X-Git-Url: http://deadsoftware.ru/gitweb?a=blobdiff_plain;f=src%2Fgame%2Fg_gfx.pas;h=3a9c79cf7b7102bce7e6e22e00dcd8e6008a491d;hb=aab9c00a40aebab672c35d10258404b6eea517e7;hp=4ea5772731821c5bf67d0e1a8ddc76c3184030bb;hpb=44103c4d02f0720ffd6fa801e2d2b09f596d6b6e;p=d2df-sdl.git

diff --git a/src/game/g_gfx.pas b/src/game/g_gfx.pas
index 4ea5772..3a9c79c 100644
--- a/src/game/g_gfx.pas
+++ b/src/game/g_gfx.pas
@@ -1,9 +1,8 @@
-(* Copyright (C)  DooM 2D:Forever Developers
+(* Copyright (C)  Doom 2D: Forever Developers
  *
  * 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, either version 3 of the License, or
- * (at your option) any later version.
+ * the Free Software Foundation, version 3 of the License ONLY.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -14,7 +13,8 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  *)
 {$INCLUDE ../shared/a_modes.inc}
-{$DEFINE D2F_NEW_SPARK_THINKER}
+{.$DEFINE D2F_DEBUG_FALL_MPLAT}
+{/$DEFINE D2F_DEBUG_PART_AWAKE}
 unit g_gfx;
 
 interface
@@ -25,6 +25,8 @@ uses
 const
   BLOOD_NORMAL = 0;
   BLOOD_SPARKS = 1;
+  BLOOD_CSPARKS = 2;
+  BLOOD_COMBINE = 3;
 
   ONCEANIM_NONE  = 0;
   ONCEANIM_SMOKE = 1;
@@ -62,18 +64,79 @@ procedure g_GFX_OnceAnim (X, Y: Integer; Anim: TAnimation; AnimType: Byte = 0);
 procedure g_Mark (x, y, Width, Height: Integer; t: Byte; st: Boolean=true);
 
 procedure g_GFX_Update ();
-procedure g_GFX_Draw ();
-
 
 var
   gpart_dbg_enabled: Boolean = true;
   gpart_dbg_phys_enabled: Boolean = true;
 
 
+//WARNING: only for Holmes!
+function awmIsSetHolmes (x, y: Integer): Boolean; inline;
+
+  type (* private state *)
+    TPartType = (Blood, Spark, Bubbles, Water);
+    TPartState = (Free, Normal, Stuck, Sleeping);
+    TFloorType = (Wall, LiquidIn, LiquidOut);
+      // Wall: floorY is just before floor
+      // LiquidIn: floorY is liquid *start* (i.e. just in a liquid)
+      // LiquidOut: floorY is liquid *end* (i.e. just out of a liquid)
+    TEnvType = (EAir, ELiquid, EWall); // where particle is now
+
+    // note: this MUST be record, so we can keep it in
+    // dynamic array and has sequential memory access pattern
+    PParticle = ^TParticle;
+    TParticle = record
+      x, y: Integer;
+      oldX, oldY: Integer;
+      velX, velY: Single;
+      accelX, accelY: Single;
+      state: TPartState;
+      particleType: TPartType;
+      red, green, blue: Byte;
+      alpha: Byte;
+      time, liveTime, waitTime: Word;
+      stickDX: Integer; // STATE_STICK: -1,1: stuck to a wall; 0: stuck to ceiling
+      justSticked: Boolean; // not used
+      floorY: Integer; // actually, floor-1; `Unknown`: unknown
+      floorType: TFloorType;
+      env: TEnvType; // where particle is now
+      ceilingY: Integer; // actually, ceiling+1; `Unknown`: unknown
+      wallEndY: Integer; // if we stuck to a wall, this is where wall ends
+
+      //k8: sorry, i have to emulate virtual methods this way, 'cause i haet `Object`
+      procedure thinkerBloodAndWater ();
+      procedure thinkerSpark ();
+     procedure thinkerBubble ();
+
+      procedure findFloor (force: Boolean=false); // this updates `floorY` if forced or Unknown
+      procedure findCeiling (force: Boolean=false); // this updates `ceilingY` if forced or Unknown
+
+      procedure freeze (); inline; // remove velocities and acceleration
+      procedure sleep (); inline; // switch to sleep mode
+
+      function checkAirStreams (): Boolean; // `true`: affected by air stream
+
+      function alive (): Boolean; inline;
+      procedure die (); inline;
+      procedure think (); inline;
+    end;
+
+    TOnceAnim = record
+      AnimType:   Byte;
+      x, y:       Integer;
+      oldX, oldY: Integer;
+      Animation:  TAnimation;
+    end;
+
+  var (* private state *)
+    Particles: array of TParticle = nil;
+    OnceAnims: array of TOnceAnim = nil;
+
 implementation
 
 uses
-  g_map, g_panel, g_basic, Math, e_graphics, GL, GLExt,
+  {$INCLUDE ../nogl/noGLuses.inc}
+  g_map, g_panel, g_basic, Math, e_graphics,
   g_options, g_console, SysUtils, g_triggers, MAPDEF,
   g_game, g_language, g_net, utils, xprofiler;
 
@@ -81,71 +144,7 @@ uses
 const
   Unknown = Integer($7fffffff);
 
-
-type
-  TPartType = (Blood, Spark, Bubbles, Water);
-  TPartState = (Free, Normal, Stuck, Sleeping);
-  TFloorType = (Wall, LiquidIn, LiquidOut);
-    // Wall: floorY is just before floor
-    // LiquidIn: floorY is liquid *start* (i.e. just in a liquid)
-    // LiquidOut: floorY is liquid *end* (i.e. just out of a liquid)
-  TEnvType = (EAir, ELiquid, EWall); // where particle is now
-
-  // note: this MUST be record, so we can keep it in
-  // dynamic array and has sequential memory access pattern
-  PParticle = ^TParticle;
-  TParticle = record
-    x, y: Integer;
-    velX, velY: Single;
-    accelX, accelY: Single;
-    red, green, blue: Byte;
-    alpha: Byte;
-    time, liveTime: Word;
-    state: TPartState;
-    particleType: TPartType;
-    offsetX, offsetY: ShortInt;
-    // for water
-    stickDX: Integer; // STATE_STICK: -1,1: stuck to a wall; 0: stuck to ceiling
-    justSticked: Boolean; // not used
-    floorY: Integer; // actually, floor-1; `Unknown`: unknown
-    floorType: TFloorType;
-    env: TEnvType; // where particle is now
-    ceilingY: Integer; // actually, ceiling+1; `Unknown`: unknown
-    wallEndY: Integer; // if we stuck to a wall, this is where wall ends
-    // for all
-    onGround: Boolean;
-    awaken: Boolean;
-    stickEY: Integer;
-
-    //k8: sorry, i have to emulate virtual methods this way, 'cause i haet `Object`
-    procedure thinkerBloodAndWater ();
-    procedure thinkerSpark ();
-    procedure thinkerBubble ();
-
-    procedure findFloor (force: Boolean=false); // this updates `floorY` if forced or Unknown
-    procedure findCeiling (force: Boolean=false); // this updates `ceilingY` if forced or Unknown
-
-    procedure freeze (); inline; // remove velocities and acceleration
-    procedure sleep (); inline; // switch to sleep mode
-
-    function isSleeping (): Boolean; inline;
-    procedure awake (); inline;
-
-    function alive (): Boolean; inline;
-    procedure die (); inline;
-    procedure think (); inline;
-  end;
-
-  TOnceAnim = record
-    AnimType:   Byte;
-    x, y:       Integer;
-    Animation:  TAnimation;
-  end;
-
-
 var
-  Particles: array of TParticle = nil;
-  OnceAnims: array of TOnceAnim = nil;
   MaxParticles: Integer = 0;
   CurrentParticle: Integer = 0;
   // awakeMap has one bit for each map grid cell; on g_Mark,
@@ -155,13 +154,56 @@ var
   awakeMapH: Integer = -1;
   awakeMapW: Integer = -1;
   awakeMinX, awakeMinY: Integer;
+  awakeDirty: Boolean = false;
+  {$IF DEFINED(D2F_DEBUG_PART_AWAKE)}
+  awakeMapHlm: packed array of LongWord = nil;
+  {$ENDIF}
+
+
+// ////////////////////////////////////////////////////////////////////////// //
+function awmIsSetHolmes (x, y: Integer): Boolean; inline;
+begin
+{$IF DEFINED(D2F_DEBUG_PART_AWAKE)}
+  if (Length(awakeMapHlm) = 0) then begin result := false; exit; end;
+  x := (x-awakeMinX) div mapGrid.tileSize;
+  y := (y-awakeMinY) div mapGrid.tileSize;
+  if (x >= 0) and (y >= 0) and (x div 32 < awakeMapW) and (y < awakeMapH) then
+  begin
+    if (y*awakeMapW+x div 32 < Length(awakeMapHlm)) then
+    begin
+      result := ((awakeMapHlm[y*awakeMapW+x div 32] and (LongWord(1) shl (x mod 32))) <> 0);
+    end
+    else
+    begin
+      result := false;
+    end;
+  end
+  else
+  begin
+    result := false;
+  end;
+{$ELSE}
+  result := false;
+{$ENDIF}
+end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
 // HACK! using mapgrid
 procedure awmClear (); inline;
 begin
-  if (awakeMapW > 0) then FillDWord(awakeMap[0], Length(awakeMap), 0);
+  {$IF DEFINED(D2F_DEBUG_PART_AWAKE)}
+  if (Length(awakeMap) > 0) then
+  begin
+    if (Length(awakeMapHlm) <> Length(awakeMap)) then SetLength(awakeMapHlm, Length(awakeMap));
+    Move(awakeMap[0], awakeMapHlm[0], Length(awakeMap)*sizeof(awakeMap[0]));
+  end;
+  {$ENDIF}
+  if awakeDirty and (awakeMapW > 0) then
+  begin
+    FillDWord(awakeMap[0], Length(awakeMap), 0);
+    awakeDirty := false;
+  end;
 end;
 
 
@@ -174,9 +216,14 @@ begin
   awakeMinX := mapGrid.gridX0;
   awakeMinY := mapGrid.gridY0;
   SetLength(awakeMap, awakeMapW*awakeMapH);
-  {$IF DEFINED(D2F_DEBUG)}
-  e_LogWritefln('particle awake map: %sx%s (for grid of size %sx%s)', [awakeMapW, awakeMapH, mapGrid.gridWidth, mapGrid.gridHeight]);
+  {$IF DEFINED(D2F_DEBUG_PART_AWAKE)}
+  SetLength(awakeMapHlm, awakeMapW*awakeMapH);
+  FillDWord(awakeMapHlm[0], Length(awakeMapHlm), 0);
   {$ENDIF}
+  //{$IF DEFINED(D2F_DEBUG)}
+  e_LogWritefln('particle awake map: %sx%s (for grid of size %sx%s)', [awakeMapW, awakeMapH, mapGrid.gridWidth, mapGrid.gridHeight]);
+  //{$ENDIF}
+  awakeDirty := true;
   awmClear();
 end;
 
@@ -212,42 +259,64 @@ begin
     {$ENDIF}
     v := @awakeMap[y*awakeMapW+x div 32];
     v^ := v^ or (LongWord(1) shl (x mod 32));
+    awakeDirty := true;
   end;
 end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
-function TParticle.alive (): Boolean; inline; begin result := (state <> TPartState.Free); end;
-procedure TParticle.die (); inline; begin state := TPartState.Free; end;
-
-function TParticle.isSleeping (): Boolean; inline;
+// st: set mark
+// t: mark type
+// currently unused
+procedure g_Mark (x, y, Width, Height: Integer; t: Byte; st: Boolean=true);
+const Extrude = 1;
+var
+  dx, dy, ex, ey: Integer;
+  v: PLongWord;
 begin
-  result := alive and (onGround or (not justSticked and (state = TPartState.Stuck)));
-end;
+  if (not gpart_dbg_enabled) or (not gpart_dbg_phys_enabled) then exit;
+  if (awakeMapW < 1) or (awakeMapH < 1) then exit;
 
-procedure TParticle.awake (); inline;
-begin
-  if {alive and} (onGround or (not justSticked and (state = TPartState.Stuck))) then
+  if (Width < 1) or (Height < 1) then exit;
+
+  // make some border, so we'll hit particles around the panel
+  ex := x+Width+Extrude-1-awakeMinX;
+  ey := y+Height+Extrude-1-awakeMinY;
+  x := (x-Extrude)-awakeMinX;
+  y := (y-Extrude)-awakeMinY;
+
+  x := x div mapGrid.tileSize;
+  y := y div mapGrid.tileSize;
+  ex := ex div mapGrid.tileSize;
+  ey := ey div mapGrid.tileSize;
+
+  // has something to do?
+  if (ex < 0) or (ey < 0) or (x >= awakeMapW*32) or (y >= awakeMapH) then exit;
+  if (x < 0) then x := 0;
+  if (y < 0) then y := 0;
+  if (ex >= awakeMapW*32) then ex := awakeMapW*32-1;
+  if (ey >= awakeMapH) then ey := awakeMapH;
+
+  awakeDirty := true;
+  for dy := y to ey do
   begin
-    // wakeup this particle
-    {
-    if (part.ParticleType = PARTICLE_SPARK) then
-    begin
-      e_LogWritefln('waking up particle of type %s; justSticked=%s; onGround=%s; VelY=%s; AccelY=%s', [part.ParticleType, part.justSticked, part.onGround, part.VelY, part.AccelY]);
-    end;
-    }
-    justSticked := true; // so sticked state will be re-evaluated
-    if onGround then
+    for dx := x to ex do
     begin
-      if (velY = 0) then velY := 0.1;
-      if (accelY = 0) then accelY := 0.5;
+      {$IF DEFINED(D2F_DEBUG)}
+      assert((dx >= 0) and (dy >= 0) and (dx div 32 < awakeMapW) and (dy < awakeMapH));
+      assert(dy*awakeMapW+dx div 32 < Length(awakeMap));
+      {$ENDIF}
+      v := @awakeMap[dy*awakeMapW+dx div 32];
+      v^ := v^ or (LongWord(1) shl (dx mod 32));
     end;
-    onGround := false; // so onground state will be re-evaluated
-    awaken := true;
   end;
 end;
 
 
+// ////////////////////////////////////////////////////////////////////////// //
+function TParticle.alive (): Boolean; inline; begin result := (state <> TPartState.Free); end;
+procedure TParticle.die (); inline; begin state := TPartState.Free; end;
+
 // remove velocities and acceleration
 procedure TParticle.freeze (); inline;
 begin
@@ -259,11 +328,57 @@ begin
 end;
 
 
+// `true`: affected by air stream
+function TParticle.checkAirStreams (): Boolean;
+var
+  pan: TPanel;
+  r: Integer;
+begin
+  pan := g_Map_PanelAtPoint(x, y, GridTagLift);
+  result := (pan <> nil) and WordBool(pan.PanelType and (PANEL_LIFTUP or PANEL_LIFTDOWN or PANEL_LIFTLEFT or PANEL_LIFTRIGHT));
+  r := Random(3);
+  if result then
+  begin
+    case pan.LiftType of
+      LIFTTYPE_UP:
+      begin
+        if (velY > -1-r) then velY -= 0.8;
+        if (abs(velX) > 0.1) then velX -= velX/10.0;
+        velX += (Random-Random)*0.2;
+        accelY := 0.15;
+      end;
+      LIFTTYPE_DOWN:
+      begin
+        if (velY < 1+r) then velY += 0.8;
+        accelY := 0.15;
+      end;
+      LIFTTYPE_LEFT:
+      begin
+        if (velX > -8-r) then velX -= (8+r) div 2;
+        accelY := 0.15;
+      end;
+      LIFTTYPE_RIGHT:
+      begin
+        if (velX < 8+r) then velX += (8+r) div 2;
+        accelY := 0.15;
+      end;
+      else
+        result := false;
+    end;
+    // awake
+    if result and (state = TPartState.Sleeping) then state := TPartState.Normal;
+  end;
+end;
+
+
 // switch to sleep mode
 procedure TParticle.sleep (); inline;
 begin
-  state := TPartState.Sleeping;
-  freeze();
+  if not checkAirStreams() then
+  begin
+    state := TPartState.Sleeping;
+    freeze();
+  end;
 end;
 
 
@@ -340,7 +455,7 @@ var
   ex: Integer;
 begin
   if (not force) and (ceilingY <> Unknown) then exit;
-  if (nil = g_Map_traceToNearest(x, y, x, g_Map_MinY, GridTagObstacle, @ex, @ceilingY)) then
+  if (nil = g_Map_traceToNearest(x, y, x, g_Map_MinY, GridTagSolid, @ex, @ceilingY)) then
   begin
     ceilingY := g_Map_MinY-2;
   end;
@@ -348,12 +463,60 @@ end;
 
 
 procedure TParticle.think (); inline;
+  procedure awake ();
+  begin
+    if (state = TPartState.Stuck) then
+    begin
+      //writeln('awaking particle at (', x, ',', y, ')');
+      if (stickDX = 0) then
+      begin
+        state := TPartState.Normal; // stuck to a ceiling
+      end
+      else
+      begin
+        // stuck to a wall, check if wall is still there
+        if (wallEndY <> Unknown) then
+        begin
+          wallEndY := Unknown;
+          if (g_Map_PanelAtPoint(x+stickDX, y, GridTagObstacle) = nil) then
+          begin
+            // a wall was moved out, start falling
+            state := TPartState.Normal;
+            if (velY = 0) then velY := 0.1;
+            if (accelY = 0) then accelY := 0.5;
+          end;
+        end;
+      end;
+    end
+    else
+    begin
+      state := TPartState.Normal;
+      if (velY = 0) then velY := 0.1;
+      if (accelY = 0) then accelY := 0.5;
+    end;
+    floorY := Unknown;
+    ceilingY := Unknown;
+  end;
+
 begin
+  oldx := x;
+  oldy := y;
   // awake sleeping particle, if necessary
-  if (state = TPartState.Sleeping) and awmIsSet(x, y) then state := TPartState.Normal;
+  if awakeDirty then
+  begin
+    if awmIsSet(x, y) then awake();
+    {
+    case state of
+      TPartState.Sleeping, TPartState.Stuck:
+        if awmIsSet(x, y) then awake();
+      else
+        if (env = TEnvType.EWall) and awmIsSet(x, y) then awake();
+    end;
+    }
+  end;
   case particleType of
     TPartType.Blood, TPartType.Water: thinkerBloodAndWater();
-    //TPartType.Spark: thinkerSpark();
+    TPartType.Spark: thinkerSpark();
     TPartType.Bubbles: thinkerBubble();
   end;
 end;
@@ -374,13 +537,12 @@ procedure TParticle.thinkerBloodAndWater ();
     ex: Integer;
   begin
     state := TPartState.Stuck;
-    if (dX > 0) then stickDX := 1 else stickDX := -1;
+    if (dx > 0) then stickDX := 1 else stickDX := -1;
     freeze();
     // find next floor transition
     findFloor();
     // find `wallEndY`
     mapGrid.traceOrthoRayWhileIn(ex, wallEndY, x+stickDX, y, x+stickDX, floorY+1, (GridTagWall or GridTagDoor or GridTagStep));
-    //if (wallEndY > floorY) then wallEndY := floorY; // just in case
   end;
 
   procedure hitAFloor ();
@@ -399,41 +561,12 @@ procedure TParticle.thinkerBloodAndWater ();
       TPartType.Water: result := (Random(30) = 15);
       else raise Exception.Create('internal error in particle engine: drip');
     end;
-    if result then begin velY := 0.5; accelY := 0.15; end;
-  end;
-
-  // `true`: affected by air stream
-  function checkAirStreams (): Boolean;
-  var
-    pan: TPanel;
-  begin
-    pan := g_Map_PanelAtPoint(x, y, GridTagLift);
-    result := (pan <> nil);
     if result then
     begin
-      if ((pan.PanelType and PANEL_LIFTUP) <> 0) then
-      begin
-        if (velY > -4-Random(3)) then velY -= 0.8;
-        if (abs(velX) > 0.1) then velX -= velX/10.0;
-        velX += (Random-Random)*0.2;
-        accelY := 0.15;
-      end
-      else if ((pan.PanelType and PANEL_LIFTLEFT) <> 0) then
-      begin
-        if (velX > -8-Random(3)) then velX -= 0.8;
-        accelY := 0.15;
-      end
-      else if ((pan.PanelType and PANEL_LIFTRIGHT) <> 0) then
-      begin
-        if (velX < 8+Random(3)) then velX += 0.8;
-        accelY := 0.15;
-      end
-      else
-      begin
-        result := false;
-      end;
-      // awake
-      if result and (state = TPartState.Sleeping) then state := TPartState.Normal;
+      velY := 0.5;
+      accelY := 0.15;
+      // if we're falling from ceiling, switch to normal mode
+      if (state = TPartState.Stuck) and (stickDX = 0) then state := TPartState.Normal;
     end;
   end;
 
@@ -448,7 +581,7 @@ procedure TParticle.thinkerBloodAndWater ();
   procedure applyGravity (inLiquid: Boolean);
   begin
     state := TPartState.Normal;
-    if (inLiquid) then
+    if inLiquid then
     begin
       velY := 0.5;
       accelY := 0.15;
@@ -461,16 +594,23 @@ procedure TParticle.thinkerBloodAndWater ();
   end;
 
 label
-  _done;
+  _done, _gravityagain, _stuckagain;
 var
   pan: TPanel;
-  dX, dY: SmallInt;
+  dx, dy: SmallInt;
   ex, ey: Integer;
+  checkEnv, inAir, inStep: Boolean;
+  floorJustTraced: Boolean;
+  {$IF DEFINED(D2F_DEBUG_FALL_MPLAT)}
+  oldFloorY: Integer;
+  {$ENDIF}
 begin
+  if not gpart_dbg_phys_enabled then begin x += round(velX); y += round(velY); goto _done; end;
+
   if gAdvBlood then
   begin
-    // still check for air streams when sleeping
-    if (state = TPartState.Sleeping) then begin checkAirStreams(); goto _done; end; // so blood will dissolve
+    // still check for air streams when sleeping (no)
+    if (state = TPartState.Sleeping) then begin {checkAirStreams();} goto _done; end; // so blood will dissolve
 
     // process stuck particles
     if (state = TPartState.Stuck) then
@@ -479,7 +619,7 @@ begin
       if (stickDX = 0) then
       begin
         // yeah, stuck to a ceiling
-        assert(ceilingY <> Unknown);
+        if (ceilingY = Unknown) then findCeiling();
         // dropped from a ceiling?
         if (y > ceilingY) then
         begin
@@ -497,15 +637,30 @@ begin
       else
       begin
         // stuck to a wall
-        assert(wallEndY <> Unknown);
+        if (wallEndY = Unknown) then
+        begin
+          // this can happen if mplat was moved out; find new `wallEndY`
+          findFloor(true); // force trace, just in case
+          if (floorType = TFloorType.LiquidOut) then env := TEnvType.ELiquid else env := TEnvType.EAir;
+          mapGrid.traceOrthoRayWhileIn(ex, wallEndY, x+stickDX, y, x+stickDX, floorY+1, (GridTagWall or GridTagDoor or GridTagStep));
+        end;
+       _stuckagain:
         // floor transition?
-        if (y = floorY) then
+        if (wallEndY <= floorY) and (y >= floorY) then
         begin
+          y := floorY;
           case floorType of
             TFloorType.Wall: // hit the ground
               begin
-                sleep();
-                goto _done; // nothing to do anymore
+                // check if our ground wasn't moved since the last scan
+                findFloor(true); // force trace
+                if (y = floorY) then
+                begin
+                  sleep();
+                  goto _done; // nothing to do anymore
+                end;
+                // otherwise, do it again
+                goto _stuckagain;
               end;
             TFloorType.LiquidIn: // entering the liquid
               begin
@@ -521,9 +676,10 @@ begin
           end;
         end;
         // wall transition?
-        if (y = wallEndY) then
+        if (floorY <= wallEndY) and (y >= wallEndY) then
         begin
           // just unstuck from the wall, switch to freefall mode
+          y := wallEndY;
           freefall();
         end
         else
@@ -536,20 +692,31 @@ begin
     end;
 
     // it is important to have it here
-    dX := round(velX);
-    dY := round(velY);
+    dx := round(velX);
+    dy := round(velY);
+
+    inAir := checkAirStreams();
 
     // gravity, if not stuck
     if (state <> TPartState.Stuck) and (abs(velX) < 0.1) and (abs(velY) < 0.1) then
     begin
-      if (floorY = Unknown) then findFloor();
+      floorJustTraced := (floorY = Unknown);
+      if floorJustTraced then findFloor();
+     _gravityagain:
       // floor transition?
       if (y = floorY) then
       begin
         case floorType of
           TFloorType.Wall: // hit the ground
             begin
-              // nothing to do
+              // check if our ground wasn't moved since the last scan
+              if not floorJustTraced then
+              begin
+                findFloor(true); // force trace
+                if (floorType = TFloorType.LiquidOut) then env := TEnvType.ELiquid else env := TEnvType.EAir;
+                if (y <> floorY) then goto _gravityagain;
+              end;
+              // otherwise, nothing to do
             end;
           TFloorType.LiquidIn: // entering the liquid
             begin
@@ -573,64 +740,109 @@ begin
     end;
 
     // trace movement
-    if (dX <> 0) then
+    if (dx <> 0) then
     begin
       // has some horizontal velocity
-      pan := g_Map_traceToNearest(x, y, x+dX, y+dY, GridTagObstacle, @ex, @ey);
-      if (x <> ex) then begin floorY := Unknown; ceilingY := Unknown; end; // dunno yet
+      inStep := False;
+      pan := g_Map_traceToNearest(x, y, x+dx, y+dy, GridTagSolid, @ex, @ey);
+      if (pan = nil) and (dy >= 0) then
+      begin
+        // do not stuck inside step
+        if g_Map_traceToNearest(x, y, x, y, GridTagStep, nil, nil) = nil then
+          // check for step panel below
+          pan := g_Map_traceToNearest(x, y, x, y+dy, GridTagStep, nil, @ey);
+        inStep := pan <> nil;
+        if inStep then
+        begin
+          // stick to panel edges
+          if ex < pan.X then
+            ex := pan.X
+          else if ex > pan.X + pan.Width - 1 then
+            ex := pan.X + pan.Width - 1;
+        end;
+      end;
+      checkEnv := (x <> ex);
       x := ex;
       y := ey;
-      if (x < g_Map_MinX) or (x > g_Map_MaxX) then begin die(); exit; end;
-      if (pan <> nil) then
+      if checkEnv then
       begin
-        // we stuck
-        // the only case when we can have both ceiling and wall is corner; stick to wall in this case
+        // dunno yet
+        floorY := Unknown;
+        ceilingY := Unknown;
         // check environment (air/liquid)
         if (g_Map_PanelAtPoint(x, y, GridTagLiquid) <> nil) then env := TEnvType.ELiquid else env := TEnvType.EAir;
-        // check if we stuck to a wall
-        if (dX < 0) then dX := -1 else dX := 1;
-        if (g_Map_PanelAtPoint(x+dX, y, GridTagObstacle) <> nil) then
-        begin
-          // stuck to a wall
-          stickToWall(dX);
-        end
+      end;
+      if (pan <> nil) then
+      begin
+        if inStep then
+          stickToWall(dx)
         else
         begin
-          // stuck to a ceiling
-          stickToCeiling();
+          // we stuck
+          // the only case when we can have both ceiling and wall is corner; stick to wall in this case
+          // check if we stuck to a wall
+          if (dx < 0) then dx := -1 else dx := 1;
+          if (g_Map_PanelAtPoint(x+dx, y, GridTagSolid) <> nil) then
+          begin
+            // stuck to a wall
+            stickToWall(dx);
+          end
+          else
+          begin
+            // stuck to a ceiling
+            stickToCeiling();
+          end;
         end;
       end;
     end
-    else if (dY <> 0) then
+    else if (dy <> 0) then
     begin
       // has only vertical velocity
-      if (dY < 0) then
+      if (dy < 0) then
       begin
         // flying up
         if (ceilingY = Unknown) then findCeiling(); // need to do this anyway
-        y += dY;
+        y += dy;
         if (y <= ceilingY) then begin y := ceilingY; stickToCeiling(); end; // oops, hit a ceiling
-        // environmend didn't changed
+        // environment didn't changed
       end
       else
       begin
-        while (dY > 0) do
+        while (dy > 0) do
         begin
           // falling down
-          if (floorY = Unknown) then findFloor(); // need to do this anyway
-          y += dY;
+          floorJustTraced := (floorY = Unknown);
+          if floorJustTraced then findFloor();
+          if (floorType = TFloorType.LiquidOut) then env := TEnvType.ELiquid else env := TEnvType.EAir;
+          y += dy;
           //e_LogWritefln('floorY=%s; newy=%s; dY=%s; floorType=%s', [floorY, y, dY, floorType]);
           if (y >= floorY) then
           begin
             // floor transition
-            dY := y-floorY;
+            dy := y-floorY;
             y := floorY;
             //e_LogWritefln('  HIT FLOORY: floorY=%s; newy=%s; dY=%s; floorType=%s', [floorY, y, dY, floorType]);
             case floorType of
               TFloorType.Wall: // hit the ground
                 begin
-                  // environmend didn't changed
-                  hitAFloor();
+                  // check if our ground wasn't moved since the last scan
+                  if not floorJustTraced then
+                  begin
+                    {$IF DEFINED(D2F_DEBUG_FALL_MPLAT)}
+                    oldFloorY := floorY;
+                    {$ENDIF}
+                    findFloor(true); // force trace
+                    {$IF DEFINED(D2F_DEBUG_FALL_MPLAT)}
+                    if (floorY <> oldFloorY) then
+                    begin
+                      e_LogWritefln('force rescanning vpart at (%s,%s); oldFloorY=%s; floorY=%s', [x, y, oldFloorY, floorY]);
+                    end;
+                    {$ENDIF}
+                    if (floorType = TFloorType.LiquidOut) then env := TEnvType.ELiquid else env := TEnvType.EAir;
+                    if (y <> floorY) then continue;
+                  end;
+                  // environment didn't changed
+                  if not inAir then hitAFloor();
                   break; // done with vertical movement
                 end;
               TFloorType.LiquidIn: // entering the liquid
@@ -648,7 +860,7 @@ begin
                   findFloor(true); // force rescan
                   if (floorType = TFloorType.Wall) and (floorY = y) then
                   begin
-                    hitAFloor();
+                    if not inAir then hitAFloor();
                     break; // done with vertical movement
                   end;
                 end;
@@ -665,15 +877,16 @@ begin
   else
   begin
     // simple blood
-    dX := Round(velX);
-    dY := Round(velY);
-    y += dY;
-    x += dX;
-    if (x > g_Map_MaxX) or (y > g_Map_MaxY) or (x < g_Map_MinX) or (y < g_Map_MinY) then begin die(); exit; end;
+    dx := round(velX);
+    dy := round(velY);
+    y += dy;
+    x += dx;
     if (g_Map_PanelAtPoint(x, y, GridTagObstacle) <> nil) then begin die(); exit; end;
   end;
 
 _done:
+  if (x < g_Map_MinX) or (y < g_Map_MinY) or (x > g_Map_MaxX) or (y > g_Map_MaxY) then begin die(); end;
+
   velX += accelX;
   velY += accelY;
 
@@ -682,25 +895,37 @@ _done:
   begin
     if (env = TEnvType.ELiquid) then
     begin
-      time += 1;
+      if waitTime > 0 then
+        waitTime -= 1
+      else
+        time += 1;
       if (liveTime <= 0) then begin die(); exit; end;
       ex := 255-trunc(255.0*time/liveTime);
-      if (ex >= 250) then begin die(); exit; end;
-      if (ex < 0) then ex := 0;
+      if (ex <= 10) then begin die(); exit; end;
+      if (ex > 250) then ex := 255;
       alpha := Byte(ex);
     end;
   end
   else
   begin
-    // water will disappear in water (?)
-    if (env = TEnvType.ELiquid) then die();
-    time += 1;
+    // water will disappear in any liquid
+    if (env = TEnvType.ELiquid) then begin die(); exit; end;
+    if waitTime > 0 then
+      waitTime -= 1
+    else
+      time += 1;
+    // dry water
+    if (liveTime <= 0) then begin die(); exit; end;
+    ex := 255-trunc(255.0*time/liveTime);
+    if (ex <= 10) then begin die(); exit; end;
+    if (ex > 250) then ex := 255;
+    alpha := Byte(ex);
   end;
 end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
-procedure g_GFX_SparkVel (fX, fY: Integer; count: Word; VX, VY: Integer; devX, devY: Byte); forward;
+procedure g_GFX_SparkVel (fX, fY: Integer; count: Word; vx, vy: Integer; devX, devY: Byte); forward;
 
 procedure g_GFX_Blood (fX, fY: Integer; count: Word; vx, vy: Integer;
                        devX, devY: Word; cr, cg, cb: Byte; kind: Byte = BLOOD_NORMAL);
@@ -727,12 +952,17 @@ var
   crnd: Integer;
   pan: TPanel;
 begin
-  if not gpart_dbg_enabled then Exit;
+  if not gpart_dbg_enabled then exit;
 
   if (kind = BLOOD_SPARKS) then
   begin
-    g_GFX_SparkVel(fX, fY, 2+Random(2), -VX div 2, -VY div 2, devX, devY);
+    g_GFX_SparkVel(fX, fY, 2+Random(2), -vx div 2, -vy div 2, devX, devY);
     exit;
+  end
+  else if (kind = BLOOD_CSPARKS) OR (kind = BLOOD_COMBINE) then
+  begin
+    g_GFX_SparkVel(fX, fY, count, -vx div 2, -vy div 2, devX, devY);
+    if kind <> BLOOD_COMBINE then exit
   end;
 
   l := Length(Particles);
@@ -750,16 +980,18 @@ begin
     begin
       x := fX-devX1+Random(devX2);
       y := fY-devY1+Random(devY2);
+      oldx := x;
+      oldy := y;
 
       // check for level bounds
       if (x < g_Map_MinX) or (y < g_Map_MinY) or (x > g_Map_MaxX) or (y > g_Map_MaxY) then continue;
 
       // in what environment we are starting in?
-      pan := g_Map_PanelAtPoint(x, y, (GridTagObstacle or GridTagLiquid));
+      pan := g_Map_PanelAtPoint(x, y, (GridTagSolid or GridTagLiquid));
       if (pan <> nil) then
       begin
         // either in a wall, or in a liquid
-        if ((pan.tag and GridTagObstacle) <> 0) then continue; // don't spawn in walls
+        if ((pan.tag and GridTagSolid) <> 0) then continue; // don't spawn in walls
         env := TEnvType.ELiquid;
       end
       else
@@ -789,6 +1021,7 @@ begin
       state := TPartState.Normal;
       time := 0;
       liveTime := 120+Random(40);
+      waitTime := 20;
       floorY := Unknown;
       ceilingY := Unknown;
     end;
@@ -806,7 +1039,7 @@ var
   l: Integer;
   pan: TPanel;
 begin
-  if not gpart_dbg_enabled then Exit;
+  if not gpart_dbg_enabled then exit;
 
   l := Length(Particles);
   if (l = 0) then exit;
@@ -847,22 +1080,25 @@ begin
         accelY := 0.8;
       end;
 
+      oldx := x;
+      oldy := y;
+
       // check for level bounds
       if (x < g_Map_MinX) or (y < g_Map_MinY) or (x > g_Map_MaxX) or (y > g_Map_MaxY) then continue;
 
-      // in what environment we are starting in?
-      pan := g_Map_PanelAtPoint(x, y, (GridTagObstacle or GridTagLiquid));
-      if (pan <> nil) then
+      // this hack will allow water spawned in water to fly out
+      // it can happen when player fell from a huge height (see "DOOM2D.WAD:\MAP03", for example)
+      if (fVelY >= 0) then
       begin
-        // either in a wall, or in a liquid
-        //if ((pan.tag and GridTagObstacle) <> 0) then continue; // don't spawn in walls
-        //env := TEnvType.ELiquid;
-        continue;
+        // in what environment we are starting in?
+        pan := g_Map_PanelAtPoint(x, y, (GridTagObstacle or GridTagLiquid));
       end
       else
       begin
-        env := TEnvType.EAir;
+        pan := g_Map_PanelAtPoint(x, y, GridTagObstacle);
       end;
+      if (pan <> nil) then continue;
+      env := TEnvType.EAir;
 
       // color
       case color of
@@ -915,6 +1151,7 @@ begin
       state := TPartState.Normal;
       time := 0;
       liveTime := 60+Random(60);
+      waitTime := 120;
       floorY := Unknown;
       ceilingY := Unknown;
     end;
@@ -933,14 +1170,14 @@ end;
 // ////////////////////////////////////////////////////////////////////////// //
 procedure TParticle.thinkerBubble ();
 var
-  dY: Integer;
+  dy: Integer;
 begin
-  dY := round(velY);
+  dy := round(velY);
 
-  if (dY <> 0) then
+  if (dy <> 0) then
   begin
-    y += dY;
-    if (dY < 0) then
+    y += dy;
+    if (dy < 0) then
     begin
       if (y <= ceilingY) then begin die(); exit; end;
     end
@@ -953,7 +1190,10 @@ begin
 
   if (velY > -4) then velY += accelY;
 
-  time += 1;
+  if waitTime > 0 then
+    waitTime -= 1
+  else
+    time += 1;
 end;
 
 
@@ -968,7 +1208,7 @@ var
   nptr, ptr: Boolean;
   {$ENDIF}
 begin
-  if not gpart_dbg_enabled then Exit;
+  if not gpart_dbg_enabled then exit;
 
   l := Length(Particles);
   if (l = 0) then exit;
@@ -985,6 +1225,8 @@ begin
     begin
       x := fX-devX1+Random(devX2);
       y := fY-devY1+Random(devY2);
+      oldx := x;
+      oldy := y;
 
       // check for level bounds
       if (x < g_Map_MinX) or (y < g_Map_MinY) or (x > g_Map_MaxX) or (y > g_Map_MaxY) then continue;
@@ -999,14 +1241,14 @@ begin
       // tracer will return `false` if we started outside of the liquid
 
       {$IF DEFINED(D2F_DEBUG_BUBBLES)}
-      stt := curTimeMicro();
+      stt := getTimeMicro();
       ptr := mapGrid.traceOrthoRayWhileIn(liquidx, liquidTopY, x, y, x, 0, GridTagWater or GridTagAcid1 or GridTagAcid2);
-      stt := curTimeMicro()-stt;
+      stt := getTimeMicro()-stt;
       e_LogWritefln('traceOrthoRayWhileIn: time=%s (%s); liquidTopY=%s', [Integer(stt), ptr, liquidTopY]);
       //
-      stt := curTimeMicro();
+      stt := getTimeMicro();
       nptr := g_Map_TraceLiquidNonPrecise(x, y, 0, -8, liquidx, liquidTopY);
-      stt := curTimeMicro()-stt;
+      stt := getTimeMicro()-stt;
       e_LogWritefln('g_Map_TraceLiquidNonPrecise: time=%s (%s); liquidTopY=%s', [Integer(stt), nptr, liquidTopY]);
       if not nptr then continue;
       {$ELSE}
@@ -1028,6 +1270,7 @@ begin
       particleType := TPartType.Bubbles;
       time := 0;
       liveTime := 65535;
+      waitTime := 0;
     end;
 
     if (CurrentParticle >= MaxParticles-1) then CurrentParticle := 0 else CurrentParticle += 1;
@@ -1036,355 +1279,81 @@ end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
-function isBlockedAt (x, y: Integer): Boolean; inline;
-begin
-  if not gpart_dbg_phys_enabled then begin result := false; exit; end;
-  result := g_Map_HasAnyPanelAtPoint(x, y, (PANEL_WALL or PANEL_OPENDOOR or PANEL_CLOSEDOOR or PANEL_STEP));
-end;
-
-// ???
-function isWallAt (x, y: Integer): Boolean; inline;
-begin
-  if not gpart_dbg_phys_enabled then begin result := false; exit; end;
-  result := g_Map_HasAnyPanelAtPoint(x, y, (PANEL_WALL or PANEL_STEP));
-end;
-
-function isLiftUpAt (x, y: Integer): Boolean; inline;
-begin
-  if not gpart_dbg_phys_enabled then begin result := false; exit; end;
-  result := g_Map_HasAnyPanelAtPoint(x, y, PANEL_LIFTUP);
-end;
-
-function isLiftDownAt (x, y: Integer): Boolean; inline;
-begin
-  if not gpart_dbg_phys_enabled then begin result := false; exit; end;
-  result := g_Map_HasAnyPanelAtPoint(x, y, PANEL_LIFTDOWN);
-end;
-
-function isLiftLeftAt (x, y: Integer): Boolean; inline;
-begin
-  if not gpart_dbg_phys_enabled then begin result := false; exit; end;
-  result := g_Map_HasAnyPanelAtPoint(x, y, PANEL_LIFTLEFT);
-end;
-
-function isLiftRightAt (x, y: Integer): Boolean; inline;
-begin
-  if not gpart_dbg_phys_enabled then begin result := false; exit; end;
-  result := g_Map_HasAnyPanelAtPoint(x, y, PANEL_LIFTRIGHT);
-end;
-
-function isLiquidAt (x, y: Integer): Boolean; inline;
-begin
-  if not gpart_dbg_phys_enabled then begin result := false; exit; end;
-  result := g_Map_HasAnyPanelAtPoint(x, y, (PANEL_WATER or PANEL_ACID1 or PANEL_ACID2));
-end;
-
-function isAnythingAt (x, y: Integer): Boolean; inline;
-begin
-  if not gpart_dbg_phys_enabled then begin result := false; exit; end;
-  result := g_Map_HasAnyPanelAtPoint(x, y, (PANEL_WALL or PANEL_CLOSEDOOR or PANEL_OPENDOOR or PANEL_WATER or PANEL_ACID1 or PANEL_ACID2 or PANEL_STEP or PANEL_LIFTUP or PANEL_LIFTDOWN or PANEL_LIFTLEFT or PANEL_LIFTRIGHT));
-end;
-
-
-// ////////////////////////////////////////////////////////////////////////// //
-(*
-procedure TParticle.thinkerWater ();
+procedure TParticle.thinkerSpark ();
+label
+  _done;
 var
-  dX, dY: SmallInt;
+  dx, dy: SmallInt;
   pan: TPanel;
   ex, ey: Integer;
 begin
-  //TODO: trace wall end when water becomes stick
-  if (state = TPartState.Stuck) and (Random(30) = 15) then
-  begin // Ñòåêàåò/îòëèïàåò
-    velY := 0.5;
-    accelY := 0.15;
-    if (stickDX = 0) then
-    begin
-      // no walls around, drop
-      state := TPartState.Normal;
-    end
-    else
-    begin
-      if justSticked then
-      begin
-        if not mapGrid.traceOrthoRayWhileIn(ex, ey, x+stickDX, y, x+stickDX, mapGrid.gridY0+mapGrid.gridHeight, GridTagWall or GridTagDoor or GridTagStep) then
-        begin
-           // îòëèïëà
-          state := TPartState.Normal;
-          //e_LogWritefln('juststicked unsticked: X=%s; X+stickDX=%s; stickDX=%s; Y=%s', [X, X+stickDX, stickDX, Y]);
-        end
-        else
-        begin
-          stickEY := ey+1;
-          justSticked := false;
-          if (nil <> g_Map_traceToNearest(x, y, x, stickEY, (GridTagWall or GridTagDoor or GridTagStep or GridTagAcid1 or GridTagAcid2 or GridTagWater), @ex, @ey)) then
-          begin
-            if (ey > stickEY) then stickEY := ey-1;
-          end;
-          //e_LogWritefln('juststicked: X=%s; X+stickDX=%s; stickDX=%s; Y=%s; stickEY=%s', [X, X+stickDX, stickDX, Y, stickEY]);
-        end;
-      end
-      else
-      begin
-        if (y >= stickEY) then state := TPartState.Normal;
-      end;
-      //if not g_Map_CollidePanel(X-1, Y-1, 3, 3, (PANEL_STEP or PANEL_WALL or PANEL_OPENDOOR or PANEL_CLOSEDOOR))
-    end;
-    exit;
-  end;
-
-  pan := g_Map_PanelAtPoint(x, y, (GridTagAcid1 or GridTagAcid2 or GridTagWater or GridTagLift));
-  if (pan <> nil) then
-  begin
-    if ((pan.tag and (GridTagAcid1 or GridTagAcid2 or GridTagWater)) <> 0) then begin die(); exit; end;
-    if ((pan.PanelType and PANEL_LIFTUP) <> 0) then
-    begin
-      if (velY > -4-Random(3)) then velY -= 0.8;
-      if (Abs(velX) > 0.1) then velX -= velX/10.0;
-      velX += (Random-Random)*0.2;
-      accelY := 0.15;
-    end;
-    if ((pan.PanelType and PANEL_LIFTLEFT) <> 0) then
-    begin
-      if (velX > -8-Random(3)) then velX -= 0.8;
-      accelY := 0.15;
-    end;
-    if ((pan.PanelType and PANEL_LIFTRIGHT) <> 0) then
-    begin
-      if (velX < 8+Random(3)) then velX += 0.8;
-      accelY := 0.15;
-    end;
-  end;
-
-  dX := Round(velX);
-  dY := Round(velY);
-
-  if (state <> TPartState.Stuck) and (Abs(velX) < 0.1) and (Abs(velY) < 0.1) then
-  begin
-    // Âèñèò â âîçäóõå - êàïàåò
-    if (nil = g_Map_traceToNearest(x, y-1, x, y+1, (GridTagWall or GridTagDoor or GridTagStep or GridTagAcid1 or GridTagAcid2 or GridTagWater), @ex, @ey)) then
-    begin
-      velY := 0.8;
-      accelY := 0.5;
-      state := TPartState.Normal;
-    end;
-  end;
-
-  // horizontal
-  if (dX <> 0) then
-  begin
-    pan := g_Map_traceToNearest(x, y, x+dX, y, (GridTagWall or GridTagDoor or GridTagStep or GridTagAcid1 or GridTagAcid2 or GridTagWater), @ex, @ey);
-    if (x <> ex) then onGround := false;
-    x := ex;
-    // free to ride?
-    if (pan <> nil) then
-    begin
-      // nope
-      if (dY > 0) and ((pan.tag and (GridTagAcid1 or GridTagAcid2 or GridTagWater)) <> 0) then begin die(); exit; end;
-      // Ñòåíà/äâåðü?
-      if ((pan.tag and (GridTagWall or GridTagDoor or GridTagStep)) <> 0) then
-      begin
-        velX := 0;
-        velY := 0;
-        accelX := 0;
-        accelY := 0;
-        state := TPartState.Stuck;
-        justSticked := true;
-        if (dX > 0) then stickDX := 1 else stickDX := -1;
-      end;
-    end;
-    if (x < 0) or (x >= gMapInfo.Width) then begin die(); exit; end;
-  end;
-  // vertical
-  if (dY <> 0) then
-  begin
-    if (dY < 0) or not onGround then
-    begin
-      pan := g_Map_traceToNearest(x, y, x, y+dY, (GridTagWall or GridTagDoor or GridTagStep or GridTagAcid1 or GridTagAcid2 or GridTagWater), @ex, @ey);
-      y := ey;
-      // free to ride?
-      if (pan <> nil) then
-      begin
-        // nope
-        if (dY > 0) and ((pan.tag and (GridTagAcid1 or GridTagAcid2 or GridTagWater)) <> 0) then begin die(); exit; end;
-        // Ñòåíà/äâåðü?
-        if ((pan.tag and (GridTagWall or GridTagDoor or GridTagStep)) <> 0) then
-        begin
-          velX := 0;
-          velY := 0;
-          accelX := 0;
-          accelY := 0;
-          if (dY > 0) and (state <> TPartState.Stuck) then
-          begin
-            state := TPartState.Normal;
-          end
-          else
-          begin
-            state := TPartState.Stuck;
-                 if (g_Map_PanelAtPoint(x-1, y, (GridTagWall or GridTagDoor or GridTagStep)) <> nil) then stickDX := -1
-            else if (g_Map_PanelAtPoint(x+1, y, (GridTagWall or GridTagDoor or GridTagStep)) <> nil) then stickDX := 1
-            else stickDX := 0;
-            justSticked := true;
-          end;
-        end;
-      end;
-      onGround := (velY >= 0) and g_Map_HasAnyPanelAtPoint(x, y+1, (PANEL_WALL or PANEL_CLOSEDOOR or PANEL_STEP));
-    end;
-    if (y < 0) or (y >= gMapInfo.Height) then begin die(); exit; end;
-  end;
-
-  velX += accelX;
-  velY += accelY;
-
-  time += 1;
-end;
-*)
+  if not gpart_dbg_phys_enabled then begin x += round(velX); y += round(velY); goto _done; end;
 
+  dx := round(velX);
+  dy := round(velY);
 
-// ////////////////////////////////////////////////////////////////////////// //
-procedure TParticle.thinkerSpark ();
-var
-  dX, dY: SmallInt;
-  {$IF not DEFINED(D2F_NEW_SPARK_THINKER)}
-  b: Integer;
-  s: ShortInt;
-  {$ELSE}
-  pan: TPanel;
-  ex, ey: Integer;
-  {$ENDIF}
-begin
-  dX := Round(velX);
-  dY := Round(velY);
+  //writeln('spark0: pos=(', x, ',', y, '); delta=(', dx, ',', dy, '); state=', state, '; ceilingY=', ceilingY, '; floorY=', floorY);
 
-  {$IF DEFINED(D2F_NEW_SPARK_THINKER)}
+  // apply gravity
   if (abs(velX) < 0.1) and (abs(velY) < 0.1) then
   begin
-    pan := g_Map_traceToNearest(x, y-1, x, y+1, (GridTagWall or GridTagDoor or GridTagStep or GridTagAcid1 or GridTagAcid2 or GridTagWater), @ex, @ey);
-  end;
-  {$ELSE}
-  if (abs(velX) < 0.1) and (abs(velY) < 0.1) and
-     (not isBlockedAt(x, y-1) {ByteBool(gCollideMap[Y-1, X] and MARK_BLOCKED)}) and
-     (not isBlockedAt(x, y) {ByteBool(gCollideMap[Y, X] and MARK_BLOCKED)}) and
-     (not isBlockedAt(x, y+1) {ByteBool(gCollideMap[Y+1, X] and MARK_BLOCKED)}) then
-  begin // Âèñèò â âîçäóõå
     velY := 0.8;
     accelY := 0.5;
   end;
-  {$ENDIF}
 
-  if (dX <> 0) then
+  // flying
+  if (dx <> 0) then
   begin
-    {$IF DEFINED(D2F_NEW_SPARK_THINKER)}
-    pan := g_Map_traceToNearest(x, y, x+dX, y, (GridTagWall or GridTagDoor or GridTagStep or GridTagAcid1 or GridTagAcid2 or GridTagWater), @ex, @ey);
-    //e_WriteLog(Format('spark h-trace: (%d,%d)-(%d,%d); dx=%d; end=(%d,%d); hit=%d', [X, Y, X+dX, Y, dX, ex, ey, Integer(pan <> nil)]), MSG_NOTIFY);
-    if (x <> ex) then onGround := false;
+    // has some horizontal velocity
+    pan := g_Map_traceToNearest(x, y, x+dx, y+dy, (GridTagSolid or GridTagLiquid), @ex, @ey);
+    if (x <> ex) then begin floorY := Unknown; ceilingY := Unknown; end; // dunno yet
     x := ex;
-    // free to ride?
+    y := ey;
     if (pan <> nil) then
     begin
-      // nope
-      if ((pan.tag and (GridTagAcid1 or GridTagAcid2 or GridTagWater)) <> 0) then begin die(); exit; end;
+      if ((pan.tag and GridTagLiquid) <> 0) then begin die(); exit; end; // die in liquid
+      // hit the wall; falling down vertically
       velX := 0;
       accelX := 0;
     end;
-    if (x < 0) or (x >= gMapInfo.Width) then begin die(); exit; end;
-    {$ELSE}
-    if (dX > 0) then s := 1 else s := -1;
-    dX := abs(dX);
-    for b := 1 to dX do
-    begin
-      if (x+s >= gMapInfo.Width) or (x+s <= 0) then begin die(); break; end;
-      //c := gCollideMap[Y, X+s];
-      if isBlockedAt(x+s, y) {ByteBool(c and MARK_BLOCKED)} then
-        begin // Ñòåíà/äâåðü - ïàäàåò âåðòèêàëüíî
-          velX := 0;
-          accelX := 0;
-          Break;
-        end
-      else // Ïóñòî:
-        if not isAnythingAt(x+s, y) {c = MARK_FREE} then
-          x := x + s
-        else // Îñòàëüíîå:
-          begin
-            die();
-            break;
-          end;
-    end;
-    {$ENDIF}
-  end;
-
-  if (dY <> 0) then
+  end
+  else if (dy <> 0) then
   begin
-    {$IF DEFINED(D2F_NEW_SPARK_THINKER)}
-    if (dY < 0) or not onGround then
+    // has some vertical velocity
+    if (dy < 0) then
     begin
-      pan := g_Map_traceToNearest(x, y, x, y+dY, (GridTagWall or GridTagDoor or GridTagStep or GridTagAcid1 or GridTagAcid2 or GridTagWater), @ex, @ey);
-      y := ey;
-      {
-      if awaken then
+      // flying up
+      if (ceilingY = Unknown) then findCeiling(); // need to do this anyway
+      y += dy;
+      if (y <= ceilingY) then
       begin
-        awaken := false;
-        e_LogWritefln('AWAKEN particle of type %s; justSticked=%s; onGround=%s; VelY=%s; AccelY=%s; Y=%s; ey=%s', [ParticleType, justSticked, onGround, VelY, AccelY, Y, ey]);
+        // oops, hit a ceiling
+        y := ceilingY;
+        velY := -velY;
+        accelY := abs(accelY);
       end;
-      }
-      // free to ride?
-      if (pan <> nil) then
+      // environment didn't changed
+    end
+    else
+    begin
+      // falling down
+      if (floorY = Unknown) then findFloor(); // need to do this anyway
+      y += dy;
+      if (y >= floorY) then
       begin
-        // nope
-        if ((pan.tag and (GridTagAcid1 or GridTagAcid2 or GridTagWater)) <> 0) then begin die(); exit; end;
-        if (dY < 0) then
-        begin
-          velY := -velY;
-          accelY := abs(accelY);
-        end
-        else
-        begin
-          velX := 0;
-          accelX := 0;
-          velY := 0;
-          accelY := 0.8;
-        end;
+        // hit something except a floor?
+        if (floorType <> TFloorType.Wall) then begin die(); exit; end; // yep: just die
+        // otherwise, go to sleep
+        y := floorY;
+        sleep();
+        // environment didn't changed
       end;
-      onGround := (velY >= 0) and g_Map_HasAnyPanelAtPoint(x, y+1, (PANEL_WALL or PANEL_CLOSEDOOR or PANEL_STEP));
-    end;
-    if (y < 0) or (y >= gMapInfo.Height) then begin die(); exit; end;
-    {$ELSE}
-    if (dY > 0) then s := 1 else s := -1;
-    dY := abs(dY);
-    for b := 1 to dY do
-    begin
-      if (y+s >= gMapInfo.Height) or (y+s <= 0) then begin die(); break; end;
-      //c := gCollideMap[Y+s, X];
-      if isBlockedAt(x, y+s) {ByteBool(c and MARK_BLOCKED)} then
-        begin // Ñòåíà/äâåðü - ïàäàåò âåðòèêàëüíî
-          if s < 0 then
-            begin
-              velY := -velY;
-              accelY := abs(accelY);
-            end
-          else // Èëè íå ïàäàåò
-            begin
-              velX := 0;
-              accelX := 0;
-              velY := 0;
-              accelY := 0.8;
-            end;
-
-          Break;
-        end
-      else // Ïóñòî:
-        if not isAnythingAt(x, y+s) {c = MARK_FREE} then
-          y := y + s
-        else // Îñàëüíîå:
-          begin
-            die();
-            break;
-          end;
     end;
-    {$ENDIF}
   end;
 
+_done:
+  if (x < g_Map_MinX) or (y < g_Map_MinY) or (x > g_Map_MaxX) or (y > g_Map_MaxY) then begin die(); end;
+
   if (velX <> 0.0) then velX += accelX;
 
   if (velY <> 0.0) then
@@ -1393,28 +1362,33 @@ begin
     velY += accelY;
   end;
 
-  time += 1;
+  //writeln('spark1: pos=(', x, ',', y, '); delta=(', velX:6:3, ',', velY:6:3, '); state=', state, '; ceilingY=', ceilingY, '; floorY=', floorY);
+
+  if waitTime > 0 then
+    waitTime -= 1
+  else
+    time += 1;
 end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
-procedure g_GFX_SparkVel (fX, fY: Integer; count: Word; VX, VY: Integer; devX, devY: Byte);
+procedure g_GFX_SparkVel (fX, fY: Integer; count: Word; vx, vy: Integer; devX, devY: Byte);
 var
   a: Integer;
-  devX1, devX2,
-  devY1, devY2: Byte;
+  devX1, devX2, devY1, devY2: Integer;
   l: Integer;
+  pan: TPanel;
 begin
-  exit;
-  if not gpart_dbg_enabled then Exit;
+  if not gpart_dbg_enabled then exit;
+
   l := Length(Particles);
-  if l = 0 then exit;
-  if count > l then count := l;
+  if (l = 0) then exit;
+  if (count > l) then count := l;
 
   devX1 := devX div 2;
-  devX2 := devX + 1;
+  devX2 := devX+1;
   devY1 := devY div 2;
-  devY2 := devY + 1;
+  devY2 := devY+1;
 
   for a := 1 to count do
   begin
@@ -1422,17 +1396,35 @@ begin
     begin
       x := fX-devX1+Random(devX2);
       y := fY-devY1+Random(devY2);
+      oldx := x;
+      oldy := y;
 
-      velX := VX + (Random-Random)*3;
-      velY := VY + (Random-Random)*3;
+      // check for level bounds
+      if (x < g_Map_MinX) or (y < g_Map_MinY) or (x > g_Map_MaxX) or (y > g_Map_MaxY) then continue;
 
-      if velY > -4 then
-        if velY-4 < -4 then
-          velY := -4
-        else
-          velY := velY-4;
+      // in what environment we are starting in?
+      pan := g_Map_PanelAtPoint(x, y, (GridTagSolid or GridTagLiquid));
+      if (pan <> nil) then
+      begin
+        // either in a wall, or in a liquid
+        //if ((pan.tag and GridTagSolid) <> 0) then continue; // don't spawn in walls
+        //env := TEnvType.ELiquid;
+        continue;
+      end
+      else
+      begin
+        env := TEnvType.EAir;
+      end;
+
+      velX := vx+(Random-Random)*3;
+      velY := vy+(Random-Random)*3;
+
+      if (velY > -4) then
+      begin
+        if (velY-4 < -4) then velY := -4 else velY := velY-4;
+      end;
 
-      accelX := -Sign(velX)*Random/100;
+      accelX := -sign(velX)*Random/100;
       accelY := 0.8;
 
       red := 255;
@@ -1440,63 +1432,76 @@ begin
       blue := 64;
       alpha := 255;
 
+      particleType := TPartType.Spark;
       state := TPartState.Normal;
       time := 0;
       liveTime := 30+Random(60);
-      particleType := TPartType.Spark;
-      justSticked := false;
-      onGround := (velY >= 0) and g_Map_HasAnyPanelAtPoint(x, y+1, (PANEL_WALL or PANEL_CLOSEDOOR or PANEL_STEP));
-      awaken := false;
+      waitTime := 0;
+      floorY := Unknown;
+      ceilingY := Unknown;
     end;
 
-    if CurrentParticle+2 > MaxParticles then
-      CurrentParticle := 0
-    else
-      CurrentParticle := CurrentParticle+1;
+    if (CurrentParticle >= MaxParticles-1) then CurrentParticle := 0 else CurrentParticle += 1;
   end;
 end;
 
 
-procedure g_GFX_Spark(fX, fY: Integer; count: Word; angle: SmallInt; devX, devY: Byte);
+procedure g_GFX_Spark (fX, fY: Integer; count: Word; angle: SmallInt; devX, devY: Byte);
 var
   a: Integer;
   b: Single;
-  devX1, devX2,
-  devY1, devY2: Byte;
-  BaseVelX, BaseVelY: Single;
+  devX1, devX2, devY1, devY2: Integer;
+  baseVelX, baseVelY: Single;
   l: Integer;
+  pan: TPanel;
 begin
-  exit;
-  if not gpart_dbg_enabled then Exit;
+  if not gpart_dbg_enabled then exit;
+
   l := Length(Particles);
-  if l = 0 then
-    Exit;
-  if count > l then
-    count := l;
+  if (l = 0) then exit;
+  if (count > l) then count := l;
 
-  angle := 360 - angle;
+  angle := 360-angle;
 
   devX1 := devX div 2;
-  devX2 := devX + 1;
+  devX2 := devX+1;
   devY1 := devY div 2;
-  devY2 := devY + 1;
+  devY2 := devY+1;
 
   b := DegToRad(angle);
-  BaseVelX := cos(b);
-  BaseVelY := 1.6*sin(b);
-  if abs(BaseVelX) < 0.01 then
-    BaseVelX := 0.0;
-  if abs(BaseVelY) < 0.01 then
-    BaseVelY := 0.0;
+  baseVelX := cos(b);
+  baseVelY := 1.6*sin(b);
+  if (abs(baseVelX) < 0.01) then baseVelX := 0.0;
+  if (abs(baseVelY) < 0.01) then baseVelY := 0.0;
+
   for a := 1 to count do
   begin
     with Particles[CurrentParticle] do
     begin
       x := fX-devX1+Random(devX2);
       y := fY-devY1+Random(devY2);
+      oldx := x;
+      oldy := y;
+
+      // check for level bounds
+      if (x < g_Map_MinX) or (y < g_Map_MinY) or (x > g_Map_MaxX) or (y > g_Map_MaxY) then continue;
+
+      // in what environment we are starting in?
+      pan := g_Map_PanelAtPoint(x, y, (GridTagSolid or GridTagLiquid));
+      if (pan <> nil) then
+      begin
+        // either in a wall, or in a liquid
+        //if ((pan.tag and GridTagSolid) <> 0) then continue; // don't spawn in walls
+        //env := TEnvType.ELiquid;
+        continue;
+      end
+      else
+      begin
+        env := TEnvType.EAir;
+      end;
 
-      velX := BaseVelX*Random;
-      velY := BaseVelY-Random;
+      velX := baseVelX*Random;
+      velY := baseVelY-Random;
       accelX := velX/3.0;
       accelY := velY/5.0;
 
@@ -1505,42 +1510,37 @@ begin
       blue := 64;
       alpha := 255;
 
+      particleType := TPartType.Spark;
       state := TPartState.Normal;
       time := 0;
       liveTime := 30+Random(60);
-      particleType := TPartType.Spark;
-      justSticked := false;
-      onGround := (velY >= 0) and g_Map_HasAnyPanelAtPoint(x, y+1, (PANEL_WALL or PANEL_CLOSEDOOR or PANEL_STEP));
-      awaken := false;
+      waitTime := 0;
+      floorY := Unknown;
+      ceilingY := Unknown;
     end;
 
-    if CurrentParticle+2 > MaxParticles then
-      CurrentParticle := 0
-    else
-      CurrentParticle := CurrentParticle+1;
+    if (CurrentParticle >= MaxParticles-1) then CurrentParticle := 0 else CurrentParticle += 1;
   end;
 end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
-procedure g_GFX_SetMax(count: Integer);
+procedure g_GFX_SetMax (count: Integer);
 var
   a: Integer;
 begin
   if count > 50000 then count := 50000;
   if (count < 1) then count := 1;
-
   SetLength(Particles, count);
   for a := 0 to High(Particles) do Particles[a].die();
   MaxParticles := count;
-  //if CurrentParticle >= Count then
-    CurrentParticle := 0;
+  CurrentParticle := 0;
 end;
 
 
-function g_GFX_GetMax(): Integer;
+function g_GFX_GetMax (): Integer;
 begin
-  Result := MaxParticles;
+  result := MaxParticles;
 end;
 
 
@@ -1573,9 +1573,9 @@ procedure g_GFX_OnceAnim (x, y: Integer; Anim: TAnimation; AnimType: Byte = 0);
 var
   find_id: DWORD;
 begin
-  if not gpart_dbg_enabled then Exit;
-  if Anim = nil then
-    Exit;
+  if not gpart_dbg_enabled then exit;
+
+  if (Anim = nil) then exit;
 
   find_id := FindOnceAnim();
 
@@ -1589,58 +1589,19 @@ end;
 
 
 // ////////////////////////////////////////////////////////////////////////// //
-// st: set mark
-// t: mark type
-// currently unused
-procedure g_Mark(x, y, Width, Height: Integer; t: Byte; st: Boolean=true);
-var
-  cx, ex, ey: Integer;
-  ts: Integer;
-begin
-  if (Width < 1) or (Height < 1) then exit;
-  // make some border, so we'll hit particles lying around the panel
-  x -= 1; Width += 2;
-  y -= 1; Height += 2;
-  ex := x+Width;
-  ey := y+Height;
-  ts := mapGrid.tileSize;
-  while (y < ey) do
-  begin
-    cx := x;
-    while (cx < ex) do
-    begin
-      awmSet(cx, y);
-      Inc(cx, ts);
-    end;
-    Inc(y, ts);
-  end;
-end;
-
-
-// ////////////////////////////////////////////////////////////////////////// //
-{$IF DEFINED(HAS_COLLIDE_BITMAP)}
-procedure CreateCollideMap();
-var
-  a: Integer;
+procedure g_GFX_Init ();
 begin
   //g_Game_SetLoadingText(_lc[I_LOAD_COLLIDE_MAP]+' 1/6', 0, False);
   //SetLength(gCollideMap, gMapInfo.Height+1);
   //for a := 0 to High(gCollideMap) do SetLength(gCollideMap[a], gMapInfo.Width+1);
-end;
-{$ENDIF}
-
-
-procedure g_GFX_Init();
-begin
-  //CreateCollideMap();
   awmSetup();
 {$IFDEF HEADLESS}
-  gpart_dbg_enabled := False;
+  gpart_dbg_enabled := false;
 {$ENDIF}
 end;
 
 
-procedure g_GFX_Free();
+procedure g_GFX_Free ();
 var
   a: Integer;
 begin
@@ -1686,8 +1647,6 @@ begin
         begin
           if (time = liveTime) then begin die(); continue; end;
           if (x+1 >= w) or (y+1 >= h) or (x <= 0) or (y <= 0) then begin die(); end;
-          //if not alive then Continue;
-          //e_WriteLog(Format('particle #%d: %d', [State, ParticleType]), MSG_NOTIFY);
           think();
         end; // with
       end; // if
@@ -1702,6 +1661,9 @@ begin
     for a := 0 to High(OnceAnims) do
       if OnceAnims[a].Animation <> nil then
       begin
+        OnceAnims[a].oldx := OnceAnims[a].x;
+        OnceAnims[a].oldy := OnceAnims[a].y;
+
         case OnceAnims[a].AnimType of
           ONCEANIM_SMOKE:
             begin
@@ -1723,42 +1685,4 @@ begin
   end;
 end;
 
-
-procedure g_GFX_Draw ();
-var
-  a, len: Integer;
-begin
-  if Particles <> nil then
-  begin
-    glDisable(GL_TEXTURE_2D);
-    glPointSize(2);
-
-    glEnable(GL_BLEND);
-    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
-
-    glBegin(GL_POINTS);
-
-    len := High(Particles);
-
-    for a := 0 to len do
-      with Particles[a] do
-        if alive and (x >= sX) and (y >= sY) and (x <= sX+sWidth) and (sY <= sY+sHeight) then
-        begin
-          glColor4ub(red, green, blue, alpha);
-          glVertex2i(x + offsetX, y + offsetY);
-        end;
-
-    glEnd();
-
-    glDisable(GL_BLEND);
-  end;
-
-  if OnceAnims <> nil then
-    for a := 0 to High(OnceAnims) do
-      if OnceAnims[a].Animation <> nil then
-        with OnceAnims[a] do
-          Animation.Draw(x, y, M_NONE);
-end;
-
-
 end.