slideshow/source/engine/activities/activitybase.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
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  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <sal/config.h>
  21
  22 #include <algorithm>
  23
  24 #include <comphelper/diagnose_ex.hxx>
  25
  26 #include "activitybase.hxx"
  27
  28
  29 namespace slideshow::internal
  30 {
  31         // TODO(P1): Elide some virtual function calls, by templifying this
  32         // static hierarchy
  33
  34         ActivityBase::ActivityBase( const ActivityParameters& rParms ) :
  35             mpEndEvent( rParms.mrEndEvent ),
  36             mrEventQueue( rParms.mrEventQueue ),
  37             mpShape(),
  38             mpAttributeLayer(),
  39             maRepeats( rParms.mrRepeats ),
  40             mnAccelerationFraction( rParms.mnAccelerationFraction ),
  41             mnDecelerationFraction( rParms.mnDecelerationFraction ),
  42             mbAutoReverse( rParms.mbAutoReverse ),
  43             mbFirstPerformCall( true ),
  44             mbIsActive( true ) {}
  45
  46         void ActivityBase::dispose()
  47         {
  48             // deactivate
  49             mbIsActive = false;
  50
  51             // dispose event
  52             if( mpEndEvent )
  53                 mpEndEvent->dispose();
  54
  55             // release references
  56             mpEndEvent.reset();
  57             mpShape.reset();
  58             mpAttributeLayer.reset();
  59         }
  60
  61         double ActivityBase::calcTimeLag() const
  62         {
  63             // TODO(Q1): implement different init process!
  64             if (isActive() && mbFirstPerformCall)
  65             {
  66                 mbFirstPerformCall = false;
  67
  68                 // notify derived classes that we're
  69                 // starting now
  70                 const_cast<ActivityBase *>(this)->startAnimation();
  71             }
  72             return 0.0;
  73         }
  74
  75         bool ActivityBase::perform()
  76         {
  77             // still active?
  78             if( !isActive() )
  79                 return false; // no, early exit.
  80
  81             OSL_ASSERT( ! mbFirstPerformCall );
  82
  83             return true;
  84         }
  85
  86         bool ActivityBase::isActive() const
  87         {
  88             return mbIsActive;
  89         }
  90
  91         void ActivityBase::setTargets( const AnimatableShapeSharedPtr&      rShape,
  92                                        const ShapeAttributeLayerSharedPtr&  rAttrLayer )
  93         {
  94             ENSURE_OR_THROW( rShape,
  95                               "ActivityBase::setTargets(): Invalid shape" );
  96             ENSURE_OR_THROW( rAttrLayer,
  97                               "ActivityBase::setTargets(): Invalid attribute layer" );
  98
  99             mpShape = rShape;
 100             mpAttributeLayer = rAttrLayer;
 101         }
 102
 103         void ActivityBase::endActivity()
 104         {
 105             // this is a regular activity end
 106             mbIsActive = false;
 107
 108             // Activity is ending, queue event, then
 109             if( mpEndEvent )
 110                 mrEventQueue.addEvent( mpEndEvent );
 111
 112             // release references
 113             mpEndEvent.reset();
 114         }
 115
 116         void ActivityBase::dequeued()
 117         {
 118             // xxx todo:
 119 //             // ignored here, if we're still active. Discrete
 120 //             // activities are dequeued after every perform() call,
 121 //             // thus, the call is only significant when isActive() ==
 122 //             // false.
 123             if( !isActive() )
 124                 endAnimation();
 125         }
 126
 127         void ActivityBase::end()
 128         {
 129             if (!isActive() || isDisposed())
 130                 return;
 131             // assure animation is started:
 132             if (mbFirstPerformCall) {
 133                 mbFirstPerformCall = false;
 134                 // notify derived classes that we're starting now
 135                 startAnimation();
 136             }
 137
 138             performEnd(); // calling private virtual
 139             endAnimation();
 140             endActivity();
 141         }
 142
 143         double ActivityBase::calcAcceleratedTime( double nT ) const
 144         {
 145             // Handle acceleration/deceleration
 146             // ================================
 147
 148             // clamp nT to permissible [0,1] range
 149             nT = std::clamp( nT, 0.0, 1.0 );
 150
 151             // take acceleration/deceleration into account. if the sum
 152             // of mnAccelerationFraction and mnDecelerationFraction
 153             // exceeds 1.0, ignore both (that's according to SMIL spec)
 154             if( (mnAccelerationFraction > 0.0 ||
 155                  mnDecelerationFraction > 0.0) &&
 156                 mnAccelerationFraction + mnDecelerationFraction <= 1.0 )
 157             {
 158                 /*
 159                 // calc accelerated/decelerated time.
 160
 161                 // We have three intervals:
 162                 // 1 [0,a]
 163                 // 2 [a,d]
 164                 // 3 [d,1] (with a and d being acceleration/deceleration
 165                 // fraction, resp.)
 166
 167                 // The change rate during interval 1 is constantly
 168                 // increasing, reaching 1 at a. It then stays at 1,
 169                 // starting a linear decrease at d, ending with 0 at
 170                 // time 1. The integral of this function is the
 171                 // required new time nT'.
 172
 173                 // As we arbitrarily assumed 1 as the upper value of
 174                 // the change rate, the integral must be normalized to
 175                 // reach nT'=1 at the end of the interval. This
 176                 // normalization constant is:
 177
 178                 // c = 1 - 0.5a - 0.5d
 179
 180                 // The integral itself then amounts to:
 181
 182                 // 0.5 nT^2 / a + (nT-a) + (nT - 0.5 nT^2 / d)
 183
 184                 // (where each of the three summands correspond to the
 185                 // three intervals above, and are applied only if nT
 186                 // has reached the corresponding interval)
 187
 188                 // The graph of the change rate is a trapezoid:
 189
 190                 //   |
 191                 //  1|      /--------------\
 192                 //   |     /                \
 193                 //   |    /                  \
 194                 //   |   /                    \
 195                 //   -----------------------------
 196                 //      0   a              d  1
 197
 198                 //*/
 199                 const double nC( 1.0 - 0.5*mnAccelerationFraction - 0.5*mnDecelerationFraction );
 200
 201                 // this variable accumulates the new time value
 202                 double nTPrime(0.0);
 203
 204                 if( nT < mnAccelerationFraction )
 205                 {
 206                     nTPrime += 0.5*nT*nT/mnAccelerationFraction; // partial first interval
 207                 }
 208                 else
 209                 {
 210                     nTPrime += 0.5*mnAccelerationFraction; // full first interval
 211
 212                     if( nT <= 1.0-mnDecelerationFraction )
 213                     {
 214                         nTPrime += nT-mnAccelerationFraction; // partial second interval
 215                     }
 216                     else
 217                     {
 218                         nTPrime += 1.0 - mnAccelerationFraction - mnDecelerationFraction; // full second interval
 219
 220                         const double nTRelative( nT - 1.0 + mnDecelerationFraction );
 221
 222                         nTPrime += nTRelative - 0.5*nTRelative*nTRelative / mnDecelerationFraction;
 223                     }
 224                 }
 225
 226                 // normalize, and assign to work variable
 227                 nT = nTPrime / nC;
 228             }
 229
 230             return nT;
 231         }
 232 }
 233
 234 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */