hedgewars/uGearsHandlersRope.pas
changeset 7660 8398faa1e628
parent 7658 70a874a26414
child 7662 35d895dcd6f7
--- a/hedgewars/uGearsHandlersRope.pas	Mon Sep 03 20:04:42 2012 +0200
+++ b/hedgewars/uGearsHandlersRope.pas	Mon Sep 03 14:08:01 2012 -0400
@@ -1,462 +1,462 @@
-(*
- * Hedgewars, a free turn based strategy game
- * Copyright (c) 2004-2012 Andrey Korotaev <unC0Rr@gmail.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; version 2 of the License
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
- *)
-
-{$INCLUDE "options.inc"}
-unit uGearsHandlersRope;
-interface
-
-uses uTypes;
-
-procedure doStepRope(Gear: PGear);
-
-implementation
-uses uConsts, uFloat, uCollisions, uVariables, uGearsList, uSound, uGearsUtils,
-    uAmmos, uDebug, uUtils, uGearsHedgehog, uGearsRender;
-
-procedure doStepRopeAfterAttack(Gear: PGear);
-var 
-    HHGear: PGear;
-begin
-    HHGear := Gear^.Hedgehog^.Gear;
-    if ((HHGear^.State and gstHHDriven) = 0)
-    or (CheckGearDrowning(HHGear))
-    or (TestCollisionYwithGear(HHGear, 1) <> 0) then
-        begin
-        DeleteGear(Gear);
-        isCursorVisible := false;
-        ApplyAmmoChanges(HHGear^.Hedgehog^);
-        exit
-        end;
-
-    HedgehogChAngle(HHGear);
-
-    if TestCollisionXwithGear(HHGear, hwSign(HHGear^.dX)) then
-        SetLittle(HHGear^.dX);
-
-    if HHGear^.dY.isNegative and (TestCollisionYwithGear(HHGear, -1) <> 0) then
-        HHGear^.dY := _0;
-    HHGear^.X := HHGear^.X + HHGear^.dX;
-    HHGear^.Y := HHGear^.Y + HHGear^.dY;
-    HHGear^.dY := HHGear^.dY + cGravity;
-    
-    if (GameFlags and gfMoreWind) <> 0 then
-        HHGear^.dX := HHGear^.dX + cWindSpeed / HHGear^.Density;
-
-    if (Gear^.Message and gmAttack) <> 0 then
-        begin
-        Gear^.X := HHGear^.X;
-        Gear^.Y := HHGear^.Y;
-
-        ApplyAngleBounds(Gear^.Hedgehog^, amRope);
-
-        Gear^.dX := SignAs(AngleSin(HHGear^.Angle), HHGear^.dX);
-        Gear^.dY := -AngleCos(HHGear^.Angle);
-        Gear^.Friction := _4_5 * cRopePercent;
-        Gear^.Elasticity := _0;
-        Gear^.State := Gear^.State and (not gsttmpflag);
-        Gear^.doStep := @doStepRope;
-        end
-end;
-
-procedure RopeDeleteMe(Gear, HHGear: PGear);
-begin
-    with HHGear^ do
-        begin
-        Message := Message and (not gmAttack);
-        State := (State or gstMoving) and (not gstWinner);
-        end;
-    DeleteGear(Gear)
-end;
-
-procedure RopeWaitCollision(Gear, HHGear: PGear);
-begin
-    with HHGear^ do
-        begin
-        Message := Message and (not gmAttack);
-        State := State or gstMoving;
-        end;
-    RopePoints.Count := 0;
-    Gear^.Elasticity := _0;
-    Gear^.doStep := @doStepRopeAfterAttack
-end;
-
-procedure doStepRopeWork(Gear: PGear);
-var 
-    HHGear: PGear;
-    len, tx, ty, nx, ny, ropeDx, ropeDy, mdX, mdY: hwFloat;
-    lx, ly, cd: LongInt;
-    haveCollision,
-    haveDivided: boolean;
-
-begin
-    if GameTicks mod 4 <> 0 then exit;
-
-    HHGear := Gear^.Hedgehog^.Gear;
-
-    if ((HHGear^.State and gstHHDriven) = 0)
-       or (CheckGearDrowning(HHGear)) or (Gear^.PortalCounter <> 0) then
-        begin
-        PlaySound(sndRopeRelease);
-        RopeDeleteMe(Gear, HHGear);
-        exit
-        end;
-
-    HHGear^.dX.QWordValue:= HHGear^.dX.QWordValue shl 2;
-    HHGear^.dY.QWordValue:= HHGear^.dY.QWordValue shl 2;
-    if (Gear^.Message and gmLeft  <> 0) and (not TestCollisionXwithGear(HHGear, -1)) then
-        HHGear^.dX := HHGear^.dX - _0_0032;
-
-    if (Gear^.Message and gmRight <> 0) and (not TestCollisionXwithGear(HHGear,  1)) then
-        HHGear^.dX := HHGear^.dX + _0_0032;
-
-    // vector between hedgehog and rope attaching point
-    ropeDx := HHGear^.X - Gear^.X;
-    ropeDy := HHGear^.Y - Gear^.Y;
-
-    if TestCollisionYwithGear(HHGear, 1) = 0 then
-        begin
-
-        // depending on the rope vector we know which X-side to check for collision
-        // in order to find out if the hog can still be moved by gravity
-        if ropeDx.isNegative = RopeDy.IsNegative then
-            cd:= -1
-        else
-            cd:= 1;
-
-        // apply gravity if there is no obstacle
-        if not TestCollisionXwithGear(HHGear, cd) then
-            HHGear^.dY := HHGear^.dY + cGravity * 16;
-
-        if (GameFlags and gfMoreWind) <> 0 then
-            // apply wind if there's no obstacle
-            if not TestCollisionXwithGear(HHGear, hwSign(cWindSpeed)) then
-                HHGear^.dX := HHGear^.dX + cWindSpeed * 16 / HHGear^.Density;
-        end;
-
-    mdX := ropeDx + HHGear^.dX;
-    mdY := ropeDy + HHGear^.dY;
-    len := _1 / Distance(mdX, mdY);
-    // rope vector plus hedgehog direction vector normalized
-    mdX := mdX * len;
-    mdY := mdY * len;
-
-    // for visual purposes only
-    Gear^.dX := mdX;
-    Gear^.dY := mdY;
-
-    /////
-    tx := HHGear^.X;
-    ty := HHGear^.Y;
-
-    if ((Gear^.Message and gmDown) <> 0) and (Gear^.Elasticity < Gear^.Friction) then
-        if not (TestCollisionXwithGear(HHGear, hwSign(ropeDx))
-        or (TestCollisionYwithGear(HHGear, hwSign(ropeDy)) <> 0)) then
-            Gear^.Elasticity := Gear^.Elasticity + _1_2;
-
-    if ((Gear^.Message and gmUp) <> 0) and (Gear^.Elasticity > _30) then
-        if not (TestCollisionXwithGear(HHGear, -hwSign(ropeDx))
-        or (TestCollisionYwithGear(HHGear, -hwSign(ropeDy)) <> 0)) then
-            Gear^.Elasticity := Gear^.Elasticity - _1_2;
-
-    HHGear^.X := Gear^.X + mdX * Gear^.Elasticity;
-    HHGear^.Y := Gear^.Y + mdY * Gear^.Elasticity;
-
-    HHGear^.dX := HHGear^.X - tx;
-    HHGear^.dY := HHGear^.Y - ty;
-    ////
-
-
-    haveDivided := false;
-    // check whether rope needs dividing
-
-    len := Gear^.Elasticity - _5;
-    nx := Gear^.X + mdX * len;
-    ny := Gear^.Y + mdY * len;
-    tx := mdX * _1_2; // should be the same as increase step
-    ty := mdY * _1_2;
-
-    while len > _3 do
-        begin
-        lx := hwRound(nx);
-        ly := hwRound(ny);
-        if ((ly and LAND_HEIGHT_MASK) = 0) and ((lx and LAND_WIDTH_MASK) = 0) and ((Land[ly, lx] and $FF00) <> 0) then
-            begin
-            ny := _1 / Distance(ropeDx, ropeDy);
-            // old rope pos
-            nx := ropeDx * ny;
-            ny := ropeDy * ny;
-
-            with RopePoints.ar[RopePoints.Count] do
-                begin
-                X := Gear^.X;
-                Y := Gear^.Y;
-                if RopePoints.Count = 0 then
-                    RopePoints.HookAngle := DxDy2Angle(Gear^.dY, Gear^.dX);
-                b := (nx * HHGear^.dY) > (ny * HHGear^.dX);
-                dLen := len
-                end;
-                
-            with RopePoints.rounded[RopePoints.Count] do
-                begin
-                X := hwRound(Gear^.X);
-                Y := hwRound(Gear^.Y);
-                end;
-
-            Gear^.X := Gear^.X + nx * len;
-            Gear^.Y := Gear^.Y + ny * len;
-            inc(RopePoints.Count);
-            TryDo(RopePoints.Count <= MAXROPEPOINTS, 'Rope points overflow', true);
-            Gear^.Elasticity := Gear^.Elasticity - len;
-            Gear^.Friction := Gear^.Friction - len;
-            haveDivided := true;
-            break
-            end;
-        nx := nx - tx;
-        ny := ny - ty;
-
-        // len := len - _1_2 // should be the same as increase step
-        len.QWordValue := len.QWordValue - _1_2.QWordValue;
-        end;
-
-    if not haveDivided then
-        if RopePoints.Count > 0 then // check whether the last dividing point could be removed
-            begin
-            tx := RopePoints.ar[Pred(RopePoints.Count)].X;
-            ty := RopePoints.ar[Pred(RopePoints.Count)].Y;
-            mdX := tx - Gear^.X;
-            mdY := ty - Gear^.Y;
-            if RopePoints.ar[Pred(RopePoints.Count)].b xor (mdX * (ty - HHGear^.Y) > (tx - HHGear^.X) * mdY) then
-                begin
-                dec(RopePoints.Count);
-                Gear^.X := RopePoints.ar[RopePoints.Count].X;
-                Gear^.Y := RopePoints.ar[RopePoints.Count].Y;
-                Gear^.Elasticity := Gear^.Elasticity + RopePoints.ar[RopePoints.Count].dLen;
-                Gear^.Friction := Gear^.Friction + RopePoints.ar[RopePoints.Count].dLen;
-
-                // restore hog position
-                len := _1 / Distance(mdX, mdY);
-                mdX := mdX * len;
-                mdY := mdY * len;
-
-                HHGear^.X := Gear^.X - mdX * Gear^.Elasticity;
-                HHGear^.Y := Gear^.Y - mdY * Gear^.Elasticity;
-                end
-            end;
-
-    haveCollision := false;
-    if TestCollisionXwithGear(HHGear, hwSign(HHGear^.dX)) then
-        begin
-        HHGear^.dX := -_0_6 * HHGear^.dX;
-        haveCollision := true
-        end;
-    if TestCollisionYwithGear(HHGear, hwSign(HHGear^.dY)) <> 0 then
-        begin
-        HHGear^.dY := -_0_6 * HHGear^.dY;
-        haveCollision := true
-        end;
-
-    if haveCollision and (Gear^.Message and (gmLeft or gmRight) <> 0) and (Gear^.Message and (gmUp or gmDown) <> 0) then
-        begin
-        HHGear^.dX := SignAs(hwAbs(HHGear^.dX) + _0_8, HHGear^.dX);
-        HHGear^.dY := SignAs(hwAbs(HHGear^.dY) + _0_8, HHGear^.dY)
-        end;
-
-    len := hwSqr(HHGear^.dX) + hwSqr(HHGear^.dY);
-    if len > _10 then
-        begin
-        len := _3_2 / hwSqrt(len);
-        HHGear^.dX := HHGear^.dX * len;
-        HHGear^.dY := HHGear^.dY * len;
-        end;
-
-    haveCollision:= ((hwRound(Gear^.Y) and LAND_HEIGHT_MASK) = 0) and ((hwRound(Gear^.X) and LAND_WIDTH_MASK) = 0) and ((Land[hwRound(Gear^.Y), hwRound(Gear^.X)]) <> 0);
-
-    if not haveCollision then
-        begin
-        // backup gear location
-        tx:= Gear^.X;
-        ty:= Gear^.Y;
-
-        if RopePoints.Count > 0 then
-            begin
-            // set gear location to the remote end of the rope, the attachment point
-            Gear^.X:= RopePoints.ar[0].X;
-            Gear^.Y:= RopePoints.ar[0].Y;
-            end;
-
-        CheckCollision(Gear);
-        // if we haven't found any collision yet then check the other side too
-        if (Gear^.State and gstCollision) = 0 then
-            begin
-            Gear^.dX.isNegative:= not Gear^.dX.isNegative;
-            Gear^.dY.isNegative:= not Gear^.dY.isNegative;
-            CheckCollision(Gear);
-            Gear^.dX.isNegative:= not Gear^.dX.isNegative;
-            Gear^.dY.isNegative:= not Gear^.dY.isNegative;
-            end;
-
-        haveCollision:= (Gear^.State and gstCollision) <> 0;
-
-        // restore gear location
-        Gear^.X:= tx;
-        Gear^.Y:= ty;
-        end;
-
-    // if the attack key is pressed, lose rope contact as well
-    if (Gear^.Message and gmAttack) <> 0 then
-        haveCollision:= false;
-
-    HHGear^.dX.QWordValue:= HHGear^.dX.QWordValue shr 2;
-    HHGear^.dY.QWordValue:= HHGear^.dY.QWordValue shr 2;
-    if not haveCollision then
-        begin
-        if (Gear^.State and gsttmpFlag) <> 0 then
-            begin
-            PlaySound(sndRopeRelease);
-            if Gear^.Hedgehog^.CurAmmoType <> amParachute then
-                RopeWaitCollision(Gear, HHGear)
-            else
-                RopeDeleteMe(Gear, HHGear)
-            end
-        end
-    else
-        if (Gear^.State and gsttmpFlag) = 0 then
-            Gear^.State := Gear^.State or gsttmpFlag;
-end;
-
-procedure RopeRemoveFromAmmo(Gear, HHGear: PGear);
-begin
-    if (Gear^.State and gstAttacked) = 0 then
-        begin
-        OnUsedAmmo(HHGear^.Hedgehog^);
-        Gear^.State := Gear^.State or gstAttacked
-        end;
-    ApplyAmmoChanges(HHGear^.Hedgehog^)
-end;
-
-procedure doStepRopeAttach(Gear: PGear);
-var 
-    HHGear: PGear;
-    tx, ty, tt: hwFloat;
-begin
-    Gear^.X := Gear^.X - Gear^.dX;
-    Gear^.Y := Gear^.Y - Gear^.dY;
-    Gear^.Elasticity := Gear^.Elasticity + _1;
-
-    HHGear := Gear^.Hedgehog^.Gear;
-    DeleteCI(HHGear);
-
-    if (HHGear^.State and gstMoving) <> 0 then
-        begin
-        if TestCollisionXwithGear(HHGear, hwSign(HHGear^.dX)) then
-            SetLittle(HHGear^.dX);
-        if HHGear^.dY.isNegative and (TestCollisionYwithGear(HHGear, -1) <> 0) then
-            HHGear^.dY := _0;
-
-        HHGear^.X := HHGear^.X + HHGear^.dX;
-        Gear^.X := Gear^.X + HHGear^.dX;
-
-        if TestCollisionYwithGear(HHGear, 1) <> 0 then
-            begin
-            CheckHHDamage(HHGear);
-            HHGear^.dY := _0
-            //HHGear^.State:= HHGear^.State and (not (gstHHJumping or gstHHHJump));
-            end
-        else
-            begin
-            HHGear^.Y := HHGear^.Y + HHGear^.dY;
-            Gear^.Y := Gear^.Y + HHGear^.dY;
-            HHGear^.dY := HHGear^.dY + cGravity;
-            if (GameFlags and gfMoreWind) <> 0 then
-                HHGear^.dX := HHGear^.dX + cWindSpeed / HHGear^.Density
-            end;
-
-        tt := Gear^.Elasticity;
-        tx := _0;
-        ty := _0;
-        while tt > _20 do
-            begin
-            if ((hwRound(Gear^.Y+ty) and LAND_HEIGHT_MASK) = 0) and ((hwRound(Gear^.X+tx) and LAND_WIDTH_MASK) = 0) and ((Land[hwRound(Gear^.Y+ty), hwRound(Gear^.X+tx)] and $FF00) <> 0) then
-                begin
-                Gear^.X := Gear^.X + tx;
-                Gear^.Y := Gear^.Y + ty;
-                Gear^.Elasticity := tt;
-                Gear^.doStep := @doStepRopeWork;
-                PlaySound(sndRopeAttach);
-                with HHGear^ do
-                    begin
-                    State := State and (not (gstAttacking or gstHHJumping or gstHHHJump));
-                    Message := Message and (not gmAttack)
-                    end;
-
-                RopeRemoveFromAmmo(Gear, HHGear);
-
-                tt := _0;
-                exit
-                end;
-            tx := tx + Gear^.dX + Gear^.dX;
-            ty := ty + Gear^.dY + Gear^.dY;
-            tt := tt - _2;
-            end;
-        end;
-
-    CheckCollision(Gear);
-
-    if (Gear^.State and gstCollision) <> 0 then
-        if Gear^.Elasticity < _10 then
-            Gear^.Elasticity := _10000
-    else
-        begin
-        Gear^.doStep := @doStepRopeWork;
-        PlaySound(sndRopeAttach);
-        with HHGear^ do
-            begin
-            State := State and (not (gstAttacking or gstHHJumping or gstHHHJump));
-            Message := Message and (not gmAttack)
-            end;
-
-        RopeRemoveFromAmmo(Gear, HHGear);
-
-        exit
-        end;
-
-    if (Gear^.Elasticity > Gear^.Friction)
-        or ((Gear^.Message and gmAttack) = 0)
-        or ((HHGear^.State and gstHHDriven) = 0)
-        or (HHGear^.Damage > 0) then
-            begin
-            with Gear^.Hedgehog^.Gear^ do
-                begin
-                State := State and (not gstAttacking);
-                Message := Message and (not gmAttack)
-                end;
-        DeleteGear(Gear);
-        exit;
-        end;
-    if CheckGearDrowning(HHGear) then DeleteGear(Gear)
-end;
-
-procedure doStepRope(Gear: PGear);
-begin
-    Gear^.dX := - Gear^.dX;
-    Gear^.dY := - Gear^.dY;
-    Gear^.doStep := @doStepRopeAttach;
-    PlaySound(sndRopeShot)
-end;
-
-end.
+(*
+ * Hedgewars, a free turn based strategy game
+ * Copyright (c) 2004-2012 Andrey Korotaev <unC0Rr@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ *)
+
+{$INCLUDE "options.inc"}
+unit uGearsHandlersRope;
+interface
+
+uses uTypes;
+
+procedure doStepRope(Gear: PGear);
+
+implementation
+uses uConsts, uFloat, uCollisions, uVariables, uGearsList, uSound, uGearsUtils,
+    uAmmos, uDebug, uUtils, uGearsHedgehog, uGearsRender;
+
+procedure doStepRopeAfterAttack(Gear: PGear);
+var 
+    HHGear: PGear;
+begin
+    HHGear := Gear^.Hedgehog^.Gear;
+    if ((HHGear^.State and gstHHDriven) = 0)
+    or (CheckGearDrowning(HHGear))
+    or (TestCollisionYwithGear(HHGear, 1) <> 0) then
+        begin
+        DeleteGear(Gear);
+        isCursorVisible := false;
+        ApplyAmmoChanges(HHGear^.Hedgehog^);
+        exit
+        end;
+
+    HedgehogChAngle(HHGear);
+
+    if TestCollisionXwithGear(HHGear, hwSign(HHGear^.dX)) then
+        SetLittle(HHGear^.dX);
+
+    if HHGear^.dY.isNegative and (TestCollisionYwithGear(HHGear, -1) <> 0) then
+        HHGear^.dY := _0;
+    HHGear^.X := HHGear^.X + HHGear^.dX;
+    HHGear^.Y := HHGear^.Y + HHGear^.dY;
+    HHGear^.dY := HHGear^.dY + cGravity;
+    
+    if (GameFlags and gfMoreWind) <> 0 then
+        HHGear^.dX := HHGear^.dX + cWindSpeed / HHGear^.Density;
+
+    if (Gear^.Message and gmAttack) <> 0 then
+        begin
+        Gear^.X := HHGear^.X;
+        Gear^.Y := HHGear^.Y;
+
+        ApplyAngleBounds(Gear^.Hedgehog^, amRope);
+
+        Gear^.dX := SignAs(AngleSin(HHGear^.Angle), HHGear^.dX);
+        Gear^.dY := -AngleCos(HHGear^.Angle);
+        Gear^.Friction := _4_5 * cRopePercent;
+        Gear^.Elasticity := _0;
+        Gear^.State := Gear^.State and (not gsttmpflag);
+        Gear^.doStep := @doStepRope;
+        end
+end;
+
+procedure RopeDeleteMe(Gear, HHGear: PGear);
+begin
+    with HHGear^ do
+        begin
+        Message := Message and (not gmAttack);
+        State := (State or gstMoving) and (not gstWinner);
+        end;
+    DeleteGear(Gear)
+end;
+
+procedure RopeWaitCollision(Gear, HHGear: PGear);
+begin
+    with HHGear^ do
+        begin
+        Message := Message and (not gmAttack);
+        State := State or gstMoving;
+        end;
+    RopePoints.Count := 0;
+    Gear^.Elasticity := _0;
+    Gear^.doStep := @doStepRopeAfterAttack
+end;
+
+procedure doStepRopeWork(Gear: PGear);
+var 
+    HHGear: PGear;
+    len, tx, ty, nx, ny, ropeDx, ropeDy, mdX, mdY: hwFloat;
+    lx, ly, cd: LongInt;
+    haveCollision,
+    haveDivided: boolean;
+
+begin
+    if GameTicks mod 4 <> 0 then exit;
+
+    HHGear := Gear^.Hedgehog^.Gear;
+
+    if ((HHGear^.State and gstHHDriven) = 0)
+       or (CheckGearDrowning(HHGear)) or (Gear^.PortalCounter <> 0) then
+        begin
+        PlaySound(sndRopeRelease);
+        RopeDeleteMe(Gear, HHGear);
+        exit
+        end;
+
+    HHGear^.dX.QWordValue:= HHGear^.dX.QWordValue shl 2;
+    HHGear^.dY.QWordValue:= HHGear^.dY.QWordValue shl 2;
+    if (Gear^.Message and gmLeft  <> 0) and (not TestCollisionXwithGear(HHGear, -1)) then
+        HHGear^.dX := HHGear^.dX - _0_0032;
+
+    if (Gear^.Message and gmRight <> 0) and (not TestCollisionXwithGear(HHGear,  1)) then
+        HHGear^.dX := HHGear^.dX + _0_0032;
+
+    // vector between hedgehog and rope attaching point
+    ropeDx := HHGear^.X - Gear^.X;
+    ropeDy := HHGear^.Y - Gear^.Y;
+
+    if TestCollisionYwithGear(HHGear, 1) = 0 then
+        begin
+
+        // depending on the rope vector we know which X-side to check for collision
+        // in order to find out if the hog can still be moved by gravity
+        if ropeDx.isNegative = RopeDy.IsNegative then
+            cd:= -1
+        else
+            cd:= 1;
+
+        // apply gravity if there is no obstacle
+        if not TestCollisionXwithGear(HHGear, cd) then
+            HHGear^.dY := HHGear^.dY + cGravity * 16;
+
+        if (GameFlags and gfMoreWind) <> 0 then
+            // apply wind if there's no obstacle
+            if not TestCollisionXwithGear(HHGear, hwSign(cWindSpeed)) then
+                HHGear^.dX := HHGear^.dX + cWindSpeed * 16 / HHGear^.Density;
+        end;
+
+    mdX := ropeDx + HHGear^.dX;
+    mdY := ropeDy + HHGear^.dY;
+    len := _1 / Distance(mdX, mdY);
+    // rope vector plus hedgehog direction vector normalized
+    mdX := mdX * len;
+    mdY := mdY * len;
+
+    // for visual purposes only
+    Gear^.dX := mdX;
+    Gear^.dY := mdY;
+
+    /////
+    tx := HHGear^.X;
+    ty := HHGear^.Y;
+
+    if ((Gear^.Message and gmDown) <> 0) and (Gear^.Elasticity < Gear^.Friction) then
+        if not (TestCollisionXwithGear(HHGear, hwSign(ropeDx))
+        or (TestCollisionYwithGear(HHGear, hwSign(ropeDy)) <> 0)) then
+            Gear^.Elasticity := Gear^.Elasticity + _1_2;
+
+    if ((Gear^.Message and gmUp) <> 0) and (Gear^.Elasticity > _30) then
+        if not (TestCollisionXwithGear(HHGear, -hwSign(ropeDx))
+        or (TestCollisionYwithGear(HHGear, -hwSign(ropeDy)) <> 0)) then
+            Gear^.Elasticity := Gear^.Elasticity - _1_2;
+
+    HHGear^.X := Gear^.X + mdX * Gear^.Elasticity;
+    HHGear^.Y := Gear^.Y + mdY * Gear^.Elasticity;
+
+    HHGear^.dX := HHGear^.X - tx;
+    HHGear^.dY := HHGear^.Y - ty;
+    ////
+
+
+    haveDivided := false;
+    // check whether rope needs dividing
+
+    len := Gear^.Elasticity - _5;
+    nx := Gear^.X + mdX * len;
+    ny := Gear^.Y + mdY * len;
+    tx := mdX * _1_2; // should be the same as increase step
+    ty := mdY * _1_2;
+
+    while len > _3 do
+        begin
+        lx := hwRound(nx);
+        ly := hwRound(ny);
+        if ((ly and LAND_HEIGHT_MASK) = 0) and ((lx and LAND_WIDTH_MASK) = 0) and ((Land[ly, lx] and $FF00) <> 0) then
+            begin
+            ny := _1 / Distance(ropeDx, ropeDy);
+            // old rope pos
+            nx := ropeDx * ny;
+            ny := ropeDy * ny;
+
+            with RopePoints.ar[RopePoints.Count] do
+                begin
+                X := Gear^.X;
+                Y := Gear^.Y;
+                if RopePoints.Count = 0 then
+                    RopePoints.HookAngle := DxDy2Angle(Gear^.dY, Gear^.dX);
+                b := (nx * HHGear^.dY) > (ny * HHGear^.dX);
+                dLen := len
+                end;
+                
+            with RopePoints.rounded[RopePoints.Count] do
+                begin
+                X := hwRound(Gear^.X);
+                Y := hwRound(Gear^.Y);
+                end;
+
+            Gear^.X := Gear^.X + nx * len;
+            Gear^.Y := Gear^.Y + ny * len;
+            inc(RopePoints.Count);
+            TryDo(RopePoints.Count <= MAXROPEPOINTS, 'Rope points overflow', true);
+            Gear^.Elasticity := Gear^.Elasticity - len;
+            Gear^.Friction := Gear^.Friction - len;
+            haveDivided := true;
+            break
+            end;
+        nx := nx - tx;
+        ny := ny - ty;
+
+        // len := len - _1_2 // should be the same as increase step
+        len.QWordValue := len.QWordValue - _1_2.QWordValue;
+        end;
+
+    if not haveDivided then
+        if RopePoints.Count > 0 then // check whether the last dividing point could be removed
+            begin
+            tx := RopePoints.ar[Pred(RopePoints.Count)].X;
+            ty := RopePoints.ar[Pred(RopePoints.Count)].Y;
+            mdX := tx - Gear^.X;
+            mdY := ty - Gear^.Y;
+            if RopePoints.ar[Pred(RopePoints.Count)].b xor (mdX * (ty - HHGear^.Y) > (tx - HHGear^.X) * mdY) then
+                begin
+                dec(RopePoints.Count);
+                Gear^.X := RopePoints.ar[RopePoints.Count].X;
+                Gear^.Y := RopePoints.ar[RopePoints.Count].Y;
+                Gear^.Elasticity := Gear^.Elasticity + RopePoints.ar[RopePoints.Count].dLen;
+                Gear^.Friction := Gear^.Friction + RopePoints.ar[RopePoints.Count].dLen;
+
+                // restore hog position
+                len := _1 / Distance(mdX, mdY);
+                mdX := mdX * len;
+                mdY := mdY * len;
+
+                HHGear^.X := Gear^.X - mdX * Gear^.Elasticity;
+                HHGear^.Y := Gear^.Y - mdY * Gear^.Elasticity;
+                end
+            end;
+
+    haveCollision := false;
+    if TestCollisionXwithGear(HHGear, hwSign(HHGear^.dX)) then
+        begin
+        HHGear^.dX := -_0_6 * HHGear^.dX;
+        haveCollision := true
+        end;
+    if TestCollisionYwithGear(HHGear, hwSign(HHGear^.dY)) <> 0 then
+        begin
+        HHGear^.dY := -_0_6 * HHGear^.dY;
+        haveCollision := true
+        end;
+
+    if haveCollision and (Gear^.Message and (gmLeft or gmRight) <> 0) and (Gear^.Message and (gmUp or gmDown) <> 0) then
+        begin
+        HHGear^.dX := SignAs(hwAbs(HHGear^.dX) + _0_8, HHGear^.dX);
+        HHGear^.dY := SignAs(hwAbs(HHGear^.dY) + _0_8, HHGear^.dY)
+        end;
+
+    len := hwSqr(HHGear^.dX) + hwSqr(HHGear^.dY);
+    if len > _10 then
+        begin
+        len := _3_2 / hwSqrt(len);
+        HHGear^.dX := HHGear^.dX * len;
+        HHGear^.dY := HHGear^.dY * len;
+        end;
+
+    haveCollision:= ((hwRound(Gear^.Y) and LAND_HEIGHT_MASK) = 0) and ((hwRound(Gear^.X) and LAND_WIDTH_MASK) = 0) and ((Land[hwRound(Gear^.Y), hwRound(Gear^.X)]) <> 0);
+
+    if not haveCollision then
+        begin
+        // backup gear location
+        tx:= Gear^.X;
+        ty:= Gear^.Y;
+
+        if RopePoints.Count > 0 then
+            begin
+            // set gear location to the remote end of the rope, the attachment point
+            Gear^.X:= RopePoints.ar[0].X;
+            Gear^.Y:= RopePoints.ar[0].Y;
+            end;
+
+        CheckCollision(Gear);
+        // if we haven't found any collision yet then check the other side too
+        if (Gear^.State and gstCollision) = 0 then
+            begin
+            Gear^.dX.isNegative:= not Gear^.dX.isNegative;
+            Gear^.dY.isNegative:= not Gear^.dY.isNegative;
+            CheckCollision(Gear);
+            Gear^.dX.isNegative:= not Gear^.dX.isNegative;
+            Gear^.dY.isNegative:= not Gear^.dY.isNegative;
+            end;
+
+        haveCollision:= (Gear^.State and gstCollision) <> 0;
+
+        // restore gear location
+        Gear^.X:= tx;
+        Gear^.Y:= ty;
+        end;
+
+    // if the attack key is pressed, lose rope contact as well
+    if (Gear^.Message and gmAttack) <> 0 then
+        haveCollision:= false;
+
+    HHGear^.dX.QWordValue:= HHGear^.dX.QWordValue shr 2;
+    HHGear^.dY.QWordValue:= HHGear^.dY.QWordValue shr 2;
+    if not haveCollision then
+        begin
+        if (Gear^.State and gsttmpFlag) <> 0 then
+            begin
+            PlaySound(sndRopeRelease);
+            if Gear^.Hedgehog^.CurAmmoType <> amParachute then
+                RopeWaitCollision(Gear, HHGear)
+            else
+                RopeDeleteMe(Gear, HHGear)
+            end
+        end
+    else
+        if (Gear^.State and gsttmpFlag) = 0 then
+            Gear^.State := Gear^.State or gsttmpFlag;
+end;
+
+procedure RopeRemoveFromAmmo(Gear, HHGear: PGear);
+begin
+    if (Gear^.State and gstAttacked) = 0 then
+        begin
+        OnUsedAmmo(HHGear^.Hedgehog^);
+        Gear^.State := Gear^.State or gstAttacked
+        end;
+    ApplyAmmoChanges(HHGear^.Hedgehog^)
+end;
+
+procedure doStepRopeAttach(Gear: PGear);
+var 
+    HHGear: PGear;
+    tx, ty, tt: hwFloat;
+begin
+    Gear^.X := Gear^.X - Gear^.dX;
+    Gear^.Y := Gear^.Y - Gear^.dY;
+    Gear^.Elasticity := Gear^.Elasticity + _1;
+
+    HHGear := Gear^.Hedgehog^.Gear;
+    DeleteCI(HHGear);
+
+    if (HHGear^.State and gstMoving) <> 0 then
+        begin
+        if TestCollisionXwithGear(HHGear, hwSign(HHGear^.dX)) then
+            SetLittle(HHGear^.dX);
+        if HHGear^.dY.isNegative and (TestCollisionYwithGear(HHGear, -1) <> 0) then
+            HHGear^.dY := _0;
+
+        HHGear^.X := HHGear^.X + HHGear^.dX;
+        Gear^.X := Gear^.X + HHGear^.dX;
+
+        if TestCollisionYwithGear(HHGear, 1) <> 0 then
+            begin
+            CheckHHDamage(HHGear);
+            HHGear^.dY := _0
+            //HHGear^.State:= HHGear^.State and (not (gstHHJumping or gstHHHJump));
+            end
+        else
+            begin
+            HHGear^.Y := HHGear^.Y + HHGear^.dY;
+            Gear^.Y := Gear^.Y + HHGear^.dY;
+            HHGear^.dY := HHGear^.dY + cGravity;
+            if (GameFlags and gfMoreWind) <> 0 then
+                HHGear^.dX := HHGear^.dX + cWindSpeed / HHGear^.Density
+            end;
+
+        tt := Gear^.Elasticity;
+        tx := _0;
+        ty := _0;
+        while tt > _20 do
+            begin
+            if ((hwRound(Gear^.Y+ty) and LAND_HEIGHT_MASK) = 0) and ((hwRound(Gear^.X+tx) and LAND_WIDTH_MASK) = 0) and ((Land[hwRound(Gear^.Y+ty), hwRound(Gear^.X+tx)] and $FF00) <> 0) then
+                begin
+                Gear^.X := Gear^.X + tx;
+                Gear^.Y := Gear^.Y + ty;
+                Gear^.Elasticity := tt;
+                Gear^.doStep := @doStepRopeWork;
+                PlaySound(sndRopeAttach);
+                with HHGear^ do
+                    begin
+                    State := State and (not (gstAttacking or gstHHJumping or gstHHHJump));
+                    Message := Message and (not gmAttack)
+                    end;
+
+                RopeRemoveFromAmmo(Gear, HHGear);
+
+                tt := _0;
+                exit
+                end;
+            tx := tx + Gear^.dX + Gear^.dX;
+            ty := ty + Gear^.dY + Gear^.dY;
+            tt := tt - _2;
+            end;
+        end;
+
+    CheckCollision(Gear);
+
+    if (Gear^.State and gstCollision) <> 0 then
+        if Gear^.Elasticity < _10 then
+            Gear^.Elasticity := _10000
+    else
+        begin
+        Gear^.doStep := @doStepRopeWork;
+        PlaySound(sndRopeAttach);
+        with HHGear^ do
+            begin
+            State := State and (not (gstAttacking or gstHHJumping or gstHHHJump));
+            Message := Message and (not gmAttack)
+            end;
+
+        RopeRemoveFromAmmo(Gear, HHGear);
+
+        exit
+        end;
+
+    if (Gear^.Elasticity > Gear^.Friction)
+        or ((Gear^.Message and gmAttack) = 0)
+        or ((HHGear^.State and gstHHDriven) = 0)
+        or (HHGear^.Damage > 0) then
+            begin
+            with Gear^.Hedgehog^.Gear^ do
+                begin
+                State := State and (not gstAttacking);
+                Message := Message and (not gmAttack)
+                end;
+        DeleteGear(Gear);
+        exit;
+        end;
+    if CheckGearDrowning(HHGear) then DeleteGear(Gear)
+end;
+
+procedure doStepRope(Gear: PGear);
+begin
+    Gear^.dX := - Gear^.dX;
+    Gear^.dY := - Gear^.dY;
+    Gear^.doStep := @doStepRopeAttach;
+    PlaySound(sndRopeShot)
+end;
+
+end.