sourceAnchor = anchor
if self.sourceAnchor is not None:
self.sourceAnchor.scenePositionChanged.connect(
self._sourcePosChanged
)
self.__updateCurve()
def setSinkItem(self, item, anchor=None):
"""
Set the sink `item` (:class:`.NodeItem`). Use `anchor`
(:class:`.AnchorPoint`) as the curve end point (if ``None`` a new
input anchor will be created using ``item.newInputAnchor()``).
Setting item to ``None`` and a valid anchor is a valid operation
(for instance while mouse dragging one and of the link).
"""
if item is not None and anchor is not None:
if anchor not in item.inputAnchors():
raise ValueError("Anchor must be belong to the item")
if self.sinkItem != item:
if self.sinkAnchor:
# Remove a previous source item and the corresponding anchor
self.sinkAnchor.scenePositionChanged.disconnect(
self._sinkPosChanged
)
if self.sinkItem is not None:
self.sinkItem.removeInputAnchor(self.sinkAnchor)
self.sinkItem = self.sinkAnchor = None
self.sinkItem = item
if item is not None and anchor is None:
# Create a new input anchor for the item if none is provided.
anchor = item.newInputAnchor()
# Update the visibility of the end point indicator.
self.sinkIndicator.setVisible(bool(item))
if self.sinkAnchor != anchor:
if self.sinkAnchor is not None:
self.sinkAnchor.scenePositionChanged.disconnect(
self._sinkPosChanged
)
self.sinkAnchor = anchor
if self.sinkAnchor is not None:
self.sinkAnchor.scenePositionChanged.connect(
self._sinkPosChanged
)
self.__updateCurve()
def setFont(self, font):
"""
Set the font for the channel names text item.
"""
if font != self.font():
self.linkTextItem.setFont(font)
self.__updateText()
def font(self):
"""
Return the font for the channel names text.
"""
return self.linkTextItem.font()
def setChannelNamesVisible(self, visible):
"""
Set the visibility of the channel name text.
"""
self.linkTextItem.setVisible(visible)
def setSourceName(self, name):
"""
Set the name of the source (used in channel name text).
"""
if self.__sourceName != name:
self.__sourceName = name
self.__updateText()
def sourceName(self):
"""
Return the source name.
"""
return self.__sourceName
def setSinkName(self, name):
"""
Set the name of the sink (used in channel name text).
"""
if self.__sinkName != name:
self.__sinkName = name
self.__updateText()
def sinkName(self):
"""
Return the sink name.
"""
return self.__sinkName
def _sinkPosChanged(self, *arg):
self.__updateCurve()
def _sourcePosChanged(self, *arg):
self.__updateCurve()
def __updateCurve(self):
self.prepareGeometryChange()
self.__boundingRect = None
if self.sourceAnchor and self.sinkAnchor:
source_pos = self.sourceAnchor.anchorScenePos()
sink_pos = self.sinkAnchor.anchorScenePos()
source_pos = self.curveItem.mapFromScene(source_pos)
sink_pos = self.curveItem.mapFromScene(sink_pos)
# Adaptive offset for the curve control points to avoid a
# cusp when the two points have the same y coordinate
# and are close together
delta = source_pos - sink_pos
dist = math.sqrt(delta.x() ** 2 + delta.y() ** 2)
cp_offset = min(dist / 2.0, 60.0)
# TODO: make the curve tangent orthogonal to the anchors path.
path = QPainterPath()
path.moveTo(source_pos)
path.cubicTo(source_pos + QPointF(cp_offset, 0),
sink_pos - QPointF(cp_offset, 0),
sink_pos)
self.curveItem.setCurvePath(path)
self.sourceIndicator.setPos(source_pos)
self.sinkIndicator.setPos(sink_pos)
self.__updateText()
else:
self.setHoverState(False)
self.curveItem.setPath(QPainterPath())
def __updateText(self):
self.prepareGeometryChange()
self.__boundingRect = None
if self.__sourceName or self.__sinkName:
if self.__sourceName != self.__sinkName:
text = ("<nobr>{0}</nobr> \u2192 <nobr>{1}</nobr>"
.format(escape(self.__sourceName),
escape(self.__sinkName)))
else:
# If the names are the same show only one.
# Is this right? If the sink has two input channels of the
# same type having the name on the link help elucidate
# the scheme.
text = escape(self.__sourceName)
else:
text = ""
self.linkTextItem.setHtml('<div align="center">{0}</div>'
.format(text))
path = self.curveItem.curvePath()
# Constrain the text width if it is too long to fit on a single line
# between the two ends
if not path.isEmpty():
# Use the distance between the start/end points as a measure of
# available space
diff = path.pointAtPercent(0.0) - path.pointAtPercent(1.0)
available_width = math.sqrt(diff.x() ** 2 + diff.y() ** 2)
# Get the ideal text width if it was unconstrained
doc = self.linkTextItem.document().clone(self)
doc.setTextWidth(-1)
idealwidth = doc.idealWidth()
doc.deleteLater()
# Constrain the text width but not below a certain min width
minwidth = 100
textwidth = max(minwidth, min(available_width, idealwidth))
self.linkTextItem.setTextWidth(textwidth)
else:
# Reset the fixed width
self.linkTextItem.setTextWidth(-1)
if not path.isEmpty():
center = path.pointAtPercent(0.5)
angle = path.angleAtPercent(0.5)
brect = self.linkTextItem.boundingRect()
transform = QTransform()
transform.translate(center.x(), center.y())
transform.rotate(-angle)
# Center and move above the curve path.
transform.translate(-brect.width() / 2, -brect.height())
self.linkTextItem.setTransform(transform)
def removeLink(self):
self.setSinkItem(None)
self.setSourceItem(None)
self.__updateCurve()
def setHoverState(self, state):
if self.hover != state:
self.prepareGeometryChange()
self.__boundingRect = None
self.hover = state
self.sinkIndicator.setHoverState(state)
self.sourceIndicator.setHoverState(state)
self.curveItem.setHoverState(state)
self.__updatePen()
def hoverEnterEvent(self, event):
# Hover enter event happens when the mouse enters any child object
# but we only want to show the 'hovered' shadow when the mouse
# is over the 'curveItem', so we install self as an event filter
# on the LinkCurveItem and listen to its hover events.
self.curveItem.installSceneEventFilter(self)
return QGraphicsObject.hoverEnterEvent(self, event)
def hoverLeaveEvent(self, event):
# Remove the event filter to prevent unnecessary work in
# scene event filter when not needed
self.curveItem.removeSceneEventFilter(self)
return QGraphicsObject.hoverLeaveEvent(self, event)
def sceneEventFilter(self, obj, event):
if obj is self.curveItem:
if event.type() == QEvent.GraphicsSceneHoverEnter:
self.setHoverState(True)
elif event.type() == QEvent.GraphicsSceneHoverLeave:
self.setHoverState(False)
return QGraphicsObject.sceneEventFilter(self, obj, event)
def boundingRect(self):
if self.__boundingRect is None:
self.__boundingRect = self.childrenBoundingRect()
return self.__boundingRect
def shape(self):
return self.curveItem.shape()
def setEnabled(self, enabled):
"""
Reimplemented from :class:`QGraphicsObject`
Set link enabled state. When disabled the link is rendered with a
dashed line.
"""
# This getter/setter pair override a property from the base class.
# They should be renamed to e.g. setLinkEnabled/linkEnabled
self.curveItem.setLinkEnabled(enabled)
def isEnabled(self):
return self.curveItem.isLinkEnabled()
def setDynamicEnabled(self, enabled):
"""
Set the link's dynamic enabled state.
If the link is `dynamic` it will be rendered in red/green color
respectively depending on the state of the dynamic enabled state.
"""
if self.__dynamicEnabled != enabled:
self.__dynamicEnabled = enabled
if self.__dynamic:
self.__updatePen()
def isDynamicEnabled(self):
"""
Is the link dynamic enabled.
"""
return self.__dynamicEnabled
def setDynamic(self, dynamic):
"""
Mark the link as dynamic (i.e. it responds to
:func:`setDynamicEnabled`).
"""
if self.__dynamic != dynamic:
self.__dynamic = dynamic
self.__updatePen()
def isDynamic(self):
"""
Is the link dynamic.
"""
return self.__dynamic
def setRuntimeState(self, state):
"""
Style the link appropriate to the LinkItem.State
Parameters
----------
state : LinkItem.State
"""
if self.__state != state:
self.__state = state
if state & LinkItem.Pending:
self.sinkIndicator.setBrush(QBrush(Qt.yellow))
else:
self.sinkIndicator.setBrush(QBrush(QColor("#9CACB4")))
self.__updatePen()
def runtimeState(self):
return self.__state
def __updatePen(self):
self.prepareGeometryChange()
self.__boundingRect = None
if self.__dynamic:
if self.__dynamicEnabled:
color = QColor(0, 150, 0, 150)
else:
color = QColor(150, 0, 0, 150)
normal = QPen(QBrush(color), 2.0)
hover = QPen(QBrush(color.darker(120)), 2.1)
else:
normal = QPen(QBrush(QColor("#9CACB4")), 2.0)
hover = QPen(QBrush(QColor("#7D7D7D")), 2.1)
if self.__state & LinkItem.Empty:
pen_style = Qt.DashLine
else:
pen_style = Qt.SolidLine
normal.setStyle(pen_style)
hover.setStyle(pen_style)
if self.hover:
pen = hover
else:
pen = normal
self.curveItem.setPen(pen)
class OWAxis(QGraphicsItem):
Role = OWPalette.Axis
def __init__(self,
id,
title='',
title_above=False,
title_location=AxisMiddle,
line=None,
arrows=0,
plot=None,
bounds=None):
QGraphicsItem.__init__(self)
self.setFlag(QGraphicsItem.ItemHasNoContents)
self.setZValue(AxisZValue)
self.id = id
self.title = title
self.title_location = title_location
self.data_line = line
self.plot = plot
self.graph_line = None
self.size = None
self.scale = None
self.tick_length = (10, 5, 0)
self.arrows = arrows
self.title_above = title_above
self.line_item = QGraphicsLineItem(self)
self.title_item = QGraphicsTextItem(self)
self.end_arrow_item = None
self.start_arrow_item = None
self.show_title = False
self.scale = None
path = QPainterPath()
path.setFillRule(Qt.WindingFill)
path.moveTo(0, 3.09)
path.lineTo(0, -3.09)
path.lineTo(9.51, 0)
path.closeSubpath()
self.arrow_path = path
self.label_items = []
self.label_bg_items = []
self.tick_items = []
self._ticks = []
self.zoom_transform = QTransform()
self.labels = None
self.values = None
self._bounds = bounds
self.auto_range = None
self.auto_scale = True
self.zoomable = False
self.update_callback = None
self.max_text_width = 50
self.text_margin = 5
self.always_horizontal_text = False
@staticmethod
def compute_scale(min, max):
magnitude = int(3 * log10(abs(max - min)) + 1)
if magnitude % 3 == 0:
first_place = 1
elif magnitude % 3 == 1:
first_place = 2
else:
first_place = 5
magnitude = magnitude // 3 - 1
step = first_place * pow(10, magnitude)
first_val = ceil(min / step) * step
return first_val, step
def update_ticks(self):
self._ticks = []
major, medium, minor = self.tick_length
if self.labels is not None and not self.auto_scale:
values = self.values or range(len(self.labels))
for i, text in zip(values, self.labels):
self._ticks.append((i, text, medium, 1))
else:
if self.scale and not self.auto_scale:
min, max, step = self.scale
elif self.auto_range:
min, max = self.auto_range
if min is not None and max is not None:
step = (max - min) / 10
else:
return
else:
return
if max == min:
return
val, step = self.compute_scale(min, max)
while val <= max:
self._ticks.append((val, "%.4g" % val, medium, step))
val += step
def update_graph(self):
if self.update_callback:
self.update_callback()
def update(self, zoom_only=False):
self.update_ticks()
line_color = self.plot.color(OWPalette.Axis)
text_color = self.plot.color(OWPalette.Text)
if not self.graph_line or not self.scene():
return
self.line_item.setLine(self.graph_line)
self.line_item.setPen(line_color)
if self.title:
self.title_item.setHtml('<b>' + self.title + '</b>')
self.title_item.setDefaultTextColor(text_color)
if self.title_location == AxisMiddle:
title_p = 0.5
elif self.title_location == AxisEnd:
title_p = 0.95
else:
title_p = 0.05
title_pos = self.graph_line.pointAt(title_p)
v = self.graph_line.normalVector().unitVector()
dense_text = False
if hasattr(self, 'title_margin'):
offset = self.title_margin
elif self._ticks:
if self.should_be_expanded():
offset = 55
dense_text = True
else:
offset = 35
else:
offset = 10
if self.title_above:
title_pos += (v.p2() - v.p1()) * (
offset + QFontMetrics(self.title_item.font()).height())
else:
title_pos -= (v.p2() - v.p1()) * offset
## TODO: Move it according to self.label_pos
self.title_item.setVisible(self.show_title)
self.title_item.setRotation(-self.graph_line.angle())
c = self.title_item.mapToParent(
self.title_item.boundingRect().center())
tl = self.title_item.mapToParent(
self.title_item.boundingRect().topLeft())
self.title_item.setPos(title_pos - c + tl)
## Arrows
if not zoom_only:
if self.start_arrow_item:
self.scene().removeItem(self.start_arrow_item)
self.start_arrow_item = None
if self.end_arrow_item:
self.scene().removeItem(self.end_arrow_item)
self.end_arrow_item = None
if self.arrows & AxisStart:
if not zoom_only or not self.start_arrow_item:
self.start_arrow_item = QGraphicsPathItem(
self.arrow_path, self)
self.start_arrow_item.setPos(self.graph_line.p1())
self.start_arrow_item.setRotation(-self.graph_line.angle() + 180)
self.start_arrow_item.setBrush(line_color)
self.start_arrow_item.setPen(line_color)
if self.arrows & AxisEnd:
if not zoom_only or not self.end_arrow_item:
self.end_arrow_item = QGraphicsPathItem(self.arrow_path, self)
self.end_arrow_item.setPos(self.graph_line.p2())
self.end_arrow_item.setRotation(-self.graph_line.angle())
self.end_arrow_item.setBrush(line_color)
self.end_arrow_item.setPen(line_color)
## Labels
n = len(self._ticks)
resize_plot_item_list(self.label_items, n, QGraphicsTextItem, self)
resize_plot_item_list(self.label_bg_items, n, QGraphicsRectItem, self)
resize_plot_item_list(self.tick_items, n, QGraphicsLineItem, self)
test_rect = QRectF(self.graph_line.p1(),
self.graph_line.p2()).normalized()
test_rect.adjust(-1, -1, 1, 1)
n_v = self.graph_line.normalVector().unitVector()
if self.title_above:
n_p = n_v.p2() - n_v.p1()
else:
n_p = n_v.p1() - n_v.p2()
l_v = self.graph_line.unitVector()
l_p = l_v.p2() - l_v.p1()
for i in range(n):
pos, text, size, step = self._ticks[i]
hs = 0.5 * step
tick_pos = self.map_to_graph(pos)
if not test_rect.contains(tick_pos):
self.tick_items[i].setVisible(False)
self.label_items[i].setVisible(False)
continue
item = self.label_items[i]
item.setVisible(True)
if not zoom_only:
if self.id in XAxes or getattr(self, 'is_horizontal', False):
item.setHtml('<center>' + Qt.escape(text.strip()) +
'</center>')
else:
item.setHtml(Qt.escape(text.strip()))
item.setTextWidth(-1)
text_angle = 0
if dense_text:
w = min(item.boundingRect().width(), self.max_text_width)
item.setTextWidth(w)
if self.title_above:
label_pos = tick_pos + n_p * (
w + self.text_margin
) + l_p * item.boundingRect().height() / 2
else:
label_pos = tick_pos + n_p * self.text_margin + l_p * item.boundingRect(
).height() / 2
text_angle = -90 if self.title_above else 90
else:
w = min(
item.boundingRect().width(),
QLineF(self.map_to_graph(pos - hs),
self.map_to_graph(pos + hs)).length())
label_pos = tick_pos + n_p * self.text_margin + l_p * item.boundingRect(
).height() / 2
item.setTextWidth(w)
if not self.always_horizontal_text:
if self.title_above:
item.setRotation(-self.graph_line.angle() - text_angle)
else:
item.setRotation(self.graph_line.angle() - text_angle)
item.setPos(label_pos)
item.setDefaultTextColor(text_color)
self.label_bg_items[i].setRect(item.boundingRect())
self.label_bg_items[i].setPen(QPen(Qt.NoPen))
self.label_bg_items[i].setBrush(self.plot.color(OWPalette.Canvas))
item = self.tick_items[i]
item.setVisible(True)
tick_line = QLineF(v)
tick_line.translate(-tick_line.p1())
tick_line.setLength(size)
if self.title_above:
tick_line.setAngle(tick_line.angle() + 180)
item.setLine(tick_line)
item.setPen(line_color)
item.setPos(self.map_to_graph(pos))
@staticmethod
def make_title(label, unit=None):
lab = '<i>' + label + '</i>'
if unit:
lab = lab + ' [' + unit + ']'
return lab
def set_line(self, line):
self.graph_line = line
self.update()
def set_title(self, title):
self.title = title
self.update()
def set_show_title(self, b):
self.show_title = b
self.update()
def set_labels(self, labels, values):
self.labels = labels
self.values = values
self.graph_line = None
self.auto_scale = False
self.update_ticks()
self.update_graph()
def set_scale(self, min, max, step_size):
self.scale = (min, max, step_size)
self.graph_line = None
self.auto_scale = False
self.update_ticks()
self.update_graph()
def set_tick_length(self, minor, medium, major):
self.tick_length = (minor, medium, major)
self.update()
def map_to_graph(self, x):
min, max = self.plot.bounds_for_axis(self.id)
if min == max:
return QPointF()
line_point = self.graph_line.pointAt((x - min) / (max - min))
end_point = line_point * self.zoom_transform
return self.projection(end_point, self.graph_line)
@staticmethod
def projection(point, line):
norm = line.normalVector()
norm.translate(point - norm.p1())
p = QPointF()
type = line.intersect(norm, p)
return p
def continuous_labels(self):
min, max, step = self.scale
magnitude = log10(abs(max - min))
def paint(self, painter, option, widget):
pass
def boundingRect(self):
return QRectF()
def ticks(self):
if not self._ticks:
self.update_ticks()
return self._ticks
def bounds(self):
if self._bounds:
return self._bounds
if self.labels:
return -0.2, len(self.labels) - 0.8
elif self.scale:
min, max, _step = self.scale
return min, max
elif self.auto_range:
return self.auto_range
else:
return 0, 1
def set_bounds(self, value):
self._bounds = value
def should_be_expanded(self):
self.update_ticks()
return self.id in YAxes or self.always_horizontal_text or sum(
len(t[1]) for t in self._ticks) * 12 > self.plot.width()
class LinkItem(QGraphicsWidget):
"""
A Link item in the canvas that connects two :class:`.NodeItem`\s in the
canvas.
The link curve connects two `Anchor` items (see :func:`setSourceItem`
and :func:`setSinkItem`). Once the anchors are set the curve
automatically adjusts its end points whenever the anchors move.
An optional source/sink text item can be displayed above the curve's
central point (:func:`setSourceName`, :func:`setSinkName`)
"""
#: Z value of the item
Z_VALUE = 0
#: Runtime link state value
#: These are pulled from SchemeLink.State for ease of binding to it's
#: state
State = SchemeLink.State
#: The link has no associated state.
NoState = SchemeLink.NoState
#: Link is empty; the source node does not have any value on output
Empty = SchemeLink.Empty
#: Link is active; the source node has a valid value on output
Active = SchemeLink.Active
#: The link is pending; the sink node is scheduled for update
Pending = SchemeLink.Pending
def __init__(self, *args):
self.__boundingRect = None
super().__init__(*args)
self.setFlag(QGraphicsItem.ItemHasNoContents, True)
self.setAcceptedMouseButtons(Qt.RightButton | Qt.LeftButton)
self.setAcceptHoverEvents(True)
self.setZValue(self.Z_VALUE)
self.sourceItem = None
self.sourceAnchor = None
self.sinkItem = None
self.sinkAnchor = None
self.curveItem = LinkCurveItem(self)
self.sourceIndicator = LinkAnchorIndicator(self)
self.sinkIndicator = LinkAnchorIndicator(self)
self.sourceIndicator.hide()
self.sinkIndicator.hide()
self.linkTextItem = QGraphicsTextItem(self)
self.linkTextItem.setAcceptedMouseButtons(Qt.NoButton)
self.linkTextItem.setAcceptHoverEvents(False)
self.__sourceName = ""
self.__sinkName = ""
self.__dynamic = False
self.__dynamicEnabled = False
self.__state = LinkItem.NoState
self.hover = False
self.prepareGeometryChange()
self.__updatePen()
self.__boundingRect = None
self.__updatePalette()
self.__updateFont()
def setSourceItem(self, item, anchor=None):
"""
Set the source `item` (:class:`.NodeItem`). Use `anchor`
(:class:`.AnchorPoint`) as the curve start point (if ``None`` a new
output anchor will be created using ``item.newOutputAnchor()``).
Setting item to ``None`` and a valid anchor is a valid operation
(for instance while mouse dragging one end of the link).
"""
if item is not None and anchor is not None:
if anchor not in item.outputAnchors():
raise ValueError("Anchor must be belong to the item")
if self.sourceItem != item:
if self.sourceAnchor:
# Remove a previous source item and the corresponding anchor
self.sourceAnchor.scenePositionChanged.disconnect(
self._sourcePosChanged
)
if self.sourceItem is not None:
self.sourceItem.removeOutputAnchor(self.sourceAnchor)
self.sourceItem = self.sourceAnchor = None
self.sourceItem = item
if item is not None and anchor is None:
# Create a new output anchor for the item if none is provided.
anchor = item.newOutputAnchor()
# Update the visibility of the start point indicator.
self.sourceIndicator.setVisible(bool(item))
if anchor != self.sourceAnchor:
if self.sourceAnchor is not None:
self.sourceAnchor.scenePositionChanged.disconnect(
self._sourcePosChanged
)
self.sourceAnchor = anchor
if self.sourceAnchor is not None:
self.sourceAnchor.scenePositionChanged.connect(
self._sourcePosChanged
)
self.__updateCurve()
def setSinkItem(self, item, anchor=None):
"""
Set the sink `item` (:class:`.NodeItem`). Use `anchor`
(:class:`.AnchorPoint`) as the curve end point (if ``None`` a new
input anchor will be created using ``item.newInputAnchor()``).
Setting item to ``None`` and a valid anchor is a valid operation
(for instance while mouse dragging one and of the link).
"""
if item is not None and anchor is not None:
if anchor not in item.inputAnchors():
raise ValueError("Anchor must be belong to the item")
if self.sinkItem != item:
if self.sinkAnchor:
# Remove a previous source item and the corresponding anchor
self.sinkAnchor.scenePositionChanged.disconnect(
self._sinkPosChanged
)
if self.sinkItem is not None:
self.sinkItem.removeInputAnchor(self.sinkAnchor)
self.sinkItem = self.sinkAnchor = None
self.sinkItem = item
if item is not None and anchor is None:
# Create a new input anchor for the item if none is provided.
anchor = item.newInputAnchor()
# Update the visibility of the end point indicator.
self.sinkIndicator.setVisible(bool(item))
if self.sinkAnchor != anchor:
if self.sinkAnchor is not None:
self.sinkAnchor.scenePositionChanged.disconnect(
self._sinkPosChanged
)
self.sinkAnchor = anchor
if self.sinkAnchor is not None:
self.sinkAnchor.scenePositionChanged.connect(
self._sinkPosChanged
)
self.__updateCurve()
def setChannelNamesVisible(self, visible):
"""
Set the visibility of the channel name text.
"""
self.linkTextItem.setVisible(visible)
def setSourceName(self, name):
"""
Set the name of the source (used in channel name text).
"""
if self.__sourceName != name:
self.__sourceName = name
self.__updateText()
def sourceName(self):
"""
Return the source name.
"""
return self.__sourceName
def setSinkName(self, name):
"""
Set the name of the sink (used in channel name text).
"""
if self.__sinkName != name:
self.__sinkName = name
self.__updateText()
def sinkName(self):
"""
Return the sink name.
"""
return self.__sinkName
def _sinkPosChanged(self, *arg):
self.__updateCurve()
def _sourcePosChanged(self, *arg):
self.__updateCurve()
def __updateCurve(self):
self.prepareGeometryChange()
self.__boundingRect = None
if self.sourceAnchor and self.sinkAnchor:
source_pos = self.sourceAnchor.anchorScenePos()
sink_pos = self.sinkAnchor.anchorScenePos()
source_pos = self.curveItem.mapFromScene(source_pos)
sink_pos = self.curveItem.mapFromScene(sink_pos)
# Adaptive offset for the curve control points to avoid a
# cusp when the two points have the same y coordinate
# and are close together
delta = source_pos - sink_pos
dist = math.sqrt(delta.x() ** 2 + delta.y() ** 2)
cp_offset = min(dist / 2.0, 60.0)
# TODO: make the curve tangent orthogonal to the anchors path.
path = QPainterPath()
path.moveTo(source_pos)
path.cubicTo(source_pos + QPointF(cp_offset, 0),
sink_pos - QPointF(cp_offset, 0),
sink_pos)
self.curveItem.setCurvePath(path)
self.sourceIndicator.setPos(source_pos)
self.sinkIndicator.setPos(sink_pos)
self.__updateText()
else:
self.setHoverState(False)
self.curveItem.setPath(QPainterPath())
def __updateText(self):
self.prepareGeometryChange()
self.__boundingRect = None
if self.__sourceName or self.__sinkName:
if self.__sourceName != self.__sinkName:
text = ("<nobr>{0}</nobr> \u2192 <nobr>{1}</nobr>"
.format(escape(self.__sourceName),
escape(self.__sinkName)))
else:
# If the names are the same show only one.
# Is this right? If the sink has two input channels of the
# same type having the name on the link help elucidate
# the scheme.
text = escape(self.__sourceName)
else:
text = ""
self.linkTextItem.setHtml('<div align="center">{0}</div>'
.format(text))
path = self.curveItem.curvePath()
# Constrain the text width if it is too long to fit on a single line
# between the two ends
if not path.isEmpty():
# Use the distance between the start/end points as a measure of
# available space
diff = path.pointAtPercent(0.0) - path.pointAtPercent(1.0)
available_width = math.sqrt(diff.x() ** 2 + diff.y() ** 2)
# Get the ideal text width if it was unconstrained
doc = self.linkTextItem.document().clone(self)
doc.setTextWidth(-1)
idealwidth = doc.idealWidth()
doc.deleteLater()
# Constrain the text width but not below a certain min width
minwidth = 100
textwidth = max(minwidth, min(available_width, idealwidth))
self.linkTextItem.setTextWidth(textwidth)
else:
# Reset the fixed width
self.linkTextItem.setTextWidth(-1)
if not path.isEmpty():
center = path.pointAtPercent(0.5)
angle = path.angleAtPercent(0.5)
brect = self.linkTextItem.boundingRect()
transform = QTransform()
transform.translate(center.x(), center.y())
transform.rotate(-angle)
# Center and move above the curve path.
transform.translate(-brect.width() / 2, -brect.height())
self.linkTextItem.setTransform(transform)
def removeLink(self):
self.setSinkItem(None)
self.setSourceItem(None)
self.__updateCurve()
def setHoverState(self, state):
if self.hover != state:
self.prepareGeometryChange()
self.__boundingRect = None
self.hover = state
self.sinkIndicator.setHoverState(state)
self.sourceIndicator.setHoverState(state)
self.curveItem.setHoverState(state)
self.__updatePen()
def hoverEnterEvent(self, event):
# Hover enter event happens when the mouse enters any child object
# but we only want to show the 'hovered' shadow when the mouse
# is over the 'curveItem', so we install self as an event filter
# on the LinkCurveItem and listen to its hover events.
self.curveItem.installSceneEventFilter(self)
return super().hoverEnterEvent(event)
def hoverLeaveEvent(self, event):
# Remove the event filter to prevent unnecessary work in
# scene event filter when not needed
self.curveItem.removeSceneEventFilter(self)
return super().hoverLeaveEvent(event)
def changeEvent(self, event):
if event.type() == QEvent.PaletteChange:
self.__updatePalette()
elif event.type() == QEvent.FontChange:
self.__updateFont()
super().changeEvent(event)
def sceneEventFilter(self, obj, event):
if obj is self.curveItem:
if event.type() == QEvent.GraphicsSceneHoverEnter:
self.setHoverState(True)
elif event.type() == QEvent.GraphicsSceneHoverLeave:
self.setHoverState(False)
return super().sceneEventFilter(obj, event)
def boundingRect(self):
if self.__boundingRect is None:
self.__boundingRect = self.childrenBoundingRect()
return self.__boundingRect
def shape(self):
return self.curveItem.shape()
def setEnabled(self, enabled):
"""
Reimplemented from :class:`QGraphicWidget`
Set link enabled state. When disabled the link is rendered with a
dashed line.
"""
# This getter/setter pair override a property from the base class.
# They should be renamed to e.g. setLinkEnabled/linkEnabled
self.curveItem.setLinkEnabled(enabled)
def isEnabled(self):
return self.curveItem.isLinkEnabled()
def setDynamicEnabled(self, enabled):
"""
Set the link's dynamic enabled state.
If the link is `dynamic` it will be rendered in red/green color
respectively depending on the state of the dynamic enabled state.
"""
if self.__dynamicEnabled != enabled:
self.__dynamicEnabled = enabled
if self.__dynamic:
self.__updatePen()
def isDynamicEnabled(self):
"""
Is the link dynamic enabled.
"""
return self.__dynamicEnabled
def setDynamic(self, dynamic):
"""
Mark the link as dynamic (i.e. it responds to
:func:`setDynamicEnabled`).
"""
if self.__dynamic != dynamic:
self.__dynamic = dynamic
self.__updatePen()
def isDynamic(self):
"""
Is the link dynamic.
"""
return self.__dynamic
def setRuntimeState(self, state):
"""
Style the link appropriate to the LinkItem.State
Parameters
----------
state : LinkItem.State
"""
if self.__state != state:
self.__state = state
if state & LinkItem.Pending:
self.sinkIndicator.setBrush(QBrush(Qt.red))
else:
self.sinkIndicator.setBrush(QBrush(QColor("#9CACB4")))
self.__updatePen()
def runtimeState(self):
return self.__state
def __updatePen(self):
self.prepareGeometryChange()
self.__boundingRect = None
if self.__dynamic:
if self.__dynamicEnabled:
color = QColor(0, 150, 0, 150)
else:
color = QColor(150, 0, 0, 150)
normal = QPen(QBrush(color), 2.0)
hover = QPen(QBrush(color.darker(120)), 2.1)
else:
normal = QPen(QBrush(QColor("#9CACB4")), 2.0)
hover = QPen(QBrush(QColor("#7D7D7D")), 2.1)
if self.__state & LinkItem.Empty:
pen_style = Qt.DashLine
else:
pen_style = Qt.SolidLine
normal.setStyle(pen_style)
hover.setStyle(pen_style)
if self.hover:
pen = hover
else:
pen = normal
self.curveItem.setPen(pen)
def __updatePalette(self):
self.linkTextItem.setDefaultTextColor(
self.palette().color(QPalette.Text))
def __updateFont(self):
self.linkTextItem.setFont(self.font())
class OWAxis(QGraphicsItem):
Role = OWPalette.Axis
def __init__(self, id, title='', title_above=False, title_location=AxisMiddle,
line=None, arrows=0, plot=None, bounds=None):
QGraphicsItem.__init__(self)
self.setFlag(QGraphicsItem.ItemHasNoContents)
self.setZValue(AxisZValue)
self.id = id
self.title = title
self.title_location = title_location
self.data_line = line
self.plot = plot
self.graph_line = None
self.size = None
self.scale = None
self.tick_length = (10, 5, 0)
self.arrows = arrows
self.title_above = title_above
self.line_item = QGraphicsLineItem(self)
self.title_item = QGraphicsTextItem(self)
self.end_arrow_item = None
self.start_arrow_item = None
self.show_title = False
self.scale = None
path = QPainterPath()
path.setFillRule(Qt.WindingFill)
path.moveTo(0, 3.09)
path.lineTo(0, -3.09)
path.lineTo(9.51, 0)
path.closeSubpath()
self.arrow_path = path
self.label_items = []
self.label_bg_items = []
self.tick_items = []
self._ticks = []
self.zoom_transform = QTransform()
self.labels = None
self.values = None
self._bounds = bounds
self.auto_range = None
self.auto_scale = True
self.zoomable = False
self.update_callback = None
self.max_text_width = 50
self.text_margin = 5
self.always_horizontal_text = False
@staticmethod
def compute_scale(min, max):
magnitude = int(3 * log10(abs(max - min)) + 1)
if magnitude % 3 == 0:
first_place = 1
elif magnitude % 3 == 1:
first_place = 2
else:
first_place = 5
magnitude = magnitude // 3 - 1
step = first_place * pow(10, magnitude)
first_val = ceil(min / step) * step
return first_val, step
def update_ticks(self):
self._ticks = []
major, medium, minor = self.tick_length
if self.labels is not None and not self.auto_scale:
values = self.values or range(len(self.labels))
for i, text in zip(values, self.labels):
self._ticks.append((i, text, medium, 1))
else:
if self.scale and not self.auto_scale:
min, max, step = self.scale
elif self.auto_range:
min, max = self.auto_range
if min is not None and max is not None:
step = (max - min) / 10
else:
return
else:
return
if max == min:
return
val, step = self.compute_scale(min, max)
while val <= max:
self._ticks.append((val, "%.4g" % val, medium, step))
val += step
def update_graph(self):
if self.update_callback:
self.update_callback()
def update(self, zoom_only=False):
self.update_ticks()
line_color = self.plot.color(OWPalette.Axis)
text_color = self.plot.color(OWPalette.Text)
if not self.graph_line or not self.scene():
return
self.line_item.setLine(self.graph_line)
self.line_item.setPen(line_color)
if self.title:
self.title_item.setHtml('<b>' + self.title + '</b>')
self.title_item.setDefaultTextColor(text_color)
if self.title_location == AxisMiddle:
title_p = 0.5
elif self.title_location == AxisEnd:
title_p = 0.95
else:
title_p = 0.05
title_pos = self.graph_line.pointAt(title_p)
v = self.graph_line.normalVector().unitVector()
dense_text = False
if hasattr(self, 'title_margin'):
offset = self.title_margin
elif self._ticks:
if self.should_be_expanded():
offset = 55
dense_text = True
else:
offset = 35
else:
offset = 10
if self.title_above:
title_pos += (v.p2() - v.p1()) * (offset + QFontMetrics(self.title_item.font()).height())
else:
title_pos -= (v.p2() - v.p1()) * offset
## TODO: Move it according to self.label_pos
self.title_item.setVisible(self.show_title)
self.title_item.setRotation(-self.graph_line.angle())
c = self.title_item.mapToParent(self.title_item.boundingRect().center())
tl = self.title_item.mapToParent(self.title_item.boundingRect().topLeft())
self.title_item.setPos(title_pos - c + tl)
## Arrows
if not zoom_only:
if self.start_arrow_item:
self.scene().removeItem(self.start_arrow_item)
self.start_arrow_item = None
if self.end_arrow_item:
self.scene().removeItem(self.end_arrow_item)
self.end_arrow_item = None
if self.arrows & AxisStart:
if not zoom_only or not self.start_arrow_item:
self.start_arrow_item = QGraphicsPathItem(self.arrow_path, self)
self.start_arrow_item.setPos(self.graph_line.p1())
self.start_arrow_item.setRotation(-self.graph_line.angle() + 180)
self.start_arrow_item.setBrush(line_color)
self.start_arrow_item.setPen(line_color)
if self.arrows & AxisEnd:
if not zoom_only or not self.end_arrow_item:
self.end_arrow_item = QGraphicsPathItem(self.arrow_path, self)
self.end_arrow_item.setPos(self.graph_line.p2())
self.end_arrow_item.setRotation(-self.graph_line.angle())
self.end_arrow_item.setBrush(line_color)
self.end_arrow_item.setPen(line_color)
## Labels
n = len(self._ticks)
resize_plot_item_list(self.label_items, n, QGraphicsTextItem, self)
resize_plot_item_list(self.label_bg_items, n, QGraphicsRectItem, self)
resize_plot_item_list(self.tick_items, n, QGraphicsLineItem, self)
test_rect = QRectF(self.graph_line.p1(), self.graph_line.p2()).normalized()
test_rect.adjust(-1, -1, 1, 1)
n_v = self.graph_line.normalVector().unitVector()
if self.title_above:
n_p = n_v.p2() - n_v.p1()
else:
n_p = n_v.p1() - n_v.p2()
l_v = self.graph_line.unitVector()
l_p = l_v.p2() - l_v.p1()
for i in range(n):
pos, text, size, step = self._ticks[i]
hs = 0.5 * step
tick_pos = self.map_to_graph(pos)
if not test_rect.contains(tick_pos):
self.tick_items[i].setVisible(False)
self.label_items[i].setVisible(False)
continue
item = self.label_items[i]
item.setVisible(True)
if not zoom_only:
if self.id in XAxes or getattr(self, 'is_horizontal', False):
item.setHtml('<center>' + Qt.escape(text.strip()) + '</center>')
else:
item.setHtml(Qt.escape(text.strip()))
item.setTextWidth(-1)
text_angle = 0
if dense_text:
w = min(item.boundingRect().width(), self.max_text_width)
item.setTextWidth(w)
if self.title_above:
label_pos = tick_pos + n_p * (w + self.text_margin) + l_p * item.boundingRect().height() / 2
else:
label_pos = tick_pos + n_p * self.text_margin + l_p * item.boundingRect().height() / 2
text_angle = -90 if self.title_above else 90
else:
w = min(item.boundingRect().width(),
QLineF(self.map_to_graph(pos - hs), self.map_to_graph(pos + hs)).length())
label_pos = tick_pos + n_p * self.text_margin + l_p * item.boundingRect().height() / 2
item.setTextWidth(w)
if not self.always_horizontal_text:
if self.title_above:
item.setRotation(-self.graph_line.angle() - text_angle)
else:
item.setRotation(self.graph_line.angle() - text_angle)
item.setPos(label_pos)
item.setDefaultTextColor(text_color)
self.label_bg_items[i].setRect(item.boundingRect())
self.label_bg_items[i].setPen(QPen(Qt.NoPen))
self.label_bg_items[i].setBrush(self.plot.color(OWPalette.Canvas))
item = self.tick_items[i]
item.setVisible(True)
tick_line = QLineF(v)
tick_line.translate(-tick_line.p1())
tick_line.setLength(size)
if self.title_above:
tick_line.setAngle(tick_line.angle() + 180)
item.setLine(tick_line)
item.setPen(line_color)
item.setPos(self.map_to_graph(pos))
@staticmethod
def make_title(label, unit=None):
lab = '<i>' + label + '</i>'
if unit:
lab = lab + ' [' + unit + ']'
return lab
def set_line(self, line):
self.graph_line = line
self.update()
def set_title(self, title):
self.title = title
self.update()
def set_show_title(self, b):
self.show_title = b
self.update()
def set_labels(self, labels, values):
self.labels = labels
self.values = values
self.graph_line = None
self.auto_scale = False
self.update_ticks()
self.update_graph()
def set_scale(self, min, max, step_size):
self.scale = (min, max, step_size)
self.graph_line = None
self.auto_scale = False
self.update_ticks()
self.update_graph()
def set_tick_length(self, minor, medium, major):
self.tick_length = (minor, medium, major)
self.update()
def map_to_graph(self, x):
min, max = self.plot.bounds_for_axis(self.id)
if min == max:
return QPointF()
line_point = self.graph_line.pointAt((x - min) / (max - min))
end_point = line_point * self.zoom_transform
return self.projection(end_point, self.graph_line)
@staticmethod
def projection(point, line):
norm = line.normalVector()
norm.translate(point - norm.p1())
p = QPointF()
type = line.intersect(norm, p)
return p
def continuous_labels(self):
min, max, step = self.scale
magnitude = log10(abs(max - min))
def paint(self, painter, option, widget):
pass
def boundingRect(self):
return QRectF()
def ticks(self):
if not self._ticks:
self.update_ticks()
return self._ticks
def bounds(self):
if self._bounds:
return self._bounds
if self.labels:
return -0.2, len(self.labels) - 0.8
elif self.scale:
min, max, _step = self.scale
return min, max
elif self.auto_range:
return self.auto_range
else:
return 0, 1
def set_bounds(self, value):
self._bounds = value
def should_be_expanded(self):
self.update_ticks()
return self.id in YAxes or self.always_horizontal_text or sum(
len(t[1]) for t in self._ticks) * 12 > self.plot.width()