imgui-sfml-premake/sfml/include/SFML/Graphics/View.hpp

358 lines
14 KiB
C++

////////////////////////////////////////////////////////////
//
// SFML - Simple and Fast Multimedia Library
// Copyright (C) 2007-2025 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.
//
////////////////////////////////////////////////////////////
#pragma once
////////////////////////////////////////////////////////////
// Headers
////////////////////////////////////////////////////////////
#include <SFML/Graphics/Export.hpp>
#include <SFML/Graphics/Rect.hpp>
#include <SFML/Graphics/Transform.hpp>
#include <SFML/System/Angle.hpp>
#include <SFML/System/Vector2.hpp>
namespace sf
{
////////////////////////////////////////////////////////////
/// \brief 2D camera that defines what region is shown on screen
///
////////////////////////////////////////////////////////////
class SFML_GRAPHICS_API View
{
public:
////////////////////////////////////////////////////////////
/// \brief Default constructor
///
/// This constructor creates a default view of (0, 0, 1000, 1000)
///
////////////////////////////////////////////////////////////
View() = default;
////////////////////////////////////////////////////////////
/// \brief Construct the view from a rectangle
///
/// \param rectangle Rectangle defining the zone to display
///
////////////////////////////////////////////////////////////
explicit View(const FloatRect& rectangle);
////////////////////////////////////////////////////////////
/// \brief Construct the view from its center and size
///
/// \param center Center of the zone to display
/// \param size Size of zone to display
///
////////////////////////////////////////////////////////////
View(Vector2f center, Vector2f size);
////////////////////////////////////////////////////////////
/// \brief Set the center of the view
///
/// \param center New center
///
/// \see `setSize`, `getCenter`
///
////////////////////////////////////////////////////////////
void setCenter(Vector2f center);
////////////////////////////////////////////////////////////
/// \brief Set the size of the view
///
/// \param size New size
///
/// \see `setCenter`, `getCenter`
///
////////////////////////////////////////////////////////////
void setSize(Vector2f size);
////////////////////////////////////////////////////////////
/// \brief Set the orientation of the view
///
/// The default rotation of a view is 0 degree.
///
/// \param angle New angle
///
/// \see `getRotation`
///
////////////////////////////////////////////////////////////
void setRotation(Angle angle);
////////////////////////////////////////////////////////////
/// \brief Set the target viewport
///
/// The viewport is the rectangle into which the contents of the
/// view are displayed, expressed as a factor (between 0 and 1)
/// of the size of the RenderTarget to which the view is applied.
/// For example, a view which takes the left side of the target would
/// be defined with `view.setViewport(sf::FloatRect({0.f, 0.f}, {0.5f, 1.f}))`.
/// By default, a view has a viewport which covers the entire target.
///
/// \param viewport New viewport rectangle
///
/// \see `getViewport`
///
////////////////////////////////////////////////////////////
void setViewport(const FloatRect& viewport);
////////////////////////////////////////////////////////////
/// \brief Set the target scissor rectangle
///
/// The scissor rectangle, expressed as a factor (between 0 and 1) of
/// the RenderTarget, specifies the region of the RenderTarget whose
/// pixels are able to be modified by draw or clear operations.
/// Any pixels which lie outside of the scissor rectangle will
/// not be modified by draw or clear operations.
/// For example, a scissor rectangle which only allows modifications
/// to the right side of the target would be defined
/// with `view.setScissor(sf::FloatRect({0.5f, 0.f}, {0.5f, 1.f}))`.
/// By default, a view has a scissor rectangle which allows
/// modifications to the entire target. This is equivalent to
/// disabling the scissor test entirely. Passing the default
/// scissor rectangle to this function will also disable
/// scissor testing.
///
/// \param scissor New scissor rectangle
///
/// \see `getScissor`
///
////////////////////////////////////////////////////////////
void setScissor(const FloatRect& scissor);
////////////////////////////////////////////////////////////
/// \brief Get the center of the view
///
/// \return Center of the view
///
/// \see `getSize`, `setCenter`
///
////////////////////////////////////////////////////////////
[[nodiscard]] Vector2f getCenter() const;
////////////////////////////////////////////////////////////
/// \brief Get the size of the view
///
/// \return Size of the view
///
/// \see `getCenter`, `setSize`
///
////////////////////////////////////////////////////////////
[[nodiscard]] Vector2f getSize() const;
////////////////////////////////////////////////////////////
/// \brief Get the current orientation of the view
///
/// \return Rotation angle of the view
///
/// \see `setRotation`
///
////////////////////////////////////////////////////////////
[[nodiscard]] Angle getRotation() const;
////////////////////////////////////////////////////////////
/// \brief Get the target viewport rectangle of the view
///
/// \return Viewport rectangle, expressed as a factor of the target size
///
/// \see `setViewport`
///
////////////////////////////////////////////////////////////
[[nodiscard]] const FloatRect& getViewport() const;
////////////////////////////////////////////////////////////
/// \brief Get the scissor rectangle of the view
///
/// \return Scissor rectangle, expressed as a factor of the target size
///
/// \see `setScissor`
///
////////////////////////////////////////////////////////////
[[nodiscard]] const FloatRect& getScissor() const;
////////////////////////////////////////////////////////////
/// \brief Move the view relative to its current position
///
/// \param offset Move offset
///
/// \see `setCenter`, `rotate`, `zoom`
///
////////////////////////////////////////////////////////////
void move(Vector2f offset);
////////////////////////////////////////////////////////////
/// \brief Rotate the view relative to its current orientation
///
/// \param angle Angle to rotate
///
/// \see `setRotation`, `move`, `zoom`
///
////////////////////////////////////////////////////////////
void rotate(Angle angle);
////////////////////////////////////////////////////////////
/// \brief Resize the view rectangle relative to its current size
///
/// Resizing the view simulates a zoom, as the zone displayed on
/// screen grows or shrinks.
/// \a factor is a multiplier:
/// \li 1 keeps the size unchanged
/// \li > 1 makes the view bigger (objects appear smaller)
/// \li < 1 makes the view smaller (objects appear bigger)
///
/// \param factor Zoom factor to apply
///
/// \see `setSize`, `move`, `rotate`
///
////////////////////////////////////////////////////////////
void zoom(float factor);
////////////////////////////////////////////////////////////
/// \brief Get the projection transform of the view
///
/// This function is meant for internal use only.
///
/// \return Projection transform defining the view
///
/// \see `getInverseTransform`
///
////////////////////////////////////////////////////////////
[[nodiscard]] const Transform& getTransform() const;
////////////////////////////////////////////////////////////
/// \brief Get the inverse projection transform of the view
///
/// This function is meant for internal use only.
///
/// \return Inverse of the projection transform defining the view
///
/// \see `getTransform`
///
////////////////////////////////////////////////////////////
[[nodiscard]] const Transform& getInverseTransform() const;
private:
////////////////////////////////////////////////////////////
// Member data
////////////////////////////////////////////////////////////
Vector2f m_center{500, 500}; //!< Center of the view, in scene coordinates
Vector2f m_size{1000, 1000}; //!< Size of the view, in scene coordinates
Angle m_rotation; //!< Angle of rotation of the view rectangle
FloatRect m_viewport{{0, 0}, {1, 1}}; //!< Viewport rectangle, expressed as a factor of the render-target's size
FloatRect m_scissor{{0, 0}, {1, 1}}; //!< Scissor rectangle, expressed as a factor of the render-target's size
mutable Transform m_transform; //!< Precomputed projection transform corresponding to the view
mutable Transform m_inverseTransform; //!< Precomputed inverse projection transform corresponding to the view
mutable bool m_transformUpdated{}; //!< Internal state telling if the transform needs to be updated
mutable bool m_invTransformUpdated{}; //!< Internal state telling if the inverse transform needs to be updated
};
} // namespace sf
////////////////////////////////////////////////////////////
/// \class sf::View
/// \ingroup graphics
///
/// `sf::View` defines a camera in the 2D scene. This is a
/// very powerful concept: you can scroll, rotate or zoom
/// the entire scene without altering the way that your
/// drawable objects are drawn.
///
/// A view is composed of a source rectangle, which defines
/// what part of the 2D scene is shown, and a target viewport,
/// which defines where the contents of the source rectangle
/// will be displayed on the render target (window or texture).
///
/// The viewport allows to map the scene to a custom part
/// of the render target, and can be used for split-screen
/// or for displaying a minimap, for example. If the source
/// rectangle doesn't have the same size as the viewport, its
/// contents will be stretched to fit in.
///
/// The scissor rectangle allows for specifying regions of the
/// render target to which modifications can be made by draw
/// and clear operations. Only pixels that are within the region
/// will be able to be modified. Pixels outside of the region will
/// not be modified by draw or clear operations.
///
/// Certain effects can be created by either using the viewport or
/// scissor rectangle. While the results appear identical, there
/// can be times where one method should be preferred over the other.
/// Viewport transformations are applied during the vertex processing
/// stage of the graphics pipeline, before the primitives are
/// rasterized into fragments for fragment processing. Since
/// viewport processing has to be performed and cannot be disabled,
/// effects that are performed using the viewport transform are
/// basically free performance-wise. Scissor testing is performed in
/// the per-sample processing stage of the graphics pipeline, after
/// fragment processing has been performed. Because per-sample
/// processing is performed at the last stage of the pipeline,
/// fragments that are discarded at this stage will cause the
/// highest waste of GPU resources compared to any method that
/// would have discarded vertices or fragments earlier in the
/// pipeline. There are situations in which scissor testing has
/// to be used to control whether fragments are discarded or not.
/// An example of such a situation is when performing the viewport
/// transform on vertices is necessary but a subset of the generated
/// fragments should not have an effect on the stencil buffer or
/// blend with the color buffer.
//
/// To apply a view, you have to assign it to the render target.
/// Then, objects drawn in this render target will be
/// affected by the view until you use another view.
///
/// Usage example:
/// \code
/// sf::RenderWindow window;
///
/// // Initialize the view to a rectangle located at (100, 100) and with a size of 400x200
/// sf::View view(sf::FloatRect({100, 100}, {400, 200}));
///
/// // Rotate it by 45 degrees
/// view.rotate(sf::degrees(45));
///
/// // Set its target viewport to be half of the window
/// view.setViewport(sf::FloatRect({0.f, 0.f}, {0.5f, 1.f}));
///
/// // Apply it
/// window.setView(view);
///
/// // Render stuff
/// window.draw(someSprite);
///
/// // Set the default view back
/// window.setView(window.getDefaultView());
///
/// // Render stuff not affected by the view
/// window.draw(someText);
/// \endcode
///
/// See also the note on coordinates and undistorted rendering in `sf::Transformable`.
///
/// \see `sf::RenderWindow`, `sf::RenderTexture`
///
////////////////////////////////////////////////////////////