Start of graph view

2026-08-15 17:18:51 +02:00
parent 961a173a17
commit 0c93338e39
4 changed files with 194 additions and 3 deletions
@@ -0,0 +1,83 @@
+from __future__ import annotations
+
+from PySide6.QtCore import QEvent, QObject, QRectF, Qt
+from PySide6.QtGui import QColor, QPainter, QPen, QWheelEvent
+from PySide6.QtWidgets import QGraphicsScene, QGraphicsView, QWidget
+
+from bedit_core.models import Component, GraphImplementation
+from bedit_gui.ui.generated.ui_graph_editor_widget import Ui_graphEditorWidget
+
+GRID_SPACING = 32
+SCENE_SIZE = 10000
+MIN_ZOOM = 0.2
+MAX_ZOOM = 4.0
+ZOOM_STEP = 1.15
+
+
+class GraphGraphicsScene(QGraphicsScene):
+    """Graph canvas with a lightweight dotted-line grid."""
+
+    def drawBackground(self, painter: QPainter, rect: QRectF) -> None:
+        painter.fillRect(rect, QColor("white"))
+        pen = QPen(QColor(205, 205, 205), 0, Qt.PenStyle.DotLine)
+        painter.setPen(pen)
+
+        left = int(rect.left()) - int(rect.left()) % GRID_SPACING
+        top = int(rect.top()) - int(rect.top()) % GRID_SPACING
+        x = left
+        while x <= rect.right():
+            painter.drawLine(x, rect.top(), x, rect.bottom())
+            x += GRID_SPACING
+        y = top
+        while y <= rect.bottom():
+            painter.drawLine(rect.left(), y, rect.right(), y)
+            y += GRID_SPACING
+
+
+class GraphEditorWidget(QWidget):
+    def __init__(self, parent: QWidget | None = None) -> None:
+        super().__init__(parent)
+
+        self.ui = Ui_graphEditorWidget()
+        self.ui.setupUi(self)
+        self._component: Component | None = None
+        self.scene = GraphGraphicsScene(self)
+        self.scene.setSceneRect(-SCENE_SIZE / 2, -SCENE_SIZE / 2, SCENE_SIZE, SCENE_SIZE)
+        self.ui.graphicsView.setScene(self.scene)
+        self.ui.graphicsView.setTransformationAnchor(QGraphicsView.ViewportAnchor.AnchorUnderMouse)
+        self.ui.graphicsView.viewport().installEventFilter(self)
+        self.ui.graphicsView.centerOn(0, 0)
+
+    def set_component(self, component: Component | None) -> None:
+        if component is not None and not isinstance(component.implementation, GraphImplementation):
+            raise TypeError("GraphEditorWidget only supports components with a graph implementation")
+        self._component = component
+
+    def component(self) -> Component | None:
+        return self._component
+
+    def eventFilter(self, watched: QObject, event: QEvent) -> bool:
+        if watched is self.ui.graphicsView.viewport() and event.type() == QEvent.Type.Wheel:
+            assert isinstance(event, QWheelEvent)
+            if event.modifiers() & Qt.KeyboardModifier.ControlModifier:
+                self._zoom(event)
+                return True
+            if event.modifiers() & Qt.KeyboardModifier.ShiftModifier:
+                self._scroll_horizontally(event)
+                return True
+        return super().eventFilter(watched, event)
+
+    def _zoom(self, event: QWheelEvent) -> None:
+        delta = event.angleDelta().y() or event.pixelDelta().y()
+        if not delta:
+            return
+        current_zoom = self.ui.graphicsView.transform().m11()
+        requested_zoom = current_zoom * ZOOM_STEP ** (delta / 120)
+        target_zoom = min(MAX_ZOOM, max(MIN_ZOOM, requested_zoom))
+        self.ui.graphicsView.scale(target_zoom / current_zoom, target_zoom / current_zoom)
+
+    def _scroll_horizontally(self, event: QWheelEvent) -> None:
+        scrollbar = self.ui.graphicsView.horizontalScrollBar()
+        pixel_delta = event.pixelDelta().y()
+        distance = pixel_delta if pixel_delta else event.angleDelta().y() / 120 * scrollbar.singleStep() * 3
+        scrollbar.setValue(scrollbar.value() - round(distance))