1 files changed, 104 insertions, 0 deletions
diff --git a/assets/javascripts/rectangles/engine/clipper.js b/assets/javascripts/rectangles/engine/clipper.js
new file mode 100644
index 0000000..13fc378
--- /dev/null
+++ b/assets/javascripts/rectangles/engine/clipper.js
@@ -0,0 +1,104 @@
+
+var clipper = new function(){
+	var base = this
+
+	var rooms = base.rooms = []
+	var regions = base.regions = []
+
+	var modified = true
+
+	base.init = function(){
+		base.bind()
+		base.update()
+	}
+	
+	base.bind = function(){
+		map.ui.mouse.tube.on("up", function(){ base.update() })
+	}
+
+	base.update = function(){
+		clipper.solve_rects()
+		builder.tube("clipper:update")
+	}
+	
+	base.add_room = function(r){
+		rooms.push( new room({
+			id: base.rooms.length,
+			rect: r,
+		}) )
+	}
+	
+	base.solve_rects = function(){
+		if (base.rooms.length == 0) return;
+
+		for (var i = 0; i < base.rooms.length; i++) {
+			base.rooms[i].id = i
+			base.rooms[i].reset()
+		}
+
+		var rooms = sort_rooms_by_position( base.rooms )
+
+		var regions = []
+
+		var left, right
+		for (var i = 0; i < rooms.length; i++) {
+			left = rooms[i]
+			for (var j = i+1; j < rooms.length; j++) {
+				right = rooms[j]
+				if (left.rect.intersects(right.rect)) {
+					left.clipTo(right.rect)
+					right.clipTo(left.rect)
+				}
+				if (left.rect.x.b < right.rect.x.a) {
+					break
+				}
+			}
+		}
+		for (var i = 0; i < rooms.length; i++) {
+			rooms[i].regions = rooms[i].regions.filter(function(r){ return !!r })
+			regions = regions.concat(rooms[i].regions)
+		}
+
+		regions = sort_rects_by_area( regions )
+
+		var ty = new tree (regions[0].y.a, [regions[0]])
+		var tx = new tree (regions[0].x.a, ty)
+		var ttx, tty
+	
+		for (var i = 1; i < regions.length; i++) {
+			ttx = tx.add (regions[i].x.a, null)
+			if (ttx.data) {
+				tty = ttx.data.add (regions[i].y.a, null)
+				// duplicate polygon?
+				if (tty.data) {
+					tty.data.forEach(function(yy, ii){
+						if (yy.intersects(regions[i])) {
+							if (yy.area() > regions[i].area()) {
+								regions[i].dupe = true
+							}
+							else {
+								yy.dupe = true
+								tty.data[ii] = regions[i]
+							}
+						}
+					})
+				}
+				else {
+					tty.data = [regions[i]]
+				}
+			}
+			else {
+				ttx.data = new tree (regions[i].y.a, [regions[i]])
+			}
+		}
+
+		base.regions = sort_rects_by_position(regions)
+	}
+
+	// generate floor and ceiling for some regions
+	// generate walls from surviving regions
+	// generate ceiling-walls where ceiling has discontinuity
+
+	return base
+}
+