X-Git-Url: http://deadsoftware.ru/gitweb?a=blobdiff_plain;f=src%2Fgame%2Fz_aabbtree.pas;h=79d9d8a62eeb8d58855e7e9e123c020e87fb093e;hb=a9c0a618b01fb1e51cc953ff8295f888890cc967;hp=8260d9e82aea1122836db9da2e21624f4c312909;hpb=fe14f41dc8700dee5a80949a41c58e7d3943f464;p=d2df-sdl.git

diff --git a/src/game/z_aabbtree.pas b/src/game/z_aabbtree.pas
index 8260d9e..79d9d8a 100644
--- a/src/game/z_aabbtree.pas
+++ b/src/game/z_aabbtree.pas
@@ -14,87 +14,88 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *)
 {$INCLUDE ../shared/a_modes.inc}
-{$DEFINE aabbtree_many_asserts}
+{.$DEFINE aabbtree_many_asserts}
 {$DEFINE aabbtree_query_count}
+{.$DEFINE aabbtree_use_floats}
 unit z_aabbtree;
 
 interface
 
-uses e_log;
+uses
+  e_log, g_grid;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
 type
-  Float = Single;
-  PFloat = ^Float;
-
-  TTreeFlesh = TObject;
+  {$IFDEF aabbtree_use_floats}TreeNumber = Single;{$ELSE}TreeNumber = Integer;{$ENDIF}
 
 
 // ////////////////////////////////////////////////////////////////////////// //
 type
   Ray2D = record
   public
-    origX, origY: Float;
-    dirX, dirY: Float;
+    origX, origY: Single;
+    dirX, dirY: Single;
 
   public
-    constructor Create (ax, ay: Float; aangle: Float); overload;
-    constructor Create (ax0, ay0, ax1, ay1: Float); overload;
-    constructor Create (const aray: Ray2D); overload;
+    constructor Create (ax, ay: Single; aangle: Single); overload;
+    constructor Create (ax0, ay0, ax1, ay1: Single); overload;
+    constructor Create (constref aray: Ray2D); overload;
 
-    procedure copyFrom (const aray: Ray2D); inline;
+    procedure copyFrom (constref aray: Ray2D); inline;
 
     procedure normalizeDir (); inline;
 
-    procedure setXYAngle (ax, ay: Float; aangle: Float); inline;
-    procedure setX0Y0X1Y1 (ax0, ay0, ax1, ay1: Float); inline;
+    procedure setXYAngle (ax, ay: Single; aangle: Single); inline;
+    procedure setX0Y0X1Y1 (ax0, ay0, ax1, ay1: Single); inline;
   end;
 
 // ////////////////////////////////////////////////////////////////////////// //
 type
   AABB2D = record
   public
-    minX, minY, maxX, maxY: Float;
+    minX, minY, maxX, maxY: TreeNumber;
 
   private
     function getvalid (): Boolean; inline;
-    function getcenterX (): Float; inline;
-    function getcenterY (): Float; inline;
-    function getextentX (): Float; inline;
-    function getextentY (): Float; inline;
+    function getcenterX (): TreeNumber; inline;
+    function getcenterY (): TreeNumber; inline;
+    function getextentX (): TreeNumber; inline;
+    function getextentY (): TreeNumber; inline;
 
   public
-    constructor Create (x0, y0, x1, y1: Float); overload;
-    constructor Create (const aabb: AABB2D); overload;
-    constructor Create (const aabb0, aabb1: AABB2D); overload;
+    constructor Create (x0, y0, x1, y1: TreeNumber); overload;
+    constructor Create (constref aabb: AABB2D); overload;
+    constructor Create (constref aabb0, aabb1: AABB2D); overload;
+
+    constructor CreateWH (ax, ay, w, h: TreeNumber);
 
-    procedure copyFrom (const aabb: AABB2D); inline;
-    procedure setDims (x0, y0, x1, y1: Float); inline;
+    procedure copyFrom (constref aabb: AABB2D); inline;
+    procedure setDims (x0, y0, x1, y1: TreeNumber); inline;
 
-    procedure setMergeTwo (const aabb0, aabb1: AABB2D); inline;
+    procedure setMergeTwo (constref aabb0, aabb1: AABB2D); inline;
 
-    function volume (): Float; inline;
+    function volume (): TreeNumber; inline;
 
-    procedure merge (const aabb: AABB2D); inline;
+    procedure merge (constref aabb: AABB2D); inline;
 
     // return true if the current AABB contains the AABB given in parameter
-    function contains (const aabb: AABB2D): Boolean; inline; overload;
-    function contains (ax, ay: Float): Boolean; inline; overload;
+    function contains (constref aabb: AABB2D): Boolean; inline; overload;
+    function contains (ax, ay: TreeNumber): Boolean; inline; overload;
 
     // return true if the current AABB is overlapping with the AABB in parameter
     // two AABBs overlap if they overlap in the two axes at the same time
-    function overlaps (const aabb: AABB2D): Boolean; inline; overload;
+    function overlaps (constref aabb: AABB2D): Boolean; inline; overload;
 
     // ray direction must be normalized
-    function intersects (const ray: Ray2D; tmino: PFloat=nil; tmaxo: PFloat=nil): Boolean; overload;
-    function intersects (ax, ay, bx, by: Float): Boolean; inline; overload;
+    function intersects (constref ray: Ray2D; tmino: PSingle=nil; tmaxo: PSingle=nil): Boolean; overload;
+    function intersects (ax, ay, bx, by: Single): Boolean; inline; overload;
 
     property valid: Boolean read getvalid;
-    property centerX: Float read getcenterX;
-    property centerY: Float read getcenterY;
-    property extentX: Float read getextentX;
-    property extentY: Float read getextentY;
+    property centerX: TreeNumber read getcenterX;
+    property centerY: TreeNumber read getcenterY;
+    property extentX: TreeNumber read getextentX;
+    property extentY: TreeNumber read getextentY;
   end;
 
 
@@ -132,7 +133,10 @@ type
 // ////////////////////////////////////////////////////////////////////////// //
 // Dynamic AABB Tree: can be used to speed up broad phase in various engines
 type
-  TDynAABBTree = class(TObject)
+  generic TDynAABBTreeBase<ITP> = class(TObject)
+  public
+    type TTreeFlesh = ITP;
+
   private
     type
       PTreeNode = ^TTreeNode;
@@ -147,33 +151,61 @@ type
         //nextNodeId: Integer;
         // a node is either a leaf (has data) or is an internal node (has children)
         children: array [0..1] of Integer; // left and right child of the node (children[0] = left child)
-        //TODO: `flesh` can be united with `children`
-        flesh: TTreeFlesh;
         // height of the node in the tree (-1 for free nodes)
         height: SmallInt;
         // fat axis aligned bounding box (AABB) corresponding to the node
         aabb: AABB2D;
+        //TODO: `flesh` can be united with `children`
+        flesh: TTreeFlesh;
+        fleshX, fleshY: TreeNumber;
+        tag: Integer; // just a user-defined tag
       public
         // return true if the node is a leaf of the tree
         procedure clear (); inline;
         function leaf (): Boolean; inline;
-        function free (): Boolean; inline;
+        function isfree (): Boolean; inline;
         property nextNodeId: Integer read parentId write parentId;
         //property flesh: Integer read children[0] write children[0];
+
+        procedure dumpToLog ();
       end;
 
-      TVisitCheckerCB = function (node: PTreeNode): Boolean is nested;
-      TVisitVisitorCB = function (abody: TTreeFlesh): Boolean is nested;
+      TVisitCheckerCB = function (node: PTreeNode): Boolean of object;
+      //TVisitVisitorCB = function (abody: TTreeFlesh; atag: Integer): Boolean is nested;
+
+    const ModeNoChecks = 0;
+    const ModeAABB = 1;
+    const ModePoint = 2;
 
   public
     // return `true` to stop
-    type TForEachLeafCB = function (abody: TTreeFlesh; const aabb: AABB2D): Boolean is nested; // WARNING! don't modify AABB here!
+    type TForEachLeafCB = function (abody: TTreeFlesh; constref aabb: AABB2D): Boolean is nested; // WARNING! don't modify AABB here!
 
   public
     // in the broad-phase collision detection (dynamic AABB tree), the AABBs are
     // also inflated in direction of the linear motion of the body by mutliplying the
     // followin constant with the linear velocity and the elapsed time between two frames
+    {$IFDEF aabbtree_use_floats}
     const LinearMotionGapMultiplier = 1.7;
+    {$ELSE}
+    const LinearMotionGapMultiplier = 17; // *10
+    {$ENDIF}
+
+  public
+    // called when a overlapping node has been found during the call to forEachAABBOverlap()
+    // return `true` to stop
+    type TQueryOverlapCB = function (abody: TTreeFlesh; atag: Integer): Boolean is nested;
+    type TSegQueryCallback = function (abody: TTreeFlesh; ax, ay, bx, by: Single): Single is nested; // return dist from (ax,ay) to abody
+
+    PSegmentQueryResult = ^TSegmentQueryResult;
+    TSegmentQueryResult = record
+      dist: Single; // <0: nothing was hit
+      flesh: TTreeFlesh;
+
+      constructor Create (fuckyoufpc: Boolean);
+      procedure reset (); inline;
+      function valid (): Boolean; inline;
+    end;
 
   private
     mNodes: array of TTreeNode; // nodes of the tree
@@ -184,7 +216,25 @@ type
 
     // extra AABB Gap used to allow the collision shape to move a little bit
     // without triggering a large modification of the tree which can be costly
-    mExtraGap: Float;
+    mExtraGap: TreeNumber;
+
+    chkAABB: AABB2D; // for checkers
+    qSRes: PSegmentQueryResult; // for queries
+    // for segment query
+    maxFraction: Single;
+    curax, curay: Single;
+    curbx, curby: Single;
+    dirx, diry: Single;
+    sqcb: TSegQueryCallback;
+    vstack: array of Integer; // for `visit()`
+    vstused: Integer; // to support recursive queries
+
+    function checkerAABB (node: PTreeNode): Boolean;
+    function checkerPoint (node: PTreeNode): Boolean;
+    function checkerRay (node: PTreeNode): Boolean;
+    function visitorRay (flesh: TTreeFlesh; tag: Integer): Boolean;
+
+    type TQueryOverlapDg = function (abody: TTreeFlesh; atag: Integer): Boolean of object;
 
   private
     function allocateNode (): Integer;
@@ -193,51 +243,42 @@ type
     procedure removeLeafNode (nodeId: Integer);
     function balanceSubTreeAtNode (nodeId: Integer): Integer;
     function computeHeight (nodeId: Integer): Integer;
-    function insertObjectInternal (var aabb: AABB2D; staticObject: Boolean): Integer;
+    function insertObjectInternal (constref aabb: AABB2D; staticObject: Boolean): Integer;
     procedure setup ();
-    function visit (checker: TVisitCheckerCB; visitor: TVisitVisitorCB): Integer;
+    function visit (constref caabb: AABB2D; mode: Integer; checker: TVisitCheckerCB; visitor: TQueryOverlapCB; visdg: TQueryOverlapDg; tagmask: Integer): Integer;
+
+    function forEachNode (nodeId: Integer; dg: TForEachLeafCB): Boolean;
 
   public
     {$IFDEF aabbtree_query_count}
-    nodesVisited, nodesDeepVisited: Integer;
+    mNodesVisited, mNodesDeepVisited: Integer;
     {$ENDIF}
 
   public
-    // called when a overlapping node has been found during the call to forEachAABBOverlap()
-    // return `true` to stop
-    type TQueryOverlapCB = function (abody: TTreeFlesh): Boolean is nested;
-    type TSegQueryCallback = function (abody: TTreeFlesh; ax, ay, bx, by: Float): Float is nested; // return dist from (ax,ay) to abody
-
-    TSegmentQueryResult = record
-      dist: Float; // <0: nothing was hit
-      flesh: TTreeFlesh;
-
-      procedure reset (); inline;
-      function valid (): Boolean; inline;
-    end;
-
-  public
-    constructor Create (extraAABBGap: Float=0.0);
+    constructor Create (extraAABBGap: TreeNumber=0);
     destructor Destroy (); override;
 
     // clear all the nodes and reset the tree
     procedure reset ();
 
     function forEachLeaf (dg: TForEachLeafCB): Boolean; // WARNING! don't modify AABB/tree here!
-    procedure getRootAABB (var aabb: AABB2D);
+    procedure getRootAABB (out aabb: AABB2D);
 
     function isValidId (id: Integer): Boolean; inline;
     function getNodeObjectId (nodeid: Integer): TTreeFlesh; inline;
-    procedure getNodeFatAABB (var aabb: AABB2D; nodeid: Integer); inline;
+    procedure getNodeFatAABB (out aabb: AABB2D; nodeid: Integer); inline;
+
+    // returns `false` if nodeid is not leaf
+    function getNodeXY (nodeid: Integer; out x, y: Integer): Boolean; inline;
 
     // return `false` for invalid flesh
-    function getFleshAABB (var aabb: AABB2D; flesh: TTreeFlesh): Boolean; virtual; abstract;
+    function getFleshAABB (out aabb: AABB2D; flesh: TTreeFlesh; tag: Integer): Boolean; virtual; abstract;
 
     // insert an object into the tree
     // this method creates a new leaf node in the tree and returns the id of the corresponding node or -1 on error
     // AABB for static object will not be "fat" (simple optimization)
     // WARNING! inserting the same object several times *WILL* break everything!
-    function insertObject (flesh: TTreeFlesh; staticObject: Boolean=false): Integer;
+    function insertObject (flesh: TTreeFlesh; tag: Integer=-1; staticObject: Boolean=false): Integer;
 
     // remove an object from the tree
     // WARNING: ids of removed objects can be reused on later insertions!
@@ -258,20 +299,35 @@ type
      *
      * return `true` if the tree was modified.
      *)
-    function updateObject (nodeId: Integer; dispX, dispY: Float; forceReinsert: Boolean=false): Boolean;
+    function updateObject (nodeId: Integer; dispX, dispY: TreeNumber; forceReinsert: Boolean=false): Boolean; overload;
+    function updateObject (nodeId: Integer; forceReinsert: Boolean=false): Boolean; overload;
 
-    procedure aabbQuery (ax, ay, aw, ah: Float; cb: TQueryOverlapCB);
-    function pointQuery (ax, ay: Float; cb: TQueryOverlapCB): TTreeFlesh;
-    function segmentQuery (var qr: TSegmentQueryResult; ax, ay, bx, by: Float; cb: TSegQueryCallback): Boolean;
+    function aabbQuery (ax, ay, aw, ah: TreeNumber; cb: TQueryOverlapCB; tagmask: Integer=-1): TTreeFlesh;
+    function pointQuery (ax, ay: TreeNumber; cb: TQueryOverlapCB; tagmask: Integer=-1): TTreeFlesh;
+    function segmentQuery (out qr: TSegmentQueryResult; ax, ay, bx, by: TreeNumber; cb: TSegQueryCallback; tagmask: Integer=-1): Boolean;
 
     function computeTreeHeight (): Integer; // compute the height of the tree
 
-    property extraGap: Float read mExtraGap write mExtraGap;
+    property extraGap: TreeNumber read mExtraGap write mExtraGap;
     property nodeCount: Integer read mNodeCount;
     property nodeAlloced: Integer read mAllocCount;
+    {$IFDEF aabbtree_query_count}
+    property nodesVisited: Integer read mNodesVisited;
+    property nodesDeepVisited: Integer read mNodesDeepVisited;
+    {$ELSE}
+    const nodesVisited = 0;
+    const nodesDeepVisited = 0;
+    {$ENDIF}
   end;
 
 
+function dtMinI (a, b: Integer): Integer; inline;
+function dtMaxI (a, b: Integer): Integer; inline;
+
+function dtMinF (a, b: TreeNumber): TreeNumber; inline;
+function dtMaxF (a, b: TreeNumber): TreeNumber; inline;
+
+
 implementation
 
 uses
@@ -279,20 +335,20 @@ uses
 
 
 // ////////////////////////////////////////////////////////////////////////// //
-function minI (a, b: Integer): Integer; inline; begin if (a < b) then result := a else result := b; end;
-function maxI (a, b: Integer): Integer; inline; begin if (a > b) then result := a else result := b; end;
+function dtMinI (a, b: Integer): Integer; inline; begin if (a < b) then result := a else result := b; end;
+function dtMaxI (a, b: Integer): Integer; inline; begin if (a > b) then result := a else result := b; end;
 
-function minF (a, b: Float): Float; inline; begin if (a < b) then result := a else result := b; end;
-function maxF (a, b: Float): Float; inline; begin if (a > b) then result := a else result := b; end;
+function dtMinF (a, b: TreeNumber): TreeNumber; inline; begin if (a < b) then result := a else result := b; end;
+function dtMaxF (a, b: TreeNumber): TreeNumber; inline; begin if (a > b) then result := a else result := b; end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
-constructor Ray2D.Create (ax, ay: Float; aangle: Float); begin setXYAngle(ax, ay, aangle); end;
-constructor Ray2D.Create (ax0, ay0, ax1, ay1: Float); begin setX0Y0X1Y1(ax0, ay0, ax1, ay1); end;
-constructor Ray2D.Create (const aray: Ray2D); overload; begin copyFrom(aray); end;
+constructor Ray2D.Create (ax, ay: Single; aangle: Single); begin setXYAngle(ax, ay, aangle); end;
+constructor Ray2D.Create (ax0, ay0, ax1, ay1: Single); begin setX0Y0X1Y1(ax0, ay0, ax1, ay1); end;
+constructor Ray2D.Create (constref aray: Ray2D); overload; begin copyFrom(aray); end;
 
 
-procedure Ray2D.copyFrom (const aray: Ray2D); inline;
+procedure Ray2D.copyFrom (constref aray: Ray2D); inline;
 begin
   origX := aray.origX;
   origY := aray.origY;
@@ -302,14 +358,14 @@ end;
 
 procedure Ray2D.normalizeDir (); inline;
 var
-  invlen: Float;
+  invlen: Single;
 begin
   invlen := 1.0/sqrt(dirX*dirX+dirY*dirY);
   dirX *= invlen;
   dirY *= invlen;
 end;
 
-procedure Ray2D.setXYAngle (ax, ay: Float; aangle: Float); inline;
+procedure Ray2D.setXYAngle (ax, ay: Single; aangle: Single); inline;
 begin
   origX := ax;
   origY := ay;
@@ -317,7 +373,7 @@ begin
   dirY := sin(aangle);
 end;
 
-procedure Ray2D.setX0Y0X1Y1 (ax0, ay0, ax1, ay1: Float); inline;
+procedure Ray2D.setX0Y0X1Y1 (ax0, ay0, ax1, ay1: Single); inline;
 begin
   origX := ax0;
   origY := ay0;
@@ -328,72 +384,103 @@ end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
-constructor AABB2D.Create (x0, y0, x1, y1: Float); overload;
+constructor AABB2D.Create (x0, y0, x1, y1: TreeNumber); overload;
 begin
   setDims(x0, y0, x1, y1);
 end;
 
-constructor AABB2D.Create (const aabb: AABB2D); overload;
+constructor AABB2D.Create (constref aabb: AABB2D); overload;
 begin
   copyFrom(aabb);
 end;
 
-constructor AABB2D.Create (const aabb0, aabb1: AABB2D); overload;
+constructor AABB2D.Create (constref aabb0, aabb1: AABB2D); overload;
 begin
   setMergeTwo(aabb0, aabb1);
 end;
 
-function AABB2D.getvalid (): Boolean; inline; begin result := (minX < maxX) and (minY < maxY); end;
+constructor AABB2D.CreateWH (ax, ay, w, h: TreeNumber);
+begin
+  minX := ax;
+  minY := ay;
+  maxX := ax+w-1;
+  maxY := ay+h-1;
+end;
 
-function AABB2D.getcenterX (): Float; inline; begin result := (minX+maxX)/2; end;
-function AABB2D.getcenterY (): Float; inline; begin result := (minY+maxY)/2; end;
-function AABB2D.getextentX (): Float; inline; begin result := (maxX-minX)+1; end;
-function AABB2D.getextentY (): Float; inline; begin result := (maxY-minY)+1; end;
+function AABB2D.getvalid (): Boolean; inline; begin result := (minX <= maxX) and (minY <= maxY); end;
 
+{$IFDEF aabbtree_use_floats}
+function AABB2D.getcenterX (): TreeNumber; inline; begin result := (minX+maxX)/2.0; end;
+function AABB2D.getcenterY (): TreeNumber; inline; begin result := (minY+maxY)/2.0; end;
+{$ELSE}
+function AABB2D.getcenterX (): TreeNumber; inline; begin result := (minX+maxX) div 2; end;
+function AABB2D.getcenterY (): TreeNumber; inline; begin result := (minY+maxY) div 2; end;
+{$ENDIF}
+function AABB2D.getextentX (): TreeNumber; inline; begin result := maxX-minX+1; end;
+function AABB2D.getextentY (): TreeNumber; inline; begin result := maxY-minY+1; end;
 
-procedure AABB2D.copyFrom (const aabb: AABB2D); inline;
+procedure AABB2D.copyFrom (constref aabb: AABB2D); inline;
 begin
   minX := aabb.minX;
   minY := aabb.minY;
   maxX := aabb.maxX;
   maxY := aabb.maxY;
+  {$IF DEFINED(D2F_DEBUG)}
+  if not valid then raise Exception.Create('copyFrom: result is fucked');
+  {$ENDIF}
 end;
 
 
-procedure AABB2D.setDims (x0, y0, x1, y1: Float); inline;
+procedure AABB2D.setDims (x0, y0, x1, y1: TreeNumber); inline;
 begin
-  minX := minF(x0, x1);
-  minY := minF(y0, y1);
-  maxX := maxF(x0, x1);
-  maxY := maxF(y0, y1);
+  minX := dtMinF(x0, x1);
+  minY := dtMinF(y0, y1);
+  maxX := dtMaxF(x0, x1);
+  maxY := dtMaxF(y0, y1);
+  {$IF DEFINED(D2F_DEBUG)}
+  if not valid then raise Exception.Create('setDims: result is fucked');
+  {$ENDIF}
 end;
 
 
-procedure AABB2D.setMergeTwo (const aabb0, aabb1: AABB2D); inline;
+procedure AABB2D.setMergeTwo (constref aabb0, aabb1: AABB2D); inline;
 begin
-  minX := minF(aabb0.minX, aabb1.minX);
-  minY := minF(aabb0.minY, aabb1.minY);
-  maxX := maxF(aabb0.maxX, aabb1.maxX);
-  maxY := maxF(aabb0.maxY, aabb1.maxY);
+  {$IF DEFINED(D2F_DEBUG)}
+  if not aabb0.valid then raise Exception.Create('setMergeTwo: aabb0 is fucked');
+  if not aabb1.valid then raise Exception.Create('setMergeTwo: aabb0 is fucked');
+  {$ENDIF}
+  minX := dtMinF(aabb0.minX, aabb1.minX);
+  minY := dtMinF(aabb0.minY, aabb1.minY);
+  maxX := dtMaxF(aabb0.maxX, aabb1.maxX);
+  maxY := dtMaxF(aabb0.maxY, aabb1.maxY);
+  {$IF DEFINED(D2F_DEBUG)}
+  if not valid then raise Exception.Create('setMergeTwo: result is fucked');
+  {$ENDIF}
 end;
 
 
-function AABB2D.volume (): Float; inline;
+function AABB2D.volume (): TreeNumber; inline;
 begin
-  result := (maxX-minX)*(maxY-minY);
+  result := (maxX-minX+1)*(maxY-minY+1);
 end;
 
 
-procedure AABB2D.merge (const aabb: AABB2D); inline;
+procedure AABB2D.merge (constref aabb: AABB2D); inline;
 begin
-  minX := minF(minX, aabb.minX);
-  minY := minF(minY, aabb.minY);
-  maxX := maxF(maxX, aabb.maxX);
-  maxY := maxF(maxY, aabb.maxY);
+  {$IF DEFINED(D2F_DEBUG)}
+  if not aabb.valid then raise Exception.Create('merge: aabb is fucked');
+  {$ENDIF}
+  minX := dtMinF(minX, aabb.minX);
+  minY := dtMinF(minY, aabb.minY);
+  maxX := dtMaxF(maxX, aabb.maxX);
+  maxY := dtMaxF(maxY, aabb.maxY);
+  {$IF DEFINED(D2F_DEBUG)}
+  if not valid then raise Exception.Create('setMergeTwo: result is fucked');
+  {$ENDIF}
 end;
 
 
-function AABB2D.contains (const aabb: AABB2D): Boolean; inline; overload;
+function AABB2D.contains (constref aabb: AABB2D): Boolean; inline; overload;
 begin
   result :=
     (aabb.minX >= minX) and (aabb.minY >= minY) and
@@ -401,13 +488,13 @@ begin
 end;
 
 
-function AABB2D.contains (ax, ay: Float): Boolean; inline; overload;
+function AABB2D.contains (ax, ay: TreeNumber): Boolean; inline; overload;
 begin
   result := (ax >= minX) and (ay >= minY) and (ax <= maxX) and (ay <= maxY);
 end;
 
 
-function AABB2D.overlaps (const aabb: AABB2D): Boolean; inline; overload;
+function AABB2D.overlaps (constref aabb: AABB2D): Boolean; inline; overload;
 begin
   result := false;
   // exit with no intersection if found separated along any axis
@@ -419,10 +506,10 @@ end;
 
 // something to consider here is that 0 * inf =nan which occurs when the ray starts exactly on the edge of a box
 // https://tavianator.com/fast-branchless-raybounding-box-intersections-part-2-nans/
-function AABB2D.intersects (const ray: Ray2D; tmino: PFloat=nil; tmaxo: PFloat=nil): Boolean; overload;
+function AABB2D.intersects (constref ray: Ray2D; tmino: PSingle=nil; tmaxo: PSingle=nil): Boolean; overload;
 var
-  dinv, t1, t2, tmp: Float;
-  tmin, tmax: Float;
+  dinv, t1, t2, tmp: Single;
+  tmin, tmax: Single;
 begin
   // ok with coplanars
   tmin := -1.0e100;
@@ -464,9 +551,9 @@ begin
   end;
 end;
 
-function AABB2D.intersects (ax, ay, bx, by: Float): Boolean; inline; overload;
+function AABB2D.intersects (ax, ay, bx, by: Single): Boolean; inline; overload;
 var
-  tmin: Float;
+  tmin: Single;
   ray: Ray2D;
 begin
   result := true;
@@ -484,32 +571,40 @@ end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
-procedure TDynAABBTree.TSegmentQueryResult.reset (); inline; begin dist := -1; flesh := nil; end;
-function TDynAABBTree.TSegmentQueryResult.valid (): Boolean; inline; begin result := (dist >= 0) and (flesh <> nil); end;
+constructor TDynAABBTreeBase.TSegmentQueryResult.Create (fuckyoufpc: Boolean); begin dist := -1; flesh := Default(ITP); end;
+procedure TDynAABBTreeBase.TSegmentQueryResult.reset (); inline; begin dist := -1; flesh := Default(ITP); end;
+function TDynAABBTreeBase.TSegmentQueryResult.valid (): Boolean; inline; begin result := (dist >= 0) and (flesh <> Default(ITP)); end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
-function TDynAABBTree.TTreeNode.leaf (): Boolean; inline; begin result := (height = 0); end;
-function TDynAABBTree.TTreeNode.free (): Boolean; inline; begin result := (height = -1); end;
+function TDynAABBTreeBase.TTreeNode.leaf (): Boolean; inline; begin result := (height = 0); end;
+function TDynAABBTreeBase.TTreeNode.isfree (): Boolean; inline; begin result := (height = -1); end;
 
-procedure TDynAABBTree.TTreeNode.clear (); inline;
+procedure TDynAABBTreeBase.TTreeNode.clear (); inline;
 begin
   parentId := 0;
   children[0] := 0;
   children[1] := 0;
-  flesh := nil;
+  flesh := Default(ITP);
+  tag := 0;
   height := 0;
-  //aabb.setX0Y0X1Y1(0, 0, 0, 0);
   aabb.minX := 0;
   aabb.minY := 0;
-  aabb.maxX := -1;
-  aabb.maxY := -1;
+  aabb.maxX := 0;
+  aabb.maxY := 0;
+end;
+
+procedure TDynAABBTreeBase.TTreeNode.dumpToLog ();
+begin
+  e_WriteLog(Format('NODE: parentId=%d; children=[%d,%d]; height=%d; tag=%d; fleshX=%d; fleshY=%d; aabb=(%d,%d)-(%d,%d)',
+    [parentId, children[0], children[1], Integer(height), tag, fleshX, fleshY, aabb.minX, aabb.minY, aabb.maxX, aabb.maxY]),
+    MSG_NOTIFY);
 end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
 // allocate and return a node to use in the tree
-function TDynAABBTree.allocateNode (): Integer;
+function TDynAABBTreeBase.allocateNode (): Integer;
 var
   i, newsz, freeNodeId: Integer;
   node: PTreeNode;
@@ -519,22 +614,21 @@ begin
   begin
     {$IFDEF aabbtree_many_asserts}assert(mNodeCount = mAllocCount);{$ENDIF}
     // allocate more nodes in the tree
-    if (mAllocCount < 8192) then newsz := mAllocCount*2 else newsz := mAllocCount+8192;
+    if (mAllocCount <= 16384) then newsz := mAllocCount*2 else newsz := mAllocCount+16384;
     SetLength(mNodes, newsz);
     mAllocCount := newsz;
     // initialize the allocated nodes
-    for i := mNodeCount to mAllocCount-2 do
+    for i := mNodeCount to mAllocCount-1 do
     begin
       mNodes[i].nextNodeId := i+1;
       mNodes[i].height := -1;
     end;
     mNodes[mAllocCount-1].nextNodeId := TTreeNode.NullTreeNode;
-    mNodes[mAllocCount-1].height := -1;
     mFreeNodeId := mNodeCount;
   end;
   // get the next free node
   freeNodeId := mFreeNodeId;
-  {$IFDEF aabbtree_many_asserts}assert((freeNodeId >= mNodeCount) and (freeNodeId < mAllocCount));{$ENDIF}
+  {$IFDEF aabbtree_many_asserts}assert(freeNodeId < mAllocCount);{$ENDIF}
   node := @mNodes[freeNodeId];
   mFreeNodeId := node.nextNodeId;
   node.clear();
@@ -542,32 +636,37 @@ begin
   node.height := 0;
   Inc(mNodeCount);
   result := freeNodeId;
+
+  //e_WriteLog(Format('tree: allocated node #%d', [result]), MSG_NOTIFY);
 end;
 
 
 // release a node
-procedure TDynAABBTree.releaseNode (nodeId: Integer);
+procedure TDynAABBTreeBase.releaseNode (nodeId: Integer);
 begin
   {$IFDEF aabbtree_many_asserts}assert(mNodeCount > 0);{$ENDIF}
   {$IFDEF aabbtree_many_asserts}assert((nodeId >= 0) and (nodeId < mAllocCount));{$ENDIF}
   {$IFDEF aabbtree_many_asserts}assert(mNodes[nodeId].height >= 0);{$ENDIF}
   mNodes[nodeId].nextNodeId := mFreeNodeId;
   mNodes[nodeId].height := -1;
+  mNodes[nodeId].flesh := Default(ITP);
   mFreeNodeId := nodeId;
   Dec(mNodeCount);
+
+  //e_WriteLog(Format('tree: released node #%d', [nodeId]), MSG_NOTIFY);
 end;
 
 
 // insert a leaf node in the tree
 // the process of inserting a new leaf node in the dynamic tree is described in the book "Introduction to Game Physics with Box2D" by Ian Parberry
-procedure TDynAABBTree.insertLeafNode (nodeId: Integer);
+procedure TDynAABBTreeBase.insertLeafNode (nodeId: Integer);
 var
   newNodeAABB, mergedAABBs, currentAndLeftAABB, currentAndRightAABB: AABB2D;
   currentNodeId: Integer;
   leftChild, rightChild, siblingNode: Integer;
   oldParentNode, newParentNode: Integer;
-  volumeAABB, mergedVolume: Float;
-  costS, costI, costLeft, costRight: Float;
+  volumeAABB, mergedVolume: TreeNumber;
+  costS, costI, costLeft, costRight: TreeNumber;
 begin
   // if the tree is empty
   if (mRootNodeId = TTreeNode.NullTreeNode) then
@@ -580,7 +679,7 @@ begin
   {$IFDEF aabbtree_many_asserts}assert(mRootNodeId <> TTreeNode.NullTreeNode);{$ENDIF}
 
   // find the best sibling node for the new node
-  newNodeAABB := mNodes[nodeId].aabb;
+  newNodeAABB := AABB2D.Create(mNodes[nodeId].aabb);
   currentNodeId := mRootNodeId;
   while not mNodes[currentNodeId].leaf do
   begin
@@ -593,20 +692,20 @@ begin
     mergedVolume := mergedAABBs.volume;
 
     // compute the cost of making the current node the sibling of the new node
-    costS := 2.0*mergedVolume;
+    costS := 2*mergedVolume;
 
     // compute the minimum cost of pushing the new node further down the tree (inheritance cost)
-    costI := 2.0*(mergedVolume-volumeAABB);
+    costI := 2*(mergedVolume-volumeAABB);
 
     // compute the cost of descending into the left child
     currentAndLeftAABB := AABB2D.Create(newNodeAABB, mNodes[leftChild].aabb);
     costLeft := currentAndLeftAABB.volume+costI;
-    if not mNodes[leftChild].leaf then costLeft := costLeft-mNodes[leftChild].aabb.volume;
+    if not mNodes[leftChild].leaf then costLeft -= mNodes[leftChild].aabb.volume;
 
     // compute the cost of descending into the right child
     currentAndRightAABB := AABB2D.Create(newNodeAABB, mNodes[rightChild].aabb);
     costRight := currentAndRightAABB.volume+costI;
-    if not mNodes[rightChild].leaf then costRight := costRight-mNodes[rightChild].aabb.volume;
+    if not mNodes[rightChild].leaf then costRight -= mNodes[rightChild].aabb.volume;
 
     // if the cost of making the current node a sibling of the new node is smaller than the cost of going down into the left or right child
     if (costS < costLeft) and (costS < costRight) then break;
@@ -669,7 +768,7 @@ begin
     {$IFDEF aabbtree_many_asserts}assert(rightChild <> TTreeNode.NullTreeNode);{$ENDIF}
 
     // recompute the height of the node in the tree
-    mNodes[currentNodeId].height := maxI(mNodes[leftChild].height, mNodes[rightChild].height)+1;
+    mNodes[currentNodeId].height := dtMaxI(mNodes[leftChild].height, mNodes[rightChild].height)+1;
     {$IFDEF aabbtree_many_asserts}assert(mNodes[currentNodeId].height > 0);{$ENDIF}
 
     // recompute the AABB of the node
@@ -683,7 +782,7 @@ end;
 
 
 // remove a leaf node from the tree
-procedure TDynAABBTree.removeLeafNode (nodeId: Integer);
+procedure TDynAABBTreeBase.removeLeafNode (nodeId: Integer);
 var
   currentNodeId, parentNodeId, grandParentNodeId, siblingNodeId: Integer;
   leftChildId, rightChildId: Integer;
@@ -737,7 +836,7 @@ begin
 
       // recompute the AABB and the height of the current node
       mNodes[currentNodeId].aabb.setMergeTwo(mNodes[leftChildId].aabb, mNodes[rightChildId].aabb);
-      mNodes[currentNodeId].height := maxI(mNodes[leftChildId].height, mNodes[rightChildId].height)+1;
+      mNodes[currentNodeId].height := dtMaxI(mNodes[leftChildId].height, mNodes[rightChildId].height)+1;
       {$IFDEF aabbtree_many_asserts}assert(mNodes[currentNodeId].height > 0);{$ENDIF}
 
       currentNodeId := mNodes[currentNodeId].parentId;
@@ -756,7 +855,7 @@ end;
 // balance the sub-tree of a given node using left or right rotations
 // the rotation schemes are described in the book "Introduction to Game Physics with Box2D" by Ian Parberry
 // this method returns the new root node id
-function TDynAABBTree.balanceSubTreeAtNode (nodeId: Integer): Integer;
+function TDynAABBTreeBase.balanceSubTreeAtNode (nodeId: Integer): Integer;
 var
   nodeA, nodeB, nodeC, nodeF, nodeG: PTreeNode;
   nodeBId, nodeCId, nodeFId, nodeGId: Integer;
@@ -781,7 +880,7 @@ begin
   balanceFactor := nodeC.height-nodeB.height;
 
   // if the right node C is 2 higher than left node B
-  if (balanceFactor > 1.0) then
+  if (balanceFactor > 1) then
   begin
     {$IFDEF aabbtree_many_asserts}assert(not nodeC.leaf);{$ENDIF}
 
@@ -828,8 +927,8 @@ begin
       nodeC.aabb.setMergeTwo(nodeA.aabb, nodeF.aabb);
 
       // recompute the height of node A and C
-      nodeA.height := maxI(nodeB.height, nodeG.height)+1;
-      nodeC.height := maxI(nodeA.height, nodeF.height)+1;
+      nodeA.height := dtMaxI(nodeB.height, nodeG.height)+1;
+      nodeC.height := dtMaxI(nodeA.height, nodeF.height)+1;
       {$IFDEF aabbtree_many_asserts}assert(nodeA.height > 0);{$ENDIF}
       {$IFDEF aabbtree_many_asserts}assert(nodeC.height > 0);{$ENDIF}
     end
@@ -845,8 +944,8 @@ begin
       nodeC.aabb.setMergeTwo(nodeA.aabb, nodeG.aabb);
 
       // recompute the height of node A and C
-      nodeA.height := maxI(nodeB.height, nodeF.height)+1;
-      nodeC.height := maxI(nodeA.height, nodeG.height)+1;
+      nodeA.height := dtMaxI(nodeB.height, nodeF.height)+1;
+      nodeC.height := dtMaxI(nodeA.height, nodeG.height)+1;
       {$IFDEF aabbtree_many_asserts}assert(nodeA.height > 0);{$ENDIF}
       {$IFDEF aabbtree_many_asserts}assert(nodeC.height > 0);{$ENDIF}
     end;
@@ -904,8 +1003,8 @@ begin
       nodeB.aabb.setMergeTwo(nodeA.aabb, nodeF.aabb);
 
       // recompute the height of node A and B
-      nodeA.height := maxI(nodeC.height, nodeG.height)+1;
-      nodeB.height := maxI(nodeA.height, nodeF.height)+1;
+      nodeA.height := dtMaxI(nodeC.height, nodeG.height)+1;
+      nodeB.height := dtMaxI(nodeA.height, nodeF.height)+1;
       {$IFDEF aabbtree_many_asserts}assert(nodeA.height > 0);{$ENDIF}
       {$IFDEF aabbtree_many_asserts}assert(nodeB.height > 0);{$ENDIF}
     end
@@ -921,8 +1020,8 @@ begin
       nodeB.aabb.setMergeTwo(nodeA.aabb, nodeG.aabb);
 
       // recompute the height of node A and B
-      nodeA.height := maxI(nodeC.height, nodeF.height)+1;
-      nodeB.height := maxI(nodeA.height, nodeG.height)+1;
+      nodeA.height := dtMaxI(nodeC.height, nodeF.height)+1;
+      nodeB.height := dtMaxI(nodeA.height, nodeG.height)+1;
       {$IFDEF aabbtree_many_asserts}assert(nodeA.height > 0);{$ENDIF}
       {$IFDEF aabbtree_many_asserts}assert(nodeB.height > 0);{$ENDIF}
     end;
@@ -938,7 +1037,7 @@ end;
 
 
 // compute the height of a given node in the tree
-function TDynAABBTree.computeHeight (nodeId: Integer): Integer;
+function TDynAABBTreeBase.computeHeight (nodeId: Integer): Integer;
 var
   node: PTreeNode;
   leftHeight, rightHeight: Integer;
@@ -954,36 +1053,39 @@ begin
   rightHeight := computeHeight(node.children[TTreeNode.Right]);
 
   // return the height of the node
-  result := 1+maxI(leftHeight, rightHeight);
+  result := 1+dtMaxI(leftHeight, rightHeight);
 end;
 
 
 // internally add an object into the tree
-function TDynAABBTree.insertObjectInternal (var aabb: AABB2D; staticObject: Boolean): Integer;
+function TDynAABBTreeBase.insertObjectInternal (constref aabb: AABB2D; staticObject: Boolean): Integer;
 var
   nodeId: Integer;
+  node: PTreeNode;
 begin
   // get the next available node (or allocate new ones if necessary)
   nodeId := allocateNode();
 
+  node := @mNodes[nodeId];
+
   // create the fat aabb to use in the tree
-  mNodes[nodeId].aabb := aabb;
+  node.aabb := AABB2D.Create(aabb);
   if (not staticObject) then
   begin
-    mNodes[nodeId].aabb.minX -= mExtraGap;
-    mNodes[nodeId].aabb.minY -= mExtraGap;
-    mNodes[nodeId].aabb.maxX += mExtraGap;
-    mNodes[nodeId].aabb.maxY += mExtraGap;
+    node.aabb.minX -= mExtraGap;
+    node.aabb.minY -= mExtraGap;
+    node.aabb.maxX += mExtraGap;
+    node.aabb.maxY += mExtraGap;
   end;
 
   // set the height of the node in the tree
-  mNodes[nodeId].height := 0;
+  node.height := 0;
 
   // insert the new leaf node in the tree
   insertLeafNode(nodeId);
-  {$IFDEF aabbtree_many_asserts}assert(mNodes[nodeId].leaf);{$ENDIF}
 
-  {$IFDEF aabbtree_many_asserts}assert(nodeId >= 0);{$ENDIF}
+  {$IFDEF aabbtree_many_asserts}node := @mNodes[nodeId];{$ENDIF}
+  {$IFDEF aabbtree_many_asserts}assert(node.leaf);{$ENDIF}
 
   // return the id of the node
   result := nodeId;
@@ -991,247 +1093,294 @@ end;
 
 
 // initialize the tree
-procedure TDynAABBTree.setup ();
+procedure TDynAABBTreeBase.setup ();
 var
   i: Integer;
 begin
   mRootNodeId := TTreeNode.NullTreeNode;
   mNodeCount := 0;
   mAllocCount := 8192;
+  vstused := 0;
 
   SetLength(mNodes, mAllocCount);
   //memset(mNodes, 0, mAllocCount*TTreeNode.sizeof);
   for i := 0 to mAllocCount-1 do mNodes[i].clear();
 
   // initialize the allocated nodes
-  for i := 0 to mAllocCount-2 do
+  for i := 0 to mAllocCount-1 do
   begin
     mNodes[i].nextNodeId := i+1;
     mNodes[i].height := -1;
   end;
   mNodes[mAllocCount-1].nextNodeId := TTreeNode.NullTreeNode;
-  mNodes[mAllocCount-1].height := -1;
   mFreeNodeId := 0;
 end;
 
 
 // also, checks if the tree structure is valid (for debugging purpose)
-function TDynAABBTree.forEachLeaf (dg: TForEachLeafCB): Boolean;
-  function forEachNode (nodeId: Integer): Boolean;
-  var
-    pNode: PTreeNode;
-    leftChild, rightChild, height: Integer;
-    aabb: AABB2D;
+function TDynAABBTreeBase.forEachNode (nodeId: Integer; dg: TForEachLeafCB): Boolean;
+var
+  pNode: PTreeNode;
+  leftChild, rightChild, height: Integer;
+  aabb: AABB2D;
+begin
+  result := false;
+  if (nodeId = TTreeNode.NullTreeNode) then exit;
+  // if it is the root
+  if (nodeId = mRootNodeId) then assert(mNodes[nodeId].parentId = TTreeNode.NullTreeNode);
+  // get the children nodes
+  pNode := @mNodes[nodeId];
+  assert(pNode.height >= 0);
+  if (not pNode.aabb.valid) then
   begin
-    result := false;
-    if (nodeId = TTreeNode.NullTreeNode) then exit;
-    // if it is the root
-    if (nodeId = mRootNodeId) then assert(mNodes[nodeId].parentId = TTreeNode.NullTreeNode);
-    // get the children nodes
-    pNode := @mNodes[nodeId];
-    assert(pNode.height >= 0);
-    e_WriteLog(Format('AABB:(%f,%f)-(%f,%f); volume=%f; valid=%d', [pNode.aabb.minX, pNode.aabb.minY, pNode.aabb.maxX, pNode.aabb.maxY, pNode.aabb.volume, Integer(pNode.aabb.valid)]), MSG_NOTIFY);
-    assert(pNode.aabb.valid);
-    assert(pNode.aabb.volume > 0);
-    // if the current node is a leaf
-    if (pNode.leaf) then
-    begin
-      assert(pNode.height = 0);
-      if assigned(dg) then result := dg(pNode.flesh, pNode.aabb);
-    end
-    else
+    {$IFDEF aabbtree_use_floats}
+    e_WriteLog(Format('AABB:(%f,%f)-(%f,%f); volume=%f; valid=%d; height=%d; leaf=%d', [pNode.aabb.minX, pNode.aabb.minY, pNode.aabb.maxX, pNode.aabb.maxY, pNode.aabb.volume, Integer(pNode.aabb.valid), pNode.height, Integer(pNode.leaf)]), MSG_NOTIFY);
+    {$ELSE}
+    e_WriteLog(Format('AABB:(%d,%d)-(%d,%d); volume=%d; valid=%d; height=%d; leaf=%d', [pNode.aabb.minX, pNode.aabb.minY, pNode.aabb.maxX, pNode.aabb.maxY, pNode.aabb.volume, Integer(pNode.aabb.valid), pNode.height, Integer(pNode.leaf)]), MSG_NOTIFY);
+    {$ENDIF}
+    if pNode.leaf then
     begin
-      leftChild := pNode.children[TTreeNode.Left];
-      rightChild := pNode.children[TTreeNode.Right];
-      // check that the children node Ids are valid
-      assert((0 <= leftChild) and (leftChild < mAllocCount));
-      assert((0 <= rightChild) and (rightChild < mAllocCount));
-      // check that the children nodes have the correct parent node
-      assert(mNodes[leftChild].parentId = nodeId);
-      assert(mNodes[rightChild].parentId = nodeId);
-      // check the height of node
-      height := 1+maxI(mNodes[leftChild].height, mNodes[rightChild].height);
-      assert(mNodes[nodeId].height = height);
-      // check the AABB of the node
-      aabb := AABB2D.Create(mNodes[leftChild].aabb, mNodes[rightChild].aabb);
-      assert(aabb.minX = mNodes[nodeId].aabb.minX);
-      assert(aabb.minY = mNodes[nodeId].aabb.minY);
-      assert(aabb.maxX = mNodes[nodeId].aabb.maxX);
-      assert(aabb.maxY = mNodes[nodeId].aabb.maxY);
-      // recursively check the children nodes
-      result := forEachNode(leftChild);
-      if not result then result := forEachNode(rightChild);
+      getFleshAABB(aabb, pNode.flesh, pNode.tag);
+      {$IFDEF aabbtree_use_floats}
+      e_WriteLog(Format('  LEAF AABB:(%f,%f)-(%f,%f); valid=%d; volume=%f', [aabb.minX, aabb.minY, aabb.maxX, aabb.maxY, Integer(aabb.valid), aabb.volume]), MSG_NOTIFY);
+      {$ELSE}
+      e_WriteLog(Format('  LEAF AABB:(%d,%d)-(%d,%d); valid=%d; volume=%d', [aabb.minX, aabb.minY, aabb.maxX, aabb.maxY, Integer(aabb.valid), aabb.volume]), MSG_NOTIFY);
+      {$ENDIF}
     end;
   end;
+  assert(pNode.aabb.valid);
+  assert(pNode.aabb.volume > 0);
+  // if the current node is a leaf
+  if (pNode.leaf) then
+  begin
+    assert(pNode.height = 0);
+    if assigned(dg) then result := dg(pNode.flesh, pNode.aabb);
+  end
+  else
+  begin
+    leftChild := pNode.children[TTreeNode.Left];
+    rightChild := pNode.children[TTreeNode.Right];
+    // check that the children node Ids are valid
+    assert((0 <= leftChild) and (leftChild < mAllocCount));
+    assert((0 <= rightChild) and (rightChild < mAllocCount));
+    // check that the children nodes have the correct parent node
+    assert(mNodes[leftChild].parentId = nodeId);
+    assert(mNodes[rightChild].parentId = nodeId);
+    // check the height of node
+    height := 1+dtMaxI(mNodes[leftChild].height, mNodes[rightChild].height);
+    assert(mNodes[nodeId].height = height);
+    // check the AABB of the node
+    aabb := AABB2D.Create(mNodes[leftChild].aabb, mNodes[rightChild].aabb);
+    assert(aabb.minX = mNodes[nodeId].aabb.minX);
+    assert(aabb.minY = mNodes[nodeId].aabb.minY);
+    assert(aabb.maxX = mNodes[nodeId].aabb.maxX);
+    assert(aabb.maxY = mNodes[nodeId].aabb.maxY);
+    // recursively check the children nodes
+    result := forEachNode(leftChild, dg);
+    if not result then result := forEachNode(rightChild, dg);
+  end;
+end;
+
 
+// also, checks if the tree structure is valid (for debugging purpose)
+function TDynAABBTreeBase.forEachLeaf (dg: TForEachLeafCB): Boolean;
 begin
   // recursively check each node
-  result := forEachNode(mRootNodeId);
+  result := forEachNode(mRootNodeId, dg);
 end;
 
 
 // return `true` from visitor to stop immediately
 // checker should check if this node should be considered to further checking
 // returns tree node if visitor says stop or -1
-function TDynAABBTree.visit (checker: TVisitCheckerCB; visitor: TVisitVisitorCB): Integer;
-var
-  stack: array [0..255] of Integer; // stack with the nodes to visit
-  bigstack: array of Integer = nil;
-  sp: Integer = 0;
-
-  procedure spush (id: Integer);
-  var
-    xsp: Integer;
-  begin
-    if (sp < length(stack)) then
-    begin
-      // use "small stack"
-      stack[sp] := id;
-      Inc(sp);
-    end
-    else
-    begin
-      // use "big stack"
-      xsp := sp-length(stack);
-      if (xsp < length(bigstack)) then
-      begin
-        // reuse
-        bigstack[xsp] := id;
-      end
-      else
-      begin
-        // grow
-        SetLength(bigstack, length(bigstack)+1);
-        bigstack[high(bigstack)] := id;
-      end;
-      Inc(sp);
-    end;
-  end;
-
-  function spop (): Integer;
-  begin
-    assert(sp > 0);
-    if (sp <= length(stack)) then
-    begin
-      // use "small stack"
-      Dec(sp);
-      result := stack[sp];
-    end
-    else
-    begin
-      // use "big stack"
-      Dec(sp);
-      result := bigstack[sp-length(stack)];
-    end;
-  end;
-
+function TDynAABBTreeBase.visit (constref caabb: AABB2D; mode: Integer; checker: TVisitCheckerCB; visitor: TQueryOverlapCB; visdg: TQueryOverlapDg; tagmask: Integer): Integer;
+const
+  StackGran = 1024;
 var
+  oldvstused: Integer;
   nodeId: Integer;
   node: PTreeNode;
+  doNode: Boolean = false;
 begin
   if not assigned(checker) then begin result := -1; exit; end;
-  //if not assigned(visitor) then begin result := -1; exit; end;
-  try
+  //if not assigned(visitor) and not assigned(visdg) then raise Exception.Create('dyntree: empty visitors aren''t supported');
+  oldvstused := vstused;
+  if (vstused+StackGran > Length(vstack)) then SetLength(vstack, vstused+StackGran);
+  //try
     {$IFDEF aabbtree_query_count}
-    nodesVisited := 0;
-    nodesDeepVisited := 0;
+    mNodesVisited := 0;
+    mNodesDeepVisited := 0;
     {$ENDIF}
 
     // start from root node
-    spush(mRootNodeId);
+    // we can't have nested functions in generics, sorry
+    {$IF FALSE}
+      spush(mRootNodeId);
+    {$ELSE}
+      if (vstused >= Length(vstack)) then SetLength(vstack, vstused+StackGran);
+      vstack[vstused] := mRootNodeId;
+      Inc(vstused);
+    {$ENDIF}
 
     // while there are still nodes to visit
-    while (sp > 0) do
+    while (vstused > oldvstused) do
     begin
       // get the next node id to visit
-      nodeId := spop();
+      // we can't have nested functions in generics, sorry
+      {$IF FALSE}
+        nodeId := spop();
+      {$ELSE}
+        Dec(vstused);
+        nodeId := vstack[vstused];
+      {$ENDIF}
       // skip it if it is a nil node
       if (nodeId = TTreeNode.NullTreeNode) then continue;
-      {$IFDEF aabbtree_query_count}Inc(nodesVisited);{$ENDIF}
+      {$IFDEF aabbtree_query_count}Inc(mNodesVisited);{$ENDIF}
       // get the corresponding node
       node := @mNodes[nodeId];
       // should we investigate this node?
-      if (checker(node)) then
+      case mode of
+        ModeNoChecks: doNode := checker(node);
+        ModeAABB:
+          begin
+            //doNode := caabb.overlaps(node.aabb);
+            // this gives small speedup (or not...)
+            // exit with no intersection if found separated along any axis
+                 if (caabb.maxX < node.aabb.minX) or (caabb.minX > node.aabb.maxX) then doNode := false
+            else if (caabb.maxY < node.aabb.minY) or (caabb.minY > node.aabb.maxY) then doNode := false
+            else doNode := true;
+          end;
+        ModePoint:
+          begin
+            //doNode := node.aabb.contains(caabb.minX, caabb.minY);
+            // this gives small speedup
+            doNode := (caabb.minX >= node.aabb.minX) and (caabb.minY >= node.aabb.minY) and (caabb.minX <= node.aabb.maxX) and (caabb.minY <= node.aabb.maxY);
+          end;
+      end;
+      if doNode then
       begin
         // if the node is a leaf
         if (node.leaf) then
         begin
           // call visitor on it
-          {$IFDEF aabbtree_query_count}Inc(nodesDeepVisited);{$ENDIF}
-          if assigned(visitor) then
+          {$IFDEF aabbtree_query_count}Inc(mNodesDeepVisited);{$ENDIF}
+          if (tagmask = -1) or ((node.tag and tagmask) <> 0) then
           begin
-            if (visitor(node.flesh)) then begin result := nodeId; exit; end;
+            if assigned(visitor) then
+            begin
+              if (visitor(node.flesh, node.tag)) then begin result := nodeId; vstused := oldvstused; exit; end;
+            end;
+            if assigned(visdg) then
+            begin
+              if (visdg(node.flesh, node.tag)) then begin result := nodeId; vstused := oldvstused; exit; end;
+            end;
           end;
         end
         else
         begin
           // if the node is not a leaf, we need to visit its children
-          spush(node.children[TTreeNode.Left]);
-          spush(node.children[TTreeNode.Right]);
+          // we can't have nested functions in generics, sorry
+          {$IF FALSE}
+            spush(node.children[TTreeNode.Left]);
+            spush(node.children[TTreeNode.Right]);
+          {$ELSE}
+            if (vstused+2 > Length(vstack)) then SetLength(vstack, vstused+StackGran);
+            vstack[vstused] := node.children[TTreeNode.Left];
+            Inc(vstused);
+            vstack[vstused] := node.children[TTreeNode.Right];
+            Inc(vstused);
+          {$ENDIF}
         end;
       end;
     end;
 
     result := -1; // oops
-  finally
-    bigstack := nil;
-  end;
+    vstused := oldvstused;
+  //finally
+  //  bigstack := nil;
+  //end;
 end;
 
 
 // add `extraAABBGap` to bounding boxes so slight object movement won't cause tree rebuilds
 // extra AABB Gap used to allow the collision shape to move a little bit without triggering a large modification of the tree which can be costly
-constructor TDynAABBTree.Create (extraAABBGap: Float=0.0);
+constructor TDynAABBTreeBase.Create (extraAABBGap: TreeNumber=0);
 begin
   mExtraGap := extraAABBGap;
+  mNodes := nil;
+  SetLength(vstack, 2048);
+  vstused := 0;
   setup();
 end;
 
 
-destructor TDynAABBTree.Destroy ();
+destructor TDynAABBTreeBase.Destroy ();
 begin
   mNodes := nil;
+  vstack := nil;
   inherited;
 end;
 
 
 // clear all the nodes and reset the tree
-procedure TDynAABBTree.reset ();
+procedure TDynAABBTreeBase.reset ();
 begin
   mNodes := nil;
   setup();
 end;
 
 
-function TDynAABBTree.computeTreeHeight (): Integer; begin result := computeHeight(mRootNodeId); end;
+function TDynAABBTreeBase.computeTreeHeight (): Integer; begin result := computeHeight(mRootNodeId); end;
 
 
 // return the root AABB of the tree
-procedure TDynAABBTree.getRootAABB (var aabb: AABB2D);
+procedure TDynAABBTreeBase.getRootAABB (out aabb: AABB2D);
 begin
-  {$IFDEF aabbtree_many_asserts}assert((mRootNodeId >= 0) and (mRootNodeId < mNodeCount));{$ENDIF}
+  {$IFDEF aabbtree_many_asserts}assert((mRootNodeId >= 0) and (mRootNodeId < mAllocCount));{$ENDIF}
   aabb := mNodes[mRootNodeId].aabb;
 end;
 
 
 // does the given id represents a valid object?
 // WARNING: ids of removed objects can be reused on later insertions!
-function TDynAABBTree.isValidId (id: Integer): Boolean;
+function TDynAABBTreeBase.isValidId (id: Integer): Boolean;
 begin
-  result := (id >= 0) and (id < mNodeCount) and (mNodes[id].leaf);
+  result := (id >= 0) and (id < mAllocCount) and (mNodes[id].leaf);
 end;
 
 
 // get object by nodeid; can return nil for invalid ids
-function TDynAABBTree.getNodeObjectId (nodeid: Integer): TTreeFlesh;
+function TDynAABBTreeBase.getNodeObjectId (nodeid: Integer): TTreeFlesh;
 begin
-  if (nodeid >= 0) and (nodeid < mNodeCount) and (mNodes[nodeid].leaf) then result := mNodes[nodeid].flesh else result := nil;
+  if (nodeid >= 0) and (nodeid < mAllocCount) and (mNodes[nodeid].leaf) then result := mNodes[nodeid].flesh else result := Default(ITP);
 end;
 
 // get fat object AABB by nodeid; returns random shit for invalid ids
-procedure TDynAABBTree.getNodeFatAABB (var aabb: AABB2D; nodeid: Integer);
+procedure TDynAABBTreeBase.getNodeFatAABB (out aabb: AABB2D; nodeid: Integer);
 begin
-  if (nodeid >= 0) and (nodeid < mNodeCount) and (not mNodes[nodeid].free) then aabb.copyFrom(mNodes[nodeid].aabb) else aabb.setDims(0, 0, 0, 0);
+  if (nodeid >= 0) and (nodeid < mAllocCount) and (not mNodes[nodeid].isfree) then aabb := AABB2D.Create(mNodes[nodeid].aabb) else aabb := AABB2D.Create(0, 0, 0, 0);
+end;
+
+function TDynAABBTreeBase.getNodeXY (nodeid: Integer; out x, y: Integer): Boolean; inline;
+begin
+  if (nodeid >= 0) and (nodeid < mAllocCount) and (mNodes[nodeid].leaf) then
+  begin
+    result := true;
+    {$IFDEF aabbtree_use_floats}
+    x := round(mNodes[nodeid].fleshX);
+    y := round(mNodes[nodeid].fleshY);
+    {$ELSE}
+    x := mNodes[nodeid].fleshX;
+    y := mNodes[nodeid].fleshY;
+    {$ENDIF}
+  end
+  else
+  begin
+    result := false;
+    x := 0;
+    y := 0;
+    //if (nodeid >= 0) and (nodeid < mAllocCount) then mNodes[nodeid].dumpToLog();
+  end;
 end;
 
 
@@ -1239,79 +1388,138 @@ end;
 // this method creates a new leaf node in the tree and returns the id of the corresponding node or -1 on error
 // AABB for static object will not be "fat" (simple optimization)
 // WARNING! inserting the same object several times *WILL* break everything!
-function TDynAABBTree.insertObject (flesh: TTreeFlesh; staticObject: Boolean=false): Integer;
+function TDynAABBTreeBase.insertObject (flesh: TTreeFlesh; tag: Integer; staticObject: Boolean=false): Integer;
 var
   aabb: AABB2D;
-  nodeId: Integer;
+  nodeId, fx, fy: Integer;
 begin
-  if not getFleshAABB(aabb, flesh) then
+  if not getFleshAABB(aabb, flesh, tag) then
   begin
+    {$IFDEF aabbtree_use_floats}
+    e_WriteLog(Format('trying to insert FUCKED FLESH:(%f,%f)-(%f,%f); volume=%f; valid=%d', [aabb.minX, aabb.minY, aabb.maxX, aabb.maxY, aabb.volume, Integer(aabb.valid)]), MSG_WARNING);
+    {$ELSE}
+    e_WriteLog(Format('trying to insert FUCKED FLESH:(%d,%d)-(%d,%d); volume=%d; valid=%d', [aabb.minX, aabb.minY, aabb.maxX, aabb.maxY, aabb.volume, Integer(aabb.valid)]), MSG_WARNING);
+    {$ENDIF}
+    //raise Exception.Create('trying to insert invalid flesh in dyntree');
+    result := -1;
+    exit;
+  end;
+  if not aabb.valid then
+  begin
+    {$IFDEF aabbtree_use_floats}
     e_WriteLog(Format('trying to insert FUCKED AABB:(%f,%f)-(%f,%f); volume=%f; valid=%d', [aabb.minX, aabb.minY, aabb.maxX, aabb.maxY, aabb.volume, Integer(aabb.valid)]), MSG_WARNING);
+    {$ELSE}
+    e_WriteLog(Format('trying to insert FUCKED AABB:(%d,%d)-(%d,%d); volume=%d; valid=%d', [aabb.minX, aabb.minY, aabb.maxX, aabb.maxY, aabb.volume, Integer(aabb.valid)]), MSG_WARNING);
+    {$ENDIF}
+    raise Exception.Create('trying to insert invalid aabb in dyntree');
     result := -1;
     exit;
   end;
-  e_WriteLog(Format('inserting AABB:(%f,%f)-(%f,%f); volume=%f; valid=%d', [aabb.minX, aabb.minY, aabb.maxX, aabb.maxY, aabb.volume, Integer(aabb.valid)]), MSG_NOTIFY);
+  //e_WriteLog(Format('inserting AABB:(%f,%f)-(%f,%f); volume=%f; valid=%d', [aabb.minX, aabb.minY, aabb.maxX, aabb.maxY, aabb.volume, Integer(aabb.valid)]), MSG_NOTIFY);
+  fx := aabb.minX;
+  fy := aabb.minY;
   nodeId := insertObjectInternal(aabb, staticObject);
   {$IFDEF aabbtree_many_asserts}assert(mNodes[nodeId].leaf);{$ENDIF}
   mNodes[nodeId].flesh := flesh;
+  mNodes[nodeId].tag := tag;
+  mNodes[nodeId].fleshX := fx;
+  mNodes[nodeId].fleshY := fy;
   result := nodeId;
 end;
 
 
 // remove an object from the tree
 // WARNING: ids of removed objects can be reused on later insertions!
-procedure TDynAABBTree.removeObject (nodeId: Integer);
+procedure TDynAABBTreeBase.removeObject (nodeId: Integer);
 begin
-  if (nodeId < 0) or (nodeId >= mNodeCount) or (not mNodes[nodeId].leaf) then raise Exception.Create('invalid node id in TDynAABBTree');
+  if (nodeId < 0) or (nodeId >= mAllocCount) or (not mNodes[nodeId].leaf) then raise Exception.Create('invalid node id in TDynAABBTreeBase');
   // remove the node from the tree
   removeLeafNode(nodeId);
   releaseNode(nodeId);
 end;
 
 
-function TDynAABBTree.updateObject (nodeId: Integer; dispX, dispY: Float; forceReinsert: Boolean=false): Boolean;
+function TDynAABBTreeBase.updateObject (nodeId: Integer; forceReinsert: Boolean=false): Boolean; overload;
+var
+  newAABB: AABB2D;
+  dispX, dispY: TreeNumber;
+begin
+  if (nodeId < 0) or (nodeId >= mAllocCount) or (not mNodes[nodeId].leaf) then raise Exception.Create('invalid node id in TDynAABBTreeBase.updateObject');
+
+  if not getFleshAABB(newAABB, mNodes[nodeId].flesh, mNodes[nodeId].tag) then raise Exception.Create('invalid flesh dimensions in TDynAABBTreeBase.updateObject');
+  if not newAABB.valid then raise Exception.Create('invalid flesh aabb in TDynAABBTreeBase.updateObject');
+
+  dispX := newAABB.minX-mNodes[nodeId].fleshX;
+  dispY := newAABB.minY-mNodes[nodeId].fleshY;
+
+  if (dispX < -16) then dispX := -16 else if (dispX > 16) then dispX := 16;
+  if (dispY < -16) then dispY := -16 else if (dispY > 16) then dispY := 16;
+
+  result := updateObject(nodeId, dispX, dispY, forceReinsert);
+end;
+
+function TDynAABBTreeBase.updateObject (nodeId: Integer; dispX, dispY: TreeNumber; forceReinsert: Boolean=false): Boolean; overload;
 var
   newAABB: AABB2D;
+  fx, fy: Integer;
+  node: PTreeNode;
 begin
-  if (nodeId < 0) or (nodeId >= mNodeCount) or (not mNodes[nodeId].leaf) then raise Exception.Create('invalid node id in TDynAABBTree');
+  if (nodeId < 0) or (nodeId >= mAllocCount) or (not mNodes[nodeId].leaf) then raise Exception.Create('invalid node id in TDynAABBTreeBase.updateObject');
+
+  if not getFleshAABB(newAABB, mNodes[nodeId].flesh, mNodes[nodeId].tag) then raise Exception.Create('invalid flesh dimensions in TDynAABBTreeBase.updateObject');
+  if not newAABB.valid then raise Exception.Create('invalid flesh aabb in TDynAABBTreeBase.updateObject');
 
-  if not getFleshAABB(newAABB, mNodes[nodeId].flesh) then raise Exception.Create('invalid node id in TDynAABBTree');
+  fx := newAABB.minX;
+  fy := newAABB.minY;
 
   // if the new AABB is still inside the fat AABB of the node
-  if (not forceReinsert) and (mNodes[nodeId].aabb.contains(newAABB)) then begin result := false; exit; end;
+  if (not forceReinsert) and (mNodes[nodeId].aabb.contains(newAABB)) then
+  begin
+    node := @mNodes[nodeId];
+    node.fleshX := fx;
+    node.fleshY := fy;
+    result := false;
+    exit;
+  end;
 
   // if the new AABB is outside the fat AABB, we remove the corresponding node
   removeLeafNode(nodeId);
 
+  node := @mNodes[nodeId];
+
   // compute the fat AABB by inflating the AABB with a constant gap
-  mNodes[nodeId].aabb := newAABB;
-  if not forceReinsert and ((dispX <> 0) or (dispY <> 0)) then
+  node.aabb.copyFrom(newAABB);
+  node.fleshX := fx;
+  node.fleshY := fy;
+
+  if (not forceReinsert) and ((dispX <> 0) or (dispY <> 0)) then
   begin
-    mNodes[nodeId].aabb.minX := mNodes[nodeId].aabb.minX-mExtraGap;
-    mNodes[nodeId].aabb.minY := mNodes[nodeId].aabb.minY-mExtraGap;
-    mNodes[nodeId].aabb.maxX := mNodes[nodeId].aabb.maxX+mExtraGap;
-    mNodes[nodeId].aabb.maxY := mNodes[nodeId].aabb.maxY+mExtraGap;
+    node.aabb.minX -= mExtraGap;
+    node.aabb.minY += mExtraGap;
+    node.aabb.maxX += mExtraGap;
+    node.aabb.maxY += mExtraGap;
   end;
 
   // inflate the fat AABB in direction of the linear motion of the AABB
-  if (dispX < 0.0) then
+  if (dispX < 0) then
   begin
-    mNodes[nodeId].aabb.minX := mNodes[nodeId].aabb.minX+LinearMotionGapMultiplier*dispX;
+    node.aabb.minX += LinearMotionGapMultiplier*dispX {$IFDEF aabbtree_use_floats}{$ELSE}div 10{$ENDIF};
   end
   else
   begin
-    mNodes[nodeId].aabb.maxX := mNodes[nodeId].aabb.maxX+LinearMotionGapMultiplier*dispX;
+    node.aabb.maxX += LinearMotionGapMultiplier*dispX {$IFDEF aabbtree_use_floats}{$ELSE}div 10{$ENDIF};
   end;
-  if (dispY < 0.0) then
+
+  if (dispY < 0) then
   begin
-    mNodes[nodeId].aabb.minY := mNodes[nodeId].aabb.minY+LinearMotionGapMultiplier*dispY;
+    node.aabb.minY += LinearMotionGapMultiplier*dispY {$IFDEF aabbtree_use_floats}{$ELSE}div 10{$ENDIF};
   end
   else
   begin
-    mNodes[nodeId].aabb.maxY := mNodes[nodeId].aabb.maxY+LinearMotionGapMultiplier*dispY;
+    node.aabb.maxY += LinearMotionGapMultiplier*dispY {$IFDEF aabbtree_use_floats}{$ELSE}div 10{$ENDIF};
   end;
 
-  {$IFDEF aabbtree_many_asserts}assert(mNodes[nodeId].aabb.contains(newAABB));{$ENDIF}
+  {$IFDEF aabbtree_many_asserts}assert(node.aabb.contains(newAABB));{$ENDIF}
 
   // reinsert the node into the tree
   insertLeafNode(nodeId);
@@ -1320,100 +1528,143 @@ begin
 end;
 
 
+function TDynAABBTreeBase.checkerAABB (node: PTreeNode): Boolean;
+begin
+  result := chkAABB.overlaps(node.aabb);
+end;
+
+
 // report all shapes overlapping with the AABB given in parameter
-procedure TDynAABBTree.aabbQuery (ax, ay, aw, ah: Float; cb: TQueryOverlapCB);
+function TDynAABBTreeBase.aabbQuery (ax, ay, aw, ah: TreeNumber; cb: TQueryOverlapCB; tagmask: Integer=-1): TTreeFlesh;
 var
-  caabb: AABB2D;
-  function checker (node: PTreeNode): Boolean;
-  begin
-    result := caabb.overlaps(node.aabb);
-  end;
+  nid: Integer;
+  oldaabb: AABB2D;
 begin
+  result := Default(ITP);
   if not assigned(cb) then exit;
   if (aw < 1) or (ah < 1) then exit;
-  caabb := AABB2D.Create(ax, ay, ax+aw-1, ay+ah-1);
-  visit(checker, cb);
+  //chkAABB := AABB2D.Create(ax, ay, ax+aw, ay+ah);
+  oldaabb := chkAABB;
+  chkAABB.minX := ax;
+  chkAABB.minY := ay;
+  chkAABB.maxX := ax+aw;
+  chkAABB.maxY := ay+ah;
+  nid := visit(chkAABB, ModeAABB, checkerAABB, cb, nil, tagmask);
+  chkAABB := oldaabb;
+  if (nid >= 0) then result := mNodes[nid].flesh else result := Default(ITP);
+end;
+
+
+function TDynAABBTreeBase.checkerPoint (node: PTreeNode): Boolean;
+begin
+  result := node.aabb.contains(chkAABB.minX, chkAABB.minY);
 end;
 
 
 // report body that contains the given point, or nil
-function TDynAABBTree.pointQuery (ax, ay: Float; cb: TQueryOverlapCB): TTreeFlesh;
+function TDynAABBTreeBase.pointQuery (ax, ay: TreeNumber; cb: TQueryOverlapCB; tagmask: Integer=-1): TTreeFlesh;
 var
   nid: Integer;
-  function checker (node: PTreeNode): Boolean;
-  begin
-    result := node.aabb.contains(ax, ay);
-  end;
+  oldaabb: AABB2D;
 begin
-  nid := visit(checker, cb);
-  {$IFDEF aabbtree_many_asserts}assert((nid < 0) or ((nid >= 0) and (nid < mNodeCount) and (mNodes[nid].leaf)));{$ENDIF}
-  if (nid >= 0) then result := mNodes[nid].flesh else result := nil;
+  oldaabb := chkAABB;
+  chkAABB := AABB2D.Create(ax, ay, ax+1, ay+1);
+  nid := visit(chkAABB, ModePoint, checkerPoint, cb, nil, tagmask);
+  {$IFDEF aabbtree_many_asserts}assert((nid < 0) or ((nid >= 0) and (nid < mAllocCount) and (mNodes[nid].leaf)));{$ENDIF}
+  chkAABB := oldaabb;
+  if (nid >= 0) then result := mNodes[nid].flesh else result := Default(ITP);
 end;
 
 
-// segment querying method
-function TDynAABBTree.segmentQuery (var qr: TSegmentQueryResult; ax, ay, bx, by: Float; cb: TSegQueryCallback): Boolean;
-var
-  maxFraction: Float = 1.0e100; // infinity
-  curax, curay: Float;
-  curbx, curby: Float;
-  dirx, diry: Float;
-  invlen: Float;
+function TDynAABBTreeBase.checkerRay (node: PTreeNode): Boolean;
+begin
+  result := node.aabb.intersects(curax, curay, curbx, curby);
+end;
 
-  function checker (node: PTreeNode): Boolean;
+function TDynAABBTreeBase.visitorRay (flesh: TTreeFlesh; tag: Integer): Boolean;
+var
+  hitFraction: Single;
+begin
+  hitFraction := sqcb(flesh, curax, curay, curbx, curby);
+  // if the user returned a hitFraction of zero, it means that the raycasting should stop here
+  if (hitFraction = 0.0) then
   begin
-    result := node.aabb.intersects(curax, curay, curbx, curby);
+    qSRes.dist := 0;
+    qSRes.flesh := flesh;
+    result := true;
+    exit;
   end;
-
-  function visitor (flesh: TTreeFlesh): Boolean;
-  var
-    hitFraction: Float;
+  // if the user returned a positive fraction
+  if (hitFraction > 0.0) then
   begin
-    hitFraction := cb(flesh, curax, curay, curbx, curby);
-    // if the user returned a hitFraction of zero, it means that the raycasting should stop here
-    if (hitFraction = 0.0) then
-    begin
-      qr.dist := 0;
-      qr.flesh := flesh;
-      result := true;
-      exit;
-    end;
-    // if the user returned a positive fraction
-    if (hitFraction > 0.0) then
+    // we update the maxFraction value and the ray AABB using the new maximum fraction
+    if (hitFraction < maxFraction) then
     begin
-      // we update the maxFraction value and the ray AABB using the new maximum fraction
-      if (hitFraction < maxFraction) then
-      begin
-        maxFraction := hitFraction;
-        qr.dist := hitFraction;
-        qr.flesh := flesh;
-        // fix curb here
-        //curb := cura+dir*hitFraction;
-        curbx := curax+dirx*hitFraction;
-        curby := curay+diry*hitFraction;
-      end;
+      maxFraction := hitFraction;
+      qSRes.dist := hitFraction;
+      qSRes.flesh := flesh;
+      // fix curb here
+      //curb := cura+dir*hitFraction;
+      curbx := curax+dirx*hitFraction;
+      curby := curay+diry*hitFraction;
     end;
-    result := false; // continue
   end;
+  result := false; // continue
+end;
+
 
+// segment querying method
+function TDynAABBTreeBase.segmentQuery (out qr: TSegmentQueryResult; ax, ay, bx, by: TreeNumber; cb: TSegQueryCallback; tagmask: Integer=-1): Boolean;
+var
+  oldmaxFraction: Single;
+  oldcurax, oldcuray: Single;
+  oldcurbx, oldcurby: Single;
+  olddirx, olddiry: Single;
+  invlen: Single;
+  osres: PSegmentQueryResult;
+  osqcb: TSegQueryCallback;
 begin
-  qr.reset();
+  qr := TSegmentQueryResult.Create(false);
 
   if (ax >= bx) or (ay >= by) then begin result := false; exit; end;
 
+  oldmaxFraction := maxFraction;
+  oldcurax := curax;
+  oldcuray := curay;
+  oldcurbx := curbx;
+  oldcurby := curby;
+  olddirx := dirx;
+  olddiry := diry;
+
+  maxFraction := 1.0e100; // infinity
   curax := ax;
   curay := ay;
   curbx := bx;
   curby := by;
 
-  dirx := (curbx-curax);
-  diry := (curby-curay);
+  dirx := curbx-curax;
+  diry := curby-curay;
   // normalize
   invlen := 1.0/sqrt(dirx*dirx+diry*diry);
   dirx *= invlen;
   diry *= invlen;
 
-  visit(checker, visitor);
+  //chkAABB := AABB2D.Create(0, 0, 1, 1);
+  osres := qSRes;
+  qSRes := @qr;
+  osqcb := sqcb;
+  sqcb := cb;
+  visit(chkAABB, ModeNoChecks, checkerRay, nil, visitorRay, tagmask);
+  qSRes := osres;
+  sqcb := osqcb;
+
+  curax := oldcurax;
+  curay := oldcuray;
+  curbx := oldcurbx;
+  curby := oldcurby;
+  dirx := olddirx;
+  diry := olddiry;
+  maxFraction := oldmaxFraction;
 
   result := qr.valid;
 end;