| // Copyright 2013 The Flutter Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| import 'package:ui/ui.dart' as ui; |
| |
| import 'canvaskit/color_filter.dart'; |
| |
| /// A description of a color filter to apply when drawing a shape or compositing |
| /// a layer with a particular [Paint]. A color filter is a function that takes |
| /// two colors, and outputs one color. When applied during compositing, it is |
| /// independently applied to each pixel of the layer being drawn before the |
| /// entire layer is merged with the destination. |
| /// |
| /// Instances of this class are used with [Paint.colorFilter] on [Paint] |
| /// objects. |
| class EngineColorFilter implements ui.ColorFilter { |
| /// Creates a color filter that applies the blend mode given as the second |
| /// argument. The source color is the one given as the first argument, and the |
| /// destination color is the one from the layer being composited. |
| /// |
| /// The output of this filter is then composited into the background according |
| /// to the [Paint.blendMode], using the output of this filter as the source |
| /// and the background as the destination. |
| const factory EngineColorFilter.mode(ui.Color color, ui.BlendMode blendMode) = |
| CkBlendModeColorFilter; |
| |
| /// Construct a color filter that transforms a color by a 5x5 matrix, where |
| /// the fifth row is implicitly added in an identity configuration. |
| /// |
| /// Every pixel's color value, repsented as an `[R, G, B, A]`, is matrix |
| /// multiplied to create a new color: |
| /// |
| /// ```text |
| /// | R' | | a00 a01 a02 a03 a04 | | R | |
| /// | G' | | a10 a11 a22 a33 a44 | | G | |
| /// | B' | = | a20 a21 a22 a33 a44 | * | B | |
| /// | A' | | a30 a31 a22 a33 a44 | | A | |
| /// | 1 | | 0 0 0 0 1 | | 1 | |
| /// ``` |
| /// |
| /// The matrix is in row-major order and the translation column is specified |
| /// in unnormalized, 0...255, space. For example, the identity matrix is: |
| /// |
| /// ``` |
| /// const ColorMatrix identity = ColorFilter.matrix(<double>[ |
| /// 1, 0, 0, 0, 0, |
| /// 0, 1, 0, 0, 0, |
| /// 0, 0, 1, 0, 0, |
| /// 0, 0, 0, 1, 0, |
| /// ]); |
| /// ``` |
| /// |
| /// ## Examples |
| /// |
| /// An inversion color matrix: |
| /// |
| /// ``` |
| /// const ColorFilter invert = ColorFilter.matrix(<double>[ |
| /// -1, 0, 0, 0, 255, |
| /// 0, -1, 0, 0, 255, |
| /// 0, 0, -1, 0, 255, |
| /// 0, 0, 0, 1, 0, |
| /// ]); |
| /// ``` |
| /// |
| /// A sepia-toned color matrix (values based on the [Filter Effects Spec](https://www.w3.org/TR/filter-effects-1/#sepiaEquivalent)): |
| /// |
| /// ``` |
| /// const ColorFilter sepia = ColorFilter.matrix(<double>[ |
| /// 0.393, 0.769, 0.189, 0, 0, |
| /// 0.349, 0.686, 0.168, 0, 0, |
| /// 0.272, 0.534, 0.131, 0, 0, |
| /// 0, 0, 0, 1, 0, |
| /// ]); |
| /// ``` |
| /// |
| /// A greyscale color filter (values based on the [Filter Effects Spec](https://www.w3.org/TR/filter-effects-1/#grayscaleEquivalent)): |
| /// |
| /// ``` |
| /// const ColorFilter greyscale = ColorFilter.matrix(<double>[ |
| /// 0.2126, 0.7152, 0.0722, 0, 0, |
| /// 0.2126, 0.7152, 0.0722, 0, 0, |
| /// 0.2126, 0.7152, 0.0722, 0, 0, |
| /// 0, 0, 0, 1, 0, |
| /// ]); |
| /// ``` |
| const factory EngineColorFilter.matrix(List<double> matrix) = |
| CkMatrixColorFilter; |
| |
| /// Construct a color filter that applies the sRGB gamma curve to the RGB |
| /// channels. |
| const factory EngineColorFilter.linearToSrgbGamma() = |
| CkLinearToSrgbGammaColorFilter; |
| |
| /// Creates a color filter that applies the inverse of the sRGB gamma curve |
| /// to the RGB channels. |
| const factory EngineColorFilter.srgbToLinearGamma() = |
| CkSrgbToLinearGammaColorFilter; |
| } |