JavaTM 2 Platform Std. Ed. v1.6.0
java.awt.image.renderable
Interface RenderableImage
- All Known Implementing Classes:
- RenderableImageOp
public interface RenderableImage
A RenderableImage is a common interface for rendering-independent
images (a notion which subsumes resolution independence). That is,
images which are described and have operations applied to them
independent of any specific rendering of the image. For example, a
RenderableImage can be rotated and cropped in
resolution-independent terms. Then, it can be rendered for various
specific contexts, such as a draft preview, a high-quality screen
display, or a printer, each in an optimal fashion.
A RenderedImage is returned from a RenderableImage via the
createRendering() method, which takes a RenderContext. The
RenderContext specifies how the RenderedImage should be
constructed. Note that it is not possible to extract pixels
directly from a RenderableImage.
The createDefaultRendering() and createScaledRendering() methods are
convenience methods that construct an appropriate RenderContext
internally. All of the rendering methods may return a reference to a
previously produced rendering.
Field Summary |
static String |
HINTS_OBSERVED
String constant that can be used to identify a property on
a RenderedImage obtained via the createRendering or
createScaledRendering methods. |
Method Summary |
RenderedImage |
createDefaultRendering()
Returnd a RenderedImage instance of this image with a default
width and height in pixels. |
RenderedImage |
createRendering(RenderContext renderContext)
Creates a RenderedImage that represented a rendering of this image
using a given RenderContext. |
RenderedImage |
createScaledRendering(int w,
int h,
RenderingHints hints)
Creates a RenderedImage instance of this image with width w, and
height h in pixels. |
float |
getHeight()
Gets the height in user coordinate space. |
float |
getMinX()
Gets the minimum X coordinate of the rendering-independent image data. |
float |
getMinY()
Gets the minimum Y coordinate of the rendering-independent image data. |
Object |
getProperty(String name)
Gets a property from the property set of this image. |
String[] |
getPropertyNames()
Returns a list of names recognized by getProperty. |
Vector<RenderableImage> |
getSources()
Returns a vector of RenderableImages that are the sources of
image data for this RenderableImage. |
float |
getWidth()
Gets the width in user coordinate space. |
boolean |
isDynamic()
Returns true if successive renderings (that is, calls to
createRendering() or createScaledRendering()) with the same arguments
may produce different results. |
HINTS_OBSERVED
static final String HINTS_OBSERVED
- String constant that can be used to identify a property on
a RenderedImage obtained via the createRendering or
createScaledRendering methods. If such a property exists,
the value of the propoery will be a RenderingHints object
specifying which hints were observed in creating the rendering.
- See Also:
- Constant Field Values
getSources
Vector<RenderableImage> getSources()
- Returns a vector of RenderableImages that are the sources of
image data for this RenderableImage. Note that this method may
return an empty vector, to indicate that the image has no sources,
or null, to indicate that no information is available.
- Returns:
- a (possibly empty) Vector of RenderableImages, or null.
getProperty
Object getProperty(String name)
- Gets a property from the property set of this image.
If the property name is not recognized, java.awt.Image.UndefinedProperty
will be returned.
- Parameters:
name - the name of the property to get, as a String.
- Returns:
- a reference to the property Object, or the value
java.awt.Image.UndefinedProperty.
getPropertyNames
String[] getPropertyNames()
- Returns a list of names recognized by getProperty.
- Returns:
- a list of property names.
isDynamic
boolean isDynamic()
- Returns true if successive renderings (that is, calls to
createRendering() or createScaledRendering()) with the same arguments
may produce different results. This method may be used to
determine whether an existing rendering may be cached and
reused. It is always safe to return true.
- Returns:
true if successive renderings with the
same arguments might produce different results;
false otherwise.
getWidth
float getWidth()
- Gets the width in user coordinate space. By convention, the
usual width of a RenderableImage is equal to the image's aspect
ratio (width divided by height).
- Returns:
- the width of the image in user coordinates.
getHeight
float getHeight()
- Gets the height in user coordinate space. By convention, the
usual height of a RenderedImage is equal to 1.0F.
- Returns:
- the height of the image in user coordinates.
getMinX
float getMinX()
- Gets the minimum X coordinate of the rendering-independent image data.
- Returns:
- the minimum X coordinate of the rendering-independent image
data.
getMinY
float getMinY()
- Gets the minimum Y coordinate of the rendering-independent image data.
- Returns:
- the minimum Y coordinate of the rendering-independent image
data.
createScaledRendering
RenderedImage createScaledRendering(int w,
int h,
RenderingHints hints)
- Creates a RenderedImage instance of this image with width w, and
height h in pixels. The RenderContext is built automatically
with an appropriate usr2dev transform and an area of interest
of the full image. All the rendering hints come from hints
passed in.
If w == 0, it will be taken to equal
Math.round(h*(getWidth()/getHeight())).
Similarly, if h == 0, it will be taken to equal
Math.round(w*(getHeight()/getWidth())). One of
w or h must be non-zero or else an IllegalArgumentException
will be thrown.
The created RenderedImage may have a property identified
by the String HINTS_OBSERVED to indicate which RenderingHints
were used to create the image. In addition any RenderedImages
that are obtained via the getSources() method on the created
RenderedImage may have such a property.
- Parameters:
w - the width of rendered image in pixels, or 0.h - the height of rendered image in pixels, or 0.hints - a RenderingHints object containg hints.
- Returns:
- a RenderedImage containing the rendered data.
createDefaultRendering
RenderedImage createDefaultRendering()
- Returnd a RenderedImage instance of this image with a default
width and height in pixels. The RenderContext is built
automatically with an appropriate usr2dev transform and an area
of interest of the full image. The rendering hints are
empty. createDefaultRendering may make use of a stored
rendering for speed.
- Returns:
- a RenderedImage containing the rendered data.
createRendering
RenderedImage createRendering(RenderContext renderContext)
- Creates a RenderedImage that represented a rendering of this image
using a given RenderContext. This is the most general way to obtain a
rendering of a RenderableImage.
The created RenderedImage may have a property identified
by the String HINTS_OBSERVED to indicate which RenderingHints
(from the RenderContext) were used to create the image.
In addition any RenderedImages
that are obtained via the getSources() method on the created
RenderedImage may have such a property.
- Parameters:
renderContext - the RenderContext to use to produce the rendering.
- Returns:
- a RenderedImage containing the rendered data.
Copyright 2003 Sun Microsystems, Inc. All rights reserved
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