1 #ifndef DALI_INTERNAL_SCENE_GRAPH_PAN_GESTURE_H
2 #define DALI_INTERNAL_SCENE_GRAPH_PAN_GESTURE_H
5 * Copyright (c) 2019 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 )
101 velocity = rhs.velocity;
102 displacement = rhs.displacement;
103 position = rhs.position;
112 Vector2 displacement;
121 state( Gesture::Clear ),
129 PanInfo( const PanInfo& rhs )
133 screen( rhs.screen ),
139 * Assignment operator
141 PanInfo& operator=( const PanInfo& rhs )
156 * Assignment operator
157 * @param[in] gesture A Dali::Gesture
159 PanInfo& operator=( const Dali::PanGesture& rhs )
164 local.velocity = rhs.velocity;
165 local.displacement = rhs.displacement;
166 local.position = rhs.position;
168 screen.velocity = rhs.screenVelocity;
169 screen.displacement = rhs.screenDisplacement;
170 screen.position = rhs.screenPosition;
177 Gesture::State state;
183 typedef std::vector<PanInfo> PanInfoHistory;
184 typedef PanInfoHistory::iterator PanInfoHistoryIter;
185 typedef PanInfoHistory::const_iterator PanInfoHistoryConstIter;
188 static const unsigned int PAN_GESTURE_HISTORY = 30u;
193 * Create a new PanGesture
195 static PanGesture* New();
200 virtual ~PanGesture();
203 * Adds a PanGesture to the internal circular-buffer waiting to be handled by UpdateProperties.
204 * @param[in] gesture The latest pan gesture.
206 void AddGesture( const Dali::PanGesture& gesture );
209 * @brief Removes pan events from the history that are older than maxAge, leaving at least minEvents
211 * @param[in] panHistory The pan event history container
212 * @param[in] currentTime The current frame time
213 * @param[in] maxAge Maximum age of an event before removing (in millis)
214 * @param[in] minEvents The minimum number of events to leave in history, oldest events are removed before newest
216 void RemoveOldHistory(PanInfoHistory& panHistory, unsigned int currentTime, unsigned int maxAge, unsigned int minEvents);
219 * Uses elapsed time and time stamps
221 void PredictionMode1(int eventsThisFrame, PanInfo& gestureOut, PanInfoHistory& panHistory, unsigned int lastVSyncTime, unsigned int nextVSyncTime);
224 * Blends two points together.
225 * The blend value ranges are:
226 * 0.0f = use 100% of current value.
227 * 1.0f = use half-way average of current and last value.
229 * @param[in,out] gesture Pass in current gesture, outputs result of blend.
230 * @param[in] lastGesture Pass in gesture to blend between.
232 void BlendPoints( PanInfo& gesture, PanInfo& lastGesture, float blendValue );
235 * Called by the update manager so that we can update the value of our properties.
236 * @param[in] nextRenderTime The estimated time of the next render (in milliseconds).
237 * @return true, if properties were updated.
239 bool UpdateProperties( unsigned int lastRenderTime, unsigned int nextRenderTime );
242 * Retrieves a reference to the panning flag property.
243 * @return The panning flag property.
245 const GesturePropertyBool& GetPanningProperty() const;
248 * Retrieves a reference to the screen position property.
249 * @return The screen position property.
251 const GesturePropertyVector2& GetScreenPositionProperty() const;
254 * Retrieves a reference to the screen velocity property.
255 * @return The screen velocity property.
257 const GesturePropertyVector2& GetScreenVelocityProperty() const;
260 * Retrieves a reference to the screen displacement property.
261 * @return The screen displacement property.
263 const GesturePropertyVector2& GetScreenDisplacementProperty() const;
266 * Retrieves a reference to the local position property.
267 * @return The local position property.
269 const GesturePropertyVector2& GetLocalPositionProperty() const;
272 * Retrieves a reference to the local displacement property.
273 * @return The local displacement property.
275 const GesturePropertyVector2& GetLocalDisplacementProperty() const;
278 * Retrieves a reference to the local velocity property.
279 * @return The local velocity property.
281 const GesturePropertyVector2& GetLocalVelocityProperty() const;
284 * @brief Sets the prediction mode of the pan gesture
286 * @param[in] mode The prediction mode
288 void SetPredictionMode(PredictionMode mode);
291 * @brief Sets the prediction amount of the pan gesture
293 * @param[in] amount The prediction amount in milliseconds
295 void SetPredictionAmount(unsigned int amount);
298 * @brief Sets the upper bound of the prediction amount for clamping
300 * @param[in] amount The prediction amount in milliseconds
302 void SetMaximumPredictionAmount(unsigned int amount);
305 * @brief Sets the lower bound of the prediction amount for clamping
307 * @param[in] amount The prediction amount in milliseconds
309 void SetMinimumPredictionAmount(unsigned int amount);
312 * @brief Sets the amount of prediction interpolation to adjust when the pan velocity is changed
314 * @param[in] amount The prediction amount in milliseconds
316 void SetPredictionAmountAdjustment(unsigned int amount);
319 * @brief Sets the prediction mode of the pan gesture
321 * @param[in] mode The prediction mode
323 void SetSmoothingMode(SmoothingMode mode);
326 * @brief Sets the amount of smoothing to apply for the current smoothing mode
328 * @param[in] amount The amount of smoothing [0.0f,1.0f]
330 void SetSmoothingAmount(float amount);
333 * @brief Sets whether to use actual times of the real gesture and frames or not.
335 * @param[in] value True = use actual times, False = use perfect values
337 void SetUseActualTimes( bool value );
340 * @brief Sets the interpolation time range (ms) of past points to use (with weights) when interpolating.
342 * @param[in] value Time range in ms
344 void SetInterpolationTimeRange( int value );
347 * @brief Sets whether to use scalar only prediction, which when enabled, ignores acceleration.
349 * @param[in] value True = use scalar prediction only
351 void SetScalarOnlyPredictionEnabled( bool value );
354 * @brief Sets whether to use two point prediction. This combines two interpolated points to get more steady acceleration and velocity values.
356 * @param[in] value True = use two point prediction
358 void SetTwoPointPredictionEnabled( bool value );
361 * @brief Sets the time in the past to interpolate the second point when using two point interpolation.
363 * @param[in] value Time in past in ms
365 void SetTwoPointInterpolatePastTime( int value );
368 * @brief Sets the two point velocity bias. This is the ratio of first and second points to use for velocity.
370 * @param[in] value 0.0f = 100% first point. 1.0f = 100% of second point.
372 void SetTwoPointVelocityBias( float value );
375 * @brief Sets the two point acceleration bias. This is the ratio of first and second points to use for acceleration.
377 * @param[in] value 0.0f = 100% first point. 1.0f = 100% of second point.
379 void SetTwoPointAccelerationBias( float value );
382 * @brief Sets the range of time (ms) of points in the history to perform multitap smoothing with (if enabled).
384 * @param[in] value Time in past in ms
386 void SetMultitapSmoothingRange( int value );
389 * Called to provide pan-gesture profiling information.
391 void EnableProfiling();
394 * Reset default properties, custom ones not supported due to this being the only object in scene side
395 * @param updateBufferIndex index to use
397 void ResetDefaultProperties( BufferIndex updateBufferIndex );
402 * Protected constructor.
407 PanGesture(const PanGesture&);
411 // Struct to keep pairs of local and screen data together.
412 // TODO: This can encapsulate some functionality also.
420 * Houses new code to process input events and generate an output point.
422 * @param[in] lastVSyncTime The time of the last render (in milliseconds)
423 * @param[in] nextVSyncTime The estimated time of the next render (in milliseconds)
425 bool NewAlgorithm( unsigned int lastVSyncTime, unsigned int nextVSyncTime );
428 * Gets the (absolute) time difference between two times.
429 * This is limited by minimumDelta, so it can be safe to use as a divisor.
430 * This function is wrapped so that the behviour can be overridden to return a "perfect" time difference (overrideDifference).
432 * @param[in] timeA The first time to calculate from
433 * @param[in] timeB The second time to calculate from
434 * @param[in] minimumDelta The smallest amount the difference can become
435 * @param[in] overrideDifference The time difference to return if using perfect times
437 inline float GetDivisibleTimeDifference( int timeA, int timeB, float minimumDelta, float overrideDifference );
440 * This limits the change currentAcceleration can have over lastAcceleration by the specified changeLimit value.
442 * @param[in] currentAcceleration The acceleration to modify
443 * @param[in] lastAcceleration The acceleration to limit against
444 * @param[in] changeLimit The maximum change (in either direction)
446 void LimitAccelerationChange( RelativeVectors& currentAcceleration, RelativeVectors& lastAcceleration, float changeLimit );
449 * Reads all events received this frame into a linear buffer.
450 * A lock is held while this is done.
452 unsigned int ReadFrameEvents();
455 * Converts between input rate and internal rate (typically 60Hz internally).
456 * Also writes to the pan history container.
457 * TODO: Does not need to return the gesture if it is in the history also, but currently it's used.
458 * (if rate conversion does not generate a point there are points still in history, but this can been done with a bool property).
460 * @param[out] rateConvertedGesture Result gesture for this frame is writen here.
461 * @param[in] eventsThisFrame Number of events to convert
462 * @param[in] currentFrameTime Time of the frame we will render to
463 * @param[in] lastFrameTime Time of the last rendered frame
464 * @param[out] justStarted Set to true if we are now starting a new gesture
465 * @param[out] justFinished Set to true if we are now finishing a gesture
467 bool InputRateConversion( PanInfo& rateConvertedGesture, unsigned int eventsThisFrame,
468 unsigned int currentFrameTime, unsigned int lastFrameTime, bool& justStarted, bool& justFinished );
471 * Generates an interpolated point at the specified point in time.
473 * @param[in] history of points to use
474 * @param[in] currentTime Time of the frame we will render to
475 * @param[in] targetTime Time of the point to generate
476 * @param[in] range Range of time (each side of target time) to use points from
477 * @param[out] outPoint Generated point
478 * @param[out] acceleration Generated acceleration
479 * @param[in] outputTimeGranularity Time difference between output point (typically 60Hz)
480 * @param[in] eraseUnused Set to true to clean up any history not used by the function
482 bool InterpolatePoint( PanInfoHistory& history, unsigned int currentTime, unsigned int targetTime, unsigned int range,
483 PanInfo& outPoint, RelativeVectors& acceleration, int outputTimeGranularity, bool eraseUnused );
486 * Predicts a point in the future, based on the supplied point and acceleration.
487 * Other user configuration settings are considered.
489 * @param[in] startPoint Starting point to use. Position and velocity are taken from here.
490 * @param[in] accelerationToUse The acceleration to use.
491 * @param[out] predictedPoint Generated predicted point
492 * @param[in] currentFrameTime Time of the frame we will render to
493 * @param[in] previousFrameTime Time of the last rendered frame
494 * @param[in] noPreviousData Set to true if we are just starting a gesture
496 void PredictionMode2( PanInfo& startPoint, RelativeVectors& accelerationToUse,
497 PanInfo& predictedPoint, unsigned int currentFrameTime, unsigned int previousFrameTime, bool noPreviousData );
502 PanGesture& operator=(const PanGesture&);
504 // Defines information to be gathered by the gesture reading code.
505 struct FrameGestureInfo
507 PanGesture::PanInfo frameGesture;
509 unsigned int eventsThisFrame;
514 : acceleration( 0.0f ),
515 eventsThisFrame( 0 ),
516 justStarted( false ),
517 justFinished( false )
523 * Reads gestures from input, builds history.
524 * @param[out] info Written to with information about gestures read this frame.
525 * @param[in] currentTimestamp The time of this frame.
527 bool ReadGestures( FrameGestureInfo& info, unsigned int currentTimestamp );
530 * Reads gestures from input and resamples data, builds history.
531 * @param[out] info Written to with information about gestures read this frame.
532 * @param[in] currentTimestamp The time of this frame.
534 bool ReadAndResampleGestures( FrameGestureInfo& info, unsigned int currentTimestamp );
539 GesturePropertyBool mPanning; ///< panning flag
540 GesturePropertyVector2 mScreenPosition; ///< screenPosition
541 GesturePropertyVector2 mScreenDisplacement; ///< screenDisplacement
542 GesturePropertyVector2 mScreenVelocity; ///< screenVelocity
543 GesturePropertyVector2 mLocalPosition; ///< localPosition
544 GesturePropertyVector2 mLocalDisplacement; ///< localDisplacement
545 GesturePropertyVector2 mLocalVelocity; ///< localVelocity
547 PanInfoHistory mPanHistory;
548 PanInfoHistory mPredictionHistory;
549 PanInfo mGestures[PAN_GESTURE_HISTORY]; ///< Circular buffer storing the 4 most recent gestures.
550 PanInfo mReadGestures[PAN_GESTURE_HISTORY]; ///< Linear buffer storing the most recent gestures (to reduce read lock time).
551 PanInfo mLastGesture; ///< The last gesture. (last update frame).
552 PanInfo mTargetGesture; ///< The most recent input gesture, if the current used gesture does not match.
553 PanInfo mLastUnmodifiedGesture; ///< The last gesture before any processing was done on it.
554 PanInfo mLastSecondInterpolatedPoint; ///< Stores the last second interpolated point we generated.
555 PanInfo mLastFrameReadGesture; ///< Stores the last gesture read.
556 PanInfo mLastPredictedPoint; ///< Stores the last predicted point we generated.
557 RelativeVectors mLastAcceleration; ///< Stores the acceleration value from the acceleration limiting last frame.
558 RelativeVectors mLastInterpolatedAcceleration; ///< Stores the second interpolated point acceleration value from the last frame.
559 RelativeVectors mLastInitialAcceleration; ///< Stores the initial acceleration value from the last frame.
561 volatile unsigned int mWritePosition; ///< The next PanInfo buffer to write to. (starts at 0).
562 unsigned int mReadPosition; ///< The next PanInfo buffer to read. (starts at 0).
563 bool mNotAtTarget; ///< Keeps track of if the last gesture used was the most recent received.
564 bool mInGesture; ///< True if the gesture is currently being handled i.e. between Started <-> Finished/Cancelled.
565 bool mPredictionAmountOverridden;
566 bool mSmoothingAmountOverridden;
568 PanGestureProfiling* mProfiling; ///< NULL unless pan-gesture profiling information is required.
569 Dali::Mutex mMutex; ///< Mutex to lock access.
571 // Environment variables:
573 PredictionMode mPredictionMode; ///< The pan gesture prediction mode
574 unsigned int mPredictionAmount; ///< how far into future to predict in milliseconds
575 unsigned int mCurrentPredictionAmount; ///< the current prediction amount used by the prediction algorithm
576 unsigned int mMaxPredictionAmount; ///< the maximum prediction amount used by the prediction algorithm
577 unsigned int mMinPredictionAmount; ///< the minimum prediction amount used by the prediction algorithm
578 unsigned int mPredictionAmountAdjustment; ///< the prediction amount to adjust in milliseconds when pan velocity changes
579 SmoothingMode mSmoothingMode; ///< The pan gesture prediction mode
580 float mSmoothingAmount; ///< How much smoothing to apply [0.0f,1.0f]
581 bool mUseActualTimes; ///< Disable to optionally override actual times if they make results worse.
582 int mInterpolationTimeRange; ///< Time into past history (ms) to use points to interpolate the first point.
583 bool mScalarOnlyPredictionEnabled; ///< If enabled, prediction is done using velocity alone (no integration or acceleration).
584 bool mTwoPointPredictionEnabled; ///< If enabled, a second interpolated point is predicted and combined with the first to get more stable values.
585 int mTwoPointPastInterpolateTime; ///< The target time in the past to generate the second interpolated point.
586 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.
587 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.
588 int mMultiTapSmoothingRange; ///< The range in time (ms) of points in the history to smooth the final output against.
591 } // namespace SceneGraph
593 } // namespace Internal
597 #endif // DALI_INTERNAL_SCENE_GRAPH_PAN_GESTURE_H