PaintTool: Undo/Redo should be working now.

Also fix missing pen-shape I suppose.

part of CURA-12543

plugins/PaintTool/PaintTool.py

@@ -41,9 +41,12 @@ class PaintTool(Tool):
         self._brush_size: int = 10
         self._brush_color: str = "A"
         self._brush_shape: str = "A"
-        self._brush_pen: Optional[QPen] = None
+        self._brush_pen: QPen = self._createBrushPen()
 
         self._mouse_held: bool = False
+        self._ctrl_held: bool = False
+        self._shift_held: bool = False
+
         self._last_text_coords: Optional[Tuple[int, int]] = None
 
     def _createBrushPen(self) -> QPen:
@@ -96,6 +99,20 @@ class PaintTool(Tool):
             self._brush_shape = brush_shape
             self._brush_pen = self._createBrushPen()
 
+    def undoStackAction(self, redo_instead: bool) -> bool:
+        paintview = Application.getInstance().getController().getActiveView()
+        if paintview is None or paintview.getPluginId() != "PaintTool":
+            return False
+        paintview = cast(PaintView, paintview)
+        if redo_instead:
+            paintview.redoStroke()
+        else:
+            paintview.undoStroke()
+        nodes = Selection.getAllSelectedObjects()
+        if len(nodes) > 0:
+            Application.getInstance().getController().getScene().sceneChanged.emit(nodes[0])
+        return True
+
     @staticmethod
     def _get_intersect_ratio_via_pt(a: numpy.ndarray, pt: numpy.ndarray, b: numpy.ndarray, c: numpy.ndarray) -> float:
         # compute the intersection of (param) A - pt with (param) B - (param) C
@@ -154,6 +171,10 @@ class PaintTool(Tool):
         super().event(event)
 
         controller = Application.getInstance().getController()
+        nodes = Selection.getAllSelectedObjects()
+        if len(nodes) <= 0:
+            return False
+        node = nodes[0]
 
         # Make sure the displayed values are updated if the bounding box of the selected mesh(es) changes
         if event.type == Event.ToolActivateEvent:
@@ -166,7 +187,27 @@ class PaintTool(Tool):
             controller.setActiveView("SolidView")
             return True
 
-        if event.type == Event.KeyPressEvent and cast(KeyEvent, event).key == KeyEvent.ShiftKey:
+        if event.type == Event.KeyPressEvent:
+            evt = cast(KeyEvent, event)
+            if evt.key == KeyEvent.ControlKey:
+                self._ctrl_held = True
+                return True
+            if evt.key == KeyEvent.ShiftKey:
+                self._shift_held = True
+                return True
+            return False
+
+        if event.type == Event.KeyReleaseEvent:
+            evt = cast(KeyEvent, event)
+            if evt.key == KeyEvent.ControlKey:
+                self._ctrl_held = False
+                return True
+            if evt.key == KeyEvent.ShiftKey:
+                self._shift_held = False
+                return True
+            if evt.key == Qt.Key.Key_L and self._ctrl_held:
+                # NOTE: Ctrl-L is used here instead of Ctrl-Z, as the latter is the application-wide one that takes precedence.
+                return self.undoStackAction(self._shift_held)
             return False
 
         if event.type == Event.MouseReleaseEvent and self._controller.getToolsEnabled():
@@ -201,10 +242,6 @@ class PaintTool(Tool):
             if not camera:
                 return False
 
-            node = Selection.getAllSelectedObjects()[0]
-            if node is None:
-                return False
-
             if node != self._node_cache:
                 if self._node_cache is not None:
                     self._node_cache.transformationChanged.disconnect(self._nodeTransformChanged)

plugins/PaintTool/PaintTool.qml

@@ -176,5 +176,40 @@ Item
                 }
             }
         }
+
+        RowLayout
+        {
+            UM.ToolbarButton
+            {
+                id: undoButton
+
+                text: catalog.i18nc("@action:button", "Undo Stroke")
+                toolItem: UM.ColorImage
+                {
+                    source: UM.Theme.getIcon("ArrowReset")
+                }
+                property bool needBorder: true
+
+                z: 2
+
+                onClicked: UM.Controller.triggerActionWithData("undoStackAction", false)
+            }
+
+            UM.ToolbarButton
+            {
+                id: redoButton
+
+                text: catalog.i18nc("@action:button", "Redo Stroke")
+                toolItem: UM.ColorImage
+                {
+                    source: UM.Theme.getIcon("ArrowDoubleCircleRight")
+                }
+                property bool needBorder: true
+
+                z: 2
+
+                onClicked: UM.Controller.triggerActionWithData("undoStackAction", true)
+            }
+        }
     }
 }

plugins/PaintTool/PaintView.py

@@ -2,9 +2,13 @@
 # Cura is released under the terms of the LGPLv3 or higher.
 
 import os
-from PyQt6.QtGui import QImage
+from typing import Optional, List, Tuple
+
+from PyQt6.QtGui import QImage, QColor, QPainter
 
 from UM.PluginRegistry import PluginRegistry
+from UM.View.GL.ShaderProgram import ShaderProgram
+from UM.View.GL.Texture import Texture
 from UM.View.View import View
 from UM.Scene.Selection import Selection
 from UM.View.GL.OpenGL import OpenGL
@@ -16,15 +20,23 @@ catalog = i18nCatalog("cura")
 class PaintView(View):
     """View for model-painting."""
 
+    UNDO_STACK_SIZE = 1024
+
     def __init__(self) -> None:
         super().__init__()
-        self._paint_shader = None
-        self._paint_texture = None
+        self._paint_shader: Optional[ShaderProgram] = None
+        self._paint_texture: Optional[Texture] = None
 
         # FIXME: When the texture UV-unwrapping is done, these two values will need to be set to a proper value (suggest 4096 for both).
         self._tex_width = 512
         self._tex_height = 512
 
+        self._stroke_undo_stack: List[Tuple[QImage, int, int]] = []
+        self._stroke_redo_stack: List[Tuple[QImage, int, int]] = []
+
+        self._force_opaque_mask = QImage(2, 2, QImage.Format.Format_Mono)
+        self._force_opaque_mask.fill(1)
+
     def _checkSetup(self):
         if not self._paint_shader:
             shader_filename = os.path.join(PluginRegistry.getInstance().getPluginPath("PaintTool"), "paint.shader")
@@ -33,8 +45,42 @@ class PaintView(View):
             self._paint_texture = OpenGL.getInstance().createTexture(self._tex_width, self._tex_height)
             self._paint_shader.setTexture(0, self._paint_texture)
 
+    def _forceOpaqueDeepCopy(self, image: QImage):
+        res = QImage(image.width(), image.height(), QImage.Format.Format_RGBA8888)
+        res.fill(QColor(255, 255, 255, 255))
+        painter = QPainter(res)
+        painter.setRenderHint(QPainter.RenderHint.Antialiasing, False)
+        painter.setCompositionMode(QPainter.CompositionMode.CompositionMode_SourceOver)
+        painter.drawImage(0, 0, image)
+        painter.end()
+        res.setAlphaChannel(self._force_opaque_mask.scaled(image.width(), image.height()))
+        return res
+
     def addStroke(self, stroke_image: QImage, start_x: int, start_y: int) -> None:
-        self._paint_texture.setSubImage(stroke_image, start_x, start_y)
+        self._stroke_redo_stack.clear()
+        if len(self._stroke_undo_stack) >= PaintView.UNDO_STACK_SIZE:
+            self._stroke_undo_stack.pop(0)
+        undo_image = self._forceOpaqueDeepCopy(self._paint_texture.setSubImage(stroke_image, start_x, start_y))
+        if undo_image is not None:
+            self._stroke_undo_stack.append((undo_image, start_x, start_y))
+
+    def _applyUndoStacksAction(self, from_stack: List[Tuple[QImage, int, int]], to_stack: List[Tuple[QImage, int, int]]) -> bool:
+        if len(from_stack) <= 0:
+            return False
+        from_image, x, y = from_stack.pop()
+        to_image = self._forceOpaqueDeepCopy(self._paint_texture.setSubImage(from_image, x, y))
+        if to_image is None:
+            return False
+        if len(to_stack) >= PaintView.UNDO_STACK_SIZE:
+            to_stack.pop(0)
+        to_stack.append((to_image, x, y))
+        return True
+
+    def undoStroke(self) -> bool:
+        return self._applyUndoStacksAction(self._stroke_undo_stack, self._stroke_redo_stack)
+
+    def redoStroke(self) -> bool:
+        return self._applyUndoStacksAction(self._stroke_redo_stack, self._stroke_undo_stack)
 
     def getUvTexDimensions(self):
         return self._tex_width, self._tex_height