This is a specialized interface for bitmaps having integer color
channels. In contrast to XIntegerBitmap, this
interface only permits read-only access.
Use this interface for e.g. bitmaps that are calculated
on-the-fly, or that are pure functional, and thus cannot be
modified.
If you get passed an instance of
XIntegerReadOnlyBitmap that also supports the
XVolatileBitmap interface, things become a bit more
complicated. When reading data, one has to check for both
VolatileContentDestroyedException and mismatching
IntegerBitmapLayout return values. If either of them
occurs, the whole bitmap read operation should be repeated, if you
need consistent information.
Query the raw data of this bitmap, in the format as defined by
getMemoryLayout(). With the given rectangle, a subset of the
whole bitmap can be queried. If the internal data format's
pixel are not integer multiples of bytes (i.e. if one pixel
occupies less than a byte), the leftover content of the bytes
at the right of each scanline is filled with zeros. The
details of the scanline padding are to be retrieved from the
passed bitmap layout.
Note that the bitmap memory layout might change over time for
volatile bitmaps.
Parameter bitmapLayout
The memory layout the returned data is in. Note that the color
space returned therein needs to always match the current color
space as would have been returned by getMemoryLayout(). This
is necessary to ensure correct operation under changing
XVolatileBitmap.
Parameter rect
A rectangle, within the bounds of the bitmap, to retrieve the
contens from.
Get a single pixel of the bitmap, returning its color
value.
If the internal data format's pixel are not integer multiples
of bytes (i.e. if one pixel occupies less than a byte - the
case of more than one byte per pixel is not specified), the
color value is returned in the least significant bits of the
single byte returned as the color. The details of the returned
pixel data are to be retrieved from the passed bitmap layout.
Note that the bitmap memory layout might change for volatile
bitmaps.
Parameter bitmapLayout
The memory layout the returned data is in. Note that the color
space returned therein needs to always match the current color
space as would have been returned by getMemoryLayout(). This
is necessary to ensure correct operation under changing
XVolatileBitmap.
Parameter pos
A position, within the bounds of the bitmap, to retrieve the
color from.
