1 #ifndef __DALI_PATH_H__
2 #define __DALI_PATH_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/object/handle.h>
23 #include <dali/public-api/object/property-index-ranges.h>
28 namespace Internal DALI_INTERNAL
33 * @brief A 3D parametric curve
35 * Paths can be used to animate position and orientation of actors using Dali::Animate( Actor, Path, ... )
38 class DALI_IMPORT_API Path : public Handle
43 * @brief An enumeration of properties belonging to the Path class.
49 Points = DEFAULT_DERIVED_HANDLE_PROPERTY_START_INDEX, ///< name "points", type Vector3
50 ControlPoints, ///< name "control-points", type Vector3
55 * @brief Create an initialized Path handle.
57 * @return a handle to a newly allocated Dali resource.
62 * @brief Downcast an Object handle to Path handle.
64 * If handle points to a KeyFrames object the downcast produces
65 * valid handle. If not the returned handle is left uninitialized.
66 * @param[in] handle to An object
67 * @return handle to a Path object or an uninitialized handle
69 static Path DownCast( BaseHandle handle );
72 * @brief Create an uninitialized Path handle.
74 * This can be initialized with Path::New(). Calling member
75 * functions with an uninitialized Dali::Object is not allowed.
82 * This is non-virtual since derived Handle types must not contain data or virtual methods.
87 * @brief This copy constructor is required for (smart) pointer semantics.
89 * @param [in] handle A reference to the copied handle
91 Path(const Path& handle);
94 * @brief This assignment operator is required for (smart) pointer semantics.
96 * @param [in] rhs A reference to the copied handle
97 * @return A reference to this
99 Path& operator=(const Path& rhs);
102 * @brief Add an interpolation point.
104 * @param[in] point The new interpolation point to be added
106 void AddPoint(const Vector3& point );
109 * @brief Add a control point.
111 * @param[in] point The new control point to be added
113 void AddControlPoint(const Vector3& point );
116 * @brief Automatic generation of control points. Generated control points which result in a smooth join between the splines of each segment.
118 * The generating algorithm is as follows:
119 * For a given knot point K[N], find the vector that bisects K[N-1],[N] and [N],[N+1].
120 * Calculate the tangent vector by taking the normal of this bisector.
121 * The in control point is the length of the preceding segment back along this bisector multiplied by the curvature
122 * The out control point is the length of the succeeding segment forward along this bisector multiplied by the curvature
124 * @pre There are at least two points in the path ( one segment ).
126 * @param[in] curvature The curvature of the spline. 0 gives straight lines between the knots,
127 * negative values means the spline contains loops, positive values up to
128 * 0.5 result in a smooth curve, positive values between 0.5 and 1 result
129 * in looped curves where the loops are not distinct (i.e. the curve appears
130 * to be non-continuous), positive values higher than 1 result in looped curves.
132 void GenerateControlPoints( float curvature );
135 * @brief Sample path at a given progress. Calculates position and tangent at that point of the curve
137 * @param[in] progress A floating point value between 0.0 and 1.0.
138 * @param[out] position The interpolated position at that progress.
139 * @param[out] tangent The interpolated tangent at that progress.
141 void Sample( float progress, Vector3& position, Vector3& tangent ) const;
144 * @brief Accessor for the interpolation points.
146 * @param[in] index The index of the interpolation point.
147 * @return A reference to the interpolation point.
149 Vector3& GetPoint( size_t index );
152 * @brief Accessor for the control points.
154 * @param[in] index The index of the control point.
155 * @return A reference to the control point.
157 Vector3& GetControlPoint( size_t index );
160 * @brief Get the number of interpolation points in the path
162 * @return The number of interpolation points in the path
164 size_t GetPointCount() const;
166 public: // Not intended for application developers
168 * @brief This constructor is used by Dali::New() methods.
170 * @param[in] path A pointer to an internal path resource
172 explicit DALI_INTERNAL Path(Internal::Path* path);
177 #endif // __DALI_KEY_FRAMES_H__