Frames in a Screen can now be offset by arbitrary values from point o…

…f origin

lib/remedy/frame.rb

@@ -62,11 +62,17 @@ def initialize name: self.object_id
       @nl = ?\n
     end
 
-    attr_accessor :vorigin, :horigin, :offset, :depth
+    attr_accessor :vorigin, :horigin, :depth
     attr_accessor :name, :size, :available_size
     attr_accessor :nl, :fill, :halign, :valign
     attr_accessor :contents, :arrangement
 
+    # Sets the offset from the origin point.
+    # @note Positive offsets always move the frame right and down,
+    #   so negative values are more useful when `horigin = :right` and/or `vorigin = :bottom`.
+    # @return [Remedy::Tuple] the vertical and horizontal offset to apply
+    attr_accessor :offset
+
     def to_a
       compile_contents
     end

lib/remedy/screen.rb

@@ -109,6 +109,9 @@ def populate_buffer
           raise "Unknown horigin:#{frame.horigin}"
         end
 
+        voffset += frame.offset.height
+        hoffset += frame.offset.width
+
         buffer[voffset,hoffset] = frame
       end
     end

spec/screen_spec.rb

@@ -128,4 +128,36 @@
       expect(actual).to eq expected
     end
   end
+
+  describe "offset frames" do
+    let(:new_size_override){ Tuple 5, 9 }
+
+    before do
+      frame.vorigin = :bottom
+      frame.horigin = :right
+      frame.halign  = :center
+      frame.valign  = :center
+      frame.offset = Tuple -1, -2
+      frame.size = Tuple(4, 0.5)
+      frame.fill = "."
+    end
+
+    it "moves the frame away from the point of origin" do
+
+      expected = [
+        "   foo.  ",
+        "   bar.  ",
+        "   baz.  ",
+        "   ....  ",
+        "         "
+      ].join ?\n
+
+      s.buffer.fill = " "
+      s.frames << frame
+      s.resized new_size_override, redraw: false
+      actual = s.to_s
+
+      expect(actual).to eq expected
+    end
+  end
 end