1 #ifndef __DALI_TOOLKIT_INTERNAL_GRADIENT_H__
2 #define __DALI_TOOLKIT_INTERNAL_GRADIENT_H__
5 * Copyright (c) 2016 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/math/matrix3.h>
23 #include <dali/public-api/object/ref-object.h>
24 #include <dali/public-api/common/dali-vector.h>
25 #include <dali/public-api/images/buffer-image.h>
26 #include <dali/devel-api/rendering/texture.h>
40 * Gradients consist of continuously smooth color transitions along a vector from one color to another,
41 * possibly followed by additional transitions along the same vector to other colors.
43 class Gradient : public RefObject
47 * Defines the coordinate system of the attributes
48 * (start and end position for linear gradient, circle center and radius for radial gradient)
57 * Indicates what happens if the gradient starts or ends inside the bounds of the object being painted by the gradient.
61 PAD, // use the terminal colors of the gradient to fill the remainder of the target region
62 REPEAT, // reflect the gradient pattern start-to-end, end-to-start, start-to-end, etc. continuously until the target rectangle is filled
63 REFLECT // repeat the gradient pattern start-to-end, start-to-end, start-to-end, etc. continuously until the target region is filled
67 * The stop node tells the gradient what color it should be at certain position.
71 GradientStop( float offset, const Vector4& color )
72 : mOffset( offset ), mStopColor( color )
75 bool operator<(const GradientStop& rhs) const
77 return mOffset < rhs.mOffset;
80 float mOffset; // A value ranging from 0 to 1 to indicate where the gradient stop is placed.
81 Vector4 mStopColor; // The color to use at this gradient stop
87 * Add a gradient stop.
89 * @param[in] offset The position to place the stop.
90 * @param[in] color The color to use at this stop.
92 void AddStop(float offset, const Vector4& color);
95 * Get the gradient stops.
96 * @return The vector of gradient stops.
98 const Vector<GradientStop>& GetStops();
101 * Set the coordinate system used by the gradient attributes.
102 * @param[in] gradientUnits The the attributes are defined using the current user coordinate system or the bounding box of the shape.
104 void SetGradientUnits( GradientUnits gradientUnits );
107 * Get the coordinate system used by the gradient attributes.
108 * @return USER_SPACE_ON_USE or OBJECT_BOUNDING_BOX
110 GradientUnits GetGradientUnits() const;
113 * Indicates what happens if the gradient starts or ends inside the bounds of the target rectangle.
114 * If not specified, the effect is as if a value of 'pad' were specified
116 * @param[in] spread The method to fill the remainder of target region which is outside the gradient bounds
118 void SetSpreadMethod( SpreadMethod spread );
121 * Get the filling method for the the remainder of target region which is outside the gradient boun.
122 * @return PAD, REFLECT or REPEAT
124 SpreadMethod GetSpreadMethod() const;
127 * Get the transformation matrix to align the vertices with the gradient line/circle
128 * @ return the aligning transformation matrix
130 const Matrix3& GetAlignmentTransform() const;
133 * Generate the lookup texture with the gradient stops.
134 * @return The lookup texture which transit smoothly between stops.
136 Dali::Texture GenerateLookupTexture();
141 * Estimate the resolution of the lookup texture.
142 * Note: Only call this function after the gradient stops are sorted in order.
144 unsigned int EstimateTextureResolution();
149 * Construct a new Gradient object
150 * Called in the constructor of subclasses
155 * @brief A reference counted object may only be deleted by calling Unreference().
160 Gradient( const Gradient& gradient );
163 Gradient& operator=( const Gradient& handle );
167 Vector<GradientStop> mGradientStops;
168 Matrix3 mAlignmentTransform;
169 GradientUnits mGradientUnits;
170 SpreadMethod mSpreadMethod;
174 } // namespace Internal
176 } // namespace Toolkit
180 #endif /* __DALI_TOOLKIT_INTERNAL_GRADIENT_RENDERER_H__ */