Optimize raycast in sweep

chameleonic.p8

@@ -138,6 +138,41 @@ function _rast(
  _add()
 end
 
+-->8
+-- anchor operations (for the rope code)
+
+function _anch_eq(a0,a1) 
+ if (a0 and a1) return a0[1]==a1[1] and a0[2]==a1[2]
+ return a0==a1
+end
+--[[
+function _anch_unpack(anch)
+ assert(anch[1])
+ assert(anch[2])
+ return anch[1],anch[2]
+end
+]]--
+_anch_unpack=unpack
+
+function _anch_new(prev,next,xy)
+ local out={prev=prev,next=next,_anch_unpack(xy)}
+ if (prev) prev.next=out
+ if (next) next.prev=out
+ return out
+end
+
+function _anch_del(n1,xy)
+ local n0,n2=n1.prev,n1.next
+ if (n0) n0.next=n2
+ if (n2) n2.prev=n0
+end
+
+function _anch_update(a0,a1)
+ a0[1]=a1[1]
+ a0[2]=a1[2]
+end
+
+
 
 -->8
 -- input
@@ -373,7 +408,7 @@ function level:recollide_reanchor()
     ) then
      local key="GEOM"..mx0..","..my0..","..dx..","..dy
      anch_new[key]= {
-      ax=max(mx0,mx1),ay=max(my0,my1),adx=-dx,ady=-dy
+      max(mx0,mx1),max(my0,my1),adx=-dx,ady=-dy
      }
     end
    end
@@ -384,7 +419,7 @@ function level:recollide_reanchor()
    local mx0,my0=cr.mx,cr.my
    local mx1,my1=mx0+dx,my0+dy
    anch_new[key]={
-    ax=max(mx0,mx1),ay=max(my0,my1),adx=-dx,ady=-dy
+    max(mx0,mx1),max(my0,my1),adx=-dx,ady=-dy
    }
   end
  end
@@ -394,17 +429,19 @@ function level:recollide_reanchor()
   local old=(self._anch or {})[k]
   if old then
    anch_new[k]=new
-   if (old.ax!=new.ax or old.ay!=new.ay) add(moves,{old.ax,old.ay,new.ax,new.ay,old,key=k})
+   if (not _anch_eq(old,new)) add(moves,{old,new,key=k})
   end
  end
  self._anch=anch_new
  self._anch_keys={}
- for k,_ in pairs(self._anch) do
+ self._anch_by_position={}
+ for k,v in pairs(self._anch) do
   add(self._anch_keys,{key=k})
+  local pkey=_mix(_anch_unpack(v))
+  self._anch_by_position[pkey]=self._anch_by_position[pkey] or v
  end
  shellsort(self._anch_keys)
  shellsort(moves)
- --printh("!!STARTING!!")
 
  if player.rope then
   player.rope:experience_anchor_moves(moves)
@@ -428,10 +465,8 @@ function level:anchor_points()
  end
 end
 
-function level:anchor_at(ax,ay)
- for i in self:anchor_points() do
-  if (i.ax==ax and i.ay==ay) return i
- end
+function level:anchor_at(point)
+ return self._anch_by_position[_mix(_anch_unpack(point))]
 end
 
 function level:get_open_pit(mx,my)
@@ -485,10 +520,6 @@ function level:_mget(mx,my)
  )
 end
 
-function _amix(ax,ay)
- return ax..","..ay
-end
-
 function _mix(mx,my)
   return mx..","..my
 end
@@ -672,8 +703,8 @@ function player:update()
     while not level:mcoll(x,y) do x+=dx y+=dy end
 
     self.rope=rope:new(
-     x+0.5-dx*0.5,y+0.5-dy*0.5,
-     self.x+0.5,self.y+0.5,
+     {x+0.5-dx*0.5,y+0.5-dy*0.5},
+     {self.x+0.5,self.y+0.5},
      level:get_latch(dx,dy,x*8,y*8)
     )
     
@@ -700,10 +731,10 @@ function player:update()
    self.y=latch.rec.my+latch.dy
   end
 
-  self.rope:drag_dst(
+  self.rope:drag_dst{
    self.x+self.px/8+0.5,
    self.y+self.py/8+0.5
-  )
+  }
 
   local tdx,tdy=self.rope:tug_orientxy()
   if (tdx) self.orientx=tdx
@@ -815,19 +846,15 @@ rope={}
 rope.__index=rope
 
 function rope:new(
- src_ax,src_ay,dst_ax,dst_ay,latch
+ src,dst,latch
 )
  local r={
   id=0,
-  anchors={
-   {ax=src_ax,ay=src_ay},
-   {ax=dst_ax,ay=dst_ay}
-  },
   state={name="cast",frame=0},
   latch=latch,
  }
- r.src=r.anchors[1]
- r.dst=r.anchors[2]
+ r.src=src
+ r.dst=dst
  r.src.next=r.dst
  r.dst.prev=r.src
  setmetatable(r,rope)
@@ -855,10 +882,10 @@ function rope:update()
   if (not self.latch) wrongbleep:bleep(5) self:destroy() return
 
   if self.latch.rec then
-   self:drag_src(
+   self:drag_src{
     self.latch.rec.mx+0.5+self.latch.ax_offset,
     self.latch.rec.my+0.5+self.latch.ay_offset
-   )
+   }
 
    if self.latch.rec.dead==true then 
     self:destroy()
@@ -991,7 +1018,7 @@ function rope:draw(artificial_px,artificial_py)
  local sy=0
  while true do
   if (n1==nil) break
-  local anch=level:anchor_at(n1.ax,n1.ay)
+  local anch=level:anchor_at(n1)
   local x=n1.ax*8
   local y=n1.ay*8
   if anch then
@@ -1032,18 +1059,18 @@ function rope:draw(artificial_px,artificial_py)
   ]]
 end
 
-function rope:drag_dst(x,y)
- self:drag(self.dst,x,y)
+function rope:drag_dst(xy)
+ self:drag(self.dst,xy)
 end
 
-function rope:drag_src(x,y)
- self:drag(self.src,x,y)
+function rope:drag_src(xy)
+ self:drag(self.src,xy)
 end
 
-function rope:drag(n1,ax_new,ay_new)
+function rope:drag(n1,axy)
  self:relax()
- self:_drag(n1,ax_new,n1.ay)
- self:_drag(n1,ax_new,ay_new)
+ self:_drag(n1,{axy[1],n1[2]})
+ self:_drag(n1,axy)
  self:relax()
 end
 
@@ -1053,11 +1080,8 @@ function rope:relax()
   local n1=n0.next
   if (not n1) break
   local n2=n1.next
-
-
-  if n0.ax==n1.ax and n0.ay==n1.ay then 
-   n0.next=n2 
-   if (n2) n2.prev=n0
+  if _anch_eq(n0,n1) then
+   _anch_del(n1)
   else
    n0=n0.next
   end
@@ -1070,20 +1094,11 @@ function rope:relax()
   local n2=n1.next
   if (not n2) return
 
-  local x0,y0=n0.ax,n0.ay
-  local x1,y1=n1.ax,n1.ay
-  local x2,y2=n2.ax,n2.ay
-
-  local anch=level:anchor_at(n1.ax,n1.ay)
-  local would,x1_new,y1_new=would_stick(anch,x0,y0,x1,y1,x2,y2)
-  if not would and not (n1.ax==x1_new and n1.ay==y1_new) then
-   self:_drag(n1,x1_new,y1_new,n1.ax,n1.ay)
-   n0=n1.prev
-   n2=n1.next
-   n0.next=n2
-   n2.prev=n0
-   n1.next=nil
-   n1.prev=nil
+  local anch=level:anchor_at(n1)
+  local wouldstick,position_new=would_stick(anch,n0,n1,n2)
+  if not (wouldstick or _anch_eq(n1,position_new)) then
+   self:_drag(n1,position_new,{_anch_unpack(n1)})
+   _anch_del(n1)
   else n0=n0.next end
  end
 end
@@ -1099,7 +1114,9 @@ function rope:_check_sane()
   local n1=n0.next
   if (not n1) break 
 
-  _rast(qxs,qys,flr(n0.ax*2),flr(n0.ay*2),flr(n1.ax*2),flr(n1.ay*2)) 
+  local n0ax,n0ay=_anch_unpack(n0)
+  local n1ax,n1ay=_anch_unpack(n1)
+  _rast(qxs,qys,flr(n0ax*2),flr(n0ay*2),flr(n1ax*2),flr(n1ay*2)) 
   n0=n1
  end
 
@@ -1143,7 +1160,6 @@ function rope:_check_sane()
 
       if dmx==1 and dmy==1 and level:mcoll(mx0,my2) and level:mcoll(mx2,my0) then
       else
-       --printh("ok! "..tostring({qxs[i-2],qys[i-2]})..tostring({qxs[i],qys[i]})..tostring(m0)..tostring(m2))
        ok=true
       end
      end
@@ -1156,12 +1172,12 @@ function rope:_check_sane()
  return true
 end
 
-function would_stick(anchor,x0,y0,x1,y1,x2,y2)
- x1,y1=x1 or anchor.ax,y1 or anchor.ay
+function would_stick(anchor,xy0,xy1,xy2)
+ local x0,y0=_anch_unpack(xy0)
+ local x1,y1=_anch_unpack(xy1 or anchor)
+ local x2,y2=_anch_unpack(xy2)
 
  local dx,dy=x2-x0,y2-y0
- if (x1==x0 and y1==y0) return 
- if (x1==x2 and y1==y2) return 
 
  local function switch_ends() 
   dx,dy,x0,y0,x2,y2=-dx,-dy,x2,y2,x0,y0
@@ -1185,7 +1201,7 @@ function would_stick(anchor,x0,y0,x1,y1,x2,y2)
 
  return 
   anchor and anchor.adx==adx and anchor.ady==ady,
-  x1_new,y1_new
+  {x1_new,y1_new}
 end
 
 function rope:experience_anchor_moves(moves)
@@ -1198,15 +1214,15 @@ function rope:_be_dragged_by(moves)
  local n=self.src
  while n do
   for t in all(moves) do
-   local ax_old,ay_old,ax_new,ay_new=unpack(t)
-   if (ax_old==n.ax and ay_old==n.ay) n.dest={ax_new,ay_new} break
+   local xy_old,xy_new=unpack(t)
+   if (_anch_eq(xy_old,n)) n.dest=xy_new break
   end
   n=n.next
  end
 
  n=self.src
  while n do
-  if (n.dest) self:_drag(n,unpack(n.dest)) n.dest=nil
+  if (n.dest) self:_drag(n,n.dest) n.dest=nil
   n=n.next
  end
 end
@@ -1217,14 +1233,18 @@ function rope:_be_pushed_by(moves)
  end
 end
 
-function rope:_be_pushed_by1(ax_old,ay_old,ax_new,ay_new,anch)
+function rope:_be_pushed_by1(anch_old,anch_new)
  local n0=self.src
- while true do
+
+ local ax_old,ay_old=_anch_unpack(anch_old)
+ local ax_new,ay_new=_anch_unpack(anch_new)
+
+ while n0 do
   n1=n0.next
   if (not n1) return
 
-  local nx0,ny0=n0.ax,n0.ay
-  local nx1,ny1=n1.ax,n1.ay
+  local nx0,ny0=_anch_unpack(n0)
+  local nx1,ny1=_anch_unpack(n1)
 
   local nxmn,nxmx = _mnmx(nx0,nx1)
   local nymn,nymx = _mnmx(ny0,ny1)
@@ -1233,9 +1253,9 @@ function rope:_be_pushed_by1(ax_old,ay_old,ax_new,ay_new,anch)
    (ax_new!=ax_old or (nxmn<ax_new and ax_new<nxmx)) and 
    (ay_new!=ay_old or (nymn<ay_new and ay_new<nymx)) and 
 
-   (_which_side(ax_old,ay_old,nx0,ny0,nx1,ny1)!= 
-    _which_side(ax_new,ay_new,nx0,ny0,nx1,ny1) 
-   ) and would_stick(anch,nx0,ny0,nil,nil,nx1,ny1)
+   (_which_side(anch_old,n0,n1)!= 
+    _which_side(anch_new,n0,n1) 
+   ) and would_stick(anch_new,n0,nil,n1)
   then
    local nx05,ny05
    if ax_new==ax_old then
@@ -1246,101 +1266,84 @@ function rope:_be_pushed_by1(ax_old,ay_old,ax_new,ay_new,anch)
     nx05=nx0+(ny05-ny0)/(ny1-ny0) * (nx1-nx0)
    end
 
-   local n05={ax=nx05,ay=ny05,prev=n0,next=n1}
-   n0.next=n05
-   n1.prev=n05
-   -- printh("creating: "..tostring{anch,{n0.ax,n0.ay},{n05.ax,n05.ay},{n1.ax,n1.ay}})
-   -- printh("dragging: "..tostring{anch,{n05.ax,n05.ay},{ax_new,ay_new}})
-   self:_drag(n05,ax_new,ay_new)
+   local n05=_anch_new(n0,n1,{nx05,ny05})
+   self:_drag(n05,{ax_new,ay_new})
   else
    n0=n0.next
   end
  end
 end
 
-function rope:_drag(n1,ax1_new,ay1_new,ax_removing,ay_removing)
- local function _sweep_radar(ax_lhs,ay_lhs,ax_rhs,ay_rhs,ax_pivot,ay_pivot,ax_far0,ay_far0,ax_far1,ay_far1)
+function rope:_drag(n1,new,removing)
+ local function _sweep_radar(lhs,rhs,pivot,src,dst)
+  if (_anch_eq(src,dst)) return
+
   local function _uncreatable(anchor)
-   return (anchor.ax==ax_lhs and anchor.ay==ay_lhs) or
-    (anchor.ax==ax_rhs and anchor.ay==ay_rhs) or
-    (anchor.ax==ax_removing and anchor.ay==ay_removing)
+   return _anch_eq(anchor,lhs) or _anch_eq(anchor,lhs) or _anch_eq(anchor,removing)
   end
 
-  if (ax_far0==ax_far1 and ay_far0==ay_far1) return 
+  local function _sweep(extent_orig,extent_final,cb_in_bounds,cb_make_point)
+   local eligible={}
+   local point_orig=cb_make_point(extent_orig)
+   local point_final=cb_make_point(extent_final)
 
-  if ax_far0==ax_far1 then
-   local ax_far=ax_far0
-   local ax0,ax1=_mnmx(ax_pivot,ax_far)
-
-   ay_far_old=ay_far0
-   for ay_far_new in _stepfrom(ay_far0,ay_far1) do
    for anchor in level:anchor_points() do
-     if 
-      not _uncreatable(anchor) and
-      (ax0<=anchor.ax and anchor.ax<=ax1) and 
-      would_stick(anchor,ax_pivot,ay_pivot,nil,nil,ax_far,ay_far_new) and
-      (
-        _which_side(anchor.ax,anchor.ay,ax_pivot,ay_pivot,ax_far,ay_far_old) !=
-        _which_side(anchor.ax,anchor.ay,ax_pivot,ay_pivot,ax_far,ay_far_new)
-      )
-     then
-      return anchor
-     end
-    end
-    ay_far_old=ay_far_new
-   end
-  elseif ay_far0==ay_far1 then
-   local ay_far=ay_far0
-   local ay0,ay1=_mnmx(ay_pivot,ay_far)
+    -- figure out which anchors we even can stick to
+    if cb_in_bounds(anchor) and not _uncreatable(anchor) then 
+     local side_orig=_which_side(anchor,pivot,point_orig)
+     local side_final=_which_side(anchor,pivot,point_final)
 
-   ax_far_old=ax_far0
-   for ax_far_new in _stepfrom(ax_far0,ax_far1) do
-    for anchor in level:anchor_points() do
-     if 
-      not _uncreatable(anchor) and
-      (ay0<=anchor.ay and anchor.ay<=ay1) and 
-      would_stick(anchor,ax_pivot,ay_pivot,nil,nil,ax_far_new,ay_far) and
-      (
-        _which_side(anchor.ax,anchor.ay,ax_pivot,ay_pivot,ax_far_old,ay_far) !=
-        _which_side(anchor.ax,anchor.ay,ax_pivot,ay_pivot,ax_far_new,ay_far)
-      )
-     then
-      return anchor
+     if (side_orig!=side_final and would_stick(anchor,pivot,nil,point_final)) add(eligible,{anchor,side_final})
     end
    end
-    ax_far_old=ax_far_new
+
+   -- if no one's in the race, don't raycast
+   if (#eligible==0) return 
+   if (#eligible==1) return eligible[1][1]
+
+   -- see who wins the race
+   for extent in _stepfrom(extent_orig,extent_final) do
+    local point = cb_make_point(extent)
+    for anchor_final in all(eligible) do
+     if (_which_side(anchor_final[1],pivot,point)==anchor_final[2]) return anchor_final[1]
     end
    end
   end
 
- local ax1_old,ay1_old=n1.ax,n1.ay
- n1.ax=ax1_new
- n1.ay=ay1_new
+  local ax_pivot,ay_pivot=_anch_unpack(pivot)
+  local ax_src,ay_src=_anch_unpack(src)
+  local ax_dst,ay_dst=_anch_unpack(dst)
+
+  if ax_src==ax_dst then
+   return _sweep(
+    ay_src,ay_dst,
+    function(anchor) return mid(ax_pivot,anchor[1],ax_dst)==anchor[1] end,
+    function(ay) return {ax_dst,ay} end
+   )
+  else
+   return _sweep(
+    ax_src,ax_dst,
+    function(anchor) return mid(ay_pivot,anchor[2],ay_dst)==anchor[2] end,
+    function(ax) return {ax,ay_dst} end
+   )
+  end
+ end
+
+ local old={_anch_unpack(n1)}
+ _anch_update(n1,new)
 
  local n0=n1.prev
  while n0 do
-  local anch=_sweep_radar(
-   n0.ax,n0.ay,n1.ax,n1.ay,
-   n0.ax,n0.ay,ax1_old,ay1_old,ax1_new,ay1_new
-   )
+  local anch=_sweep_radar(n0,n1,n0,old,new)
   if (not anch) break
-  local n05={ax=anch.ax,ay=anch.ay,prev=n0,next=n1}
-  n0.next=n05
-  n1.prev=n05
-  n0=n05
+  n0=_anch_new(n0,n1,anch)
  end
 
  local n2=n1.next
  while n2 do
-  local anch=_sweep_radar(
-   n1.ax,n1.ay,n2.ax,n2.ay,
-   n2.ax,n2.ay,ax1_old,ay1_old,ax1_new,ay1_new
-  )
+  local anch=_sweep_radar(n1,n2,n2,old,new)
   if (not anch) break
-  local n15={ax=anch.ax,ay=anch.ay,prev=n1,next=n2}
-  n1.next=n15
-  n2.prev=n15
-  n2=n15
+  n2=_anch_new(n1,n2,anch)
  end
 end
 
@@ -1353,9 +1356,7 @@ function _stepfrom(x0,x1)
   end
  end
 
- local mul=0.5
- x0*=2
- x1*=2
+ local mul=1
  if (x0>x1) x0,x1,mul=-x0,-x1,-mul
  local i=flr(x0)
  local top=flr(x1)
@@ -1371,7 +1372,11 @@ function _stepfrom(x0,x1)
  end
 end
 
-function _which_side(x,y,x0,y0,x1,y1)
+function _which_side(xy,x0y0,x1y1)
+ local x,y=_anch_unpack(xy)
+ local x0,y0=_anch_unpack(x0y0)
+ local x1,y1=_anch_unpack(x1y1)
+
  return sgn0((x1-x0)*(y-y0) - (y1-y0)*(x-x0))
 end
 
@@ -1399,7 +1404,8 @@ function rope:collide_mrect(mx0,my0,mw,mh,exclude_src,exclude_dst)
    if (not nd) return
   end
 
-  local x1,y1,x2,y2=n0.ax,n0.ay,n1.ax,n1.ay
+  local x1,y1=_anch_unpack(n0)
+  local x2,y2=_anch_unpack(n1)
   local function _line_line(x3,y3,x4,y4)
    local denom=(y4-y3)*(x2-x1)-(x4-x3)*(y2-y1)
 
@@ -1429,12 +1435,15 @@ end
 function rope:tug_orientxy()
  local a1=self.dst
  local a0=self.dst.prev
- local dx=a0.ax-a1.ax
+ local ax0,ay0=_anch_unpack(a0)
+ local ax1,ay1=_anch_unpack(a1)
+
+ local dx=ax0-ax1
  local tdx
  if (dx>3/8) tdx=1
  if (dx<-3/8) tdx=-1
 
- local dy=a0.ay-a1.ay
+ local dy=ay0-ay1
  local tdy
  if abs(dy)>abs(dx)/2 then 
   if (dy>3/8) tdy=1
@@ -1619,11 +1628,12 @@ function rope:_anchors_simplified()
  end
  a=self.src
  while a do
+  local ax,ay=_anch_unpack(a)
   local point={
-   x=flr(a.ax*8+0.5),y=flr(a.ay*8+0.5),
-   ax=a.ax,ay=a.ay
+   ax,ay,
+   x=flr(ax*8+0.5),y=flr(ay*8+0.5),
   }
-  local aw=level:anchor_at(a.ax,a.ay)
+  local aw=level:anchor_at(a)
   local l=self.latch
   if aw then
    if (aw.adx==1) point.x-=1