gf::RenderTexture Class Reference

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

#include <gf/RenderTexture.h>

Inheritance diagram for gf::RenderTexture:

Public Member Functions
	RenderTexture (Vector2i size)
	Create the render-texture. More...
void	setSmooth (bool smooth=true)
	Enable or disable texture smoothing. More...
bool	isSmooth () const
	Check if the smooth filtering is enabled or not. More...
void	setRepeated (bool repeated=true)
	Enable or disable texture repeating. More...
bool	isRepeated () const
	Check if the texture is repeated or not. More...
Vector2i	getSize () const override
	Return the size of the rendering region of the target. More...
void	resize (Vector2i size)
	Resize the underlying texture. More...
void	setActive () override
	Activate the render target for rendering. More...
void	display ()
	Update the contents of the target texture. More...
Image	capture () const
	Copy the current contents of the render texture to an image. More...
const Texture &	getTexture () const
	Get a read-only reference to the target texture. More...
Public Member Functions inherited from gf::RenderTarget
	RenderTarget (Vector2i size)
	Constructor. More...
virtual	~RenderTarget ()
	Destructor. More...
	RenderTarget (const RenderTarget &)=delete
	Deleted copy constructor. More...
RenderTarget &	operator= (const RenderTarget &)=delete
	Deleted copy assignment. More...
virtual Vector2i	getSize () const =0
	Return the size of the rendering region of the target. More...
virtual void	setActive ()
	Activate the render target for rendering. More...
Region	getCanonicalScissorBox ()
	Get the current canonical scissor box. More...
void	setCanonicalScissorBox (const Region &box)
	Define the canonical scissor box. More...
RectI	getScissorBox ()
	Get the current scissor box. More...
void	setScissorBox (const RectI &box)
	Define the scissor box. More...
void	clear (const Color4f &color)
	Clear the entire target with a single color. More...
void	clear ()
	Clear the entire target. More...
RangeF	getAliasedLineWidthRange () const
	Get the range for aliased line width. More...
float	getLineWidth () const
	Get the line width. More...
void	draw (const Vertex *vertices, std::size_t count, PrimitiveType type, const RenderStates &states=RenderStates())
	Draw primitives defined by an array of vertices. More...
void	draw (const Vertex *vertices, const uint16_t *indices, std::size_t count, PrimitiveType type, const RenderStates &states=RenderStates())
	Draw primitives defined by an array of vertices and their indices. More...
void	draw (const VertexBuffer &buffer, const RenderStates &states=RenderStates())
	Draw a vertex buffer to the render target. More...
void	draw (Drawable &drawable, const RenderStates &states=RenderStates())
	Draw a drawable object to the render target. More...
void	customDraw (const void *vertices, std::size_t size, std::size_t count, PrimitiveType type, Span< const RenderAttributeInfo > attributes, const RenderStates &states=RenderStates())
	Draw primitives defined by an array of custom vertices. More...
void	customDraw (const void *vertices, std::size_t size, const uint16_t *indices, std::size_t count, PrimitiveType type, Span< const RenderAttributeInfo > attributes, const RenderStates &states=RenderStates())
	Draw primitives defined by an array of custom vertices and their indices. More...
void	customDraw (const VertexBuffer &buffer, Span< const RenderAttributeInfo > attributes, const RenderStates &states=RenderStates())
	Draw a custom vertex buffer to the render target. More...
void	setView (const View &view)
	Change the current active view. More...
const View &	getView () const
	Get the view currently in use in the render target. More...
Region	getCanonicalViewport (const View &view) const
	Get the canonical viewport of a view, applied to this render target. More...
RectI	getViewport (const View &view) const
	Get the viewport of a view, applied to this render target. More...
Vector2f	mapPixelToCoords (Vector2i point, const View &view) const
	Convert a point from target coordinates to world coordinates. More...
Vector2f	mapPixelToCoords (Vector2i point) const
	Convert a point from target coordinates to world coordinates, using the current view. More...
Vector2i	mapCoordsToPixel (Vector2f point, const View &view) const
	Convert a point from world coordinates to target coordinates. More...
Vector2i	mapCoordsToPixel (Vector2f point) const
	Convert a point from world coordinates to target coordinates, using the current view. More...

Additional Inherited Members
Protected Member Functions inherited from gf::RenderTarget
Image	captureFramebuffer (unsigned name) const
	Capture the given framebuffer. More...

Detailed Description

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

gf::RenderTexture is the little brother of gf::RenderWindow. It implements the same 2D drawing and OpenGL-related functions (see their base class gf::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 (See gf::PostProcessing)
• creating a sprite from a 3D object rendered with OpenGL
• etc.

Usage example:

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

See also

gf::RenderTarget, gf::RenderWindow, gf::View, gf::Texture

Constructor & Destructor Documentation

RenderTexture()

gf::RenderTexture::RenderTexture

(

Vector2i

size

)

Create the render-texture.

Parameters

size	Size of the render-texture

Member Function Documentation

capture()

Image gf::RenderTexture::capture

(

)

const

Copy the current contents of the render texture to an image.

This is a slow operation, whose main purpose is to make screenshots of the application.

display()

void gf::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.

getSize()

Vector2i gf::RenderTexture::getSize ( ) const

overridevirtual

Return the size of the rendering region of the target.

Returns

Size in pixels

Implements gf::RenderTarget.

getTexture()

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

inline

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

isRepeated()

bool gf::RenderTexture::isRepeated ( ) const

inline

Check if the texture is repeated or not.

Returns

True if texture is repeated

See also

setRepeated()

isSmooth()

bool gf::RenderTexture::isSmooth ( ) const

inline

Check if the smooth filtering is enabled or not.

Returns

True if texture smoothing is enabled

See also

setSmooth()

resize()

void gf::RenderTexture::resize

(

Vector2i

size

)

Resize the underlying texture.

Parameters

size	The new size

setActive()

void gf::RenderTexture::setActive ( )

overridevirtual

Activate the render target for rendering.

This function activates the render target. You should call this function before you want to draw something to the target.

Reimplemented from gf::RenderTarget.

setRepeated()

void gf::RenderTexture::setRepeated ( bool  repeated = true )

inline

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 gf::RenderTexture::setSmooth ( bool  smooth = true )

inline

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()