Module org.freedesktop.cairo

Package org.freedesktop.cairo

Interface RasterSourceAcquireFunc

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface RasterSourceAcquireFunc

RasterSourceAcquireFunc is the type of function which is called when a pattern is being rendered from. It should create a surface that provides the pixel data for the region of interest as defined by extents, though the surface itself does not have to be limited to that area. For convenience the surface should probably be of image type, created with Surface.createSimilarImage(Surface, Format, int, int) for the target (which enables the number of copies to be reduced during transfer to the device). Another option, might be to return a similar surface to the target for explicit handling by the application of a set of cached sources on the device. The region of sample data provided should be defined using Surface.setDeviceOffset(double, double) to specify the top-left corner of the sample data (along with width and height of the surface).

Since:

1.12

Method Summary

Modifier and Type	Method	Description
Surface	acquire(RasterSource pattern, Surface target, RectangleInt extents)	Called when a pattern is being rendered from.
default MemorySegment	toCallback(Arena arena)	Generates an upcall stub, a C function pointer that will call upcall(java.lang.foreign.MemorySegment, java.lang.foreign.MemorySegment, java.lang.foreign.MemorySegment, java.lang.foreign.MemorySegment).
default MemorySegment	upcall(MemorySegment pattern, MemorySegment callbackData, MemorySegment target, MemorySegment extents)	The callback that is executed by native code.

Method Details

acquire

Surface acquire(RasterSource pattern,
 Surface target,
 RectangleInt extents)

Called when a pattern is being rendered from. It should create a surface that provides the pixel data for the region of interest as defined by extents, though the surface itself does not have to be limited to that area. For convenience the surface should probably be of image type, created with Surface.createSimilarImage(Surface, Format, int, int) for the target (which enables the number of copies to be reduced during transfer to the device). Another option, might be to return a similar surface to the target for explicit handling by the application of a set of cached sources on the device. The region of sample data provided should be defined using Surface.setDeviceOffset(double, double) to specify the top-left corner of the sample data (along with width and height of the surface).

Parameters:

pattern - the pattern being rendered from

target - the rendering target surface

extents - rectangular region of interest in pixels in sample space

Returns:

a Surface

Since:

1.12

upcall

default MemorySegment upcall(MemorySegment pattern,
 MemorySegment callbackData,
 MemorySegment target,
 MemorySegment extents)

The callback that is executed by native code. This method marshals the parameters and calls acquire(RasterSource, Surface, RectangleInt).

Parameters:

pattern - the pattern being rendered from

callbackData - ignored

target - the rendering target surface

extents - rectangular region of interest in pixels in sample space

Returns:

a Surface

Since:

1.12

toCallback

default MemorySegment toCallback(Arena arena)

Generates an upcall stub, a C function pointer that will call upcall(java.lang.foreign.MemorySegment, java.lang.foreign.MemorySegment, java.lang.foreign.MemorySegment, java.lang.foreign.MemorySegment).

Parameters:

arena - the arena in which the upcall stub will be allocated

Returns:

the function pointer of the upcall stub

Since:

1.12