zdoom-macos-deps/deps/sfml/include/SFML/Graphics/BlendMode.hpp
2021-06-23 10:16:33 +03:00

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////////////////////////////////////////////////////////////
//
// SFML - Simple and Fast Multimedia Library
// Copyright (C) 2007-2018 Laurent Gomila (laurent@sfml-dev.org)
//
// This software is provided 'as-is', without any express or implied warranty.
// In no event will the authors be held liable for any damages arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it freely,
// subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented;
// you must not claim that you wrote the original software.
// If you use this software in a product, an acknowledgment
// in the product documentation would be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such,
// and must not be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source distribution.
//
////////////////////////////////////////////////////////////
#ifndef SFML_BLENDMODE_HPP
#define SFML_BLENDMODE_HPP
////////////////////////////////////////////////////////////
// Headers
////////////////////////////////////////////////////////////
#include <SFML/Graphics/Export.hpp>
namespace sf
{
////////////////////////////////////////////////////////////
/// \brief Blending modes for drawing
///
////////////////////////////////////////////////////////////
struct SFML_GRAPHICS_API BlendMode
{
////////////////////////////////////////////////////////
/// \brief Enumeration of the blending factors
///
/// The factors are mapped directly to their OpenGL equivalents,
/// specified by glBlendFunc() or glBlendFuncSeparate().
////////////////////////////////////////////////////////
enum Factor
{
Zero, ///< (0, 0, 0, 0)
One, ///< (1, 1, 1, 1)
SrcColor, ///< (src.r, src.g, src.b, src.a)
OneMinusSrcColor, ///< (1, 1, 1, 1) - (src.r, src.g, src.b, src.a)
DstColor, ///< (dst.r, dst.g, dst.b, dst.a)
OneMinusDstColor, ///< (1, 1, 1, 1) - (dst.r, dst.g, dst.b, dst.a)
SrcAlpha, ///< (src.a, src.a, src.a, src.a)
OneMinusSrcAlpha, ///< (1, 1, 1, 1) - (src.a, src.a, src.a, src.a)
DstAlpha, ///< (dst.a, dst.a, dst.a, dst.a)
OneMinusDstAlpha ///< (1, 1, 1, 1) - (dst.a, dst.a, dst.a, dst.a)
};
////////////////////////////////////////////////////////
/// \brief Enumeration of the blending equations
///
/// The equations are mapped directly to their OpenGL equivalents,
/// specified by glBlendEquation() or glBlendEquationSeparate().
////////////////////////////////////////////////////////
enum Equation
{
Add, ///< Pixel = Src * SrcFactor + Dst * DstFactor
Subtract, ///< Pixel = Src * SrcFactor - Dst * DstFactor
ReverseSubtract ///< Pixel = Dst * DstFactor - Src * SrcFactor
};
////////////////////////////////////////////////////////////
/// \brief Default constructor
///
/// Constructs a blending mode that does alpha blending.
///
////////////////////////////////////////////////////////////
BlendMode();
////////////////////////////////////////////////////////////
/// \brief Construct the blend mode given the factors and equation.
///
/// This constructor uses the same factors and equation for both
/// color and alpha components. It also defaults to the Add equation.
///
/// \param sourceFactor Specifies how to compute the source factor for the color and alpha channels.
/// \param destinationFactor Specifies how to compute the destination factor for the color and alpha channels.
/// \param blendEquation Specifies how to combine the source and destination colors and alpha.
///
////////////////////////////////////////////////////////////
BlendMode(Factor sourceFactor, Factor destinationFactor, Equation blendEquation = Add);
////////////////////////////////////////////////////////////
/// \brief Construct the blend mode given the factors and equation.
///
/// \param colorSourceFactor Specifies how to compute the source factor for the color channels.
/// \param colorDestinationFactor Specifies how to compute the destination factor for the color channels.
/// \param colorBlendEquation Specifies how to combine the source and destination colors.
/// \param alphaSourceFactor Specifies how to compute the source factor.
/// \param alphaDestinationFactor Specifies how to compute the destination factor.
/// \param alphaBlendEquation Specifies how to combine the source and destination alphas.
///
////////////////////////////////////////////////////////////
BlendMode(Factor colorSourceFactor, Factor colorDestinationFactor,
Equation colorBlendEquation, Factor alphaSourceFactor,
Factor alphaDestinationFactor, Equation alphaBlendEquation);
////////////////////////////////////////////////////////////
// Member Data
////////////////////////////////////////////////////////////
Factor colorSrcFactor; ///< Source blending factor for the color channels
Factor colorDstFactor; ///< Destination blending factor for the color channels
Equation colorEquation; ///< Blending equation for the color channels
Factor alphaSrcFactor; ///< Source blending factor for the alpha channel
Factor alphaDstFactor; ///< Destination blending factor for the alpha channel
Equation alphaEquation; ///< Blending equation for the alpha channel
};
////////////////////////////////////////////////////////////
/// \relates BlendMode
/// \brief Overload of the == operator
///
/// \param left Left operand
/// \param right Right operand
///
/// \return True if blending modes are equal, false if they are different
///
////////////////////////////////////////////////////////////
SFML_GRAPHICS_API bool operator ==(const BlendMode& left, const BlendMode& right);
////////////////////////////////////////////////////////////
/// \relates BlendMode
/// \brief Overload of the != operator
///
/// \param left Left operand
/// \param right Right operand
///
/// \return True if blending modes are different, false if they are equal
///
////////////////////////////////////////////////////////////
SFML_GRAPHICS_API bool operator !=(const BlendMode& left, const BlendMode& right);
////////////////////////////////////////////////////////////
// Commonly used blending modes
////////////////////////////////////////////////////////////
SFML_GRAPHICS_API extern const BlendMode BlendAlpha; ///< Blend source and dest according to dest alpha
SFML_GRAPHICS_API extern const BlendMode BlendAdd; ///< Add source to dest
SFML_GRAPHICS_API extern const BlendMode BlendMultiply; ///< Multiply source and dest
SFML_GRAPHICS_API extern const BlendMode BlendNone; ///< Overwrite dest with source
} // namespace sf
#endif // SFML_BLENDMODE_HPP
////////////////////////////////////////////////////////////
/// \class sf::BlendMode
/// \ingroup graphics
///
/// sf::BlendMode is a class that represents a blend mode. A blend
/// mode determines how the colors of an object you draw are
/// mixed with the colors that are already in the buffer.
///
/// The class is composed of 6 components, each of which has its
/// own public member variable:
/// \li %Color Source Factor (@ref colorSrcFactor)
/// \li %Color Destination Factor (@ref colorDstFactor)
/// \li %Color Blend Equation (@ref colorEquation)
/// \li Alpha Source Factor (@ref alphaSrcFactor)
/// \li Alpha Destination Factor (@ref alphaDstFactor)
/// \li Alpha Blend Equation (@ref alphaEquation)
///
/// The source factor specifies how the pixel you are drawing contributes
/// to the final color. The destination factor specifies how the pixel
/// already drawn in the buffer contributes to the final color.
///
/// The color channels RGB (red, green, blue; simply referred to as
/// color) and A (alpha; the transparency) can be treated separately. This
/// separation can be useful for specific blend modes, but most often you
/// won't need it and will simply treat the color as a single unit.
///
/// The blend factors and equations correspond to their OpenGL equivalents.
/// In general, the color of the resulting pixel is calculated according
/// to the following formula (\a src is the color of the source pixel, \a dst
/// the color of the destination pixel, the other variables correspond to the
/// public members, with the equations being + or - operators):
/// \code
/// dst.rgb = colorSrcFactor * src.rgb (colorEquation) colorDstFactor * dst.rgb
/// dst.a = alphaSrcFactor * src.a (alphaEquation) alphaDstFactor * dst.a
/// \endcode
/// All factors and colors are represented as floating point numbers between
/// 0 and 1. Where necessary, the result is clamped to fit in that range.
///
/// The most common blending modes are defined as constants
/// in the sf namespace:
///
/// \code
/// sf::BlendMode alphaBlending = sf::BlendAlpha;
/// sf::BlendMode additiveBlending = sf::BlendAdd;
/// sf::BlendMode multiplicativeBlending = sf::BlendMultiply;
/// sf::BlendMode noBlending = sf::BlendNone;
/// \endcode
///
/// In SFML, a blend mode can be specified every time you draw a sf::Drawable
/// object to a render target. It is part of the sf::RenderStates compound
/// that is passed to the member function sf::RenderTarget::draw().
///
/// \see sf::RenderStates, sf::RenderTarget
///
////////////////////////////////////////////////////////////