Package | starling.textures |
Class | public class Texture |
Inheritance | Texture ![]() |
Subclasses | ConcreteTexture, SubTexture |
A texture stores the information that represents an image. It cannot be added to the display list directly; instead it has to be mapped onto a display object. In Starling, that display object is the class "Image".
Texture FormatsSince textures can be created from a "BitmapData" object, Starling supports any bitmap format that is supported by Flash. And since you can render any Flash display object into a BitmapData object, you can use this to display non-Starling content in Starling - e.g. Shape objects.
Starling also supports ATF textures (Adobe Texture Format), which is a container for compressed texture formats that can be rendered very efficiently by the GPU. Refer to the Flash documentation for more information about this format.
Mip MappingMipMaps are scaled down versions of a texture. When an image is displayed smaller than its natural size, the GPU may display the mip maps instead of the original texture. This reduces aliasing and accelerates rendering. It does, however, also need additional memory; for that reason, you can choose if you want to create them or not.
Texture FrameThe frame property of a texture allows you let a texture appear inside the bounds of an image, leaving a transparent space around the texture. The frame rectangle is specified in the coordinate system of the texture (not the image):
var frame:Rectangle = new Rectangle(-10, -10, 30, 30); var texture:Texture = Texture.fromTexture(anotherTexture, null, frame); var image:Image = new Image(texture);
This code would create an image with a size of 30x30, with the texture placed at
x=10, y=10
within that image (assuming that 'anotherTexture' has a width and
height of 10 pixels, it would appear in the middle of the image).
The texture atlas makes use of this feature, as it allows to crop transparent edges of a texture and making up for the changed size by specifying the original texture frame. Tools like TexturePacker use this to optimize the atlas.
Texture CoordinatesIf, on the other hand, you want to show only a part of the texture in an image (i.e. to crop the the texture), you can either create a subtexture (with the method 'Texture.fromTexture()' and specifying a rectangle for the region), or you can manipulate the texture coordinates of the image object. The method 'image.setTexCoords' allows you to do that.
See also
Property | Defined By | ||
---|---|---|---|
base : TextureBase [read-only] The Stage3D texture object the texture is based on. | Texture | ||
format : String [read-only] The Context3DTextureFormat of the underlying texture data. | Texture | ||
frame : Rectangle [read-only] The texture frame (see class description). | Texture | ||
height : Number [read-only] The height of the texture in points. | Texture | ||
mipMapping : Boolean [read-only] Indicates if the texture contains mip maps. | Texture | ||
nativeHeight : Number [read-only] The height of the texture in pixels (without scale adjustment). | Texture | ||
nativeWidth : Number [read-only] The width of the texture in pixels (without scale adjustment). | Texture | ||
premultipliedAlpha : Boolean [read-only] Indicates if the alpha values are premultiplied into the RGB values. | Texture | ||
repeat : Boolean Indicates if the texture should repeat like a wallpaper or stretch the outermost pixels. | Texture | ||
root : ConcreteTexture [read-only] The concrete (power-of-two) texture the texture is based on. | Texture | ||
scale : Number [read-only] The scale factor, which influences width and height properties. | Texture | ||
width : Number [read-only] The width of the texture in points. | Texture |
Method | Defined By | ||
---|---|---|---|
adjustVertexData(vertexData:VertexData, vertexID:int, count:int):void Converts texture coordinates and vertex positions of raw vertex data into the format
required for rendering. | Texture | ||
dispose():void Disposes the underlying texture data. | Texture | ||
empty(width:int = 64, height:int = 64, premultipliedAlpha:Boolean = false, optimizeForRenderToTexture:Boolean = true, scale:Number = -1):Texture [static] Creates an empty texture of a certain size. | Texture | ||
fromAtfData(data:ByteArray, scale:Number = 1, useMipMaps:Boolean = true, loadAsync:Function = null):Texture [static] Creates a texture from the compressed ATF format. | Texture | ||
fromBitmap(data:Bitmap, generateMipMaps:Boolean = true, optimizeForRenderToTexture:Boolean = false, scale:Number = 1):Texture [static] Creates a texture object from a bitmap. | Texture | ||
fromBitmapData(data:BitmapData, generateMipMaps:Boolean = true, optimizeForRenderToTexture:Boolean = false, scale:Number = 1):Texture [static] Creates a texture from bitmap data. | Texture | ||
fromColor(width:int, height:int, color:uint = 0xffffffff, optimizeForRenderToTexture:Boolean = false, scale:Number = -1):Texture [static] Creates a texture with a certain size and color. | Texture | ||
[static] Creates a texture that contains a region (in pixels) of another texture. | Texture |
base | property |
base:TextureBase
[read-only] The Stage3D texture object the texture is based on.
public function get base():TextureBase
format | property |
format:String
[read-only] The Context3DTextureFormat
of the underlying texture data.
public function get format():String
frame | property |
frame:Rectangle
[read-only] The texture frame (see class description).
public function get frame():Rectangle
height | property |
height:Number
[read-only] The height of the texture in points.
public function get height():Number
mipMapping | property |
mipMapping:Boolean
[read-only] Indicates if the texture contains mip maps.
public function get mipMapping():Boolean
nativeHeight | property |
nativeHeight:Number
[read-only] The height of the texture in pixels (without scale adjustment).
public function get nativeHeight():Number
nativeWidth | property |
nativeWidth:Number
[read-only] The width of the texture in pixels (without scale adjustment).
public function get nativeWidth():Number
premultipliedAlpha | property |
premultipliedAlpha:Boolean
[read-only] Indicates if the alpha values are premultiplied into the RGB values.
public function get premultipliedAlpha():Boolean
repeat | property |
repeat:Boolean
Indicates if the texture should repeat like a wallpaper or stretch the outermost pixels. Note: this only works in textures with sidelengths that are powers of two and that are not loaded from a texture atlas (i.e. no subtextures).
The default value is false
.
public function get repeat():Boolean
public function set repeat(value:Boolean):void
root | property |
root:ConcreteTexture
[read-only] The concrete (power-of-two) texture the texture is based on.
public function get root():ConcreteTexture
scale | property |
scale:Number
[read-only] The scale factor, which influences width and height properties.
public function get scale():Number
width | property |
width:Number
[read-only] The width of the texture in points.
public function get width():Number
adjustVertexData | () | method |
public function adjustVertexData(vertexData:VertexData, vertexID:int, count:int):void
Converts texture coordinates and vertex positions of raw vertex data into the format required for rendering.
Parameters
vertexData:VertexData | |
vertexID:int | |
count:int |
dispose | () | method |
public function dispose():void
Disposes the underlying texture data. Note that not all textures need to be disposed: SubTextures (created with 'Texture.fromTexture') just reference other textures and and do not take up resources themselves; this is also true for textures from an atlas.
empty | () | method |
public static function empty(width:int = 64, height:int = 64, premultipliedAlpha:Boolean = false, optimizeForRenderToTexture:Boolean = true, scale:Number = -1):Texture
Creates an empty texture of a certain size. Useful mainly for render textures. Beware that the texture can only be used after you either upload some color data or clear the texture while it is an active render target.
Parameters
width:int (default = 64 ) — in points; number of pixels depends on scale parameter
| |
height:int (default = 64 ) — in points; number of pixels depends on scale parameter
| |
premultipliedAlpha:Boolean (default = false ) — the PMA format you will use the texture with
| |
optimizeForRenderToTexture:Boolean (default = true ) — indicates if this texture will be used as render target
| |
scale:Number (default = -1 ) — if you omit this parameter, 'Starling.contentScaleFactor' will be used.
|
Texture |
fromAtfData | () | method |
public static function fromAtfData(data:ByteArray, scale:Number = 1, useMipMaps:Boolean = true, loadAsync:Function = null):Texture
Creates a texture from the compressed ATF format. If you don't want to use any embedded
mipmaps, you can disable them by setting "useMipMaps" to false
.
Beware: you must not dispose 'data' if Starling should handle a lost device context.
If you pass a function for the 'loadAsync' parameter, the method will return
immediately, while the texture will be created asynchronously. It can be used as soon
as the callback has been executed. This is the expected function definition:
function(texture:Texture):void;
Parameters
data:ByteArray | |
scale:Number (default = 1 )
| |
useMipMaps:Boolean (default = true )
| |
loadAsync:Function (default = null )
|
Texture |
fromBitmap | () | method |
public static function fromBitmap(data:Bitmap, generateMipMaps:Boolean = true, optimizeForRenderToTexture:Boolean = false, scale:Number = 1):Texture
Creates a texture object from a bitmap. Beware: you must not dispose 'data' if Starling should handle a lost device context.
Parameters
data:Bitmap | |
generateMipMaps:Boolean (default = true )
| |
optimizeForRenderToTexture:Boolean (default = false )
| |
scale:Number (default = 1 )
|
Texture |
fromBitmapData | () | method |
public static function fromBitmapData(data:BitmapData, generateMipMaps:Boolean = true, optimizeForRenderToTexture:Boolean = false, scale:Number = 1):Texture
Creates a texture from bitmap data. Beware: you must not dispose 'data' if Starling should handle a lost device context.
Parameters
data:BitmapData | |
generateMipMaps:Boolean (default = true )
| |
optimizeForRenderToTexture:Boolean (default = false )
| |
scale:Number (default = 1 )
|
Texture |
fromColor | () | method |
public static function fromColor(width:int, height:int, color:uint = 0xffffffff, optimizeForRenderToTexture:Boolean = false, scale:Number = -1):Texture
Creates a texture with a certain size and color.
Parameters
width:int — in points; number of pixels depends on scale parameter
| |
height:int — in points; number of pixels depends on scale parameter
| |
color:uint (default = 0xffffffff ) — expected in ARGB format (inlude alpha!)
| |
optimizeForRenderToTexture:Boolean (default = false ) — indicates if this texture will be used as render target
| |
scale:Number (default = -1 ) — if you omit this parameter, 'Starling.contentScaleFactor' will be used.
|
Texture |
fromTexture | () | method |
public static function fromTexture(texture:Texture, region:Rectangle = null, frame:Rectangle = null):Texture
Creates a texture that contains a region (in pixels) of another texture. The new texture will reference the base texture; no data is duplicated.
Parameters
texture:Texture | |
region:Rectangle (default = null )
| |
frame:Rectangle (default = null )
|
Texture |