From c0fe6750cc0462adbc2165ac7f8c9cf1e0aea925 Mon Sep 17 00:00:00 2001
From: Jules Laplace <jules@okfoc.us>
Date: Thu, 30 Oct 2014 17:59:44 -0400
Subject: intersection test

---
 public/assets/test/intersect.html | 132 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 132 insertions(+)
 create mode 100644 public/assets/test/intersect.html

(limited to 'public/assets/test/intersect.html')

diff --git a/public/assets/test/intersect.html b/public/assets/test/intersect.html
new file mode 100644
index 0000000..3f6d110
--- /dev/null
+++ b/public/assets/test/intersect.html
@@ -0,0 +1,132 @@
+<canvas id="canvas"></canvas>
+
+<script src="/assets/javascripts/util.js"></script>
+<script src="/assets/javascripts/vendor/tube.js"></script>
+<script src="/assets/javascripts/rectangles/util/constants.js"></script>
+<script src="/assets/javascripts/rectangles/util/mouse.js"></script>
+<script src="/assets/javascripts/rectangles/models/vec2.js"></script>
+<script src="/assets/javascripts/rectangles/models/rect.js"></script>
+<script src="/assets/javascripts/vendor/canvasutilities.js"></script>
+<script>
+
+var ctx = canvas.getContext('2d')
+
+var w = canvas.width = 600
+var h = canvas.height = 400
+
+var vec_a = new Rect( 100, 120, 50, 100 )
+var vec_b = new Rect( 20, 200, 120, 120 )
+var vecs = [ vec_a, vec_b ]
+var points = [ vec_a.x, vec_a.y, vec_b.x, vec_b.y ]
+var r = 4
+
+var vec_c = new Rect()
+vec_c.x = vec_a.x
+vec_c.y = vec_b.x
+
+var intersect = new vec2 ()
+
+var dragging = false, dragging_a, dragging_b
+var delta = new vec2( 0, 0 )
+
+var mymouse = new mouse({
+  el: canvas,
+  down: function(e, cursor){
+    points.some(function(p){
+      if (-cursor.x.a > p.a - r && -cursor.x.a < p.a + r &&
+           cursor.y.a > p.b - r &&  cursor.y.a < p.b + r) {
+        dragging_a = p.a
+        dragging_b = p.b
+        dragging = p
+        return true
+      }
+    })
+  },
+  drag: function(e, cursor){
+    if (! dragging) return
+    delta = cursor.delta()
+    delta.a = - delta.a
+    dragging.a = dragging_a + delta.a
+    dragging.b = dragging_b + delta.b
+  },
+  up: function(e, cursor, new_cursor){
+    delta.zero()
+    dragging.dragging = false
+    dragging = false
+  },
+})
+
+function draw () {
+  ctx.fillStyle = "#fff"
+  ctx.fillRect(0,0,w,h)
+  
+  ctx.fillStyle = "#bbb"
+  points.forEach(drawPoint)
+  
+  drawLine(vec_a.x, vec_a.y, "#f00")
+  drawLine(vec_b.x, vec_b.y, "#00f")
+  drawLine(vec_a.x, vec_b.x, "#080")
+
+  var t = perp(vec_c, vec_b) / ( perp(vec_a, vec_b) || 0.0000001 )
+  intersect.a = vec_a.x.a + ( vec_a.y.a - vec_a.x.a ) * t
+  intersect.b = vec_a.x.b + ( vec_a.y.b - vec_a.x.b ) * t
+  
+  var collinear = is_collinear( intersect.b, vec_b )
+  var long_enough_to_intersect = 0 <= t && t <= 1
+  
+  if (long_enough_to_intersect && collinear) {
+    ctx.fillStyle = "#f00"
+  }
+  else if (is_on_line) {
+    ctx.fillStyle = "#0f0"
+  }
+  else {
+    ctx.fillStyle = "#000"
+  }
+  
+  drawPoint(intersect)
+}
+function drawLine (pa, pb, color) {
+  ctx.fillStyle = color
+  ctx.strokeStyle = color
+  var x1 = pa.a
+  var y1 = pa.b
+  var x2 = pb.a
+  var y2 = pb.b
+  drawArrow(ctx, x1, y1, x2, y2)
+}
+function drawPoint (p) {
+  var x = p.a - r
+  var y = p.b - r
+  ctx.fillRect(x, y, r*2, r*2)
+}
+function perp (va, vb) {
+	return (va.y.a - va.x.a) * (vb.y.b - vb.x.b) - (va.y.b - va.x.b) * (vb.y.a - vb.x.a)
+}
+function is_collinear (n, vec) {
+  var on_x, on_y
+  
+  if (vec.x.a < vec.y.a) {
+    on_x = vec.x.a <= n && n <= vec.y.a
+  }
+  else {
+    on_x = vec.x.a >= n && n >= vec.y.a
+  }
+  
+  if (vec.x.b < vec.y.b) {
+    on_y = vec.x.b <= n && n <= vec.y.b
+  }
+  else {
+    on_y = vec.x.b >= n && n >= vec.y.b
+  }
+  
+  return !! (on_x && on_y)
+}
+
+function animate(){
+  requestAnimationFrame(animate)
+  draw()
+}
+animate()
+
+</script>
-- 
cgit v1.2.3-70-g09d2


From 946dad6823a9206d1005f14f9ab1174234682e92 Mon Sep 17 00:00:00 2001
From: Jules Laplace <jules@okfoc.us>
Date: Thu, 30 Oct 2014 18:27:33 -0400
Subject: z

---
 public/assets/test/intersect.html | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'public/assets/test/intersect.html')

diff --git a/public/assets/test/intersect.html b/public/assets/test/intersect.html
index 3f6d110..cdce645 100644
--- a/public/assets/test/intersect.html
+++ b/public/assets/test/intersect.html
@@ -77,7 +77,7 @@ function draw () {
   if (long_enough_to_intersect && collinear) {
     ctx.fillStyle = "#f00"
   }
-  else if (is_on_line) {
+  else if (collinear) {
     ctx.fillStyle = "#0f0"
   }
   else {
-- 
cgit v1.2.3-70-g09d2


From 3cf89843698a52029be64e085051b19471d61174 Mon Sep 17 00:00:00 2001
From: Jules Laplace <jules@okfoc.us>
Date: Thu, 30 Oct 2014 18:32:45 -0400
Subject: agh

---
 public/assets/test/intersect.html | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

(limited to 'public/assets/test/intersect.html')

diff --git a/public/assets/test/intersect.html b/public/assets/test/intersect.html
index cdce645..0a8526e 100644
--- a/public/assets/test/intersect.html
+++ b/public/assets/test/intersect.html
@@ -71,7 +71,7 @@ function draw () {
   intersect.a = vec_a.x.a + ( vec_a.y.a - vec_a.x.a ) * t
   intersect.b = vec_a.x.b + ( vec_a.y.b - vec_a.x.b ) * t
   
-  var collinear = is_collinear( intersect.b, vec_b )
+  var collinear = is_collinear( intersect, vec_b )
   var long_enough_to_intersect = 0 <= t && t <= 1
   
   if (long_enough_to_intersect && collinear) {
@@ -103,23 +103,23 @@ function drawPoint (p) {
 function perp (va, vb) {
 	return (va.y.a - va.x.a) * (vb.y.b - vb.x.b) - (va.y.b - va.x.b) * (vb.y.a - vb.x.a)
 }
-function is_collinear (n, vec) {
+function is_collinear (p, vec) {
   var on_x, on_y
   
   if (vec.x.a < vec.y.a) {
-    on_x = vec.x.a <= n && n <= vec.y.a
+    on_x = vec.x.a <= p.a && p.a <= vec.y.a
   }
   else {
-    on_x = vec.x.a >= n && n >= vec.y.a
+    on_x = vec.x.a >= p.a && p.a >= vec.y.a
   }
   
   if (vec.x.b < vec.y.b) {
-    on_y = vec.x.b <= n && n <= vec.y.b
+    on_y = vec.x.b <= p.b && p.b <= vec.y.b
   }
   else {
-    on_y = vec.x.b >= n && n >= vec.y.b
+    on_y = vec.x.b >= p.b && p.b >= vec.y.b
   }
-  
+
   return !! (on_x && on_y)
 }
 
-- 
cgit v1.2.3-70-g09d2


From 0bf5e2b24d9037ef1cb4f7b435892b44d2070aac Mon Sep 17 00:00:00 2001
From: Jules Laplace <jules@okfoc.us>
Date: Thu, 30 Oct 2014 18:35:36 -0400
Subject: tab

---
 public/assets/test/intersect.html | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

(limited to 'public/assets/test/intersect.html')

diff --git a/public/assets/test/intersect.html b/public/assets/test/intersect.html
index 0a8526e..5e16f2e 100644
--- a/public/assets/test/intersect.html
+++ b/public/assets/test/intersect.html
@@ -101,7 +101,7 @@ function drawPoint (p) {
   ctx.fillRect(x, y, r*2, r*2)
 }
 function perp (va, vb) {
-	return (va.y.a - va.x.a) * (vb.y.b - vb.x.b) - (va.y.b - va.x.b) * (vb.y.a - vb.x.a)
+  return (va.y.a - va.x.a) * (vb.y.b - vb.x.b) - (va.y.b - va.x.b) * (vb.y.a - vb.x.a)
 }
 function is_collinear (p, vec) {
   var on_x, on_y
-- 
cgit v1.2.3-70-g09d2


From 2c2c70965efb50b500799ae7966a42e86bbac480 Mon Sep 17 00:00:00 2001
From: Julie Lala <jules@okfoc.us>
Date: Fri, 31 Oct 2014 10:18:39 -0400
Subject: fix floating point error :-P

---
 public/assets/javascripts/rectangles/models/rect.js |  6 ++++++
 public/assets/javascripts/rectangles/models/vec2.js |  5 ++++-
 public/assets/test/intersect.html                   | 15 +++++++++++----
 3 files changed, 21 insertions(+), 5 deletions(-)

(limited to 'public/assets/test/intersect.html')

diff --git a/public/assets/javascripts/rectangles/models/rect.js b/public/assets/javascripts/rectangles/models/rect.js
index 00f2c55..c667cf5 100644
--- a/public/assets/javascripts/rectangles/models/rect.js
+++ b/public/assets/javascripts/rectangles/models/rect.js
@@ -169,6 +169,12 @@
 		var s = "[" + this.x.toString() + " " + this.y.toString() + "] " + sides
 		return s
 	}
+	Rect.prototype.exactString = function(){
+		var sides = sidesToString(this.sides)
+		var s = "[" + this.x.exactString() + " " + this.y.exactString() + "] " + sides
+		return s
+	}
+	
 	Rect.prototype.serialize = function(){
 		return { x: this.x.serialize(), y: this.y.serialize() }
 	}
diff --git a/public/assets/javascripts/rectangles/models/vec2.js b/public/assets/javascripts/rectangles/models/vec2.js
index 49613c3..f28df54 100644
--- a/public/assets/javascripts/rectangles/models/vec2.js
+++ b/public/assets/javascripts/rectangles/models/vec2.js
@@ -200,7 +200,10 @@
 	}
 
 	vec2.prototype.toString = function(){
-		return "[" + ~~this.a + " " + ~~this.b + "]"
+		return "[" + round(this.a) + " " + round(this.b) + "]"
+	}
+	vec2.prototype.exactString = function(){
+		return "[" + this.a + " " + this.b + "]"
 	}
 	vec2.prototype.serialize = function(){
 		return [ ~~this.a, ~~this.b ]
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)
-- 
cgit v1.2.3-70-g09d2