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

---
 .../javascripts/rectangles/engine/rooms/mover.js   | 95 ++++++++++++++++------
 1 file changed, 71 insertions(+), 24 deletions(-)

(limited to 'public/assets/javascripts/rectangles')

diff --git a/public/assets/javascripts/rectangles/engine/rooms/mover.js b/public/assets/javascripts/rectangles/engine/rooms/mover.js
index 121ecec..8ce00fe 100644
--- a/public/assets/javascripts/rectangles/engine/rooms/mover.js
+++ b/public/assets/javascripts/rectangles/engine/rooms/mover.js
@@ -36,6 +36,18 @@ Rooms.mover = new function(){
 			// check if we've breached one of the walls.. clamp position if so
 			var collision = base.room.collidesDisc(cam, pos, radius)
 
+			if (collision && ! base.noclip) {
+				cam.x = (collision & LEFT_RIGHT) ? base.room.rect.x.clampDisc(pos.x, radius) : pos.x
+				cam.z = (collision & FRONT_BACK) ? base.room.rect.y.clampDisc(pos.z, radius) : pos.z
+				return
+			}
+
+			// in this case, we appear to have left the room..
+			// $(".face.active").removeClass("active")
+			Walls.clearBodyColor()
+			base.room = null
+		}
+
 /*
       var dz = new vec2( cam.z, pos.z )
       dz.normalize()
@@ -43,47 +55,82 @@ Rooms.mover = new function(){
       var dx = new vec2( cam.x, pos.x )
       dx.normalize()
 
+      // first check if the cam-pos movement intersects the wall.
+      // next check if it intersects any of the surface frames
+      // if we can pass through the wall at this point, we do not need to clamp.
+      // otherwise, get the distance along the cam-pos vector where we would hit the wall and clamp to it.
 			Walls.list.forEach(function(wall){
+			  var t = -1
 			  switch (wall.side) {
 			    case FRONT:
+			      if (cam.z >= wall.edge + radius && wall.edge + radius >= pos.z && wall.vec.intersects(dx) ) {
+			        t = check_intersection( front_back_intersection, cam, pos, dx, wall, radius )
+			      }
 			      break
 			    case BACK:
+			      // console.log(cam.z|0, wall.edge-radius, pos.z|0, wall.vec.intersects(dx))
+			      if (cam.z <= wall.edge - radius && wall.edge - radius <= pos.z && wall.vec.intersects(dx) ) {
+			        t = check_intersection( front_back_intersection, cam, pos, dx, wall, -radius )
+			        console.log(t)
+			      }
 			      break
 			    case LEFT:
-			      if (cam.x >= wall.edge + radius && wall.edge + radius >= pos.x && (wall.vec.intersects(dz) ) {
-			        // intersects the wall.. next check if it intersects any of the surface frames
-			        wall.surface.faces.some(function(face, i){
-			          // if we can pass through the wall at this point, we do not need to clamp
-			          if (face.y.a === 0 && face.x.intersects(dz)) {
-			            dz.a = pos.z = face.x.clamp(pos.z)
-			            dz.b = cam.z
-			            dz.normalize()
-			            return true
-			          }
-			        })
+			      if (cam.x >= wall.edge + radius && wall.edge + radius >= pos.x && wall.vec.intersects(dz) ) {
+			        t = check_intersection( left_right_intersection, cam, pos, dz, wall, radius )
 			      }
 			      break
 			    case RIGHT:
-			      if (cam.x <= wall.edge - radius && wall.edge - radius <= pos.x && (wall.vec.contains(cam.z) || wall.vec.contains(pos.z)) ) {
-			        // intersects
+			      if (cam.x <= wall.edge - radius && wall.edge - radius <= pos.x && wall.vec.intersects(dz) ) {
+			        t = check_intersection( left_right_intersection, cam, pos, dz, wall, -radius )
 			      }
 			      break
 			  }
+        if (0 <= t && t <= 1) {
+          pos.x = cam.x + (pos.x - cam.x) * t
+          pos.z = cam.z + (pos.z - cam.z) * t
+
+          dz = new vec2( cam.z, pos.z )
+          dz.normalize()
+
+          dx = new vec2( cam.x, pos.x )
+          dx.normalize()
+        }
       })
-*/
 
-			if (collision && ! base.noclip) {
-				cam.x = (collision & LEFT_RIGHT) ? base.room.rect.x.clampDisc(pos.x, radius) : pos.x
-				cam.z = (collision & FRONT_BACK) ? base.room.rect.y.clampDisc(pos.z, radius) : pos.z
-				return
-			}
+    function check_intersection(intersection_function, cam, pos, cam_pos_vector, wall, radius) {
+      var t = -1
+      wall.surface.faces.some(function(face, i){
+        if (face.y.a == 0 && face.x.intersects(cam_pos_vector)) {
+          t = intersection_function( cam, pos, wall, face, radius )
+          console.log(">>", t)
+          if (0 <= t && t <= 1) {
+            return true
+          }
+          else {
+            t = -1
+          }
+        }
+        return false
+      })
+      return t
+    }
+		function left_right_intersection (cam, pos, wall, face, radius) {
+      var perp_n = (face.x.a - face.x.b) * (wall.edge - cam.z + radius)
+      var perp_d = (face.x.a - face.x.b) * (pos.z - cam.z)
+      if (perp_d == 0) return Infinity
+      return perp_n / perp_d
+    }
+		function front_back_intersection (cam, pos, wall, face, radius) {
+		  // va.vx*vb.vy - va.vy*vb.vx
+      var perp_n = (face.x.b - face.x.a) * (wall.edge - cam.x + radius)
+      var perp_d = (face.x.b - face.x.a) * (pos.x - cam.x)
 
-			// in this case, we appear to have left the room..
-			// $(".face.active").removeClass("active")
-			Walls.clearBodyColor()
-			base.room = null
-		}
+      console.log((pos.x - cam.x), wall.edge - cam.x, radius)
 
+      if (perp_d == 0) return Infinity
+      return perp_n / perp_d
+    }
+*/
 		// collision test failed, so update position
 		cam.x = pos.x
 		cam.z = pos.z
-- 
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/javascripts/rectangles')

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


From f599c7edf7e635241e839fc024e4016ae0dcc210 Mon Sep 17 00:00:00 2001
From: Jules Laplace <jules@okfoc.us>
Date: Fri, 31 Oct 2014 16:03:12 -0400
Subject: intersection test 2 - hit-testing on wall structure

---
 .../javascripts/rectangles/models/surface.js       |   9 +
 public/assets/test/intersect2.html                 | 218 +++++++++++++++++++++
 2 files changed, 227 insertions(+)
 create mode 100644 public/assets/test/intersect2.html

(limited to 'public/assets/javascripts/rectangles')

diff --git a/public/assets/javascripts/rectangles/models/surface.js b/public/assets/javascripts/rectangles/models/surface.js
index 3a6c449..fc4aae4 100644
--- a/public/assets/javascripts/rectangles/models/surface.js
+++ b/public/assets/javascripts/rectangles/models/surface.js
@@ -154,6 +154,15 @@
 		}
 		return -1
 	}
+	Surface.prototype.face_for_x = function(x, min_i){
+    min_i = min_i || 0
+		for (var i = min_i; i < this.faces.length; i++) {
+			if (this.faces[i].x.contains(x)) {
+				return this.faces[i]
+			}
+		}
+		return null
+	}
 
 	Surface.prototype.bounds_at_index_with_dimensions = function(index, dimensions){
     var faces = this.faces
diff --git a/public/assets/test/intersect2.html b/public/assets/test/intersect2.html
new file mode 100644
index 0000000..fade288
--- /dev/null
+++ b/public/assets/test/intersect2.html
@@ -0,0 +1,218 @@
+<style>
+body,html{margin:0;padding:0;}
+#hud { position: absolute; top: 0; left: 0; pointer-events: none; }
+</style>
+<canvas id="canvas"></canvas>
+<div id="hud"></div>
+
+<script src="/assets/javascripts/util.js"></script>
+<script src="/assets/javascripts/vendor/tube.js"></script>
+<script src="/assets/javascripts/vendor/bower_components/jquery/dist/jquery.min.js"></script>
+<script src="/assets/javascripts/vendor/bower_components/lodash/dist/lodash.min.js"></script>
+<script src="/assets/javascripts/mx/mx.js"></script>
+<script src="/assets/javascripts/mx/extensions/mx.scene.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/util/sort.js"></script>
+<script src="/assets/javascripts/rectangles/util/uid.js"></script>
+<script src="/assets/javascripts/rectangles/models/vec2.js"></script>
+<script src="/assets/javascripts/rectangles/models/rect.js"></script>
+<script src="/assets/javascripts/rectangles/models/room.js"></script>
+<script src="/assets/javascripts/rectangles/models/surface.js"></script>
+<script src="/assets/javascripts/rectangles/models/wall.js"></script>
+<script src="/assets/javascripts/rectangles/models/floor.js"></script>
+<script src="/assets/javascripts/rectangles/engine/rooms/_rooms.js"></script>
+<script src="/assets/javascripts/rectangles/engine/rooms/_walls.js"></script>
+<script src="/assets/javascripts/rectangles/engine/rooms/clipper.js"></script>
+<script src="/assets/javascripts/rectangles/engine/rooms/builder.js"></script>
+<script src="/assets/javascripts/rectangles/engine/rooms/grouper.js"></script>
+<script src="/assets/javascripts/vendor/canvasutilities.js"></script>
+<script>
+
+var ctx = canvas.getContext('2d')
+var scene = new MX.Scene()
+
+var w = canvas.width = window.innerWidth
+var h = canvas.height = window.innerHeight
+
+var cursor = new Rect( 150, 250, 150, 250 )
+var wall_vec = new Rect ( 0, 0, 0, 0 )
+var points = [ cursor.x, cursor.y ]
+
+var origins = new Rect()
+origins.x = cursor.x
+origins.y = wall_vec.x
+
+var radius = 1
+
+var rect       = new Rect( new vec2(100,400), new vec2(100,400) )
+var east       = new Rect( new vec2(200,600), new vec2(100,400) )
+var corner     = new Rect( new vec2(300,700), new vec2(300,700) )
+var peninsula  = new Rect( new vec2(400,600), new vec2(600,800) )
+var peninsula2 = new Rect( new vec2(650,750), new vec2(350,450) )
+
+var rect_room       = new Room({ id: "rect", rect: rect, height: 2 })
+var east_room       = new Room({ id: "east", rect: east, height: 2 })
+var corner_room     = new Room({ id: "corner", rect: corner, height: 2 })
+var peninsula_room  = new Room({ id: "peninsula", rect: peninsula, height: 3 })
+var peninsula2_room = new Room({ id: "peninsula2", rect: peninsula2, height: 3 })
+
+Rooms.add( rect_room )
+Rooms.add( east_room )
+Rooms.add( corner_room )
+Rooms.add( peninsula_room )
+Rooms.add( peninsula2_room )
+
+Rooms.clipper.update()
+Rooms.builder.build()
+Rooms.grouper.build()
+
+var r = 4
+
+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)
+
+  Rooms.forEach(function(room, i){
+    ctx.fillStyle = "#eee"
+    ctx.fillRect(room.rect.x.a, room.rect.y.a, room.rect.width(), room.rect.height())
+  })
+  
+  ctx.fillStyle = "#333"
+  points.forEach(drawPoint)
+  
+  drawLine(cursor.x, cursor.y, "#f00")
+  hud.innerHTML = ""
+  Walls.list.forEach(function(wall, i){
+    if (wall.side & LEFT_RIGHT) {
+      wall_vec.x.a = wall.edge
+      wall_vec.x.b = wall.vec.a
+      wall_vec.y.a = wall.edge
+      wall_vec.y.b = wall.vec.b
+    }
+    else {
+      wall_vec.x.a = wall.vec.a
+      wall_vec.x.b = wall.edge
+      wall_vec.y.a = wall.vec.b
+      wall_vec.y.b = wall.edge
+    }
+    drawLine(wall_vec.x, wall_vec.y, "#888", true)
+    drawLine(origins.x, origins.y, "rgba(0,0,0,0.1)")
+
+    var t = perp(origins, wall_vec) / ( perp(cursor, wall_vec) || 0.0000001 )
+    intersect.a = cursor.x.a + ( cursor.y.a - cursor.x.a ) * t
+    intersect.b = cursor.x.b + ( cursor.y.b - cursor.x.b ) * t
+
+    var collinear = is_collinear( intersect, wall_vec )
+    var long_enough_to_intersect = 0 <= t && t <= 1
+    var actually_intersects = false
+    var intersecting_face
+    var msg
+  
+    if (long_enough_to_intersect && collinear) {
+      if (wall.side & LEFT_RIGHT) {
+        intersecting_face = wall.surface.face_for_x(intersect.b)
+      }
+      else {
+        intersecting_face = wall.surface.face_for_x(intersect.a)
+      }
+      actually_intersects = !! (intersecting_face && intersecting_face.y.a == 0)
+    }
+    
+    if (actually_intersects) {
+      ctx.fillStyle = "#f00"
+      msg = "through"
+    }
+    else if (collinear) {
+      ctx.fillStyle = "#0f0"
+      msg = "to"
+    }
+    else {
+      ctx.fillStyle = "rgba(0,0,0,0.1)"
+      msg = "off"
+    }
+    
+    drawPoint(intersect)
+    if (intersecting_face) {
+      hud.innerHTML += intersecting_face.y.a + "<br>"
+    }
+  })
+
+}
+function drawLine (pa, pb, color, headless) {
+  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, 3, headless ? 0 : 1)
+}
+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 (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 <= pa && pa <= vec.y.a
+  }
+  else {
+    on_x = vec.x.a >= pa && pa >= vec.y.a
+  }
+  
+  if (vec.x.b < vec.y.b) {
+    on_y = vec.x.b <= pb && pb <= vec.y.b
+  }
+  else {
+    on_y = vec.x.b >= pb && pb >= vec.y.b
+  }
+
+  return !! (on_x && on_y)
+}
+
+function animate(){
+  requestAnimationFrame(animate)
+  draw()
+}
+animate()
+
+</script>
-- 
cgit v1.2.3-70-g09d2