1 #ifndef __DALI_PAN_GESTURE_H__
2 #define __DALI_PAN_GESTURE_H__
5 * Copyright (c) 2015 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/public-api/events/gesture.h>
23 #include <dali/public-api/math/vector2.h>
29 * @brief A PanGesture is emitted when the user moves one or more fingers in a particular direction.
31 * This gesture can be in one of three states, when the pan gesture is first detected: "Started";
32 * when the pan gesture is continuing: "Continuing"; and finally, when the pan gesture ends:
35 * A pan gesture will end in the following ways:
36 * - User releases the primary finger (the first touch).
37 * - User has more fingers on the screen than the maximum specified.
38 * - User has less fingers on the screen than the minimum specified.
39 * - Cancelled by the system.
41 * A pan gesture will continue to be sent to the actor under than initial pan until it ends.
43 struct DALI_IMPORT_API PanGesture: public Gesture
45 // Construction & Destruction
48 * @brief Default Constructor.
55 * @param[in] state The state of the gesture
57 PanGesture(Gesture::State state);
60 * @brief Copy constructor.
62 PanGesture( const PanGesture& rhs );
65 * @brief Assignment operator.
67 PanGesture& operator=( const PanGesture& rhs );
70 * @brief Virtual destructor.
72 virtual ~PanGesture();
77 * @brief The velocity at which the user is moving their fingers.
79 * This is represented as a Vector2 and is the pixel movement per millisecond.
80 * A positive x value shows that the user is panning to the right, a negative x value means the opposite.
81 * A positive y value shows that the user is panning downwards, a negative y values means upwards.
82 * This value represents the local coordinates of the actor attached to the PanGestureDetector.
87 * @brief This is a Vector2 showing how much the user has panned (dragged) since the last pan gesture or,
88 * if the gesture has just started, then the amount panned since the user touched the screen.
90 * A positive x value shows that the user is panning to the right, a negative x value means the opposite.
91 * A positive y value shows that the user is panning downwards, a negative y value means upwards.
92 * This value is in local actor coordinates, the actor being the one attached to the
98 * @brief This current touch position of the primary touch point in local actor coordinates.
103 * @brief The velocity at which the user is moving their fingers.
105 * This is represented as a Vector2 and is the pixel movement per millisecond.
106 * A positive x value shows that the user is panning to the right, a negative x value means the opposite.
107 * A positive y value shows that the user is panning downwards, a negative y values means upwards.
108 * This value represents the screen coordinates.
110 Vector2 screenVelocity;
113 * @brief This is a Vector2 showing how much the user has panned (dragged) since the last pan gesture or,
114 * if the gesture has just started, then the amount panned since the user touched the screen.
116 * A positive x value shows that the user is panning to the right, a negative x value means the opposite.
117 * A positive y value shows that the user is panning downwards, a negative y value means upwards.
118 * This value is in screen coordinates.
120 Vector2 screenDisplacement;
123 * @brief This current touch position of the primary touch point in screen coordinates.
125 Vector2 screenPosition;
128 * @brief The total number of fingers touching the screen in a pan gesture.
130 unsigned int numberOfTouches;
132 // Convenience Methods
135 * @brief Returns the speed at which the user is moving their fingers.
137 * This is the pixel movement per millisecond.
138 * @return The speed of the pan (in pixels per millisecond).
140 float GetSpeed() const;
143 * @brief This returns the distance the user has panned (dragged) since the last pan gesture or,
144 * if the gesture has just started, then the distance moved since the user touched the screen.
146 * This is always a positive value.
147 * @return The distance, as a float, a user's finger has panned.
149 float GetDistance() const;
152 * @brief Returns the speed at which the user is moving their fingers relative to screen coordinates.
154 * This is the pixel movement per millisecond.
155 * @return The speed of the pan (in pixels per millisecond).
157 float GetScreenSpeed() const;
160 * @brief This returns the distance the user has panned (dragged) since the last pan gesture in screen
161 * coordinates or, if the gesture has just started, then the distance in screen coordinates moved
162 * since the user touched the screen.
164 * This is always a positive value.
165 * @return The distance, as a float, a user's finger has panned.
167 float GetScreenDistance() const;
172 #endif // __DALI_PAN_GESTURE_H__