1 #ifndef __DALI_TOOLKIT_SCROLL_VIEW_TWIST_EFFECT_H__
2 #define __DALI_TOOLKIT_SCROLL_VIEW_TWIST_EFFECT_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/public-api/animation/alpha-functions.h>
25 #include <dali-toolkit/public-api/controls/scrollable/scroll-view/scroll-view-effect.h>
35 class ScrollViewEffect;
37 namespace Internal DALI_INTERNAL
39 class ScrollViewTwistEffect;
43 * @brief ScrollView effect that twists pages onto screen when transitioning.
45 class DALI_IMPORT_API ScrollViewTwistEffect : public ScrollViewEffect
50 static const float DEFAULT_MINIMUM_DISTANCE_FOR_SHRINK; ///< The min distance for shrink
55 * @brief Create an initialized ScrollViewTwistEffect.
57 * @return A handle to a newly allocated Dali resource.
59 static ScrollViewTwistEffect New();
62 * @brief Create an uninitialized ScrollViewTwistEffect; this can be initialized with ScrollViewTwistEffect::New().
64 * Calling member functions with an uninitialized Toolkit::ScrollViewTwistEffect is not allowed.
66 ScrollViewTwistEffect();
69 * @brief Downcast an Object handle to ScrollViewTwistEffect.
71 * If handle points to a ScrollViewTwistEffect the
72 * downcast produces valid handle. If not the returned handle is left uninitialized.
73 * @param[in] handle Handle to an object
74 * @return handle to a ScrollViewTwistEffect or an uninitialized handle
76 static ScrollViewTwistEffect DownCast( BaseHandle handle );
79 * @brief Gets the minimum animation distance for the shrink effect to
82 * @return The minimum distance in seconds is returned.
84 float GetMinimumDistanceForShrink() const;
87 * @brief Sets the minimum animation distance for the shrink effect
90 * @param[in] distance The minimum distance in pixels (default = 0.0)
91 * i.e. any flick will result in shrinking.
93 void SetMinimumDistanceForShrink(float distance);
96 * @brief Enable or disable this effect.
98 * @param[in] enableFlag Set to true if the effect should be enabled.
100 void EnableEffect(bool enableFlag);
103 * @brief Manually apply effect to an Actor.
105 * @param[in] child The child Actor to be affected by this effect.
106 * @param[in] additionalEffects Whether just the basic effect (delay)
107 * should be applied. Or all effects (delay, rotation, scaling).
108 * For all effects set to true. Default is true i.e. apply all effects.
109 * @param[in] angleSwing The maximum amount the child actor should
110 * rotate in radians for each axis (X and Y) if the scrollview reaches
111 * overshoot. Default is PI/2 i.e. 90 degrees rotation.
112 * @param[in] scaleAmount The relative amount to shrink Actors as they
113 * are panned fast (flick animation). default is 0.125 (12.5% shrinkage)
114 * @param[in] delayMin The minimum delay coefficient for Actors at the
115 * scroll-view center. Set to 0 for instantaneous, and 1 for infinite delay.
117 * @param[in] delayMax The maximum delay coefficient for Actors at the
118 * scroll-view approx 1 ScrollView size from the center. Set to 0 for
119 * instantaneous, and 1 for infinite delay. Default is 0.9f (a slight delay)
121 void ApplyToActor( Actor child,
122 bool additionalEffects = true,
123 const Vector2& angleSwing = Vector2( Math::PI_4, Math::PI_4 ),
124 float scaleAmount = 0.125f,
125 float delayMin = 0.0f,
126 float delayMax = 0.9f );
129 * @brief Set the maximum swing angle when at zero drop off.
131 * @param[in] maxSwingAngle maximum swing angle for x and y axes
133 void SetMaxSwingAngle(const Vector2& maxSwingAngle);
136 * @brief Retrieve the maximum swing angle when at zero drop off.
138 * @return The maximum swing angle for x and y axes
140 Vector2 GetMaxSwingAngle() const;
143 * @brief Set the drop off values to affect the amount of swing
144 * angle applied to an actor the further it is from the scroll
147 * A drop off of 0.0f means no angle drop off while 1.0f will reduce
148 * the angle to zero over the distance supplied for that axis.
150 * Example maxSwingAngle.x is Pi, dropOff.x is 0.5f and distance.x is 100.0f:
151 * The angle on the x axis will reduce to (0.5f * Pi) over 100 pixels
153 * @param[in] dropOff amount to reduce swing angle by in the range [0.0f, 1.0f]. 0.0f
154 * @param[in] distance distance to apply dropOff in pixels
155 * @param[in] function Alpha Function to affect how drop off is applied over distance, NULL for linear application
157 void SetSwingDropOff(const Vector2& dropOff, const Vector2& distance, AlphaFunction function = NULL);
160 * @brief Get the drop off values that affect the amount of swing angle that is applied to an actor.
162 * @param[out] dropOff The current drop-off amount.
163 * @param[out] distance The current distance to apply drop-off in pixels.
164 * @param[out] function The current alpha function used to affect how the drop iff is applied over the distance.
166 void GetSwingDropOff( Vector2& dropOff, Vector2& distance, AlphaFunction& function ) const;
171 * @brief This constructor is used by Dali New() methods.
173 * @param [in] impl A pointer to a newly allocated Dali resource
175 explicit DALI_INTERNAL ScrollViewTwistEffect(Internal::ScrollViewTwistEffect *impl);
179 } // namespace Toolkit
183 #endif // __DALI_TOOLKIT_SCROLL_VIEW_TWIST_EFFECT_H__