Simplify rope recalculator (still slow)

chameleonic.p8

@@ -676,38 +676,76 @@ end
 function rope:_tidy_up_gen()
  if (self:busy()) return
 
- for i=0,#self.ancs+1 do
-  local a=self:_anc(i)
-  a.dirty=true
- end
+ if (self.under_destruction) return
 
- local a=0
- while a<=#self.ancs+1 do
-  local anc=self:_anc(a)
-  if anc.dirty and #anc.todo==0 then
-   while not self.under_destruction and (
-    self:_find_needed_anchors(a) or 
-    self:_find_touched_anchors(a) or
-    self:_elide_point(a) 
-   ) do end
-
-   anc.dirty=false
-   a=0
-  else
+ local settled=true
+ local touched={}
+ local loop=function(f)
+  local a=0
+  while a<=#self.ancs+1 do
+   local anc=self:_anc(a)
+   if anc.dirty then
+    anc.seen=true
+    if self[f](self,a) then
+     settled=false anc.changed=true 
+    end
+   end
    a+=1
   end
  end
+
+ local mark_unseen=function()
+  touched={}
+  for a=0,#self.ancs+1,1 do
+   local anc=self:_anc(a)
+   anc.seen=false
+   anc.changed=false
+  end
+ end
+
+ local propagate_dirty=function(f)
+  for a=0,#self.ancs+1,1 do
+   local a1=self:_anc(a)
+   if a1.dirty then
+    local a0=self:_anc(a-1)
+    if (a0!=nil) a0.dirty=true
+
+    local a2=self:_anc(a+1)
+    if (a2!=nil) a2.dirty=true
+   end
+  end
+ end
+
+ while true do
+  settled=true
+
+  mark_unseen()
+  propagate_dirty()
+
+  loop("_find_needed_anchors")
+  loop("_find_touched_anchors")
+  loop("_elide_point")
+
+  for a=0,#self.ancs+1,1 do
+   local anc=self:_anc(a)
+   if anc.seen then 
+    anc.dirty=anc.changed
+   end
+  end
+
+  if (settled) break
+ end
 end
 
 function rope:_drag1(
  i,x,y
 )
- local a_old=self:_anc(i)
- local a_new={x=x,y=y}
- if (_point_eq(a_old, a_new)) return
+ local a=self:_anc(i)
+ if (_point_eq(a, {x=x,y=y})) return
  
- a_old.x=x
- a_old.y=y
+ a.x=x
+ a.y=y
+ a.dirty=true
 end
 
 function rope:_find_needed_anchors(i)
@@ -741,11 +779,9 @@ function rope:_find_needed_anchors(i)
    self:_can_stretch(a1,a2)
   then
    local id=self.id
-   add(self.ancs,{id=id,x=a1.x,y=a1.y,todo={}},i)
+   add(self.ancs,{id=id,x=a1.x,y=a1.y,dirty=true,todo={}},i)
    self.id+=1
 
-   self:_anc(i-1).dirty=true
-   self:_anc(i+1).dirty=true
    return true
   end
  end
@@ -765,12 +801,9 @@ function rope:_find_touched_anchors(i)
    -- and self:_can_stretch(p,a2)
   then
    local id=self.id
-   add(self.ancs,{id=id,x=a1.x,y=a1.y,todo={}},i)
+   add(self.ancs,{id=id,x=a1.x,y=a1.y,dirty=true,todo={}},i)
    self.id+=1
 
-   self:_anc(i-1).dirty=true
-   self:_anc(i+1).dirty=true
-
    return true
   end
  end
@@ -808,8 +841,6 @@ function rope:_elide_point(i)
  end
  
  deli(self.ancs,i)
- self:_anc(i-1).dirty=true
- self:_anc(i).dirty=true
  return true
 end
 
@@ -1034,7 +1065,6 @@ function rope:_tug()
       if force or not level:pcoll(x,y) then
        s.x=x
        s.y=y
-       s.dirty=true
       end
       return true
      end}
@@ -1048,7 +1078,6 @@ function rope:_tug()
    end 
    for node=ancs[i-1].ix-1,ancs[i].ix+1 do
     local anc=self:_anc(node)
-    if (anc!=nil) anc.dirty=true
    end
    return
   end