1 files changed, 11 insertions, 4 deletions
diff --git a/public/assets/test/intersect.html b/public/assets/test/intersect.html
index 5e16f2e..4e5b0bb 100644
--- a/public/assets/test/intersect.html
+++ b/public/assets/test/intersect.html
@@ -1,4 +1,5 @@
 <canvas id="canvas"></canvas>
+<div id="hud"></div>
 
 <script src="/assets/javascripts/util.js"></script>
 <script src="/assets/javascripts/vendor/tube.js"></script>
@@ -73,16 +74,21 @@ function draw () {
   
   var collinear = is_collinear( intersect, vec_b )
   var long_enough_to_intersect = 0 <= t && t <= 1
+  var msg
   
   if (long_enough_to_intersect && collinear) {
     ctx.fillStyle = "#f00"
+    msg = "through"
   }
   else if (collinear) {
     ctx.fillStyle = "#0f0"
+    msg = "to"
   }
   else {
     ctx.fillStyle = "#000"
+    msg = "off"
   }
+  hud.innerHTML = [intersect.exactString(), vec_b.exactString(), msg].join("<br>")
   
   drawPoint(intersect)
 }
@@ -105,19 +111,20 @@ function perp (va, vb) {
 }
 function is_collinear (p, vec) {
   var on_x, on_y
+  var pa = round(p.a), pb = round(p.b)
   
   if (vec.x.a < vec.y.a) {
-    on_x = vec.x.a <= p.a && p.a <= vec.y.a
+    on_x = vec.x.a <= pa && pa <= vec.y.a
   }
   else {
-    on_x = vec.x.a >= p.a && p.a >= vec.y.a
+    on_x = vec.x.a >= pa && pa >= vec.y.a
   }
   
   if (vec.x.b < vec.y.b) {
-    on_y = vec.x.b <= p.b && p.b <= vec.y.b
+    on_y = vec.x.b <= pb && pb <= vec.y.b
   }
   else {
-    on_y = vec.x.b >= p.b && p.b >= vec.y.b
+    on_y = vec.x.b >= pb && pb >= vec.y.b
   }
 
   return !! (on_x && on_y)