McRogueFace/deps_linux/SFML/Graphics/Transformable.hpp

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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_TRANSFORMABLE_HPP
#define SFML_TRANSFORMABLE_HPP
////////////////////////////////////////////////////////////
// Headers
////////////////////////////////////////////////////////////
#include <SFML/Graphics/Export.hpp>
#include <SFML/Graphics/Transform.hpp>
namespace sf
{
////////////////////////////////////////////////////////////
/// \brief Decomposed transform defined by a position, a rotation and a scale
///
////////////////////////////////////////////////////////////
class SFML_GRAPHICS_API Transformable
{
public:
////////////////////////////////////////////////////////////
/// \brief Default constructor
///
////////////////////////////////////////////////////////////
Transformable();
////////////////////////////////////////////////////////////
/// \brief Virtual destructor
///
////////////////////////////////////////////////////////////
virtual ~Transformable();
////////////////////////////////////////////////////////////
/// \brief set the position of the object
///
/// This function completely overwrites the previous position.
/// See the move function to apply an offset based on the previous position instead.
/// The default position of a transformable object is (0, 0).
///
/// \param x X coordinate of the new position
/// \param y Y coordinate of the new position
///
/// \see move, getPosition
///
////////////////////////////////////////////////////////////
void setPosition(float x, float y);
////////////////////////////////////////////////////////////
/// \brief set the position of the object
///
/// This function completely overwrites the previous position.
/// See the move function to apply an offset based on the previous position instead.
/// The default position of a transformable object is (0, 0).
///
/// \param position New position
///
/// \see move, getPosition
///
////////////////////////////////////////////////////////////
void setPosition(const Vector2f& position);
////////////////////////////////////////////////////////////
/// \brief set the orientation of the object
///
/// This function completely overwrites the previous rotation.
/// See the rotate function to add an angle based on the previous rotation instead.
/// The default rotation of a transformable object is 0.
///
/// \param angle New rotation, in degrees
///
/// \see rotate, getRotation
///
////////////////////////////////////////////////////////////
void setRotation(float angle);
////////////////////////////////////////////////////////////
/// \brief set the scale factors of the object
///
/// This function completely overwrites the previous scale.
/// See the scale function to add a factor based on the previous scale instead.
/// The default scale of a transformable object is (1, 1).
///
/// \param factorX New horizontal scale factor
/// \param factorY New vertical scale factor
///
/// \see scale, getScale
///
////////////////////////////////////////////////////////////
void setScale(float factorX, float factorY);
////////////////////////////////////////////////////////////
/// \brief set the scale factors of the object
///
/// This function completely overwrites the previous scale.
/// See the scale function to add a factor based on the previous scale instead.
/// The default scale of a transformable object is (1, 1).
///
/// \param factors New scale factors
///
/// \see scale, getScale
///
////////////////////////////////////////////////////////////
void setScale(const Vector2f& factors);
////////////////////////////////////////////////////////////
/// \brief set the local origin of the object
///
/// The origin of an object defines the center point for
/// all transformations (position, scale, rotation).
/// The coordinates of this point must be relative to the
/// top-left corner of the object, and ignore all
/// transformations (position, scale, rotation).
/// The default origin of a transformable object is (0, 0).
///
/// \param x X coordinate of the new origin
/// \param y Y coordinate of the new origin
///
/// \see getOrigin
///
////////////////////////////////////////////////////////////
void setOrigin(float x, float y);
////////////////////////////////////////////////////////////
/// \brief set the local origin of the object
///
/// The origin of an object defines the center point for
/// all transformations (position, scale, rotation).
/// The coordinates of this point must be relative to the
/// top-left corner of the object, and ignore all
/// transformations (position, scale, rotation).
/// The default origin of a transformable object is (0, 0).
///
/// \param origin New origin
///
/// \see getOrigin
///
////////////////////////////////////////////////////////////
void setOrigin(const Vector2f& origin);
////////////////////////////////////////////////////////////
/// \brief get the position of the object
///
/// \return Current position
///
/// \see setPosition
///
////////////////////////////////////////////////////////////
const Vector2f& getPosition() const;
////////////////////////////////////////////////////////////
/// \brief get the orientation of the object
///
/// The rotation is always in the range [0, 360].
///
/// \return Current rotation, in degrees
///
/// \see setRotation
///
////////////////////////////////////////////////////////////
float getRotation() const;
////////////////////////////////////////////////////////////
/// \brief get the current scale of the object
///
/// \return Current scale factors
///
/// \see setScale
///
////////////////////////////////////////////////////////////
const Vector2f& getScale() const;
////////////////////////////////////////////////////////////
/// \brief get the local origin of the object
///
/// \return Current origin
///
/// \see setOrigin
///
////////////////////////////////////////////////////////////
const Vector2f& getOrigin() const;
////////////////////////////////////////////////////////////
/// \brief Move the object by a given offset
///
/// This function adds to the current position of the object,
/// unlike setPosition which overwrites it.
/// Thus, it is equivalent to the following code:
/// \code
/// sf::Vector2f pos = object.getPosition();
/// object.setPosition(pos.x + offsetX, pos.y + offsetY);
/// \endcode
///
/// \param offsetX X offset
/// \param offsetY Y offset
///
/// \see setPosition
///
////////////////////////////////////////////////////////////
void move(float offsetX, float offsetY);
////////////////////////////////////////////////////////////
/// \brief Move the object by a given offset
///
/// This function adds to the current position of the object,
/// unlike setPosition which overwrites it.
/// Thus, it is equivalent to the following code:
/// \code
/// object.setPosition(object.getPosition() + offset);
/// \endcode
///
/// \param offset Offset
///
/// \see setPosition
///
////////////////////////////////////////////////////////////
void move(const Vector2f& offset);
////////////////////////////////////////////////////////////
/// \brief Rotate the object
///
/// This function adds to the current rotation of the object,
/// unlike setRotation which overwrites it.
/// Thus, it is equivalent to the following code:
/// \code
/// object.setRotation(object.getRotation() + angle);
/// \endcode
///
/// \param angle Angle of rotation, in degrees
///
////////////////////////////////////////////////////////////
void rotate(float angle);
////////////////////////////////////////////////////////////
/// \brief Scale the object
///
/// This function multiplies the current scale of the object,
/// unlike setScale which overwrites it.
/// Thus, it is equivalent to the following code:
/// \code
/// sf::Vector2f scale = object.getScale();
/// object.setScale(scale.x * factorX, scale.y * factorY);
/// \endcode
///
/// \param factorX Horizontal scale factor
/// \param factorY Vertical scale factor
///
/// \see setScale
///
////////////////////////////////////////////////////////////
void scale(float factorX, float factorY);
////////////////////////////////////////////////////////////
/// \brief Scale the object
///
/// This function multiplies the current scale of the object,
/// unlike setScale which overwrites it.
/// Thus, it is equivalent to the following code:
/// \code
/// sf::Vector2f scale = object.getScale();
/// object.setScale(scale.x * factor.x, scale.y * factor.y);
/// \endcode
///
/// \param factor Scale factors
///
/// \see setScale
///
////////////////////////////////////////////////////////////
void scale(const Vector2f& factor);
////////////////////////////////////////////////////////////
/// \brief get the combined transform of the object
///
/// \return Transform combining the position/rotation/scale/origin of the object
///
/// \see getInverseTransform
///
////////////////////////////////////////////////////////////
const Transform& getTransform() const;
////////////////////////////////////////////////////////////
/// \brief get the inverse of the combined transform of the object
///
/// \return Inverse of the combined transformations applied to the object
///
/// \see getTransform
///
////////////////////////////////////////////////////////////
const Transform& getInverseTransform() const;
private:
////////////////////////////////////////////////////////////
// Member data
////////////////////////////////////////////////////////////
Vector2f m_origin; ///< Origin of translation/rotation/scaling of the object
Vector2f m_position; ///< Position of the object in the 2D world
float m_rotation; ///< Orientation of the object, in degrees
Vector2f m_scale; ///< Scale of the object
mutable Transform m_transform; ///< Combined transformation of the object
mutable bool m_transformNeedUpdate; ///< Does the transform need to be recomputed?
mutable Transform m_inverseTransform; ///< Combined transformation of the object
mutable bool m_inverseTransformNeedUpdate; ///< Does the transform need to be recomputed?
};
} // namespace sf
#endif // SFML_TRANSFORMABLE_HPP
////////////////////////////////////////////////////////////
/// \class sf::Transformable
/// \ingroup graphics
///
/// This class is provided for convenience, on top of sf::Transform.
///
/// sf::Transform, as a low-level class, offers a great level of
/// flexibility but it is not always convenient to manage. Indeed,
/// one can easily combine any kind of operation, such as a translation
/// followed by a rotation followed by a scaling, but once the result
/// transform is built, there's no way to go backward and, let's say,
/// change only the rotation without modifying the translation and scaling.
/// The entire transform must be recomputed, which means that you
/// need to retrieve the initial translation and scale factors as
/// well, and combine them the same way you did before updating the
/// rotation. This is a tedious operation, and it requires to store
/// all the individual components of the final transform.
///
/// That's exactly what sf::Transformable was written for: it hides
/// these variables and the composed transform behind an easy to use
/// interface. You can set or get any of the individual components
/// without worrying about the others. It also provides the composed
/// transform (as a sf::Transform), and keeps it up-to-date.
///
/// In addition to the position, rotation and scale, sf::Transformable
/// provides an "origin" component, which represents the local origin
/// of the three other components. Let's take an example with a 10x10
/// pixels sprite. By default, the sprite is positioned/rotated/scaled
/// relatively to its top-left corner, because it is the local point
/// (0, 0). But if we change the origin to be (5, 5), the sprite will
/// be positioned/rotated/scaled around its center instead. And if
/// we set the origin to (10, 10), it will be transformed around its
/// bottom-right corner.
///
/// To keep the sf::Transformable class simple, there's only one
/// origin for all the components. You cannot position the sprite
/// relatively to its top-left corner while rotating it around its
/// center, for example. To do such things, use sf::Transform directly.
///
/// sf::Transformable can be used as a base class. It is often
/// combined with sf::Drawable -- that's what SFML's sprites,
/// texts and shapes do.
/// \code
/// class MyEntity : public sf::Transformable, public sf::Drawable
/// {
/// virtual void draw(sf::RenderTarget& target, sf::RenderStates states) const
/// {
/// states.transform *= getTransform();
/// target.draw(..., states);
/// }
/// };
///
/// MyEntity entity;
/// entity.setPosition(10, 20);
/// entity.setRotation(45);
/// window.draw(entity);
/// \endcode
///
/// It can also be used as a member, if you don't want to use
/// its API directly (because you don't need all its functions,
/// or you have different naming conventions for example).
/// \code
/// class MyEntity
/// {
/// public:
/// void SetPosition(const MyVector& v)
/// {
/// myTransform.setPosition(v.x(), v.y());
/// }
///
/// void Draw(sf::RenderTarget& target) const
/// {
/// target.draw(..., myTransform.getTransform());
/// }
///
/// private:
/// sf::Transformable myTransform;
/// };
/// \endcode
///
/// A note on coordinates and undistorted rendering: \n
/// By default, SFML (or more exactly, OpenGL) may interpolate drawable objects
/// such as sprites or texts when rendering. While this allows transitions
/// like slow movements or rotations to appear smoothly, it can lead to
/// unwanted results in some cases, for example blurred or distorted objects.
/// In order to render a sf::Drawable object pixel-perfectly, make sure
/// the involved coordinates allow a 1:1 mapping of pixels in the window
/// to texels (pixels in the texture). More specifically, this means:
/// * The object's position, origin and scale have no fractional part
/// * The object's and the view's rotation are a multiple of 90 degrees
/// * The view's center and size have no fractional part
///
/// \see sf::Transform
///
////////////////////////////////////////////////////////////