Add an outline to the canvas (fix #299)

related to #184

debian/changelog

@@ -3,6 +3,7 @@ drawing (0.8.2) unstable; urgency=low
   * refactoring of the optionsbars (bottom panes) of the transform tools
   * add a "lock line direction" option to the line tool (#369)
   * fix shift+f10 action when using a selection tool on mobile
+  * add an outline to the canvas (#299, 184)
   * lock image proportions by default when scaling with the numerical inputs
   * update several translations
 

src/image.py

@@ -21,6 +21,7 @@
 from .selection_manager import DrSelectionManager
 from .properties import DrPropertiesDialog
 from .utilities import InvalidFileFormatException
+from .utilities_overlay import utilities_generic_canvas_outline
 
 class DrMotionBehavior():
 	_LIMIT = 10
@@ -380,7 +381,11 @@ def on_draw(self, area, cairo_context):
 		cairo_context.paint()
 
 		# What the tool is painting
-		self.active_tool().on_draw(area, cairo_context)
+		self.active_tool().on_draw_above(area, cairo_context)
+
+		# Limit of the canvas (for readability)
+		utilities_generic_canvas_outline(cairo_context, self.get_pixbuf_width(), \
+		                              self.get_pixbuf_height(), self.zoom_level)
 
 	def on_press_on_area(self, area, event):
 		"""Signal callback. Executed when a mouse button is pressed on

src/tools/abstract_tool.py

@@ -281,11 +281,8 @@ def on_unclicked_motion_on_area(self, event, surface):
 	def on_release_on_area(self, event, surface, event_x, event_y):
 		pass
 
-	def on_draw(self, area, cairo_context):
-		if not self.accept_selection:
-			return
-		if not self.selection_is_active():
-			return
+	def on_draw_above(self, area, cairo_context):
+		pass
 
 	############################################################################
 ################################################################################

src/tools/selection_tools/abstract_select.py

@@ -157,7 +157,7 @@ def on_release_on_area(self, event, surface, event_x, event_y):
 		elif self.behavior == 'drag':
 			self._apply_drag_to(event_x, event_y)
 
-	def on_draw(self, area, ccontext):
+	def on_draw_above(self, area, ccontext):
 		if not self.selection_is_active():
 			return
 		ldx = self.local_dx

src/tools/transform_tools/abstract_transform_tool.py

@@ -135,7 +135,7 @@ def get_handle_cursor_name(self, event_x, event_y):
 			cursor_name = cursor_name + '-resize'
 		return cursor_name
 
-	def on_draw(self, area, cairo_context):
+	def on_draw_above(self, area, cairo_context):
 		pass
 
 	def get_deformed_surface(self, source_surface, coefs):

src/tools/transform_tools/tool_crop.py

@@ -177,7 +177,7 @@ def on_release_on_area(self, event, surface, event_x, event_y):
 
 	############################################################################
 
-	def on_draw(self, area, cairo_context):
+	def on_draw_above(self, area, cairo_context):
 		if self.apply_to_selection:
 			x1 = int(self._x)
 			y1 = int(self._y)

src/tools/transform_tools/tool_scale.py

@@ -174,7 +174,7 @@ def on_release_on_area(self, event, surface, event_x, event_y):
 
 	############################################################################
 
-	def on_draw(self, area, cairo_context):
+	def on_draw_above(self, area, cairo_context):
 		if self.apply_to_selection:
 			x1 = int(self._x)
 			y1 = int(self._y)

src/tools/utilities_overlay.py

@@ -37,6 +37,9 @@ def utilities_show_overlay_on_context(ccontext, cpath, is_dashed, thickness=1):
 	ccontext.set_source_rgba(0.5, 0.5, 0.5, 0.5)
 	ccontext.stroke()
 
+################################################################################
+# Transform tools overlay ######################################################
+
 def utilities_show_handles_on_context(cairo_context, x1, x2, y1, y2, thickness=1):
 	"""Request the drawing of handles for a rectangle pixbuf having the provided
 	coords. Handles are only decorative objects drawn on the surface to help the
@@ -109,3 +112,21 @@ def _draw_arc_handle(cairo_context, x, y, rayon, orientation):
 	cairo_context.stroke()
 
 ################################################################################
+# Canvas generic ouline ########################################################
+
+def utilities_generic_canvas_outline(cairo_context, w, h, zoom_level):
+	cairo_context.set_source_rgba(0.0, 0.0, 0.0, 1.0)
+	cairo_context.set_dash([])
+	size = max(1, int(1 / zoom_level))
+	cairo_context.set_line_width(size)
+	cairo_context.move_to(w + size, 0)
+	cairo_context.rel_line_to(0, h + size)
+	cairo_context.line_to(0, h + size)
+	cairo_context.stroke_preserve()
+
+	cairo_context.set_source_rgba(1.0, 1.0, 1.0, 1.0)
+	cairo_context.set_dash([2 * size, 2 * size])
+	cairo_context.stroke()
+
+################################################################################
+