1 /*

     2 * Copyright (c) 2008 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of the License "Eclipse Public License v1.0"

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:   Implementation of scrolling decelerator

    15 *

    16 */

    17 

    18 

    19 // INCLUDE FILES

    20 #include <../bidi.h>

    21 #include "WebScrollingDeceleratorGH.h"

    22 #include "WebView.h"

    23 #include "WebFrame.h"

    24 #include "WebFrameView.h"

    25 #include "WebPageScrollHandler.h"

    26 #include "PlatformScrollbar.h"

    27 #include "WebScrollbarDrawer.h"

    28 

    29 #include "WebKitLogger.h"

    30 

    31 using namespace RT_GestureHelper;

    32 // constants

    33 const int KRecordSize = 4;

    34 

    35 // The following deceleration curve is generated by a script

    36 // It lists the timeout dt values in microseconds.

    37 const int KDecelCurveSize = 10;

    38 

    39 const int KScrollIntervalTimeout = 60000; // scroll timer interval in microseconds

    40 

    41 const float KDecceleration = -700.0;

    42 

    43 int decelTimerCB(TAny* ptr);

    44 

    45 

    46 // ============================ MEMBER FUNCTIONS ===============================

    47 

    48 // -----------------------------------------------------------------------------

    49 // WebScrollingDeceleratorGH::NewL

    50 // The two-phase Symbian constructor

    51 // -----------------------------------------------------------------------------

    52 //

    53 

    54 WebScrollingDeceleratorGH* WebScrollingDeceleratorGH::NewL(WebView& webView)

    55 {

    56     WebScrollingDeceleratorGH* self = new (ELeave) WebScrollingDeceleratorGH(webView);

    57 

    58     CleanupStack::PushL(self);

    59     self->ConstructL();

    60     CleanupStack::Pop(); //self

    61     return self;

    62 }

    63 

    64 // -----------------------------------------------------------------------------

    65 // WebScrollingDeceleratorGH::WebScrollingDeceleratorGH

    66 // C++ default constructor can NOT contain any code, that

    67 // might leave.

    68 // -----------------------------------------------------------------------------

    69 //

    70 WebScrollingDeceleratorGH::WebScrollingDeceleratorGH(WebView& webView)

    71 :  m_webView( webView )

    72 {

    73 }

    74 

    75 // -----------------------------------------------------------------------------

    76 // WebScrollingDeceleratorGH::ConstructL

    77 // -----------------------------------------------------------------------------

    78 void WebScrollingDeceleratorGH::ConstructL()

    79 {

    80     m_decelTimer = CPeriodic::NewL(CActive::EPriorityStandard);

    81 }

    82 

    83 // -----------------------------------------------------------------------------

    84 // Destructor

    85 // -----------------------------------------------------------------------------

    86 WebScrollingDeceleratorGH::~WebScrollingDeceleratorGH()

    87 {

    88     delete m_decelTimer;

    89 }

    90 

    91 

    92 int WebScrollingDeceleratorGH::getDecceleration()

    93 {

    94    return  KDecceleration;  

    95 }

    96 

    97 

    98 int decelTimerCB(TAny* ptr)

    99 {

   100     (static_cast<WebScrollingDeceleratorGH*>(ptr))->scroll();

   101     return false;

   102 }

   103 

   104 

   105 void WebScrollingDeceleratorGH::cancelDecel() 

   106 { 

   107     m_decelelatorSwitch = false;

   108     if (m_decelTimer->IsActive()) {

   109         m_decelTimer->Cancel();

   110     }

   111 }

   112 

   113 void WebScrollingDeceleratorGH::startDecel(TRealPoint& speed, WebScrollbarDrawer* scrollbarDrawer)

   114 {

   115     m_decelelatorSwitch = true;

   116     m_scrollbarDrawer = scrollbarDrawer;

   117     m_initSpeed.iX = (-1) * speed.iX;

   118     m_initSpeed.iY = (-1) * speed.iY;

   119     

   120     m_numscrollsteps = 0;

   121     if (m_decelTimer->IsActive()) {

   122         m_decelTimer->Cancel();

   123     }

   124     

   125     WebFrameView* scrollingView = m_webView.pageScrollHandler()->currentScrollingFrameView();

   126     if (scrollingView) {

   127         m_startPos = scrollingView->contentPos();

   128         m_lastPos = m_startPos;

   129         m_decelTimer->Start(0, KScrollIntervalTimeout, 

   130                             TCallBack(&decelTimerCB, this));

   131     }

   132 }

   133 

   134 void WebScrollingDeceleratorGH::scroll()

   135 {

   136     if (!m_decelelatorSwitch) return;

   137     // X = Vst*t - 0.5*a*(t * t)    

   138     TPoint dist;

   139     TReal32 intervalInSec = static_cast<TReal32>(KScrollIntervalTimeout) / 1000000;

   140     TReal32 t = (m_numscrollsteps++) * intervalInSec;

   141     TReal32 dx = 0.0;

   142     TReal32 dy = 0.0;

   143     TReal32 vx = 0.0;

   144     TReal32 vy = 0.0;

   145     TReal32 accelX = 0.0;

   146     TReal32 accelY = 0.0;

   147     

   148     if (m_initSpeed.iX) {

   149         accelX = (m_initSpeed.iX > 0) ?  KDecceleration : (-1) * KDecceleration;

   150         vx = m_initSpeed.iX + accelX * t;

   151         dx = m_initSpeed.iX * t + 0.5 * accelX * (t * t);

   152     }

   153         

   154     if (m_initSpeed.iY) {

   155         accelY = (m_initSpeed.iY > 0) ?  KDecceleration : (-1) * KDecceleration;

   156         vy = m_initSpeed.iY + accelY * t;

   157         dy = m_initSpeed.iY * t + 0.5 * accelY * (t * t);

   158     }

   159     

   160     dist.SetXY(static_cast<TInt>(dx), static_cast<TInt>(dy));

   161     

   162     WebFrameView* scrollingView = m_webView.pageScrollHandler()->currentScrollingFrameView();

   163     TPoint cpos = scrollingView->contentPos();

   164     dist = scrollingView->toDocCoords(dist);

   165     TPoint pos = m_startPos + dist;

   166     

   167     if ((vx * m_initSpeed.iX < 0) || (vy * m_initSpeed.iY < 0) || (vx + vy == 0) ||

   168         (m_numscrollsteps > 1 && !scrollingView->needScroll(pos))) {

   169         if (m_scrollbarDrawer) {

   170             m_scrollbarDrawer->fadeScrollbar();

   171         }

   172         m_decelTimer->Cancel();

   173         m_webView.setViewIsScrolling(false);

   174         m_webView.toggleRepaintTimer(true);

   175     }

   176     else {

   177         scrollingView->scrollTo(pos);

   178         if (m_scrollbarDrawer) {

   179             TPoint scrollDelta = pos - m_lastPos;

   180             scrollDelta.iX *= 100;

   181             scrollDelta.iY *= 100;

   182             m_webView.pageScrollHandler()->updateScrollbars(pos, scrollDelta);   

   183         }

   184         m_lastPos = pos;

   185     }

   186     

   187 }

   188 

   189 

   190 //  End of File