Start of the icon editor

src/bedit_gui/views/icon_graphics_scene.py

@@ -0,0 +1,123 @@
+from __future__ import annotations
+
+from typing import Protocol
+
+from PySide6.QtCore import QObject, QPointF, QRectF, Qt, Signal
+from PySide6.QtGui import QBrush, QColor, QPainterPath, QPen
+from PySide6.QtWidgets import QGraphicsPathItem, QGraphicsRectItem, QGraphicsScene, QGraphicsSceneMouseEvent
+
+from bedit_gui.models import Icon, LineType, Rectangle, Shape
+
+
+class ShapeCreationTool(Protocol):
+    def begin(self, position: QPointF) -> None: ...
+    def update(self, position: QPointF) -> None: ...
+    def finish(self, position: QPointF) -> Shape | None: ...
+    def cancel(self) -> None: ...
+
+
+class RectangleCreationTool:
+    def __init__(self, scene: QGraphicsScene, layer: int) -> None:
+        self.scene = scene
+        self.layer = layer
+        self.start: QPointF | None = None
+        self.preview: QGraphicsRectItem | None = None
+
+    def begin(self, position: QPointF) -> None:
+        self.start = position
+        self.preview = self.scene.addRect(QRectF(position, position), QPen(Qt.PenStyle.DashLine))
+
+    def update(self, position: QPointF) -> None:
+        if self.preview is not None and self.start is not None:
+            self.preview.setRect(QRectF(self.start, position).normalized())
+
+    def finish(self, position: QPointF) -> Rectangle | None:
+        if self.start is None:
+            return None
+        rect = QRectF(self.start, position).normalized()
+        self.cancel()
+        if rect.width() < 1 or rect.height() < 1:
+            return None
+        return Rectangle(layer=self.layer, pos=(round(rect.x()), round(rect.y())), width=rect.width(), height=rect.height())
+
+    def cancel(self) -> None:
+        if self.preview is not None:
+            self.scene.removeItem(self.preview)
+            self.preview = None
+        self.start = None
+
+
+class IconGraphicsScene(QGraphicsScene):
+    shape_created = Signal(object)
+    tool_active_changed = Signal(bool)
+
+    def __init__(self, parent: QObject | None = None) -> None:
+        super().__init__(parent)
+        self._tool: ShapeCreationTool | None = None
+        self.setSceneRect(-100, -100, 200, 200)
+
+    def set_icon(self, icon: Icon) -> None:
+        self.cancel_creation_tool()
+        self.clear()
+        for shape in sorted(icon.shapes.values(), key=lambda item: item.layer):
+            self._add_shape_item(shape)
+
+    def set_creation_tool(self, tool: ShapeCreationTool) -> None:
+        self.cancel_creation_tool()
+        self._tool = tool
+        self.tool_active_changed.emit(True)
+
+    def cancel_creation_tool(self) -> None:
+        if self._tool is None:
+            return
+        self._tool.cancel()
+        self._tool = None
+        self.tool_active_changed.emit(False)
+
+    def has_creation_tool(self) -> bool:
+        return self._tool is not None
+
+    def mousePressEvent(self, event: QGraphicsSceneMouseEvent) -> None:
+        if self._tool is not None and event.button() == Qt.MouseButton.LeftButton:
+            self._tool.begin(event.scenePos())
+            event.accept()
+            return
+        super().mousePressEvent(event)
+
+    def mouseMoveEvent(self, event: QGraphicsSceneMouseEvent) -> None:
+        if self._tool is not None and event.buttons() & Qt.MouseButton.LeftButton:
+            self._tool.update(event.scenePos())
+            event.accept()
+            return
+        super().mouseMoveEvent(event)
+
+    def mouseReleaseEvent(self, event: QGraphicsSceneMouseEvent) -> None:
+        if self._tool is not None and event.button() == Qt.MouseButton.LeftButton:
+            tool = self._tool
+            shape = tool.finish(event.scenePos())
+            self._tool = None
+            self.tool_active_changed.emit(False)
+            if shape is not None:
+                self.shape_created.emit(shape)
+            event.accept()
+            return
+        super().mouseReleaseEvent(event)
+
+    def _add_shape_item(self, shape: Shape) -> None:
+        if not isinstance(shape, Rectangle):
+            return
+        rect = QRectF(shape.pos[0], shape.pos[1], shape.width, shape.height)
+        path = QPainterPath()
+        path.addRoundedRect(rect, shape.corner_radius, shape.corner_radius)
+        item = QGraphicsPathItem(path)
+        item.setPen(self._pen(shape))
+        item.setBrush(QBrush(QColor(shape.fill_color)))
+        item.setZValue(shape.layer)
+        self.addItem(item)
+
+    @staticmethod
+    def _pen(shape: Rectangle) -> QPen:
+        styles = {LineType.SOLID: Qt.PenStyle.SolidLine, LineType.DASHED: Qt.PenStyle.DashLine, LineType.DOTTED: Qt.PenStyle.DotLine, LineType.DASH_DOT: Qt.PenStyle.DashDotLine}
+        if shape.line_type is LineType.NONE:
+            return QPen(Qt.PenStyle.NoPen)
+        return QPen(QColor(shape.line_color), shape.line_thickness, styles[shape.line_type])