Properly structure HEX_BGs class

main.rb

@@ -60,38 +60,44 @@ def recalculate_hexagons
   puts "(#{$hex_points[3][0]},#{$hex_points[3][1]})".center(HEX_DEBUG_WIDTH)
   $hex_x_offset = $hex_width/2
   $hex_y_offset = $hex_tip + $hex_mid
-  $hex_bgs.clear
+  $hex_bgs.clear!
 end
 
 class HexEditXref_BgGrphStore
   def initialize
+    clear!
+  end
+  def clear!
     @hex_ids = Hash.new  #hexid => color
-    @hex_refs = Hash.new #color => [num_refs, hexids]
+    @hex_refs = Hash.new #color => hexids
     @hex_bgs = Hash.new  #color => bg
   end
   def register(hexid,color)
-    argb=color.argb
+    raise TypeError, ("color must be a Gosu::Color, not a '#{color.class}'"
+      ) unless color.is_a? Gosu::Color
+    argb = color.argb
+    return if (@hex_ids.has_key?(hexid) &&
+               @hex_ids[hexid] == argb)
     unregister hexid
     @hex_ids[hexid] = argb
     if @hex_refs.has_key? argb
-      @hex_refs[argb][0] += 1
-      unless @hex_refs[argb][1].include? hexid
-        @hex_refs[argb][1].append hexid
-      end
+      @hex_refs[argb].add(hexid)
+    else
+      @hex_refs[argb] = Set.new([hexid, ])
     end
     render argb
   end
   def unregister(hexid)
-    if @hex_ids.has_key? hexid
-      argb = @hex_ids[hexid]
-      @hex_ids.delete hexid
-    end
+    return unless @hex_ids.has_key? hexid
+    # ➣ If the key doesn't exist, assume
+    #   the call was made mistakenly.
+    # Note: may cause leaks later
+
+    argb = @hex_ids[hexid]
+    @hex_ids.delete hexid
     if @hex_refs.has_key? argb
-      if @hex_refs[argb][1].include? hexid
-        @hex_refs[argb][1].delete hexid
-        @hex_refs[argb][0] -= 1
-      end
-      if @hex_refs[argb][0] < 1
+      @hex_refs[argb].delete hexid
+      if @hex_refs[argb].size < 1
         @hex_refs.delete argb
       end
     end
@@ -101,6 +107,8 @@ class HexEditXref_BgGrphStore
     end
   end
   def [](color)
+    raise TypeError, ("color must be a Gosu::Color, not a '#{color.class}'"
+      ) unless color.is_a? Gosu::Color
     argb = color.argb
     raise RuntimeError.new(
         "Color #{argb} was requested from "+
@@ -109,9 +117,10 @@ class HexEditXref_BgGrphStore
       ) unless @hex_bgs.has_key? argb
     return @hex_bgs[argb]
   end
+  private
   def render(argb)
     color = Gosu::Color.new(argb)
-    @hex_bgs[argb] = [Gosu::record($hex_width, $hex_mid+($hex_tip*2)) {
+    @hex_bgs[argb] = Gosu::record($hex_width, $hex_mid+($hex_tip*2)) {
       # Double Quad Method (0145, 1234):
       Gosu::draw_quad( # 0145
         $hex_points[0][0], $hex_points[0][1], color, #0
@@ -127,8 +136,7 @@ class HexEditXref_BgGrphStore
         $hex_points[4][0], $hex_points[4][1], color, #4
         0
       )
-      },Time.now
-    ]
+      }
   end
 end
 
@@ -339,7 +347,7 @@ class HexagonTerminalWindow < Gosu::Window
   end
 end
 
-$hex_bgs = HexBgCache.new
+$hex_bgs = HexEditXref_BgGrphStore.new
 recalculate_hexagons
 window = HexagonTerminalWindow.new(800, 600, false)
 window.show