cairo-Image-Surfaces {RGtk2.10}R Documentation

Image Surfaces

Description

Rendering to memory buffers

Methods and Functions

cairoImageSurfaceCreate(format, width, height)
cairoImageSurfaceCreateForData(data, format, width, height, stride)
cairoImageSurfaceGetData(surface)
cairoImageSurfaceGetFormat(surface)
cairoImageSurfaceGetWidth(surface)
cairoImageSurfaceGetHeight(surface)
cairoImageSurfaceGetStride(surface)

Detailed Description

Image surfaces provide the ability to render to memory buffers either allocated by cairo or by the calling code. The supported image formats are those defined in CairoFormat.

Enums and Flags

CairoFormat
CairoFormat is used to identify the memory format of image data.

New entries may be added in future versions.

argb32
each pixel is a 32-bit quantity, with alpha in the upper 8 bits, then red, then green, then blue. The 32-bit quantities are stored native-endian. Pre-multiplied alpha is used. (That is, 50 not 0x80ff0000.)
rgb24
each pixel is a 32-bit quantity, with the upper 8 bits unused. Red, Green, and Blue are stored in the remaining 24 bits in that order.
a8
each pixel is a 8-bit quantity holding an alpha value.
a1
each pixel is a 1-bit quantity holding an alpha value. Pixels are packed together into 32-bit quantities. The ordering of the bits matches the endianess of the platform. On a big-endian machine, the first pixel is in the uppermost bit, on a little-endian machine the first pixel is in the least-significant bit.
rgb16-565
This format value is deprecated. It has never been properly implemented in cairo and should not be used by applications. For example, any attempt to create an image surface with a format of CAIRO_FORMAT_RGB16_565 will fail. This format value was added as part of fixing cairo's xlib backend to work with X servers advertising a 16-bit, 565 visual. But as it turned out, adding this format to CairoFormat was not necessary, and was a mistake, (cairo's xlib backend can work fine with 16-bit visuals in the same way it works with BGR visuals without any BGR formats in CairoFormat). (Since 1.2)

Author(s)

Derived by RGtkGen from GTK+ documentation

References

http://www.cairographics.org/manual/cairo-Image-Surfaces.html


[Package RGtk2.10 version 2.10.6 Index]