(*

 * Hedgewars, a free turn based strategy game

 * Copyright (c) 2012 Richard Deurwaarder <xeli@xelification.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 uTouch;

interface

procedure initModule;

procedure ProcessTouch;

procedure onTouchDown(x,y: Longword; pointerId: TSDL_FingerId);

procedure onTouchMotion(x,y: Longword; dx,dy: LongInt; pointerId: TSDL_FingerId);

procedure onTouchUp(x,y: Longword; pointerId: TSDL_FingerId);

function convertToCursorX(x: LongInt): LongInt;

function convertToCursorY(y: LongInt): LongInt;

function convertToCursorDeltaX(x: LongInt): LongInt;

function convertToCursorDeltaY(y: LongInt): LongInt;

function addFinger(x,y: Longword; id: TSDL_FingerId): PTouch_Data;

function updateFinger(x,y,dx,dy: Longword; id: TSDL_FingerId): PTouch_Data;

procedure deleteFinger(id: TSDL_FingerId);

procedure onTouchClick(finger: TTouch_Data);

procedure onTouchDoubleClick(finger: TTouch_Data);

function findFinger(id: TSDL_FingerId): PTouch_Data;

procedure aim(finger: TTouch_Data);

function isOnCrosshair(finger: TTouch_Data): boolean;

function isOnCurrentHog(finger: TTouch_Data): boolean;

procedure convertToWorldCoord(var x,y: LongInt; finger: TTouch_Data);

procedure convertToFingerCoord(var x,y: LongInt; oldX, oldY: LongInt);

function fingerHasMoved(finger: TTouch_Data): boolean;

function calculateDelta(finger1, finger2: TTouch_Data): LongInt;

function getSecondFinger(finger: TTouch_Data): PTouch_Data;

function isOnRect(rect: TSDL_Rect; finger: TTouch_Data): boolean;

function isOnRect(x,y,w,h: LongInt; finger: TTouch_Data): boolean;

procedure printFinger(finger: TTouch_Data);

implementation

const

    nilFingerId = High(TSDL_FingerId);

var

    pointerCount : Longword;

    fingers: array of TTouch_Data;

    moveCursor : boolean;

    invertCursor : boolean;

    xTouchClick,yTouchClick : LongInt;

    timeSinceClick : Longword;

    //Pinch to zoom 

    pinchSize : LongInt;

    baseZoomValue: GLFloat;

    //aiming

    aimingCrosshair: boolean;

    aimingUp, aimingDown: boolean; 

    targetAngle: LongInt;

    buttonsDown: Longword;

procedure onTouchDown(x,y: Longword; pointerId: TSDL_FingerId);

var 

    finger: PTouch_Data;

begin

{$IFDEF USE_TOUCH_INTERFACE}

finger := addFinger(x,y,pointerId);

inc(buttonsDown);//inc buttonsDown, if we don't see a button down we'll dec it

if isOnCrosshair(finger^) then

begin

    aimingCrosshair:= true;

    aim(finger^);

    moveCursor:= false;

    exit;

end;

if isOnRect(fireButton.active, finger^) then

    begin

    spaceKey:= true;

    moveCursor:= false;

    finger^.pressedWidget:= @fireButton;

    exit;

    end;

if isOnRect(arrowLeft.active, finger^) then

    begin

    leftKey:= true;

    moveCursor:= false;

    finger^.pressedWidget:= @arrowLeft;

    exit;

    end;

if isOnRect(arrowRight.active, finger^) then

    begin

    rightKey:= true;

    moveCursor:= false;

    finger^.pressedWidget:= @arrowRight;

    exit;

    end;

if isOnRect(arrowUp.active, finger^) then

     begin

     upKey:= true;

     moveCursor:= false;

     finger^.pressedWidget:= @arrowUp;

     exit;

     end;

if isOnRect(arrowDown.active, finger^) then

     begin

     downKey:= true;

     moveCursor:= false;

     finger^.pressedWidget:= @arrowDown;

     exit;

     end;

if isOnRect(pauseButton.active, finger^) then

     begin

     isPaused:= not isPaused;

     moveCursor:= false;

     finger^.pressedWidget:= @pauseButton;

     exit;

     end;

dec(buttonsDown);//no buttonsDown, undo the inc() above

if buttonsDown = 0 then

    begin

    moveCursor:= true;

    if pointerCount = 2 then

        begin

        moveCursor:= false;

        pinchSize := calculateDelta(finger^, getSecondFinger(finger^)^);

        baseZoomValue := ZoomValue

    end;

end;

{$ENDIF}

end;

procedure onTouchMotion(x,y: Longword;dx,dy: LongInt; pointerId: TSDL_FingerId);

var

    finger, secondFinger: PTouch_Data;

    currentPinchDelta, zoom : single;

begin

finger:= updateFinger(x,y,dx,dy,pointerId);

if moveCursor then

    begin

        if invertCursor then

        begin

            CursorPoint.X := CursorPoint.X - finger^.dx;

            CursorPoint.Y := CursorPoint.Y + finger^.dy;

        end

    else

        begin

            CursorPoint.X := CursorPoint.X + finger^.dx;

            CursorPoint.Y := CursorPoint.Y - finger^.dy;

        end;

        exit //todo change into switch rather than ugly ifs

    end;

if aimingCrosshair then 

    begin

        aim(finger^);

        exit

    end;

if (buttonsDown = 0) and (pointerCount = 2) then

    begin

       secondFinger := getSecondFinger(finger^);

       currentPinchDelta := calculateDelta(finger^, secondFinger^) - pinchSize;

       zoom := currentPinchDelta/cScreenWidth;

       ZoomValue := baseZoomValue - (zoom * cMinMaxZoomLevelDelta);

       if ZoomValue < cMaxZoomLevel then

           ZoomValue := cMaxZoomLevel;

       if ZoomValue > cMinZoomLevel then

           ZoomValue := cMinZoomLevel;

    end;

end;

procedure onTouchUp(x,y: Longword; pointerId: TSDL_FingerId);

var

    finger: PTouch_Data;

    widget: POnScreenWidget;

begin

{$IFDEF USE_TOUCH_INTERFACE}

x := x;

y := y;

finger:= updateFinger(x,y,0,0,pointerId);

//Check for onTouchClick event

if aimingCrosshair then

    begin

    aimingCrosshair:= false;

    upKey:= false;

    downKey:= false;

    dec(buttonsDown);

    end;

widget:= finger^.pressedWidget;

if (buttonsDown > 0) and (widget <> nil) then

    begin

    dec(buttonsDown);

    if widget = @arrowLeft then

        leftKey:= false;

    if widget = @arrowRight then

        rightKey:= false;

    if widget = @arrowUp then

        upKey:= false;

    if widget = @arrowDown then

        downKey:= false;

    if widget = @fireButton then

        spaceKey:= false;

    end;

deleteFinger(pointerId);

{$ENDIF}

end;

procedure onTouchDoubleClick(finger: TTouch_Data);

begin

finger := finger;//avoid compiler hint

end;

procedure onTouchClick(finger: TTouch_Data);

begin

xTouchClick:= finger.x;

yTouchClick:= finger.y;

timeSinceClick:= RealTicks;

if bShowAmmoMenu then

    begin 

    if isOnRect(AmmoRect, finger) then

        begin

        CursorPoint.X:= finger.x;

        CursorPoint.Y:= finger.y;

        doPut(CursorPoint.X, CursorPoint.Y, false); 

        end

    else

        bShowAmmoMenu:= false;

    exit;

    end;

if isOnCurrentHog(finger) then

    begin

    bShowAmmoMenu := true;

    exit;

    end;

end;

function addFinger(x,y: Longword; id: TSDL_FingerId): PTouch_Data;

var 

    xCursor, yCursor, index : LongInt;

begin

    //Check array sizes

    if length(fingers) < Integer(pointerCount) then 

    begin

        setLength(fingers, length(fingers)*2);

        for index := length(fingers) div 2 to length(fingers) do

            fingers[index].id := nilFingerId;

    end;

    xCursor := convertToCursorX(x);

    yCursor := convertToCursorY(y);

    //on removing fingers, all fingers are moved to the left

    //with dynamic arrays being zero based, the new position of the finger is the old pointerCount

    fingers[pointerCount].id := id;

    fingers[pointerCount].historicalX := xCursor;

    fingers[pointerCount].historicalY := yCursor;

    fingers[pointerCount].x := xCursor;

    fingers[pointerCount].y := yCursor;

    fingers[pointerCount].dx := 0;

    fingers[pointerCount].dy := 0;

    fingers[pointerCount].timeSinceDown:= RealTicks;

    fingers[pointerCount].pressedWidget:= nil;

    addFinger:= @fingers[pointerCount];

    inc(pointerCount);

end;

function updateFinger(x,y,dx,dy: Longword; id: TSDL_FingerId): PTouch_Data;

begin

   updateFinger:= findFinger(id);

   updateFinger^.x:= convertToCursorX(x);

   updateFinger^.y:= convertToCursorY(y);

   updateFinger^.dx:= convertToCursorDeltaX(dx);

   updateFinger^.dy:= convertToCursorDeltaY(dy);

end;

procedure deleteFinger(id: TSDL_FingerId);

var

    index : Longword;

begin

    dec(pointerCount);

    for index := 0 to pointerCount do

    begin

        if fingers[index].id = id then

        begin

            //put the last finger into the spot of the finger to be removed, 

            //so that all fingers are packed to the far left

            if  pointerCount <> index then

                begin

                fingers[index].id := fingers[pointerCount].id;    

                fingers[index].x := fingers[pointerCount].x;    

                fingers[index].y := fingers[pointerCount].y;    

                fingers[index].historicalX := fingers[pointerCount].historicalX;    

                fingers[index].historicalY := fingers[pointerCount].historicalY;    

                fingers[index].timeSinceDown := fingers[pointerCount].timeSinceDown;

                fingers[pointerCount].id := nilFingerId;

            end

        else fingers[index].id := nilFingerId;

            break;

        end;

    end;

end;

procedure ProcessTouch;

var

    deltaAngle: LongInt;

begin

invertCursor := not(bShowAmmoMenu);

if aimingCrosshair then

    if CurrentHedgehog^.Gear <> nil then

        begin

        deltaAngle:= CurrentHedgehog^.Gear^.Angle - targetAngle;

        if (deltaAngle > -5) and (deltaAngle < 5) then 

            begin

                upKey:= false;

                aimingUp:= false;

                downKey:= false;

                aimingDown:= false;

            end

        else

            begin

            if (deltaAngle < 0) then

                begin

                if aimingUp then

                    begin

                    upKey:= false;

                    aimingUp:= false;

                    end;

                downKey:= true;

                aimingDown:= true;

                end

            else

                begin

                if aimingDown then

                    begin

                    downKey:= false;

                    aimingDown:= false;

                    end;

                upKey:= true;

                aimingUp:= true;

                end; 

            end;

        end

    else  

        begin

        if aimingUp then

            begin

            upKey:= false;

            aimingUp:= false;

            end;

        if aimingDown then

            begin

            upKey:= false;

            aimingDown:= false;

            end;

        end;

end;

function findFinger(id: TSDL_FingerId): PTouch_Data;

var

    index: LongWord;

begin

    for index := 0 to High(fingers) do

        if fingers[index].id = id then 

            begin

            findFinger := @fingers[index];

            break;

            end;

end;

procedure aim(finger: TTouch_Data);

var 

    hogX, hogY, touchX, touchY, deltaX, deltaY: LongInt;

begin

    if CurrentHedgehog^.Gear <> nil then

        begin

        touchX := 0;//avoid compiler hint

        touchY := 0;

        hogX := hwRound(CurrentHedgehog^.Gear^.X);

        hogY := hwRound(CurrentHedgehog^.Gear^.Y);

        convertToWorldCoord(touchX, touchY, finger);

        deltaX := abs(TouchX-HogX);

        deltaY := TouchY-HogY;

        targetAngle:= (Round(DeltaY / sqrt(sqr(deltaX) + sqr(deltaY)) * 2048) + 2048) div 2;

        end; //if CurrentHedgehog^.Gear <> nil

end;

// These 4 convertToCursor functions convert xy coords from the SDL coordinate system to our CursorPoint coor system:

// - the SDL coordinate system goes from 0 to 32768 on the x axis and 0 to 32768 on the y axis, (0,0) being top left;

// - the CursorPoint coordinate system goes from -cScreenWidth/2 to cScreenWidth/2 on the x axis

//   and 0 to cScreenHeight on the x axis, (-cScreenWidth, cScreenHeight) being top left.

function convertToCursorX(x: LongInt): LongInt;

begin

    convertToCursorX := round((x/32768)*cScreenWidth) - (cScreenWidth shr 1);

end;

function convertToCursorY(y: LongInt): LongInt;

begin

    convertToCursorY := cScreenHeight - round((y/32768)*cScreenHeight)

end;

function convertToCursorDeltaX(x: LongInt): LongInt;

begin

    convertToCursorDeltaX := round(x/32768*cScreenWidth)

end;