Documentation of SFML 2.0

sf::Texture Class Reference

Image living on the graphics card that can be used for drawing. More...

#include <Texture.hpp>

Inheritance diagram for sf::Texture:
sf::GlResource

Public Types

enum  CoordinateType {
  Normalized,
  Pixels
}
 Types of texture coordinates that can be used for rendering. More...
 

Public Member Functions

 Texture ()
 Default constructor.
 
 Texture (const Texture &copy)
 Copy constructor.
 
 ~Texture ()
 Destructor.
 
bool create (unsigned int width, unsigned int height)
 Create the texture.
 
bool loadFromFile (const std::string &filename, const IntRect &area=IntRect())
 Load the texture from a file on disk.
 
bool loadFromMemory (const void *data, std::size_t size, const IntRect &area=IntRect())
 Load the texture from a file in memory.
 
bool loadFromStream (sf::InputStream &stream, const IntRect &area=IntRect())
 Load the texture from a custom stream.
 
bool loadFromImage (const Image &image, const IntRect &area=IntRect())
 Load the texture from an image.
 
Vector2u getSize () const
 Return the size of the texture.
 
Image copyToImage () const
 Copy the texture pixels to an image.
 
void update (const Uint8 *pixels)
 Update the whole texture from an array of pixels.
 
void update (const Uint8 *pixels, unsigned int width, unsigned int height, unsigned int x, unsigned int y)
 Update a part of the texture from an array of pixels.
 
void update (const Image &image)
 Update the texture from an image.
 
void update (const Image &image, unsigned int x, unsigned int y)
 Update a part of the texture from an image.
 
void update (const Window &window)
 Update the texture from the contents of a window.
 
void update (const Window &window, unsigned int x, unsigned int y)
 Update a part of the texture from the contents of a window.
 
void setSmooth (bool smooth)
 Enable or disable the smooth filter.
 
bool isSmooth () const
 Tell whether the smooth filter is enabled or not.
 
void setRepeated (bool repeated)
 Enable or disable repeating.
 
bool isRepeated () const
 Tell whether the texture is repeated or not.
 
Textureoperator= (const Texture &right)
 Overload of assignment operator.
 

Static Public Member Functions

static void bind (const Texture *texture, CoordinateType coordinateType=Normalized)
 Bind a texture for rendering.
 
static unsigned int getMaximumSize ()
 Get the maximum texture size allowed.
 

Static Private Member Functions

static void ensureGlContext ()
 Make sure that a valid OpenGL context exists in the current thread.
 

Friends

class RenderTexture
 
class RenderTarget
 

Detailed Description

Image living on the graphics card that can be used for drawing.

sf::Texture stores pixels that can be drawn, with a sprite for example.

A texture lives in the graphics card memory, therefore it is very fast to draw a texture to a render target, or copy a render target to a texture (the graphics card can access both directly).

Being stored in the graphics card memory has some drawbacks. A texture cannot be manipulated as freely as a sf::Image, you need to prepare the pixels first and then upload them to the texture in a single operation (see Texture::update).

sf::Texture makes it easy to convert from/to sf::Image, but keep in mind that these calls require transfers between the graphics card and the central memory, therefore they are slow operations.

A texture can be loaded from an image, but also directly from a file/memory/stream. The necessary shortcuts are defined so that you don't need an image first for the most common cases. However, if you want to perform some modifications on the pixels before creating the final texture, you can load your file to a sf::Image, do whatever you need with the pixels, and then call Texture::loadFromImage.

Since they live in the graphics card memory, the pixels of a texture cannot be accessed without a slow copy first. And they cannot be accessed individually. Therefore, if you need to read the texture's pixels (like for pixel-perfect collisions), it is recommended to store the collision information separately, for example in an array of booleans.

Like sf::Image, sf::Texture can handle a unique internal representation of pixels, which is RGBA 32 bits. This means that a pixel must be composed of 8 bits red, green, blue and alpha channels – just like a sf::Color.

Usage example:

// This example shows the most common use of sf::Texture:
// drawing a sprite
// Load a texture from a file
sf::Texture texture;
if (!texture.loadFromFile("texture.png"))
return -1;
// Assign it to a sprite
sf::Sprite sprite;
sprite.setTexture(texture);
// Draw the textured sprite
window.draw(sprite);
// This example shows another common use of sf::Texture:
// streaming real-time data, like video frames
// Create an empty texture
sf::Texture texture;
if (!texture.create(640, 480))
return -1;
// Create a sprite that will display the texture
sf::Sprite sprite(texture);
while (...) // the main loop
{
...
// update the texture
sf::Uint8* pixels = ...; // get a fresh chunk of pixels (the next frame of a movie, for example)
texture.update(pixels);
// draw it
window.draw(sprite);
...
}

Like sf::Shader that can be used as a raw OpenGL shader, sf::Texture can also be used directly as a raw texture for custom OpenGL geometry.

... render OpenGL geometry ...
sf::Texture::bind(NULL);
See Also
sf::Sprite, sf::Image, sf::RenderTexture

Definition at line 47 of file Texture.hpp.

Member Enumeration Documentation

Types of texture coordinates that can be used for rendering.

Enumerator:
Normalized 

Texture coordinates in range [0 .. 1].

Pixels 

Texture coordinates in range [0 .. size].

Definition at line 55 of file Texture.hpp.

Constructor & Destructor Documentation

sf::Texture::Texture ( )

Default constructor.

Creates an empty texture.

sf::Texture::Texture ( const Texture copy)

Copy constructor.

Parameters
copyinstance to copy
sf::Texture::~Texture ( )

Destructor.

Member Function Documentation

static void sf::Texture::bind ( const Texture texture,
CoordinateType  coordinateType = Normalized 
)
static

Bind a texture for rendering.

This function is not part of the graphics API, it mustn't be used when drawing SFML entities. It must be used only if you mix sf::Texture with OpenGL code.

sf::Texture t1, t2;
...
sf::Texture::bind(&t1);
// draw OpenGL stuff that use t1...
// draw OpenGL stuff that use t2...
// draw OpenGL stuff that use no texture...

The coordinateType argument controls how texture coordinates will be interpreted. If Normalized (the default), they must be in range [0 .. 1], which is the default way of handling texture coordinates with OpenGL. If Pixels, they must be given in pixels (range [0 .. size]). This mode is used internally by the graphics classes of SFML, it makes the definition of texture coordinates more intuitive for the high-level API, users don't need to compute normalized values.

Parameters
texturePointer to the texture to bind, can be null to use no texture
coordinateTypeType of texture coordinates to use
Image sf::Texture::copyToImage ( ) const

Copy the texture pixels to an image.

This function performs a slow operation that downloads the texture's pixels from the graphics card and copies them to a new image, potentially applying transformations to pixels if necessary (texture may be padded or flipped).

Returns
Image containing the texture's pixels
See Also
loadFromImage
bool sf::Texture::create ( unsigned int  width,
unsigned int  height 
)

Create the texture.

If this function fails, the texture is left unchanged.

Parameters
widthWidth of the texture
heightHeight of the texture
Returns
True if creation was successful
static unsigned int sf::Texture::getMaximumSize ( )
static

Get the maximum texture size allowed.

This maximum size is defined by the graphics driver. You can expect a value of 512 pixels for low-end graphics card, and up to 8192 pixels or more for newer hardware.

Returns
Maximum size allowed for textures, in pixels
Vector2u sf::Texture::getSize ( ) const

Return the size of the texture.

Returns
Size in pixels
bool sf::Texture::isRepeated ( ) const

Tell whether the texture is repeated or not.

Returns
True if repeat mode is enabled, false if it is disabled
See Also
setRepeated
bool sf::Texture::isSmooth ( ) const

Tell whether the smooth filter is enabled or not.

Returns
True if smoothing is enabled, false if it is disabled
See Also
setSmooth
bool sf::Texture::loadFromFile ( const std::string &  filename,
const IntRect area = IntRect() 
)

Load the texture from a file on disk.

This function is a shortcut for the following code:

sf::Image image;
image.loadFromFile(filename);
texture.loadFromImage(image, area);

The area argument can be used to load only a sub-rectangle of the whole image. If you want the entire image then leave the default value (which is an empty IntRect). If the area rectangle crosses the bounds of the image, it is adjusted to fit the image size.

The maximum size for a texture depends on the graphics driver and can be retrieved with the getMaximumSize function.

If this function fails, the texture is left unchanged.

Parameters
filenamePath of the image file to load
areaArea of the image to load
Returns
True if loading was successful
See Also
loadFromMemory, loadFromStream, loadFromImage
bool sf::Texture::loadFromImage ( const Image image,
const IntRect area = IntRect() 
)

Load the texture from an image.

The area argument can be used to load only a sub-rectangle of the whole image. If you want the entire image then leave the default value (which is an empty IntRect). If the area rectangle crosses the bounds of the image, it is adjusted to fit the image size.

The maximum size for a texture depends on the graphics driver and can be retrieved with the getMaximumSize function.

If this function fails, the texture is left unchanged.

Parameters
imageImage to load into the texture
areaArea of the image to load
Returns
True if loading was successful
See Also
loadFromFile, loadFromMemory
bool sf::Texture::loadFromMemory ( const void *  data,
std::size_t  size,
const IntRect area = IntRect() 
)

Load the texture from a file in memory.

This function is a shortcut for the following code:

sf::Image image;
image.loadFromMemory(data, size);
texture.loadFromImage(image, area);

The area argument can be used to load only a sub-rectangle of the whole image. If you want the entire image then leave the default value (which is an empty IntRect). If the area rectangle crosses the bounds of the image, it is adjusted to fit the image size.

The maximum size for a texture depends on the graphics driver and can be retrieved with the getMaximumSize function.

If this function fails, the texture is left unchanged.

Parameters
dataPointer to the file data in memory
sizeSize of the data to load, in bytes
areaArea of the image to load
Returns
True if loading was successful
See Also
loadFromFile, loadFromStream, loadFromImage
bool sf::Texture::loadFromStream ( sf::InputStream stream,
const IntRect area = IntRect() 
)

Load the texture from a custom stream.

This function is a shortcut for the following code:

sf::Image image;
image.loadFromStream(stream);
texture.loadFromImage(image, area);

The area argument can be used to load only a sub-rectangle of the whole image. If you want the entire image then leave the default value (which is an empty IntRect). If the area rectangle crosses the bounds of the image, it is adjusted to fit the image size.

The maximum size for a texture depends on the graphics driver and can be retrieved with the getMaximumSize function.

If this function fails, the texture is left unchanged.

Parameters
streamSource stream to read from
areaArea of the image to load
Returns
True if loading was successful
See Also
loadFromFile, loadFromMemory, loadFromImage
Texture& sf::Texture::operator= ( const Texture right)

Overload of assignment operator.

Parameters
rightInstance to assign
Returns
Reference to self
void sf::Texture::setRepeated ( bool  repeated)

Enable or disable repeating.

Repeating is involved when using texture coordinates outside the texture rectangle [0, 0, width, height]. In this case, if repeat mode is enabled, the whole texture will be repeated as many times as needed to reach the coordinate (for example, if the X texture coordinate is 3 * width, the texture will be repeated 3 times). If repeat mode is disabled, the "extra space" will instead be filled with border pixels. Warning: on very old graphics cards, white pixels may appear when the texture is repeated. With such cards, repeat mode can be used reliably only if the texture has power-of-two dimensions (such as 256x128). Repeating is disabled by default.

Parameters
repeatedTrue to repeat the texture, false to disable repeating
See Also
isRepeated
void sf::Texture::setSmooth ( bool  smooth)

Enable or disable the smooth filter.

When the filter is activated, the texture appears smoother so that pixels are less noticeable. However if you want the texture to look exactly the same as its source file, you should leave it disabled. The smooth filter is disabled by default.

Parameters
smoothTrue to enable smoothing, false to disable it
See Also
isSmooth
void sf::Texture::update ( const Uint8 *  pixels)

Update the whole texture from an array of pixels.

The pixel array is assumed to have the same size as the area rectangle, and to contain 32-bits RGBA pixels.

No additional check is performed on the size of the pixel array, passing invalid arguments will lead to an undefined behaviour.

This function does nothing if pixels is null or if the texture was not previously created.

Parameters
pixelsArray of pixels to copy to the texture
void sf::Texture::update ( const Uint8 *  pixels,
unsigned int  width,
unsigned int  height,
unsigned int  x,
unsigned int  y 
)

Update a part of the texture from an array of pixels.

The size of the pixel array must match the width and height arguments, and it must contain 32-bits RGBA pixels.

No additional check is performed on the size of the pixel array or the bounds of the area to update, passing invalid arguments will lead to an undefined behaviour.

This function does nothing if pixels is null or if the texture was not previously created.

Parameters
pixelsArray of pixels to copy to the texture
widthWidth of the pixel region contained in pixels
heightHeight of the pixel region contained in pixels
xX offset in the texture where to copy the source pixels
yY offset in the texture where to copy the source pixels
void sf::Texture::update ( const Image image)

Update the texture from an image.

Although the source image can be smaller than the texture, this function is usually used for updating the whole texture. The other overload, which has (x, y) additional arguments, is more convenient for updating a sub-area of the texture.

No additional check is performed on the size of the image, passing an image bigger than the texture will lead to an undefined behaviour.

This function does nothing if the texture was not previously created.

Parameters
imageImage to copy to the texture
void sf::Texture::update ( const Image image,
unsigned int  x,
unsigned int  y 
)

Update a part of the texture from an image.

No additional check is performed on the size of the image, passing an invalid combination of image size and offset will lead to an undefined behaviour.

This function does nothing if the texture was not previously created.

Parameters
imageImage to copy to the texture
xX offset in the texture where to copy the source image
yY offset in the texture where to copy the source image
void sf::Texture::update ( const Window window)

Update the texture from the contents of a window.

Although the source window can be smaller than the texture, this function is usually used for updating the whole texture. The other overload, which has (x, y) additional arguments, is more convenient for updating a sub-area of the texture.

No additional check is performed on the size of the window, passing a window bigger than the texture will lead to an undefined behaviour.

This function does nothing if either the texture or the window was not previously created.

Parameters
windowWindow to copy to the texture
void sf::Texture::update ( const Window window,
unsigned int  x,
unsigned int  y 
)

Update a part of the texture from the contents of a window.

No additional check is performed on the size of the window, passing an invalid combination of window size and offset will lead to an undefined behaviour.

This function does nothing if either the texture or the window was not previously created.

Parameters
windowWindow to copy to the texture
xX offset in the texture where to copy the source window
yY offset in the texture where to copy the source window

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