1 #ifndef DALI_INTERNAL_PAN_GESTURE_DETECTOR_BASE_H
2 #define DALI_INTERNAL_PAN_GESTURE_DETECTOR_BASE_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 <cstdint> // uint32_t
23 #include <dali/public-api/common/vector-wrapper.h>
24 #include <dali/public-api/math/vector2.h>
25 #include <dali/integration-api/events/pan-gesture-event.h>
28 #include <dali/internal/input/common/gesture-detector.h>
37 struct PanGestureRequest;
46 class EnvironmentOptions;
49 * When given a set of touch events, this detector attempts to determine if a pan gesture has taken place.
51 class PanGestureDetectorBase : public GestureDetector
58 virtual ~PanGestureDetectorBase();
63 * @copydoc Dali::Internal::GestureDetector::SendEvent(const Integration::TouchEvent&)
65 virtual void SendEvent(const Integration::TouchEvent& event);
68 * @copydoc Dali::Internal::GestureDetector::Update(const Integration::GestureRequest&)
70 virtual void Update(const Integration::GestureRequest& request);
76 * @param[in] screenSize The size of the screen.
77 * @param[in] request The details of the request.
79 PanGestureDetectorBase(Vector2 screenSize, const Integration::PanGestureRequest& request, EnvironmentOptions* environmentOptions);
84 * Emits the pan gesture event (performs some smoothing operation).
85 * @param[in] state The state of the pan.
86 * @param[in] currentEvent The latest touch event.
88 void SendPan(Gesture::State state, const Integration::TouchEvent& currentEvent);
91 * Emits the pan gesture event to the core.
92 * @param[in] gesture The pan gesture event.
94 virtual void EmitPan(const Integration::PanGestureEvent gesture) = 0;
99 * Internal state machine.
103 Clear, ///< No gesture detected.
104 Possible, ///< The current touch event data suggests that a gesture is possible.
105 Started, ///< A gesture has been detected.
106 Finished, ///< A previously started pan gesture has finished.
107 Failed, ///< Current touch event data suggests a pan gesture is not possible.
110 State mState; ///< The current state of the detector.
111 std::vector<Integration::TouchEvent> mTouchEvents; ///< A container of all touch events after an initial down event.
113 Vector2 mPrimaryTouchDownLocation; ///< The initial touch down point.
114 Vector2 mThresholdAdjustmentPerFrame; ///< The adjustment per frame at the start of a slow pan.
115 Vector2 mPreviousPosition; ///< The previous position.
117 unsigned int mThresholdAdjustmentsRemaining; ///< No. of threshold adjustments still to apply (for a slow-pan).
118 unsigned int mThresholdTotalAdjustments; ///< The total number of adjustments required.
120 uint32_t mPrimaryTouchDownTime; ///< The initial touch down time.
121 unsigned int mMinimumTouchesRequired; ///< The minimum touches required before a pan should be emitted.
122 unsigned int mMaximumTouchesRequired; ///< The maximum touches after which a pan should not be emitted.
124 unsigned int mMinimumDistanceSquared; ///< The minimum distance squared before pan should start.
125 unsigned int mMinimumMotionEvents; ///< The minimum motion events before pan should start.
126 unsigned int mMotionEvents; ///< The motion events received so far (before pan is emitted).
129 } // namespace Adaptor
131 } // namespace Internal
135 #endif // DALI_INTERNAL_PAN_GESTURE_DETECTOR_BASE_H