1 files changed, 103 insertions, 0 deletions
diff --git a/reference_points.e b/reference_points.e
new file mode 100644
index 0000000..8059108
--- /dev/null
+++ b/reference_points.e
@@ -0,0 +1,103 @@
+class REFERENCE_POINTS
+
+insert PLATFORM
+	
+create {CALIBRATION}
+	make
+
+feature {}
+	make is
+		do
+			create x_device_points.with_capacity(10)
+			create y_device_points.with_capacity(10)
+			create x_display_points.with_capacity(10)
+			create y_display_points.with_capacity(10)
+		end
+
+feature {ANY}
+	add_point(x_device, y_device, x_display, y_display: INTEGER) is
+		do
+			x_device_points.add_last(x_device)
+			y_device_points.add_last(y_device)
+			x_display_points.add_last(x_display)
+			y_display_points.add_last(y_display)
+		ensure
+			count = old count + 1
+		end
+
+	count: INTEGER is
+		do
+			Result := x_device_points.count
+		end
+
+	find_best_pair_for(x, y: INTEGER) is
+			-- Find the two nearest points for (x, y) in device 
+			-- coordinates, trying as much as possible to get one point 
+			-- on each side.
+			--
+			-- Note: The result can be the same point twice
+		local
+			d1, d2, d_min, tmp: INTEGER_64
+			p1, p2: INTEGER
+			i1, i2: INTEGER
+			x1, y1, x2, y2: INTEGER
+		do
+			from
+				i1 := x_device_points.upper
+				d_min := Maximum_integer_64
+			until
+				i1 < x_device_points.lower
+			loop
+				x1 := x_device_points.item(i1)
+				d1 := x1 - x
+				d1 := d1 * d1
+				y1 := y_device_points.item(i1)
+				tmp := y1 - y
+				d1 := d1 + tmp * tmp
+				if d1 < d_min then
+					from
+						i2 := i1 - 1
+					until
+						i2 < x_device_points.lower
+					loop
+						x2 := x_device_points.item(i2)
+						y2 := y_device_points.item(i2)
+						if ((x1 < x) xor (x2 < x)) and then
+							((y1 < y) xor (y2 < y)) then
+							d2 := x2 - x
+							tmp := y2 - y
+							d2 := d2 * d2 + tmp * tmp + d1
+							if d2 < d_min then
+								d_min := d2
+								p1 := i1
+								p2 := i2
+							end
+						end
+						i2 := i2 - 1
+					end
+				end
+				i1 := i1 - 1
+			end
+			-- *** le cas où on ne peut pas trouver un point de chaque 
+			-- coté n'est pas géré
+			-- *** a la fin, il faudrait renseigner last_*
+		end
+
+	last_point1_x, last_point1_y: INTEGER
+			-- Answer point for `find_best_pair_for'
+
+	last_point2_x, last_point2_y: INTEGER
+			-- Answer point for `find_best_pair_for'
+	
+feature {}
+	x_device_points, y_device_points: FAST_ARRAY[INTEGER]
+
+	x_display_points, y_display_points: FAST_ARRAY[INTEGER]
+
+invariant
+	x_display_points.count = count
+	y_display_points.count = count
+	x_device_points.count = count
+	y_device_points.count = count
+	
+end