From bba00487cb86631fc714ae635f882db017471131 Mon Sep 17 00:00:00 2001
From: Samuel Tallet <samuel.tallet@gmail.com>
Date: Mon, 25 Nov 2019 02:36:46 +0100
Subject: [PATCH] Handle onLightErased event.

---
 source/pbr/entity_observer.rb | 53 +++++++++++++++++++++++++++++++++++
 source/pbr/light.rb           |  5 ++++
 source/pbr/load.rb            |  3 ++
 source/pbr/material_editor.rb |  4 +--
 source/pbr/menu.rb            |  2 +-
 source/pbr/model_observer.rb  |  7 -----
 source/pbr/toolbar.rb         |  2 +-
 source/pbr/viewport.rb        |  4 +--
 8 files changed, 67 insertions(+), 13 deletions(-)
 create mode 100644 source/pbr/entity_observer.rb

diff --git a/source/pbr/entity_observer.rb b/source/pbr/entity_observer.rb
new file mode 100644
index 0000000..f4c7df5
--- /dev/null
+++ b/source/pbr/entity_observer.rb
@@ -0,0 +1,53 @@
+# Physically-Based Rendering extension for SketchUp 2017 or newer.
+# Copyright: © 2019 Samuel Tallet <samuel.tallet arobase gmail.com>
+# 
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3.0 of the License, or
+# (at your option) any later version.
+# 
+# If you release a modified version of this program TO THE PUBLIC,
+# the GPL requires you to MAKE THE MODIFIED SOURCE CODE AVAILABLE
+# to the program's users, UNDER THE GPL.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+# General Public License for more details.
+# 
+# Get a copy of the GPL here: https://www.gnu.org/licenses/gpl.html
+
+raise 'The PBR plugin requires at least Ruby 2.2.0 or SketchUp 2017.'\
+  unless RUBY_VERSION.to_f >= 2.2 # SketchUp 2017 includes Ruby 2.2.4.
+
+require 'sketchup'
+require 'pbr/light'
+require 'pbr/viewport'
+
+# PBR plugin namespace.
+module PBR
+
+  # Observes SketchUp entity events and reacts.
+  class EntityObserver < Sketchup::EntityObserver
+
+    # rubocop: disable Naming/MethodName
+
+    # When a SketchUp entity was erased.
+    def onEraseEntity(entity)
+
+      # If it was a PBR artificial light:
+      if SESSION[:lights_objects_ids].include?(entity.object_id.to_i)
+
+        Viewport.update_model_and_reopen
+
+        SESSION[:lights_objects_ids].delete(entity.object_id.to_i)
+
+      end
+
+    end
+
+    # rubocop: enable Naming/MethodName
+
+  end
+
+end
diff --git a/source/pbr/light.rb b/source/pbr/light.rb
index 32dbe37..7030850 100644
--- a/source/pbr/light.rb
+++ b/source/pbr/light.rb
@@ -22,6 +22,7 @@
 
 require 'sketchup'
 require 'pbr/shapes'
+require 'pbr/entity_observer'
 
 # PBR plugin namespace.
 module PBR
@@ -39,6 +40,10 @@ def initialize
 
       @light = Shapes.create_sphere('30cm', 10, 8, LAYER_NAME)
 
+      SESSION[:lights_objects_ids].push(@light.object_id.to_i)
+
+      @light.add_observer(EntityObserver.new)
+
     end
 
   end
diff --git a/source/pbr/load.rb b/source/pbr/load.rb
index 0eb28ea..235e4d6 100644
--- a/source/pbr/load.rb
+++ b/source/pbr/load.rb
@@ -42,6 +42,9 @@ module PBR
   # Storage for Chromium process ID.
   SESSION[:viewport_pid] = 0
 
+  # Memory of artificial lights IDs.
+  SESSION[:lights_objects_ids] = []
+
   # Plug PBR menu into SketchUp UI.
   Menu.new(
     UI.menu('Plugins') # parent_menu
diff --git a/source/pbr/material_editor.rb b/source/pbr/material_editor.rb
index c506dc1..ab0c019 100644
--- a/source/pbr/material_editor.rb
+++ b/source/pbr/material_editor.rb
@@ -22,6 +22,7 @@
 
 require 'sketchup'
 require 'pbr/html_dialogs'
+require 'pbr/viewport'
 
 # PBR plugin namespace.
 module PBR
@@ -159,8 +160,7 @@ def show
 
         @dialog.close
 
-        # Update and refresh PBR Viewport model.
-        Viewport.reopen if Viewport.update_model
+        Viewport.update_model_and_reopen
 
       end
 
diff --git a/source/pbr/menu.rb b/source/pbr/menu.rb
index 0f4b556..1eb101f 100644
--- a/source/pbr/menu.rb
+++ b/source/pbr/menu.rb
@@ -126,7 +126,7 @@ def initialize(parent_menu)
 
         return PBR.open_required_plugin_page unless PBR.required_plugin_exist?
 
-        Viewport.reopen_if_model_updated
+        Viewport.update_model_and_reopen
 
       end
 
diff --git a/source/pbr/model_observer.rb b/source/pbr/model_observer.rb
index 452615a..b21ba41 100644
--- a/source/pbr/model_observer.rb
+++ b/source/pbr/model_observer.rb
@@ -38,13 +38,6 @@ def onPreSaveModel(_model)
       
     end
 
-    # After a SketchUp model has been saved to disk.
-    def onPostSaveModel(_model)
-      
-      Viewport.open
-
-    end
-
     # rubocop: enable Naming/MethodName
 
   end
diff --git a/source/pbr/toolbar.rb b/source/pbr/toolbar.rb
index 815c1a3..a2b5c70 100644
--- a/source/pbr/toolbar.rb
+++ b/source/pbr/toolbar.rb
@@ -105,7 +105,7 @@ def initialize
 
         return PBR.open_required_plugin_page unless PBR.required_plugin_exist?
 
-        Viewport.reopen_if_model_updated
+        Viewport.update_model_and_reopen
 
       end
 
diff --git a/source/pbr/viewport.rb b/source/pbr/viewport.rb
index 083e182..e139391 100644
--- a/source/pbr/viewport.rb
+++ b/source/pbr/viewport.rb
@@ -145,10 +145,10 @@ def self.reopen
 
     end
 
-    # Reopens Viewport if model updated.
+    # Updates Viewport glTF model then reopens Viewport?
     #
     # @return [nil]
-    def self.reopen_if_model_updated
+    def self.update_model_and_reopen
 
       return Menu.propose_help(
         TRANSLATE['glTF export failed. Do you want help?']