660 lines
25 KiB
C++
660 lines
25 KiB
C++
////////////////////////////////////////////////////////////
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//
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// SFML - Simple and Fast Multimedia Library
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// Copyright (C) 2007-2015 Laurent Gomila (laurent@sfml-dev.org)
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//
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// This software is provided 'as-is', without any express or implied warranty.
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// In no event will the authors be held liable for any damages arising from the use of this software.
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//
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// Permission is granted to anyone to use this software for any purpose,
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// including commercial applications, and to alter it and redistribute it freely,
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// subject to the following restrictions:
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//
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// 1. The origin of this software must not be misrepresented;
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// you must not claim that you wrote the original software.
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// If you use this software in a product, an acknowledgment
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// in the product documentation would be appreciated but is not required.
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//
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// 2. Altered source versions must be plainly marked as such,
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// and must not be misrepresented as being the original software.
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//
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// 3. This notice may not be removed or altered from any source distribution.
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//
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////////////////////////////////////////////////////////////
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#ifndef SFML_SHADER_HPP
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#define SFML_SHADER_HPP
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////////////////////////////////////////////////////////////
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// Headers
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////////////////////////////////////////////////////////////
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#include <SFML/Graphics/Export.hpp>
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#include <SFML/Graphics/Transform.hpp>
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#include <SFML/Graphics/Color.hpp>
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#include <SFML/Window/GlResource.hpp>
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#include <SFML/System/NonCopyable.hpp>
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#include <SFML/System/Vector2.hpp>
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#include <SFML/System/Vector3.hpp>
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#include <map>
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#include <string>
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namespace sf
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{
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class InputStream;
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class Texture;
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////////////////////////////////////////////////////////////
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/// \brief Shader class (vertex and fragment)
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///
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////////////////////////////////////////////////////////////
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class SFML_GRAPHICS_API Shader : GlResource, NonCopyable
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{
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public:
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////////////////////////////////////////////////////////////
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/// \brief Types of shaders
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///
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////////////////////////////////////////////////////////////
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enum Type
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{
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Vertex, ///< Vertex shader
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Fragment ///< Fragment (pixel) shader
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};
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////////////////////////////////////////////////////////////
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/// \brief Special type that can be passed to setParameter,
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/// and that represents the texture of the object being drawn
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///
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/// \see setParameter(const std::string&, CurrentTextureType)
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///
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////////////////////////////////////////////////////////////
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struct CurrentTextureType {};
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////////////////////////////////////////////////////////////
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/// \brief Represents the texture of the object being drawn
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///
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/// \see setParameter(const std::string&, CurrentTextureType)
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///
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////////////////////////////////////////////////////////////
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static CurrentTextureType CurrentTexture;
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public:
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////////////////////////////////////////////////////////////
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/// \brief Default constructor
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///
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/// This constructor creates an invalid shader.
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///
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////////////////////////////////////////////////////////////
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Shader();
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////////////////////////////////////////////////////////////
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/// \brief Destructor
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///
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////////////////////////////////////////////////////////////
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~Shader();
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////////////////////////////////////////////////////////////
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/// \brief Load either the vertex or fragment shader from a file
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///
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/// This function loads a single shader, either vertex or
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/// fragment, identified by the second argument.
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/// The source must be a text file containing a valid
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/// shader in GLSL language. GLSL is a C-like language
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/// dedicated to OpenGL shaders; you'll probably need to
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/// read a good documentation for it before writing your
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/// own shaders.
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///
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/// \param filename Path of the vertex or fragment shader file to load
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/// \param type Type of shader (vertex or fragment)
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///
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/// \return True if loading succeeded, false if it failed
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///
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/// \see loadFromMemory, loadFromStream
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///
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////////////////////////////////////////////////////////////
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bool loadFromFile(const std::string& filename, Type type);
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////////////////////////////////////////////////////////////
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/// \brief Load both the vertex and fragment shaders from files
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///
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/// This function loads both the vertex and the fragment
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/// shaders. If one of them fails to load, the shader is left
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/// empty (the valid shader is unloaded).
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/// The sources must be text files containing valid shaders
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/// in GLSL language. GLSL is a C-like language dedicated to
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/// OpenGL shaders; you'll probably need to read a good documentation
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/// for it before writing your own shaders.
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///
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/// \param vertexShaderFilename Path of the vertex shader file to load
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/// \param fragmentShaderFilename Path of the fragment shader file to load
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///
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/// \return True if loading succeeded, false if it failed
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///
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/// \see loadFromMemory, loadFromStream
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///
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////////////////////////////////////////////////////////////
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bool loadFromFile(const std::string& vertexShaderFilename, const std::string& fragmentShaderFilename);
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////////////////////////////////////////////////////////////
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/// \brief Load either the vertex or fragment shader from a source code in memory
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///
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/// This function loads a single shader, either vertex or
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/// fragment, identified by the second argument.
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/// The source code must be a valid shader in GLSL language.
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/// GLSL is a C-like language dedicated to OpenGL shaders;
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/// you'll probably need to read a good documentation for
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/// it before writing your own shaders.
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///
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/// \param shader String containing the source code of the shader
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/// \param type Type of shader (vertex or fragment)
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///
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/// \return True if loading succeeded, false if it failed
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///
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/// \see loadFromFile, loadFromStream
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///
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////////////////////////////////////////////////////////////
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bool loadFromMemory(const std::string& shader, Type type);
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////////////////////////////////////////////////////////////
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/// \brief Load both the vertex and fragment shaders from source codes in memory
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///
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/// This function loads both the vertex and the fragment
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/// shaders. If one of them fails to load, the shader is left
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/// empty (the valid shader is unloaded).
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/// The sources must be valid shaders in GLSL language. GLSL is
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/// a C-like language dedicated to OpenGL shaders; you'll
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/// probably need to read a good documentation for it before
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/// writing your own shaders.
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///
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/// \param vertexShader String containing the source code of the vertex shader
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/// \param fragmentShader String containing the source code of the fragment shader
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///
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/// \return True if loading succeeded, false if it failed
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///
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/// \see loadFromFile, loadFromStream
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///
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////////////////////////////////////////////////////////////
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bool loadFromMemory(const std::string& vertexShader, const std::string& fragmentShader);
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////////////////////////////////////////////////////////////
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/// \brief Load either the vertex or fragment shader from a custom stream
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///
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/// This function loads a single shader, either vertex or
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/// fragment, identified by the second argument.
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/// The source code must be a valid shader in GLSL language.
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/// GLSL is a C-like language dedicated to OpenGL shaders;
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/// you'll probably need to read a good documentation for it
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/// before writing your own shaders.
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///
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/// \param stream Source stream to read from
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/// \param type Type of shader (vertex or fragment)
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///
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/// \return True if loading succeeded, false if it failed
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///
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/// \see loadFromFile, loadFromMemory
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///
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////////////////////////////////////////////////////////////
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bool loadFromStream(InputStream& stream, Type type);
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////////////////////////////////////////////////////////////
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/// \brief Load both the vertex and fragment shaders from custom streams
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///
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/// This function loads both the vertex and the fragment
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/// shaders. If one of them fails to load, the shader is left
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/// empty (the valid shader is unloaded).
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/// The source codes must be valid shaders in GLSL language.
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/// GLSL is a C-like language dedicated to OpenGL shaders;
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/// you'll probably need to read a good documentation for
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/// it before writing your own shaders.
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///
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/// \param vertexShaderStream Source stream to read the vertex shader from
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/// \param fragmentShaderStream Source stream to read the fragment shader from
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///
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/// \return True if loading succeeded, false if it failed
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///
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/// \see loadFromFile, loadFromMemory
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///
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////////////////////////////////////////////////////////////
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bool loadFromStream(InputStream& vertexShaderStream, InputStream& fragmentShaderStream);
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////////////////////////////////////////////////////////////
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/// \brief Change a float parameter of the shader
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///
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/// \a name is the name of the variable to change in the shader.
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/// The corresponding parameter in the shader must be a float
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/// (float GLSL type).
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///
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/// Example:
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/// \code
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/// uniform float myparam; // this is the variable in the shader
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/// \endcode
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/// \code
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/// shader.setParameter("myparam", 5.2f);
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/// \endcode
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///
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/// \param name Name of the parameter in the shader
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/// \param x Value to assign
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///
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////////////////////////////////////////////////////////////
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void setParameter(const std::string& name, float x);
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////////////////////////////////////////////////////////////
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/// \brief Change a 2-components vector parameter of the shader
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///
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/// \a name is the name of the variable to change in the shader.
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/// The corresponding parameter in the shader must be a 2x1 vector
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/// (vec2 GLSL type).
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///
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/// Example:
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/// \code
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/// uniform vec2 myparam; // this is the variable in the shader
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/// \endcode
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/// \code
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/// shader.setParameter("myparam", 5.2f, 6.0f);
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/// \endcode
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///
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/// \param name Name of the parameter in the shader
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/// \param x First component of the value to assign
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/// \param y Second component of the value to assign
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///
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////////////////////////////////////////////////////////////
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void setParameter(const std::string& name, float x, float y);
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////////////////////////////////////////////////////////////
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/// \brief Change a 3-components vector parameter of the shader
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///
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/// \a name is the name of the variable to change in the shader.
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/// The corresponding parameter in the shader must be a 3x1 vector
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/// (vec3 GLSL type).
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///
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/// Example:
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/// \code
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/// uniform vec3 myparam; // this is the variable in the shader
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/// \endcode
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/// \code
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/// shader.setParameter("myparam", 5.2f, 6.0f, -8.1f);
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/// \endcode
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///
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/// \param name Name of the parameter in the shader
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/// \param x First component of the value to assign
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/// \param y Second component of the value to assign
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/// \param z Third component of the value to assign
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///
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////////////////////////////////////////////////////////////
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void setParameter(const std::string& name, float x, float y, float z);
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////////////////////////////////////////////////////////////
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/// \brief Change a 4-components vector parameter of the shader
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///
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/// \a name is the name of the variable to change in the shader.
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/// The corresponding parameter in the shader must be a 4x1 vector
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/// (vec4 GLSL type).
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///
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/// Example:
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/// \code
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/// uniform vec4 myparam; // this is the variable in the shader
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/// \endcode
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/// \code
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/// shader.setParameter("myparam", 5.2f, 6.0f, -8.1f, 0.4f);
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/// \endcode
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///
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/// \param name Name of the parameter in the shader
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/// \param x First component of the value to assign
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/// \param y Second component of the value to assign
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/// \param z Third component of the value to assign
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/// \param w Fourth component of the value to assign
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///
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////////////////////////////////////////////////////////////
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void setParameter(const std::string& name, float x, float y, float z, float w);
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////////////////////////////////////////////////////////////
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/// \brief Change a 2-components vector parameter of the shader
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///
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/// \a name is the name of the variable to change in the shader.
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/// The corresponding parameter in the shader must be a 2x1 vector
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/// (vec2 GLSL type).
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///
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/// Example:
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/// \code
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/// uniform vec2 myparam; // this is the variable in the shader
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/// \endcode
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/// \code
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/// shader.setParameter("myparam", sf::Vector2f(5.2f, 6.0f));
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/// \endcode
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///
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/// \param name Name of the parameter in the shader
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/// \param vector Vector to assign
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///
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////////////////////////////////////////////////////////////
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void setParameter(const std::string& name, const Vector2f& vector);
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////////////////////////////////////////////////////////////
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/// \brief Change a 3-components vector parameter of the shader
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///
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/// \a name is the name of the variable to change in the shader.
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/// The corresponding parameter in the shader must be a 3x1 vector
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/// (vec3 GLSL type).
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///
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/// Example:
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/// \code
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/// uniform vec3 myparam; // this is the variable in the shader
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/// \endcode
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/// \code
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/// shader.setParameter("myparam", sf::Vector3f(5.2f, 6.0f, -8.1f));
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/// \endcode
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///
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/// \param name Name of the parameter in the shader
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/// \param vector Vector to assign
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///
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////////////////////////////////////////////////////////////
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void setParameter(const std::string& name, const Vector3f& vector);
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////////////////////////////////////////////////////////////
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/// \brief Change a color parameter of the shader
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///
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/// \a name is the name of the variable to change in the shader.
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/// The corresponding parameter in the shader must be a 4x1 vector
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/// (vec4 GLSL type).
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///
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/// It is important to note that the components of the color are
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/// normalized before being passed to the shader. Therefore,
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/// they are converted from range [0 .. 255] to range [0 .. 1].
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/// For example, a sf::Color(255, 125, 0, 255) will be transformed
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/// to a vec4(1.0, 0.5, 0.0, 1.0) in the shader.
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///
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/// Example:
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/// \code
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/// uniform vec4 color; // this is the variable in the shader
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/// \endcode
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/// \code
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/// shader.setParameter("color", sf::Color(255, 128, 0, 255));
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/// \endcode
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///
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/// \param name Name of the parameter in the shader
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/// \param color Color to assign
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///
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////////////////////////////////////////////////////////////
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void setParameter(const std::string& name, const Color& color);
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////////////////////////////////////////////////////////////
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/// \brief Change a matrix parameter of the shader
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///
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/// \a name is the name of the variable to change in the shader.
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/// The corresponding parameter in the shader must be a 4x4 matrix
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/// (mat4 GLSL type).
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///
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/// Example:
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/// \code
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/// uniform mat4 matrix; // this is the variable in the shader
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/// \endcode
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/// \code
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/// sf::Transform transform;
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/// transform.translate(5, 10);
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/// shader.setParameter("matrix", transform);
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/// \endcode
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///
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/// \param name Name of the parameter in the shader
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/// \param transform Transform to assign
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///
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////////////////////////////////////////////////////////////
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void setParameter(const std::string& name, const Transform& transform);
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////////////////////////////////////////////////////////////
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/// \brief Change a texture parameter of the shader
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///
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/// \a name is the name of the variable to change in the shader.
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/// The corresponding parameter in the shader must be a 2D texture
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/// (sampler2D GLSL type).
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///
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/// Example:
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/// \code
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/// uniform sampler2D the_texture; // this is the variable in the shader
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/// \endcode
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/// \code
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/// sf::Texture texture;
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/// ...
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/// shader.setParameter("the_texture", texture);
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/// \endcode
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/// It is important to note that \a texture must remain alive as long
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/// as the shader uses it, no copy is made internally.
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///
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/// To use the texture of the object being draw, which cannot be
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/// known in advance, you can pass the special value
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/// sf::Shader::CurrentTexture:
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/// \code
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/// shader.setParameter("the_texture", sf::Shader::CurrentTexture).
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/// \endcode
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///
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/// \param name Name of the texture in the shader
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/// \param texture Texture to assign
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///
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////////////////////////////////////////////////////////////
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void setParameter(const std::string& name, const Texture& texture);
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////////////////////////////////////////////////////////////
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/// \brief Change a texture parameter of the shader
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///
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/// This overload maps a shader texture variable to the
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/// texture of the object being drawn, which cannot be
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/// known in advance. The second argument must be
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/// sf::Shader::CurrentTexture.
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/// The corresponding parameter in the shader must be a 2D texture
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/// (sampler2D GLSL type).
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///
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/// Example:
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/// \code
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/// uniform sampler2D current; // this is the variable in the shader
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/// \endcode
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/// \code
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/// shader.setParameter("current", sf::Shader::CurrentTexture);
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/// \endcode
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///
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/// \param name Name of the texture in the shader
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///
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////////////////////////////////////////////////////////////
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void setParameter(const std::string& name, CurrentTextureType);
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////////////////////////////////////////////////////////////
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/// \brief Get the underlying OpenGL handle of the shader.
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///
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/// You shouldn't need to use this function, unless you have
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/// very specific stuff to implement that SFML doesn't support,
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/// or implement a temporary workaround until a bug is fixed.
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///
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/// \return OpenGL handle of the shader or 0 if not yet loaded
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///
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////////////////////////////////////////////////////////////
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unsigned int getNativeHandle() const;
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////////////////////////////////////////////////////////////
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/// \brief Bind a shader for rendering
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///
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/// This function is not part of the graphics API, it mustn't be
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/// used when drawing SFML entities. It must be used only if you
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/// mix sf::Shader with OpenGL code.
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///
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/// \code
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/// sf::Shader s1, s2;
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/// ...
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/// sf::Shader::bind(&s1);
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/// // draw OpenGL stuff that use s1...
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/// sf::Shader::bind(&s2);
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/// // draw OpenGL stuff that use s2...
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/// sf::Shader::bind(NULL);
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/// // draw OpenGL stuff that use no shader...
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/// \endcode
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///
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/// \param shader Shader to bind, can be null to use no shader
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///
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////////////////////////////////////////////////////////////
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static void bind(const Shader* shader);
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////////////////////////////////////////////////////////////
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/// \brief Tell whether or not the system supports shaders
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///
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/// This function should always be called before using
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/// the shader features. If it returns false, then
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/// any attempt to use sf::Shader will fail.
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///
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/// Note: The first call to this function, whether by your
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/// code or SFML will result in a context switch.
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///
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/// \return True if shaders are supported, false otherwise
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///
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////////////////////////////////////////////////////////////
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static bool isAvailable();
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private:
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////////////////////////////////////////////////////////////
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/// \brief Compile the shader(s) and create the program
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///
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/// If one of the arguments is NULL, the corresponding shader
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/// is not created.
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///
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/// \param vertexShaderCode Source code of the vertex shader
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/// \param fragmentShaderCode Source code of the fragment shader
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///
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/// \return True on success, false if any error happened
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///
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////////////////////////////////////////////////////////////
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bool compile(const char* vertexShaderCode, const char* fragmentShaderCode);
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////////////////////////////////////////////////////////////
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/// \brief Bind all the textures used by the shader
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///
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/// This function each texture to a different unit, and
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/// updates the corresponding variables in the shader accordingly.
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///
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////////////////////////////////////////////////////////////
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void bindTextures() const;
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////////////////////////////////////////////////////////////
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/// \brief Get the location ID of a shader parameter
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///
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/// \param name Name of the parameter to search
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///
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/// \return Location ID of the parameter, or -1 if not found
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///
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////////////////////////////////////////////////////////////
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int getParamLocation(const std::string& name);
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////////////////////////////////////////////////////////////
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// Types
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////////////////////////////////////////////////////////////
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typedef std::map<int, const Texture*> TextureTable;
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typedef std::map<std::string, int> ParamTable;
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|
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////////////////////////////////////////////////////////////
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// Member data
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////////////////////////////////////////////////////////////
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unsigned int m_shaderProgram; ///< OpenGL identifier for the program
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int m_currentTexture; ///< Location of the current texture in the shader
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TextureTable m_textures; ///< Texture variables in the shader, mapped to their location
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ParamTable m_params; ///< Parameters location cache
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};
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} // namespace sf
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#endif // SFML_SHADER_HPP
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|
|
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////////////////////////////////////////////////////////////
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|
/// \class sf::Shader
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|
/// \ingroup graphics
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|
///
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|
/// Shaders are programs written using a specific language,
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|
/// executed directly by the graphics card and allowing
|
|
/// to apply real-time operations to the rendered entities.
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|
///
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|
/// There are two kinds of shaders:
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|
/// \li Vertex shaders, that process vertices
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|
/// \li Fragment (pixel) shaders, that process pixels
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|
///
|
|
/// A sf::Shader can be composed of either a vertex shader
|
|
/// alone, a fragment shader alone, or both combined
|
|
/// (see the variants of the load functions).
|
|
///
|
|
/// Shaders are written in GLSL, which is a C-like
|
|
/// language dedicated to OpenGL shaders. You'll probably
|
|
/// need to learn its basics before writing your own shaders
|
|
/// for SFML.
|
|
///
|
|
/// Like any C/C++ program, a shader has its own variables
|
|
/// that you can set from your C++ application. sf::Shader
|
|
/// handles 5 different types of variables:
|
|
/// \li floats
|
|
/// \li vectors (2, 3 or 4 components)
|
|
/// \li colors
|
|
/// \li textures
|
|
/// \li transforms (matrices)
|
|
///
|
|
/// The value of the variables can be changed at any time
|
|
/// with the various overloads of the setParameter function:
|
|
/// \code
|
|
/// shader.setParameter("offset", 2.f);
|
|
/// shader.setParameter("point", 0.5f, 0.8f, 0.3f);
|
|
/// shader.setParameter("color", sf::Color(128, 50, 255));
|
|
/// shader.setParameter("matrix", transform); // transform is a sf::Transform
|
|
/// shader.setParameter("overlay", texture); // texture is a sf::Texture
|
|
/// shader.setParameter("texture", sf::Shader::CurrentTexture);
|
|
/// \endcode
|
|
///
|
|
/// The special Shader::CurrentTexture argument maps the
|
|
/// given texture variable to the current texture of the
|
|
/// object being drawn (which cannot be known in advance).
|
|
///
|
|
/// To apply a shader to a drawable, you must pass it as an
|
|
/// additional parameter to the Draw function:
|
|
/// \code
|
|
/// window.draw(sprite, &shader);
|
|
/// \endcode
|
|
///
|
|
/// ... which is in fact just a shortcut for this:
|
|
/// \code
|
|
/// sf::RenderStates states;
|
|
/// states.shader = &shader;
|
|
/// window.draw(sprite, states);
|
|
/// \endcode
|
|
///
|
|
/// In the code above we pass a pointer to the shader, because it may
|
|
/// be null (which means "no shader").
|
|
///
|
|
/// Shaders can be used on any drawable, but some combinations are
|
|
/// not interesting. For example, using a vertex shader on a sf::Sprite
|
|
/// is limited because there are only 4 vertices, the sprite would
|
|
/// have to be subdivided in order to apply wave effects.
|
|
/// Another bad example is a fragment shader with sf::Text: the texture
|
|
/// of the text is not the actual text that you see on screen, it is
|
|
/// a big texture containing all the characters of the font in an
|
|
/// arbitrary order; thus, texture lookups on pixels other than the
|
|
/// current one may not give you the expected result.
|
|
///
|
|
/// Shaders can also be used to apply global post-effects to the
|
|
/// current contents of the target (like the old sf::PostFx class
|
|
/// in SFML 1). This can be done in two different ways:
|
|
/// \li draw everything to a sf::RenderTexture, then draw it to
|
|
/// the main target using the shader
|
|
/// \li draw everything directly to the main target, then use
|
|
/// sf::Texture::update(Window&) to copy its contents to a texture
|
|
/// and draw it to the main target using the shader
|
|
///
|
|
/// The first technique is more optimized because it doesn't involve
|
|
/// retrieving the target's pixels to system memory, but the
|
|
/// second one doesn't impact the rendering process and can be
|
|
/// easily inserted anywhere without impacting all the code.
|
|
///
|
|
/// Like sf::Texture that can be used as a raw OpenGL texture,
|
|
/// sf::Shader can also be used directly as a raw shader for
|
|
/// custom OpenGL geometry.
|
|
/// \code
|
|
/// sf::Shader::bind(&shader);
|
|
/// ... render OpenGL geometry ...
|
|
/// sf::Shader::bind(NULL);
|
|
/// \endcode
|
|
///
|
|
////////////////////////////////////////////////////////////
|