Target for off-screen 2D rendering into a texture. More...

#include <SFML/Graphics/RenderTexture.hpp>

Inheritance diagram for sf::RenderTexture:

Public Member Functions
	RenderTexture ()
	Default constructor.

	RenderTexture (Vector2u size, const ContextSettings &settings={})
	Construct a render-texture.

	~RenderTexture () override
	Destructor.

	RenderTexture (const RenderTexture &)=delete
	Deleted copy constructor.

RenderTexture &	operator= (const RenderTexture &)=delete
	Deleted copy assignment.

	RenderTexture (RenderTexture &&) noexcept
	Move constructor.

RenderTexture &	operator= (RenderTexture &&) noexcept
	Move assignment operator.

bool	resize (Vector2u size, const ContextSettings &settings={})
	Resize the render-texture.

void	setSmooth (bool smooth)
	Enable or disable texture smoothing.

bool	isSmooth () const
	Tell whether the smooth filtering is enabled or not.

void	setRepeated (bool repeated)
	Enable or disable texture repeating.

bool	isRepeated () const
	Tell whether the texture is repeated or not.

bool	generateMipmap ()
	Generate a mipmap using the current texture data.

bool	setActive (bool active=true) override
	Activate or deactivate the render-texture for rendering.

void	display ()
	Update the contents of the target texture.

Vector2u	getSize () const override
	Return the size of the rendering region of the texture.

bool	isSrgb () const override
	Tell if the render-texture will use sRGB encoding when drawing on it.

const Texture &	getTexture () const
	Get a read-only reference to the target texture.

void	clear (Color color=Color::Black)
	Clear the entire target with a single color.

void	clear (Color color, StencilValue stencilValue)
	Clear the entire target with a single color and stencil value.

void	clearStencil (StencilValue stencilValue)
	Clear the stencil buffer to a specific value.

void	setView (const View &view)
	Change the current active view.

const View &	getView () const
	Get the view currently in use in the render target.

const View &	getDefaultView () const
	Get the default view of the render target.

IntRect	getViewport (const View &view) const
	Get the viewport of a view, applied to this render target.

IntRect	getScissor (const View &view) const
	Get the scissor rectangle of a view, applied to this render target.

Vector2f	mapPixelToCoords (Vector2i point) const
	Convert a point from target coordinates to world coordinates, using the current view.

Vector2f	mapPixelToCoords (Vector2i point, const View &view) const
	Convert a point from target coordinates to world coordinates.

Vector2i	mapCoordsToPixel (Vector2f point) const
	Convert a point from world coordinates to target coordinates, using the current view.

Vector2i	mapCoordsToPixel (Vector2f point, const View &view) const
	Convert a point from world coordinates to target coordinates.

void	draw (const Drawable &drawable, const RenderStates &states=RenderStates::Default)
	Draw a drawable object to the render target.

void	draw (const Vertex *vertices, std::size_t vertexCount, PrimitiveType type, const RenderStates &states=RenderStates::Default)
	Draw primitives defined by an array of vertices.

void	draw (const VertexBuffer &vertexBuffer, const RenderStates &states=RenderStates::Default)
	Draw primitives defined by a vertex buffer.

void	draw (const VertexBuffer &vertexBuffer, std::size_t firstVertex, std::size_t vertexCount, const RenderStates &states=RenderStates::Default)
	Draw primitives defined by a vertex buffer.

void	pushGLStates ()
	Save the current OpenGL render states and matrices.

void	popGLStates ()
	Restore the previously saved OpenGL render states and matrices.

void	resetGLStates ()
	Reset the internal OpenGL states so that the target is ready for drawing.

Static Public Member Functions
static unsigned int	getMaximumAntiAliasingLevel ()
	Get the maximum anti-aliasing level supported by the system.

Protected Member Functions
void	initialize ()
	Performs the common initialization step after creation.

Detailed Description

Target for off-screen 2D rendering into a texture.

sf::RenderTexture is the little brother of sf::RenderWindow.

It implements the same 2D drawing and OpenGL-related functions (see their base class sf::RenderTarget for more details), the difference is that the result is stored in an off-screen texture rather than being show in a window.

Rendering to a texture can be useful in a variety of situations:

precomputing a complex static texture (like a level's background from multiple tiles)
applying post-effects to the whole scene with shaders
creating a sprite from a 3D object rendered with OpenGL
etc.

Usage example:

// Create a new render-window
sf::RenderWindow window(sf::VideoMode({800, 600}), "SFML window");
 
// Create a new render-texture
sf::RenderTexture texture({500, 500});
 
// The main loop
while (window.isOpen())
{
   // Event processing
   // ...
 
   // Clear the whole texture with red color
   texture.clear(sf::Color::Red);
 
   // Draw stuff to the texture
   texture.draw(sprite);  // sprite is a sf::Sprite
   texture.draw(shape);   // shape is a sf::Shape
   texture.draw(text);    // text is a sf::Text
 
   // We're done drawing to the texture
   texture.display();
 
   // Now we start rendering to the window, clear it first
   window.clear();
 
   // Draw the texture
   sf::Sprite sprite(texture.getTexture());
   window.draw(sprite);
 
   // End the current frame and display its contents on screen
   window.display();
}

Like sf::RenderWindow, sf::RenderTexture is still able to render direct OpenGL stuff. It is even possible to mix together OpenGL calls and regular SFML drawing commands. If you need a depth buffer for 3D rendering, don't forget to request it when calling RenderTexture::create.

See also: sf::RenderTarget, sf::RenderWindow, sf::View, sf::Texture

Definition at line 53 of file RenderTexture.hpp.

Constructor & Destructor Documentation

◆ RenderTexture() [1/4]

sf::RenderTexture::RenderTexture ( )

Default constructor.

Constructs a render-texture with width 0 and height 0.

See also: resize

◆ RenderTexture() [2/4]

sf::RenderTexture::RenderTexture	(	Vector2u	size,
		const ContextSettings &	settings = {} )

Construct a render-texture.

The last parameter, settings, is useful if you want to enable multi-sampling or use the render-texture for OpenGL rendering that requires a depth or stencil buffer. Otherwise it is unnecessary, and you should leave this parameter at its default value.

After creation, the contents of the render-texture are undefined. Call RenderTexture::clear first to ensure a single color fill.

Parameters

size	Width and height of the render-texture
settings	Additional settings for the underlying OpenGL texture and context

Exceptions

sf::Exception if creation was unsuccessful

◆ ~RenderTexture()

sf::RenderTexture::~RenderTexture ( )

override

Destructor.

◆ RenderTexture() [3/4]

sf::RenderTexture::RenderTexture ( const RenderTexture & )

delete

Deleted copy constructor.

◆ RenderTexture() [4/4]

sf::RenderTexture::RenderTexture ( RenderTexture && )

noexcept

Move constructor.

Member Function Documentation

◆ clear() [1/2]

void sf::RenderTarget::clear	(	Color	color,
		StencilValue	stencilValue )

inherited

Clear the entire target with a single color and stencil value.

The specified stencil value is truncated to the bit width of the current stencil buffer.

Parameters

color	Fill color to use to clear the render target
stencilValue	Stencil value to clear to

◆ clear() [2/2]

void sf::RenderTarget::clear ( Color color = Color::Black )

inherited

Clear the entire target with a single color.

This function is usually called once every frame, to clear the previous contents of the target.

Parameters

color Fill color to use to clear the render target

◆ clearStencil()

void sf::RenderTarget::clearStencil ( StencilValue stencilValue )

inherited

Clear the stencil buffer to a specific value.

The specified value is truncated to the bit width of the current stencil buffer.

Parameters

stencilValue Stencil value to clear to

◆ display()

void sf::RenderTexture::display ( )

Update the contents of the target texture.

This function updates the target texture with what has been drawn so far. Like for windows, calling this function is mandatory at the end of rendering. Not calling it may leave the texture in an undefined state.

◆ draw() [1/4]

void sf::RenderTarget::draw	(	const Drawable &	drawable,
		const RenderStates &	states = RenderStates::Default )

inherited

Draw a drawable object to the render target.

Parameters

drawable	Object to draw
states	Render states to use for drawing

◆ draw() [2/4]

void sf::RenderTarget::draw	(	const Vertex *	vertices,
		std::size_t	vertexCount,
		PrimitiveType	type,
		const RenderStates &	states = RenderStates::Default )

inherited

Draw primitives defined by an array of vertices.

Parameters

vertices	Pointer to the vertices
vertexCount	Number of vertices in the array
type	Type of primitives to draw
states	Render states to use for drawing

◆ draw() [3/4]

void sf::RenderTarget::draw	(	const VertexBuffer &	vertexBuffer,
		const RenderStates &	states = RenderStates::Default )

inherited

Draw primitives defined by a vertex buffer.

Parameters

vertexBuffer	Vertex buffer
states	Render states to use for drawing

◆ draw() [4/4]

void sf::RenderTarget::draw	(	const VertexBuffer &	vertexBuffer,
		std::size_t	firstVertex,
		std::size_t	vertexCount,
		const RenderStates &	states = RenderStates::Default )

inherited

Draw primitives defined by a vertex buffer.

Parameters

vertexBuffer	Vertex buffer
firstVertex	Index of the first vertex to render
vertexCount	Number of vertices to render
states	Render states to use for drawing

◆ generateMipmap()

bool sf::RenderTexture::generateMipmap ( )

nodiscard

Generate a mipmap using the current texture data.

This function is similar to Texture::generateMipmap and operates on the texture used as the target for drawing. Be aware that any draw operation may modify the base level image data. For this reason, calling this function only makes sense after all drawing is completed and display has been called. Not calling display after subsequent drawing will lead to undefined behavior if a mipmap had been previously generated.

Returns: true if mipmap generation was successful, false if unsuccessful

◆ getDefaultView()

const View & sf::RenderTarget::getDefaultView ( ) const

nodiscardinherited

Get the default view of the render target.

The default view has the initial size of the render target, and never changes after the target has been created.

Returns: The default view of the render target

See also: setView, getView

◆ getMaximumAntiAliasingLevel()

static unsigned int sf::RenderTexture::getMaximumAntiAliasingLevel ( )

staticnodiscard

Get the maximum anti-aliasing level supported by the system.

Returns: The maximum anti-aliasing level supported by the system

◆ getScissor()

IntRect sf::RenderTarget::getScissor ( const View & view ) const

nodiscardinherited

Get the scissor rectangle of a view, applied to this render target.

The scissor rectangle is defined in the view as a ratio. This function simply applies this ratio to the current dimensions of the render target to calculate the pixels rectangle that the scissor rectangle actually covers in the target.

Parameters

view	The view for which we want to compute the scissor rectangle

Returns: Scissor rectangle, expressed in pixels

◆ getSize()

Vector2u sf::RenderTexture::getSize ( ) const

nodiscardoverridevirtual

Return the size of the rendering region of the texture.

The returned value is the size that you passed to the create function.

Returns: Size in pixels

Implements sf::RenderTarget.

◆ getTexture()

const Texture & sf::RenderTexture::getTexture ( ) const

nodiscard

Get a read-only reference to the target texture.

After drawing to the render-texture and calling Display, you can retrieve the updated texture using this function, and draw it using a sprite (for example). The internal sf::Texture of a render-texture is always the same instance, so that it is possible to call this function once and keep a reference to the texture even after it is modified.

Returns: Const reference to the texture

◆ getView()

const View & sf::RenderTarget::getView ( ) const

nodiscardinherited

Get the view currently in use in the render target.

Returns: The view object that is currently used

See also: setView, getDefaultView

◆ getViewport()

IntRect sf::RenderTarget::getViewport ( const View & view ) const

nodiscardinherited

Get the viewport of a view, applied to this render target.

The viewport is defined in the view as a ratio, this function simply applies this ratio to the current dimensions of the render target to calculate the pixels rectangle that the viewport actually covers in the target.

Parameters

view	The view for which we want to compute the viewport

Returns: Viewport rectangle, expressed in pixels

◆ initialize()

void sf::RenderTarget::initialize ( )

protectedinherited

Performs the common initialization step after creation.

The derived classes must call this function after the target is created and ready for drawing.

◆ isRepeated()

bool sf::RenderTexture::isRepeated ( ) const

nodiscard

Tell whether the texture is repeated or not.

Returns: true if texture is repeated

See also: setRepeated

◆ isSmooth()

bool sf::RenderTexture::isSmooth ( ) const

nodiscard

Tell whether the smooth filtering is enabled or not.

Returns: true if texture smoothing is enabled

See also: setSmooth

◆ isSrgb()

bool sf::RenderTexture::isSrgb ( ) const

nodiscardoverridevirtual

Tell if the render-texture will use sRGB encoding when drawing on it.

You can request sRGB encoding for a render-texture by having the sRgbCapable flag set for the context parameter of create() method

Returns: true if the render-texture use sRGB encoding, false otherwise

Reimplemented from sf::RenderTarget.

◆ mapCoordsToPixel() [1/2]

Vector2i sf::RenderTarget::mapCoordsToPixel ( Vector2f point ) const

nodiscardinherited

Convert a point from world coordinates to target coordinates, using the current view.

This function is an overload of the mapCoordsToPixel function that implicitly uses the current view. It is equivalent to:

target.mapCoordsToPixel(point, target.getView());

Parameters

point Point to convert

Returns: The converted point, in target coordinates (pixels)

See also: mapPixelToCoords

◆ mapCoordsToPixel() [2/2]

Vector2i sf::RenderTarget::mapCoordsToPixel	(	Vector2f	point,
		const View &	view ) const

nodiscardinherited

Convert a point from world coordinates to target coordinates.

This function finds the pixel of the render target that matches the given 2D point. In other words, it goes through the same process as the graphics card, to compute the final position of a rendered point.

Initially, both coordinate systems (world units and target pixels) match perfectly. But if you define a custom view or resize your render target, this assertion is not true anymore, i.e. a point located at (150, 75) in your 2D world may map to the pixel (10, 50) of your render target – if the view is translated by (140, 25).

This version uses a custom view for calculations, see the other overload of the function if you want to use the current view of the render target.

Parameters

point	Point to convert
view	The view to use for converting the point

Returns: The converted point, in target coordinates (pixels)

See also: mapPixelToCoords

◆ mapPixelToCoords() [1/2]

Vector2f sf::RenderTarget::mapPixelToCoords ( Vector2i point ) const

nodiscardinherited

Convert a point from target coordinates to world coordinates, using the current view.

This function is an overload of the mapPixelToCoords function that implicitly uses the current view. It is equivalent to:

target.mapPixelToCoords(point, target.getView());

Parameters

point Pixel to convert

Returns: The converted point, in "world" coordinates

See also: mapCoordsToPixel

◆ mapPixelToCoords() [2/2]

Vector2f sf::RenderTarget::mapPixelToCoords	(	Vector2i	point,
		const View &	view ) const

nodiscardinherited

Convert a point from target coordinates to world coordinates.

This function finds the 2D position that matches the given pixel of the render target. In other words, it does the inverse of what the graphics card does, to find the initial position of a rendered pixel.

Initially, both coordinate systems (world units and target pixels) match perfectly. But if you define a custom view or resize your render target, this assertion is not true anymore, i.e. a point located at (10, 50) in your render target may map to the point (150, 75) in your 2D world – if the view is translated by (140, 25).

For render-windows, this function is typically used to find which point (or object) is located below the mouse cursor.

This version uses a custom view for calculations, see the other overload of the function if you want to use the current view of the render target.

Parameters

point	Pixel to convert
view	The view to use for converting the point

Returns: The converted point, in "world" units

See also: mapCoordsToPixel

◆ operator=() [1/2]

RenderTexture & sf::RenderTexture::operator= ( const RenderTexture & )

delete

Deleted copy assignment.

◆ operator=() [2/2]

RenderTexture & sf::RenderTexture::operator= ( RenderTexture && )

noexcept

Move assignment operator.

◆ popGLStates()

void sf::RenderTarget::popGLStates ( )

inherited

Restore the previously saved OpenGL render states and matrices.

See the description of pushGLStates to get a detailed description of these functions.

See also: pushGLStates

◆ pushGLStates()

void sf::RenderTarget::pushGLStates ( )

inherited

Save the current OpenGL render states and matrices.

This function can be used when you mix SFML drawing and direct OpenGL rendering. Combined with popGLStates, it ensures that:

SFML's internal states are not messed up by your OpenGL code
your OpenGL states are not modified by a call to a SFML function

More specifically, it must be used around code that calls draw functions. Example:

// OpenGL code here...
window.pushGLStates();
window.draw(...);
window.draw(...);
window.popGLStates();
// OpenGL code here...

Note that this function is quite expensive: it saves all the possible OpenGL states and matrices, even the ones you don't care about. Therefore it should be used wisely. It is provided for convenience, but the best results will be achieved if you handle OpenGL states yourself (because you know which states have really changed, and need to be saved and restored). Take a look at the resetGLStates function if you do so.

See also: popGLStates

◆ resetGLStates()

void sf::RenderTarget::resetGLStates ( )

inherited

Reset the internal OpenGL states so that the target is ready for drawing.

This function can be used when you mix SFML drawing and direct OpenGL rendering, if you choose not to use pushGLStates/popGLStates. It makes sure that all OpenGL states needed by SFML are set, so that subsequent draw() calls will work as expected.

Example:

// OpenGL code here...
glPushAttrib(...);
window.resetGLStates();
window.draw(...);
window.draw(...);
glPopAttrib(...);
// OpenGL code here...

◆ resize()

bool sf::RenderTexture::resize	(	Vector2u	size,
		const ContextSettings &	settings = {} )

nodiscard

Resize the render-texture.

The last parameter, settings, is useful if you want to enable multi-sampling or use the render-texture for OpenGL rendering that requires a depth or stencil buffer. Otherwise it is unnecessary, and you should leave this parameter at its default value.

After resizing, the contents of the render-texture are undefined. Call RenderTexture::clear first to ensure a single color fill.

Parameters

size	Width and height of the render-texture
settings	Additional settings for the underlying OpenGL texture and context

Returns: true if resizing has been successful, false if it failed

◆ setActive()

bool sf::RenderTexture::setActive ( bool active = true )

nodiscardoverridevirtual

Activate or deactivate the render-texture for rendering.

This function makes the render-texture's context current for future OpenGL rendering operations (so you shouldn't care about it if you're not doing direct OpenGL stuff). Only one context can be current in a thread, so if you want to draw OpenGL geometry to another render target (like a RenderWindow) don't forget to activate it again.

Parameters

active true to activate, false to deactivate

Returns: true if operation was successful, false otherwise

Reimplemented from sf::RenderTarget.

◆ setRepeated()

void sf::RenderTexture::setRepeated ( bool repeated )

Enable or disable texture repeating.

This function is similar to Texture::setRepeated. This parameter is disabled by default.

Parameters

repeated true to enable repeating, false to disable it

See also: isRepeated

◆ setSmooth()

void sf::RenderTexture::setSmooth ( bool smooth )

Enable or disable texture smoothing.

This function is similar to Texture::setSmooth. This parameter is disabled by default.

Parameters

smooth true to enable smoothing, false to disable it

See also: isSmooth

◆ setView()

void sf::RenderTarget::setView ( const View & view )

inherited

Change the current active view.

The view is like a 2D camera, it controls which part of the 2D scene is visible, and how it is viewed in the render target. The new view will affect everything that is drawn, until another view is set. The render target keeps its own copy of the view object, so it is not necessary to keep the original one alive after calling this function. To restore the original view of the target, you can pass the result of getDefaultView() to this function.

Parameters

view	New view to use

See also: getView, getDefaultView

The documentation for this class was generated from the following file:

RenderTexture.hpp

Public Member Functions

Static Public Member Functions

Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ RenderTexture() [1/4]

◆ RenderTexture() [2/4]

◆ ~RenderTexture()

◆ RenderTexture() [3/4]

◆ RenderTexture() [4/4]

Member Function Documentation

◆ clear() [1/2]

◆ clear() [2/2]

◆ clearStencil()

◆ display()

◆ draw() [1/4]

◆ draw() [2/4]

◆ draw() [3/4]

◆ draw() [4/4]

◆ generateMipmap()

◆ getDefaultView()

◆ getMaximumAntiAliasingLevel()

◆ getScissor()

◆ getSize()

◆ getTexture()

◆ getView()

◆ getViewport()

◆ initialize()

◆ isRepeated()

◆ isSmooth()

◆ isSrgb()

◆ mapCoordsToPixel() [1/2]

◆ mapCoordsToPixel() [2/2]

◆ mapPixelToCoords() [1/2]

◆ mapPixelToCoords() [2/2]

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ popGLStates()

◆ pushGLStates()

◆ resetGLStates()

◆ resize()

◆ setActive()

◆ setRepeated()

◆ setSmooth()

◆ setView()