Can now render a canvas without the need for a View

examples/demo.py

@@ -17,7 +17,7 @@ import cairo
 import gi
 
 from examples.exampleitems import Box, Circle, FatLine, PortoBox, Text
-from gaphas import Canvas, GtkView, View, state
+from gaphas import Canvas, GtkView, state
 from gaphas.canvas import Context
 from gaphas.item import Line
 from gaphas.painter import (
@@ -112,13 +112,13 @@ def create_window(canvas, title, zoom=1.0):  # noqa too complex
     view = GtkView()
     view.painter = (
         PainterChain()
-        .append(FreeHandPainter(ItemPainter(view)))
+        .append(FreeHandPainter(ItemPainter(view.selection)))
         .append(HandlePainter(view))
         .append(FocusedItemPainter(view))
         .append(ToolPainter(view))
     )
     view.bounding_box_painter = BoundingBoxPainter(
-        FreeHandPainter(ItemPainter(view)), view.bounding_box_updater
+        FreeHandPainter(ItemPainter(view.selection)), view.bounding_box_updater
     )
     w = Gtk.Window()
     w.set_title(title)
@@ -236,25 +236,26 @@ def create_window(canvas, title, zoom=1.0):  # noqa too complex
     b = Gtk.Button.new_with_label("Write demo.png")
 
     def on_write_demo_png_clicked(button):
-        svgview = View(view.canvas)
+        painter = ItemPainter()
-        svgview.painter = ItemPainter(svgview)
 
         # Update bounding boxes with a temporary CairoContext
         # (used for stuff like calculating font metrics)
         tmpsurface = cairo.ImageSurface(cairo.FORMAT_ARGB32, 0, 0)
         tmpcr = cairo.Context(tmpsurface)
-        svgview.update_bounding_box(tmpcr)
+        bounding_box = (
+            BoundingBoxPainter(painter)
+            .paint(canvas.get_all_items(), tmpcr)
+            .bounding_box
+        )
         tmpcr.show_page()
         tmpsurface.flush()
 
-        w, h = svgview.bounding_box.width, svgview.bounding_box.height
+        surface = cairo.ImageSurface(
-        surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, int(w), int(h))
+            cairo.FORMAT_ARGB32, int(bounding_box.width), int(bounding_box.height)
+        )
         cr = cairo.Context(surface)
-        svgview.matrix.translate(-svgview.bounding_box.x, -svgview.bounding_box.y)
+        cr.translate(-bounding_box.x, -bounding_box.y)
-        cr.save()
+        painter.paint(items=view.canvas.get_all_items(), cairo=cr)
-        paint(svgview, cr)
-
-        cr.restore()
         cr.show_page()
         surface.write_to_png("demo.png")
 
@@ -264,22 +265,26 @@ def create_window(canvas, title, zoom=1.0):  # noqa too complex
     b = Gtk.Button.new_with_label("Write demo.svg")
 
     def on_write_demo_svg_clicked(button):
-        svgview = View(view.canvas)
+        painter = ItemPainter()
-        svgview.painter = ItemPainter(svgview)
 
         # Update bounding boxes with a temporaly CairoContext
         # (used for stuff like calculating font metrics)
         tmpsurface = cairo.ImageSurface(cairo.FORMAT_ARGB32, 0, 0)
         tmpcr = cairo.Context(tmpsurface)
-        svgview.update_bounding_box(tmpcr)
+        bounding_box = (
+            BoundingBoxPainter(painter)
+            .paint(canvas.get_all_items(), tmpcr)
+            .bounding_box
+        )
         tmpcr.show_page()
         tmpsurface.flush()
 
-        w, h = svgview.bounding_box.width, svgview.bounding_box.height
+        surface = cairo.SVGSurface(
-        surface = cairo.SVGSurface("demo.svg", w, h)
+            "demo.svg", int(bounding_box.width), int(bounding_box.height)
+        )
         cr = cairo.Context(surface)
-        svgview.matrix.translate(-svgview.bounding_box.x, -svgview.bounding_box.y)
+        cr.translate(-bounding_box.x, -bounding_box.y)
-        paint(svgview, cr)
+        painter.paint(items=view.canvas.get_all_items(), cairo=cr)
         cr.show_page()
         surface.flush()
         surface.finish()

gaphas/painter/__init__.py

@@ -12,7 +12,7 @@ def DefaultPainter(view) -> Painter:
     """Default painter, containing item, handle and tool painters."""
     return (
         PainterChain()
-        .append(ItemPainter(view))
+        .append(ItemPainter(view.selection))
         .append(HandlePainter(view))
         .append(FocusedItemPainter(view))
         .append(ToolPainter(view))

gaphas/painter/boundingboxpainter.py

@@ -98,10 +98,21 @@ class BoundingBoxPainter:
     def __init__(
         self,
         item_painter: ItemPainterType,
-        bounding_box_updater: Callable[[Item, Rectangle], None],
+        bounding_box_updater: Optional[Callable[[Item, Rectangle], None]] = None,
     ):
         self.item_painter = item_painter
-        self.bounding_box_updater = bounding_box_updater
+        if bounding_box_updater:
+            self.bounding_box_updater = bounding_box_updater
+        else:
+            self.bounding_box = Rectangle()
+
+            def default_bounding_box_updater(item, bounds):
+                if not self.bounding_box:
+                    self.bounding_box = Rectangle(*bounds)
+                else:
+                    self.bounding_box += bounds
+
+            self.bounding_box_updater = default_bounding_box_updater
 
     def paint_item(self, item, cairo):
         cairo = CairoBoundingBoxContext(cairo)
@@ -118,7 +129,8 @@ class BoundingBoxPainter:
         bounds.expand(1)
         self.bounding_box_updater(item, bounds)
 
-    def paint(self, items: Sequence[Item], cairo):
+    def paint(self, items: Sequence[Item], cairo) -> BoundingBoxPainter:
         """Draw the items."""
         for item in items:
             self.paint_item(item, cairo)
+        return self

gaphas/painter/itempainter.py

@@ -1,9 +1,10 @@
-from typing import Sequence
+from typing import Optional, Sequence
 
 from cairo import LINE_JOIN_ROUND
 
 from gaphas.canvas import Context
 from gaphas.item import Item
+from gaphas.view.selection import Selection
 
 # The tolerance for Cairo. Bigger values increase speed and reduce accuracy
 # (default: 0.1)
@@ -25,25 +26,26 @@ class ItemPainter:
 
     draw_all = False
 
-    def __init__(self, view=None):
+    def __init__(self, selection: Optional[Selection] = None):
-        assert view
+        self.selection = selection
-        self.view = view
 
     def paint_item(self, item, cairo):
-        view = self.view
         cairo.save()
         try:
             cairo.transform(item.matrix_i2c.to_cairo())
 
+            selection = self.selection
+            if not selection:
+                selection = Selection()
             item.draw(
                 DrawContext(
                     painter=self,
                     cairo=cairo,
                     _item=item,
-                    selected=(item in view.selection.selected_items),
+                    selected=(item in selection.selected_items),
-                    focused=(item is view.selection.focused_item),
+                    focused=(item is selection.focused_item),
-                    hovered=(item is view.selection.hovered_item),
+                    hovered=(item is selection.hovered_item),
-                    dropzone=(item is view.selection.dropzone_item),
+                    dropzone=(item is selection.dropzone_item),
                     draw_all=self.draw_all,
                 )
             )

gaphas/view/view.py

@@ -15,7 +15,7 @@ class View:
         self._matrix = Matrix()
         self._painter: Painter = DefaultPainter(self)
         self._bounding_box_painter: Painter = BoundingBoxPainter(
-            ItemPainter(self), self.bounding_box_updater
+            ItemPainter(self.selection), self.bounding_box_updater  # type: ignore[attr-defined]
         )
 
         self._qtree: Quadtree[Item, Tuple[float, float, float, float]] = Quadtree()

tests/test_segment.py

@@ -4,7 +4,7 @@ import pytest
 from gaphas.canvas import Canvas
 from gaphas.item import Item
 from gaphas.segment import HandleFinder, Line, Segment, SegmentHandleFinder
-from gaphas.view import View
+from gaphas.view import GtkView
 
 
 class SegmentFixture:
@@ -12,7 +12,7 @@ class SegmentFixture:
         self.canvas = Canvas()
         self.line = Line()
         self.canvas.add(self.line)
-        self.view = View(self.canvas)
+        self.view = GtkView(self.canvas)
         self.item = Item()
 
 

tests/test_view.py

@@ -6,7 +6,7 @@ from gi.repository import Gtk
 
 from gaphas.canvas import Canvas
 from gaphas.item import Element as Box
-from gaphas.view import GtkView, View
+from gaphas.view import GtkView
 
 
 class ViewFixture:
@@ -91,14 +91,6 @@ def test_item_removal(view_fixture):
 def test_view_registration(view_fixture):
     canvas = Canvas()
 
-    # Simple views do not register on the canvas
-
-    view = View(canvas)
-    assert len(canvas._registered_views) == 0
-
-    box = Box()
-    canvas.add(box)
-
     # GTK view does register for updates though
 
     view = GtkView(canvas)