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/common/dali-vector.h>
23 #include <dali/public-api/images/buffer-image.h>
24 #include <dali/public-api/math/matrix3.h>
25 #include <dali/public-api/object/ref-object.h>
26 #include <dali/public-api/rendering/texture.h>
29 #include <dali-toolkit/public-api/visuals/gradient-visual-properties.h>
43 * Gradients consist of continuously smooth color transitions along a vector from one color to another,
44 * possibly followed by additional transitions along the same vector to other colors.
46 class Gradient : public RefObject
51 * The stop node tells the gradient what color it should be at certain position.
55 GradientStop( float offset, const Vector4& color )
56 : mOffset( offset ), mStopColor( color )
59 bool operator<(const GradientStop& rhs) const
61 return mOffset < rhs.mOffset;
64 float mOffset; // A value ranging from 0 to 1 to indicate where the gradient stop is placed.
65 Vector4 mStopColor; // The color to use at this gradient stop
71 * Add a gradient stop.
73 * @param[in] offset The position to place the stop.
74 * @param[in] color The color to use at this stop.
76 void AddStop(float offset, const Vector4& color);
79 * Get the gradient stops.
80 * @return The vector of gradient stops.
82 const Vector<GradientStop>& GetStops();
85 * Set the coordinate system used by the gradient attributes.
86 * @param[in] gradientUnits The the attributes are defined using the current user coordinate system or the bounding box of the shape.
88 void SetGradientUnits( Toolkit::GradientVisual::Units::Type gradientUnits );
91 * Get the coordinate system used by the gradient attributes.
92 * @return USER_SPACE_ON_USE or OBJECT_BOUNDING_BOX
94 Toolkit::GradientVisual::Units::Type GetGradientUnits() const;
97 * Indicates what happens if the gradient starts or ends inside the bounds of the target rectangle.
98 * If not specified, the effect is as if a value of 'pad' were specified
100 * @param[in] spread The method to fill the remainder of target region which is outside the gradient bounds
102 void SetSpreadMethod( Toolkit::GradientVisual::SpreadMethod::Type spread );
105 * Get the filling method for the the remainder of target region which is outside the gradient boun.
106 * @return PAD, REFLECT or REPEAT
108 Toolkit::GradientVisual::SpreadMethod::Type GetSpreadMethod() const;
111 * Get the transformation matrix to align the vertices with the gradient line/circle
112 * @ return the aligning transformation matrix
114 const Matrix3& GetAlignmentTransform() const;
117 * Generate the lookup texture with the gradient stops.
118 * @return The lookup texture which transit smoothly between stops.
120 Dali::Texture GenerateLookupTexture();
125 * Estimate the resolution of the lookup texture.
126 * Note: Only call this function after the gradient stops are sorted in order.
128 unsigned int EstimateTextureResolution();
133 * Construct a new Gradient object
134 * Called in the constructor of subclasses
139 * @brief A reference counted object may only be deleted by calling Unreference().
144 Gradient( const Gradient& gradient );
147 Gradient& operator=( const Gradient& handle );
151 Vector<GradientStop> mGradientStops;
152 Matrix3 mAlignmentTransform;
153 Toolkit::GradientVisual::Units::Type mGradientUnits;
154 Toolkit::GradientVisual::SpreadMethod::Type mSpreadMethod;
158 } // namespace Internal
160 } // namespace Toolkit
164 #endif // DALI_TOOLKIT_INTERNAL_GRADIENT_RENDERER_H