(*

 * Hedgewars, a free turn based strategy game

 * Copyright (c) 2008 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

 *)

unit uVisualGears;

interface

uses SDLh, uConsts, uFloat, GL;

{$INCLUDE options.inc}

const AllInactive: boolean = false;

type PVisualGear = ^TVisualGear;

     TVGearStepProcedure = procedure (Gear: PVisualGear; Steps: Longword);

     TVisualGear = record

             NextGear, PrevGear: PVisualGear;

             Frame,

             FrameTicks: Longword;

             X : hwFloat;

             Y : hwFloat;

             dX: hwFloat;

             dY: hwFloat;

             mdY: QWord;

             Angle, dAngle: real;

             Kind: TVisualGearType;

             doStep: TVGearStepProcedure;

             end;

function  AddVisualGear(X, Y: LongInt; Kind: TVisualGearType): PVisualGear;

procedure ProcessVisualGears(Steps: Longword);

procedure DrawVisualGears(Layer: LongWord);

procedure DeleteVisualGear(Gear: PVisualGear);

procedure AddClouds;

var VisualGearsList: PVisualGear = nil;

    vobFrameTicks, vobFramesCount: Longword;

    vobVelocity, vobFallSpeed: LongInt;

implementation

uses uWorld, uMisc, uStore;

const cExplFrameTicks = 110;

// ==================================================================

procedure doStepFlake(Gear: PVisualGear; Steps: Longword);

begin

with Gear^ do

  begin

  inc(FrameTicks, Steps);

  if FrameTicks > vobFrameTicks then

    begin

    dec(FrameTicks, vobFrameTicks);

    inc(Frame);

    if Frame = vobFramesCount then Frame:= 0

    end

  end;

Gear^.X:= Gear^.X + (cWindSpeed * 200 + Gear^.dX) * Steps;

Gear^.Y:= Gear^.Y + (Gear^.dY + cGravity * vobFallSpeed) * Steps;

Gear^.Angle:= Gear^.Angle + Gear^.dAngle * Steps;

if hwRound(Gear^.X) < -cScreenWidth - 64 then Gear^.X:= int2hwFloat(cScreenWidth + 2048) else

if hwRound(Gear^.X) > cScreenWidth + 2048 then Gear^.X:= int2hwFloat(-cScreenWidth - 64);

if hwRound(Gear^.Y) > 1100 then Gear^.Y:= Gear^.Y - int2hwFloat(1228)

end;

procedure doStepCloud(Gear: PVisualGear; Steps: Longword);

var i: Longword;

begin

Gear^.X:= Gear^.X + (cWindSpeed * 200 + Gear^.dX) * Steps;

for i:= 0 to Steps - 1 do

	begin

	if hwRound(Gear^.Y) > -160 then

		Gear^.dY:= Gear^.dY - _1div50000

	else

		Gear^.dY:= Gear^.dY + _1div50000;

	Gear^.Y:= Gear^.Y + Gear^.dY

	end;

if hwRound(Gear^.X) < -cScreenWidth - 256 then Gear^.X:= int2hwFloat(cScreenWidth + 2048) else

if hwRound(Gear^.X) > cScreenWidth + 2048 then Gear^.X:= int2hwFloat(-cScreenWidth - 256)

end;

procedure doStepExpl(Gear: PVisualGear; Steps: Longword);

begin

Gear^.X:= Gear^.X + Gear^.dX * Steps;

Gear^.Y:= Gear^.Y + Gear^.dY * Steps;

//Gear^.dY:= Gear^.dY + cGravity;

if Gear^.FrameTicks <= Steps then

	if Gear^.Frame = 0 then DeleteVisualGear(Gear)

	else

		begin

		dec(Gear^.Frame);

		Gear^.FrameTicks:= cExplFrameTicks

		end

	else dec(Gear^.FrameTicks, Steps)

end;

procedure doStepFire(Gear: PVisualGear; Steps: Longword);

begin

Gear^.X:= Gear^.X + Gear^.dX * Steps;

Gear^.Y:= Gear^.Y + Gear^.dY * Steps;// + cGravity * (Steps * Steps);

Gear^.dY:= Gear^.dY + cGravity * Steps;

if Gear^.FrameTicks <= Steps then

	DeleteVisualGear(Gear)

else

	dec(Gear^.FrameTicks, Steps)

end;

// ==================================================================

const doStepHandlers: array[TVisualGearType] of TVGearStepProcedure =

                        (

                          @doStepFlake,

                          @doStepCloud,

                          @doStepExpl,

                          @doStepExpl,

                          @doStepFire

                        );

function  AddVisualGear(X, Y: LongInt; Kind: TVisualGearType): PVisualGear;

var Result: PVisualGear;

	t: Longword;

	sp: hwFloat;

begin

New(Result);

FillChar(Result^, sizeof(TVisualGear), 0);

Result^.X:= int2hwFloat(X);

Result^.Y:= int2hwFloat(Y);

Result^.Kind := Kind;

Result^.doStep:= doStepHandlers[Kind];

case Kind of

   vgtFlake: with Result^ do

               begin

               FrameTicks:= random(vobFrameTicks);

               Frame:= random(vobFramesCount);

               Angle:= random * 360;

               dx.isNegative:= random(2) = 0;

               dx.QWordValue:= random(100000000);

               dy.isNegative:= false;

               dy.QWordValue:= random(70000000);

               dAngle:= (random(2) * 2 - 1) * (1 + random) * vobVelocity / 1000

               end;

   vgtCloud: with Result^ do

               begin

               Frame:= random(4);

               dx.isNegative:= random(2) = 0;

               dx.QWordValue:= random(214748364);

               dy.isNegative:= random(2) = 0;

               dy.QWordValue:= 21474836 + random(64424509);

               mdY:= dy.QWordValue

               end;

  vgtExplPart,

 vgtExplPart2: with Result^ do

               begin

               t:= random(1024);

               sp:= _0_001 * (random(95) + 70);

               dx:= AngleSin(t) * sp;

               dx.isNegative:= random(2) = 0;

               dy:= AngleCos(t) * sp;

               dy.isNegative:= random(2) = 0;

               Frame:= 7 - random(3);

               FrameTicks:= cExplFrameTicks

               end;

      vgtFire: with Result^ do

               begin

               t:= random(1024);

               sp:= _0_001 * (random(85) + 95);

               dx:= AngleSin(t) * sp;

               dx.isNegative:= random(2) = 0;

               dy:= AngleCos(t) * sp;

               dy.isNegative:= random(2) = 0;

               FrameTicks:= 650 + random(250);

               Frame:= random(8)

               end;

     end;

if VisualGearsList <> nil then

   begin

   VisualGearsList^.PrevGear:= Result;

   Result^.NextGear:= VisualGearsList

   end;

VisualGearsList:= Result;

AddVisualGear:= Result

end;

procedure DeleteVisualGear(Gear: PVisualGear);

begin

if Gear^.NextGear <> nil then Gear^.NextGear^.PrevGear:= Gear^.PrevGear;

if Gear^.PrevGear <> nil then Gear^.PrevGear^.NextGear:= Gear^.NextGear

   else VisualGearsList:= Gear^.NextGear;

Dispose(Gear)

end;

procedure ProcessVisualGears(Steps: Longword);

var Gear, t: PVisualGear;

begin

if Steps = 0 then exit;

t:= VisualGearsList;

while t <> nil do

      begin

      Gear:= t;

      t:= Gear^.NextGear;

      Gear^.doStep(Gear, Steps)

      end

end;

procedure DrawVisualGears(Layer: LongWord);

var Gear: PVisualGear;

begin

Gear:= VisualGearsList;

case Layer of

	0: while Gear <> nil do

		begin

		case Gear^.Kind of

			vgtFlake: if vobVelocity = 0 then

						DrawSprite(sprFlake, hwRound(Gear^.X) + WorldDx, hwRound(Gear^.Y) + WorldDy, Gear^.Frame)

					else

						DrawRotatedF(sprFlake, hwRound(Gear^.X) + WorldDx, hwRound(Gear^.Y) + WorldDy, Gear^.Frame, 1, Gear^.Angle);

			vgtCloud: DrawSprite(sprCloud, hwRound(Gear^.X) + WorldDx, hwRound(Gear^.Y) + WorldDy, Gear^.Frame);

			end;

		Gear:= Gear^.NextGear

		end;

	1: while Gear <> nil do

		begin

		case Gear^.Kind of

			vgtExplPart: DrawSprite(sprExplPart, hwRound(Gear^.X) + WorldDx, hwRound(Gear^.Y) + WorldDy, 7 - Gear^.Frame);

			vgtExplPart2: DrawSprite(sprExplPart2, hwRound(Gear^.X) + WorldDx, hwRound(Gear^.Y) + WorldDy, 7 - Gear^.Frame);

			vgtFire: DrawSprite(sprFlame, hwRound(Gear^.X) + WorldDx, hwRound(Gear^.Y) + WorldDy, (RealTicks div 64 + Gear^.Frame) mod 8);

			end;

		Gear:= Gear^.NextGear

		end

	end

end;

procedure AddClouds;

var i: LongInt;

begin

for i:= 0 to cCloudsNumber do

    AddVisualGear( - cScreenWidth + i * ((cScreenWidth * 2 + 2304) div cCloudsNumber), -160, vgtCloud)

end;

initialization

finalization

end.