1 #ifndef __DALI_INTERNAL_SCENE_GRAPH_PAN_GESTURE_H__
2 #define __DALI_INTERNAL_SCENE_GRAPH_PAN_GESTURE_H__
5 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
11 * http://www.apache.org/licenses/LICENSE-2.0
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
22 #include <dali/devel-api/threading/mutex.h>
23 #include <dali/public-api/common/vector-wrapper.h>
24 #include <dali/public-api/events/pan-gesture.h>
25 #include <dali/internal/update/common/property-owner.h>
26 #include <dali/internal/update/gestures/gesture-properties.h>
36 struct PanGestureProfiling;
42 * The latest pan gesture information is stored in this scene object.
44 class PanGesture : public PropertyOwner
57 SMOOTHING_NONE, // No smoothing.
58 SMOOTHING_LAST_VALUE, // Smooth between last value and latest value.
59 SMOOTHING_MULTI_TAP, // Uses multitap smoothing, only available with Prediction mode 2.
62 static const PredictionMode DEFAULT_PREDICTION_MODE;
63 static const int NUM_PREDICTION_MODES;
65 static const SmoothingMode DEFAULT_SMOOTHING_MODE;
66 static const int NUM_SMOOTHING_MODES;
68 // Latest Pan Information
71 * Only stores the information we actually require from Dali::PanGesture
76 * Stores the velocity, displacement and position.
87 Info( const Info& rhs )
88 : velocity( rhs.velocity ),
89 displacement( rhs.displacement ),
90 position( rhs.position )
97 Info& operator=( const Info& rhs )
99 velocity = rhs.velocity;
100 displacement = rhs.displacement;
101 position = rhs.position;
109 Vector2 displacement;
118 state( Gesture::Clear ),
126 PanInfo( const PanInfo& rhs )
130 screen( rhs.screen ),
136 * Assignment operator
138 PanInfo& operator=( const PanInfo& rhs )
149 * Assignment operator
150 * @param[in] gesture A Dali::Gesture
152 PanInfo& operator=( const Dali::PanGesture& rhs )
157 local.velocity = rhs.velocity;
158 local.displacement = rhs.displacement;
159 local.position = rhs.position;
161 screen.velocity = rhs.screenVelocity;
162 screen.displacement = rhs.screenDisplacement;
163 screen.position = rhs.screenPosition;
170 Gesture::State state;
176 typedef std::vector<PanInfo> PanInfoHistory;
177 typedef PanInfoHistory::iterator PanInfoHistoryIter;
178 typedef PanInfoHistory::const_iterator PanInfoHistoryConstIter;
181 static const unsigned int PAN_GESTURE_HISTORY = 30u;
186 * Create a new PanGesture
188 static PanGesture* New();
193 virtual ~PanGesture();
196 * Adds a PanGesture to the internal circular-buffer waiting to be handled by UpdateProperties.
197 * @param[in] gesture The latest pan gesture.
199 void AddGesture( const Dali::PanGesture& gesture );
202 * @brief Removes pan events from the history that are older than maxAge, leaving at least minEvents
204 * @param[in] panHistory The pan event history container
205 * @param[in] currentTime The current frame time
206 * @param[in] maxAge Maximum age of an event before removing (in millis)
207 * @param[in] minEvents The minimum number of events to leave in history, oldest events are removed before newest
209 void RemoveOldHistory(PanInfoHistory& panHistory, unsigned int currentTime, unsigned int maxAge, unsigned int minEvents);
212 * Uses elapsed time and time stamps
214 void PredictionMode1(int eventsThisFrame, PanInfo& gestureOut, PanInfoHistory& panHistory, unsigned int lastVSyncTime, unsigned int nextVSyncTime);
217 * Blends two points together.
218 * The blend value ranges are:
219 * 0.0f = use 100% of current value.
220 * 1.0f = use half-way average of current and last value.
222 * @param[in,out] gesture Pass in current gesture, outputs result of blend.
223 * @param[in] lastGesture Pass in gesture to blend between.
225 void BlendPoints( PanInfo& gesture, PanInfo& lastGesture, float blendValue );
228 * Called by the update manager so that we can update the value of our properties.
229 * @param[in] nextRenderTime The estimated time of the next render (in milliseconds).
230 * @return true, if properties were updated.
232 virtual bool UpdateProperties( unsigned int lastRenderTime, unsigned int nextRenderTime );
235 * Retrieves a reference to the panning flag property.
236 * @return The panning flag property.
238 const GesturePropertyBool& GetPanningProperty() const;
241 * Retrieves a reference to the screen position property.
242 * @return The screen position property.
244 const GesturePropertyVector2& GetScreenPositionProperty() const;
247 * Retrieves a reference to the screen velocity property.
248 * @return The screen velocity property.
250 const GesturePropertyVector2& GetScreenVelocityProperty() const;
253 * Retrieves a reference to the screen displacement property.
254 * @return The screen displacement property.
256 const GesturePropertyVector2& GetScreenDisplacementProperty() const;
259 * Retrieves a reference to the local position property.
260 * @return The local position property.
262 const GesturePropertyVector2& GetLocalPositionProperty() const;
265 * Retrieves a reference to the local displacement property.
266 * @return The local displacement property.
268 const GesturePropertyVector2& GetLocalDisplacementProperty() const;
271 * Retrieves a reference to the local velocity property.
272 * @return The local velocity property.
274 const GesturePropertyVector2& GetLocalVelocityProperty() const;
277 * @brief Sets the prediction mode of the pan gesture
279 * @param[in] mode The prediction mode
281 void SetPredictionMode(PredictionMode mode);
284 * @brief Sets the prediction amount of the pan gesture
286 * @param[in] amount The prediction amount in milliseconds
288 void SetPredictionAmount(unsigned int amount);
291 * @brief Sets the upper bound of the prediction amount for clamping
293 * @param[in] amount The prediction amount in milliseconds
295 void SetMaximumPredictionAmount(unsigned int amount);
298 * @brief Sets the lower bound of the prediction amount for clamping
300 * @param[in] amount The prediction amount in milliseconds
302 void SetMinimumPredictionAmount(unsigned int amount);
305 * @brief Sets the amount of prediction interpolation to adjust when the pan velocity is changed
307 * @param[in] amount The prediction amount in milliseconds
309 void SetPredictionAmountAdjustment(unsigned int amount);
312 * @brief Sets the prediction mode of the pan gesture
314 * @param[in] mode The prediction mode
316 void SetSmoothingMode(SmoothingMode mode);
319 * @brief Sets the amount of smoothing to apply for the current smoothing mode
321 * @param[in] amount The amount of smoothing [0.0f,1.0f]
323 void SetSmoothingAmount(float amount);
326 * @brief Sets whether to use actual times of the real gesture and frames or not.
328 * @param[in] value True = use actual times, False = use perfect values
330 void SetUseActualTimes( bool value );
333 * @brief Sets the interpolation time range (ms) of past points to use (with weights) when interpolating.
335 * @param[in] value Time range in ms
337 void SetInterpolationTimeRange( int value );
340 * @brief Sets whether to use scalar only prediction, which when enabled, ignores acceleration.
342 * @param[in] value True = use scalar prediction only
344 void SetScalarOnlyPredictionEnabled( bool value );
347 * @brief Sets whether to use two point prediction. This combines two interpolated points to get more steady acceleration and velocity values.
349 * @param[in] value True = use two point prediction
351 void SetTwoPointPredictionEnabled( bool value );
354 * @brief Sets the time in the past to interpolate the second point when using two point interpolation.
356 * @param[in] value Time in past in ms
358 void SetTwoPointInterpolatePastTime( int value );
361 * @brief Sets the two point velocity bias. This is the ratio of first and second points to use for velocity.
363 * @param[in] value 0.0f = 100% first point. 1.0f = 100% of second point.
365 void SetTwoPointVelocityBias( float value );
368 * @brief Sets the two point acceleration bias. This is the ratio of first and second points to use for acceleration.
370 * @param[in] value 0.0f = 100% first point. 1.0f = 100% of second point.
372 void SetTwoPointAccelerationBias( float value );
375 * @brief Sets the range of time (ms) of points in the history to perform multitap smoothing with (if enabled).
377 * @param[in] value Time in past in ms
379 void SetMultitapSmoothingRange( int value );
382 * Called to provide pan-gesture profiling information.
384 void EnableProfiling();
389 * Protected constructor.
394 PanGesture(const PanGesture&);
398 // Struct to keep pairs of local and screen data together.
399 // TODO: This can encapsulate some functionality also.
407 * Houses new code to process input events and generate an output point.
409 * @param[in] lastVSyncTime The time of the last render (in milliseconds)
410 * @param[in] nextVSyncTime The estimated time of the next render (in milliseconds)
412 bool NewAlgorithm( unsigned int lastVSyncTime, unsigned int nextVSyncTime );
415 * Gets the (absolute) time difference between two times.
416 * This is limited by minimumDelta, so it can be safe to use as a divisor.
417 * This function is wrapped so that the behviour can be overridden to return a "perfect" time difference (overrideDifference).
419 * @param[in] timeA The first time to calculate from
420 * @param[in] timeB The second time to calculate from
421 * @param[in] minimumDelta The smallest amount the difference can become
422 * @param[in] overrideDifference The time difference to return if using perfect times
424 inline float GetDivisibleTimeDifference( int timeA, int timeB, float minimumDelta, float overrideDifference );
427 * This limits the change currentAcceleration can have over lastAcceleration by the specified changeLimit value.
429 * @param[in] currentAcceleration The acceleration to modify
430 * @param[in] lastAcceleration The acceleration to limit against
431 * @param[in] changeLimit The maximum change (in either direction)
433 void LimitAccelerationChange( RelativeVectors& currentAcceleration, RelativeVectors& lastAcceleration, float changeLimit );
436 * Reads all events received this frame into a linear buffer.
437 * A lock is held while this is done.
439 unsigned int ReadFrameEvents();
442 * Converts between input rate and internal rate (typically 60Hz internally).
443 * Also writes to the pan history container.
444 * TODO: Does not need to return the gesture if it is in the history also, but currently it's used.
445 * (if rate conversion does not generate a point there are points still in history, but this can been done with a bool property).
447 * @param[out] rateConvertedGesture Result gesture for this frame is writen here.
448 * @param[in] eventsThisFrame Number of events to convert
449 * @param[in] currentFrameTime Time of the frame we will render to
450 * @param[in] lastFrameTime Time of the last rendered frame
451 * @param[out] justStarted Set to true if we are now starting a new gesture
452 * @param[out] justFinished Set to true if we are now finishing a gesture
454 bool InputRateConversion( PanInfo& rateConvertedGesture, unsigned int eventsThisFrame,
455 unsigned int currentFrameTime, unsigned int lastFrameTime, bool& justStarted, bool& justFinished );
458 * Generates an interpolated point at the specified point in time.
460 * @param[in] history of points to use
461 * @param[in] currentTime Time of the frame we will render to
462 * @param[in] targetTime Time of the point to generate
463 * @param[in] range Range of time (each side of target time) to use points from
464 * @param[out] outPoint Generated point
465 * @param[out] acceleration Generated acceleration
466 * @param[in] outputTimeGranularity Time difference between output point (typically 60Hz)
467 * @param[in] eraseUnused Set to true to clean up any history not used by the function
469 bool InterpolatePoint( PanInfoHistory& history, unsigned int currentTime, unsigned int targetTime, unsigned int range,
470 PanInfo& outPoint, RelativeVectors& acceleration, int outputTimeGranularity, bool eraseUnused );
473 * Predicts a point in the future, based on the supplied point and acceleration.
474 * Other user configuration settings are considered.
476 * @param[in] startPoint Starting point to use. Position and velocity are taken from here.
477 * @param[in] accelerationToUse The acceleration to use.
478 * @param[out] predictedPoint Generated predicted point
479 * @param[in] currentFrameTime Time of the frame we will render to
480 * @param[in] previousFrameTime Time of the last rendered frame
481 * @param[in] noPreviousData Set to true if we are just starting a gesture
483 void PredictionMode2( PanInfo& startPoint, RelativeVectors& accelerationToUse,
484 PanInfo& predictedPoint, unsigned int currentFrameTime, unsigned int previousFrameTime, bool noPreviousData );
489 PanGesture& operator=(const PanGesture&);
492 virtual void ResetDefaultProperties( BufferIndex updateBufferIndex );
494 // Defines information to be gathered by the gesture reading code.
495 struct FrameGestureInfo
497 PanGesture::PanInfo frameGesture;
499 unsigned int eventsThisFrame;
504 : acceleration( 0.0f ),
505 eventsThisFrame( 0 ),
506 justStarted( false ),
507 justFinished( false )
513 * Reads gestures from input, builds history.
514 * @param[out] info Written to with information about gestures read this frame.
515 * @param[in] currentTimestamp The time of this frame.
517 bool ReadGestures( FrameGestureInfo& info, unsigned int currentTimestamp );
520 * Reads gestures from input and resamples data, builds history.
521 * @param[out] info Written to with information about gestures read this frame.
522 * @param[in] currentTimestamp The time of this frame.
524 bool ReadAndResampleGestures( FrameGestureInfo& info, unsigned int currentTimestamp );
529 GesturePropertyBool mPanning; ///< panning flag
530 GesturePropertyVector2 mScreenPosition; ///< screenPosition
531 GesturePropertyVector2 mScreenDisplacement; ///< screenDisplacement
532 GesturePropertyVector2 mScreenVelocity; ///< screenVelocity
533 GesturePropertyVector2 mLocalPosition; ///< localPosition
534 GesturePropertyVector2 mLocalDisplacement; ///< localDisplacement
535 GesturePropertyVector2 mLocalVelocity; ///< localVelocity
537 PanInfoHistory mPanHistory;
538 PanInfoHistory mPredictionHistory;
539 PanInfo mGestures[PAN_GESTURE_HISTORY]; ///< Circular buffer storing the 4 most recent gestures.
540 PanInfo mReadGestures[PAN_GESTURE_HISTORY]; ///< Linear buffer storing the most recent gestures (to reduce read lock time).
541 PanInfo mLastGesture; ///< The last gesture. (last update frame).
542 PanInfo mTargetGesture; ///< The most recent input gesture, if the current used gesture does not match.
543 PanInfo mLastUnmodifiedGesture; ///< The last gesture before any processing was done on it.
544 PanInfo mLastSecondInterpolatedPoint; ///< Stores the last second interpolated point we generated.
545 PanInfo mLastFrameReadGesture; ///< Stores the last gesture read.
546 PanInfo mLastPredictedPoint; ///< Stores the last predicted point we generated.
547 RelativeVectors mLastAcceleration; ///< Stores the acceleration value from the acceleration limiting last frame.
548 RelativeVectors mLastInterpolatedAcceleration; ///< Stores the second interpolated point acceleration value from the last frame.
549 RelativeVectors mLastInitialAcceleration; ///< Stores the initial acceleration value from the last frame.
551 volatile unsigned int mWritePosition; ///< The next PanInfo buffer to write to. (starts at 0).
552 unsigned int mReadPosition; ///< The next PanInfo buffer to read. (starts at 0).
553 bool mNotAtTarget; ///< Keeps track of if the last gesture used was the most recent received.
554 bool mInGesture; ///< True if the gesture is currently being handled i.e. between Started <-> Finished/Cancelled.
555 bool mPredictionAmountOverridden;
556 bool mSmoothingAmountOverridden;
558 PanGestureProfiling* mProfiling; ///< NULL unless pan-gesture profiling information is required.
559 Dali::Mutex mMutex; ///< Mutex to lock access.
561 // Environment variables:
563 PredictionMode mPredictionMode; ///< The pan gesture prediction mode
564 unsigned int mPredictionAmount; ///< how far into future to predict in milliseconds
565 unsigned int mCurrentPredictionAmount; ///< the current prediction amount used by the prediction algorithm
566 unsigned int mMaxPredictionAmount; ///< the maximum prediction amount used by the prediction algorithm
567 unsigned int mMinPredictionAmount; ///< the minimum prediction amount used by the prediction algorithm
568 unsigned int mPredictionAmountAdjustment; ///< the prediction amount to adjust in milliseconds when pan velocity changes
569 SmoothingMode mSmoothingMode; ///< The pan gesture prediction mode
570 float mSmoothingAmount; ///< How much smoothing to apply [0.0f,1.0f]
571 bool mUseActualTimes; ///< Disable to optionally override actual times if they make results worse.
572 int mInterpolationTimeRange; ///< Time into past history (ms) to use points to interpolate the first point.
573 bool mScalarOnlyPredictionEnabled; ///< If enabled, prediction is done using velocity alone (no integration or acceleration).
574 bool mTwoPointPredictionEnabled; ///< If enabled, a second interpolated point is predicted and combined with the first to get more stable values.
575 int mTwoPointPastInterpolateTime; ///< The target time in the past to generate the second interpolated point.
576 float mTwoPointVelocityBias; ///< The ratio of first and second interpolated points to use for velocity. 0.0f = 100% of first point. 1.0f = 100% of second point.
577 float mTwoPointAccelerationBias; ///< The ratio of first and second interpolated points to use for acceleration. 0.0f = 100% of first point. 1.0f = 100% of second point.
578 int mMultiTapSmoothingRange; ///< The range in time (ms) of points in the history to smooth the final output against.
581 } // namespace SceneGraph
583 } // namespace Internal
587 #endif // __DALI_INTERNAL_SCENE_GRAPH_PAN_GESTURE_H__