Make `contains?` inclusive (#137)

If point is over the visual area, it's true. Also add default rectangle implementation to `renderable.rb`.

11 files changed, 80 insertions, 86 deletions

diff --git a/lib/ruby2d/image.rb b/lib/ruby2d/image.rb
index 0516f4f..236df19 100644
--- a/lib/ruby2d/image.rb
+++ b/lib/ruby2d/image.rb
@@ -27,9 +27,5 @@ module Ruby2D
       @color = Color.new(c)
     end
 
-    def contains?(x, y)
-      @x < x and @x + @width > x and @y < y and @y + @height > y
-    end
-
   end
 end
diff --git a/lib/ruby2d/line.rb b/lib/ruby2d/line.rb
index e817acb..8beb8ff 100644
--- a/lib/ruby2d/line.rb
+++ b/lib/ruby2d/line.rb
@@ -32,9 +32,9 @@ module Ruby2D
     # the width. For reference:
     #   https://en.wikipedia.org/wiki/Distance_from_a_point_to_a_line
     def contains?(x, y)
-      points_distance(x1, y1, x, y) < length and
-      points_distance(x2, y2, x, y) < length and
-      (((@y2 - @y1) * x - (@x2 - @x1) * y + @x2 * @y1 - @y2 * @x1).abs / length) < 0.5 * @width
+      points_distance(x1, y1, x, y) <= length &&
+      points_distance(x2, y2, x, y) <= length &&
+      (((@y2 - @y1) * x - (@x2 - @x1) * y + @x2 * @y1 - @y2 * @x1).abs / length) <= 0.5 * @width
     end
 
     private
diff --git a/lib/ruby2d/rectangle.rb b/lib/ruby2d/rectangle.rb
index 43b0db5..07ee19b 100644
--- a/lib/ruby2d/rectangle.rb
+++ b/lib/ruby2d/rectangle.rb
@@ -40,10 +40,6 @@ module Ruby2D
       update_coords(@x, @y, @width, h)
     end
 
-    def contains?(x, y)
-      @x < x and @x + @width > x and @y < y and @y + @height > y
-    end
-
     private
 
     def update_coords(x, y, w, h)
diff --git a/lib/ruby2d/renderable.rb b/lib/ruby2d/renderable.rb
index 0e5da50..2599bc4 100644
--- a/lib/ruby2d/renderable.rb
+++ b/lib/ruby2d/renderable.rb
@@ -42,9 +42,9 @@ module Ruby2D
     def colour; self.color end
     def colour=(c); self.color = c end
 
-    # Add a contains method stub
+    # Check if given point is within a rectangle, by default (unless overridden)
     def contains?(x, y)
-      raise Error, "\`#contains?\` not implemented for this class yet"
+      x > @x && x < (@x + @width) && y > @y && y < (@y + @height)
     end
 
   end
diff --git a/lib/ruby2d/text.rb b/lib/ruby2d/text.rb
index 796cdb6..ea9a2a9 100644
--- a/lib/ruby2d/text.rb
+++ b/lib/ruby2d/text.rb
@@ -32,9 +32,5 @@ module Ruby2D
       @color = Color.new(c)
     end
 
-    def contains?(x, y)
-      @x < x and @x + @width > x and @y < y and @y + @height > y
-    end
-
   end
 end
diff --git a/test/image_spec.rb b/test/image_spec.rb
index e2ef37e..7d4f96d 100644
--- a/test/image_spec.rb
+++ b/test/image_spec.rb
@@ -8,19 +8,4 @@ RSpec.describe Ruby2D::Image do
     end
   end
 
-  describe "#contains?" do
-    it "returns true if point is inside the image" do
-      image = Image.new("test/media/image.bmp")
-      expect(image.contains?(50, 50)).to be true
-    end
-
-    it "returns true if point is outside the image" do
-      image = Image.new("test/media/image.bmp")
-      expect(image.contains?(-50, 50)).to be false
-      expect(image.contains?(50, -50)).to be false
-      expect(image.contains?(50, 150)).to be false
-      expect(image.contains?(150, 50)).to be false
-    end
-  end
-
 end
diff --git a/test/line_spec.rb b/test/line_spec.rb
index ac6d005..2129073 100644
--- a/test/line_spec.rb
+++ b/test/line_spec.rb
@@ -3,15 +3,16 @@ require 'ruby2d'
 RSpec.describe Ruby2D::Line do
 
   describe "#contains?" do
+    line = Line.new(x1: 0, y1: 0, x2: 100, y2: 100)
+
     it "returns true if point is inside the line" do
-      line = Line.new(x1: 0, y1: 0, x2: 100, y2: 100)
-      expect(line.contains?(25, 25)).to be true
+      expect(line.contains?(  0,   1)).to be true
+      expect(line.contains?(100, 100)).to be true
     end
 
     it "returns false if point is outside the line" do
-      line = Line.new(x1: 0, y1: 0, x2: 100, y2: 100)
-      expect(line.contains?(0, 10)).to be false
-      expect(line.contains?(10, 0)).to be false
+      expect(line.contains?(  0, 2)).to be false
+      expect(line.contains?(101, 0)).to be false
     end
   end
 
diff --git a/test/quad_spec.rb b/test/quad_spec.rb
index 1819fc0..8cace25 100644
--- a/test/quad_spec.rb
+++ b/test/quad_spec.rb
@@ -53,27 +53,21 @@ RSpec.describe Ruby2D::Quad do
   end
 
   describe "#contains?" do
+    quad = Quad.new(
+      x1: -25, y1:   0,
+      x2:   0, y2: -25,
+      x3:  25, y3:   0,
+      x4:   0, y4:  25
+    )
+
     it "returns true if point is inside the quad" do
-      quad = Quad.new(
-        x1: -25, y1:   0,
-        x2:   0, y2: -25,
-        x3:  25, y3:   0,
-        x4:   0, y4:  25
-      )
-      expect(quad.contains?(0, 0)).to be true
+      expect(quad.contains?(0 ,  0)).to be true
+      expect(quad.contains?(25,  0)).to be true
     end
 
-    it "returns true if point is outside the quad" do
-      quad = Quad.new(
-        x1: -25, y1:   0,
-        x2:   0, y2: -25,
-        x3:  25, y3:   0,
-        x4:   0, y4:  25
-      )
-      expect(quad.contains?( 20,  20)).to be false
-      expect(quad.contains?(-20,  20)).to be false
-      expect(quad.contains?( 20, -20)).to be false
-      expect(quad.contains?(-20, -20)).to be false
+    it "returns false if point is outside the quad" do
+      expect(quad.contains?(-26,  0)).to be false
+      expect(quad.contains?(  0, 26)).to be false
     end
   end
 
diff --git a/test/rectangle_spec.rb b/test/rectangle_spec.rb
deleted file mode 100644
index bbf1616..0000000
--- a/test/rectangle_spec.rb
+++ /dev/null
@@ -1,20 +0,0 @@
-require 'ruby2d'
-
-RSpec.describe Ruby2D::Rectangle do
-
-  describe "#contains?" do
-    it "returns true if point is inside the rectangle" do
-      rectangle = Rectangle.new(x: 0, y: 0, width: 50, height: 50)
-      expect(rectangle.contains?(25, 25)).to be true
-    end
-
-    it "returns true if point is outside the rectangle" do
-      rectangle = Rectangle.new(x: 0, y: 0, width: 50, height: 50)
-      expect(rectangle.contains?(-25,  25)).to be false
-      expect(rectangle.contains?( 25, -25)).to be false
-      expect(rectangle.contains?( 25,  50)).to be false
-      expect(rectangle.contains?( 50,  25)).to be false
-    end
-  end
-
-end
diff --git a/test/renderable_spec.rb b/test/renderable_spec.rb
index 56ee521..1352d5b 100644
--- a/test/renderable_spec.rb
+++ b/test/renderable_spec.rb
@@ -63,4 +63,53 @@ RSpec.describe Ruby2D::Renderable do
     expect(quad.a).to eq(0.6)
   end
 
+  describe "#contains?" do
+    square = Square.new(x: 1, y: 1, size: 2)
+
+    # Grid looks like this, 2x2 square at point (1, 1):
+    #
+    #   0  1  2  3  4
+    # 0 +--+--+--+--+
+    #   |  |  |  |  |
+    # 1 +--+--+--+--+
+    #   |  |XX|XX|  |
+    # 2 +--+--+--+--+
+    #   |  |XX|XX|  |
+    # 3 +--+--+--+--+
+    #   |  |  |  |  |
+    # 4 +--+--+--+--+
+
+    it "returns true if point is inside the rectangle" do
+      expect(square.contains?(1, 1)).to be true
+      expect(square.contains?(2, 1)).to be true
+      expect(square.contains?(3, 1)).to be true
+      expect(square.contains?(1, 2)).to be true
+      expect(square.contains?(2, 2)).to be true
+      expect(square.contains?(3, 2)).to be true
+      expect(square.contains?(1, 3)).to be true
+      expect(square.contains?(2, 3)).to be true
+      expect(square.contains?(3, 3)).to be true
+    end
+
+    it "returns false if point is outside the rectangle" do
+      # Clockwise around the square
+      expect(square.contains?(0, 0)).to be false
+      expect(square.contains?(1, 0)).to be false
+      expect(square.contains?(2, 0)).to be false
+      expect(square.contains?(3, 0)).to be false
+      expect(square.contains?(4, 0)).to be false
+      expect(square.contains?(4, 1)).to be false
+      expect(square.contains?(4, 2)).to be false
+      expect(square.contains?(4, 3)).to be false
+      expect(square.contains?(4, 4)).to be false
+      expect(square.contains?(3, 4)).to be false
+      expect(square.contains?(2, 4)).to be false
+      expect(square.contains?(1, 4)).to be false
+      expect(square.contains?(0, 4)).to be false
+      expect(square.contains?(0, 3)).to be false
+      expect(square.contains?(0, 2)).to be false
+      expect(square.contains?(0, 1)).to be false
+    end
+  end
+
 end
diff --git a/test/triangle_spec.rb b/test/triangle_spec.rb
index 1f9dc5d..2600d6f 100644
--- a/test/triangle_spec.rb
+++ b/test/triangle_spec.rb
@@ -52,24 +52,21 @@ RSpec.describe Ruby2D::Triangle do
   end
 
   describe "#contains?" do
+    triangle = Triangle.new(
+      x1:   0, y1:   0,
+      x2:   0, y2: 100,
+      x3: 100, y3:   0
+    )
+
     it "returns true if point is inside the triangle" do
-      triangle = Triangle.new(
-        x1:   0, y1:   0,
-        x2:   0, y2: 100,
-        x3: 100, y3:   0
-      )
+      expect(triangle.contains?( 0,  0)).to be true
       expect(triangle.contains?(25, 25)).to be true
     end
 
     it "returns false if point is outside the triangle" do
-      triangle = Triangle.new(
-        x1:   0, y1:   0,
-        x2:   0, y2: 100,
-        x3: 100, y3:   0
-      )
       expect(triangle.contains?( 25, -25)).to be false
       expect(triangle.contains?(-25,  25)).to be false
-      expect(triangle.contains?(100, 100)).to be false
+      expect(triangle.contains?(100,   1)).to be false
     end
   end