21 SVG Surfaces

Rendering SVG documents

21.1 Overview

The SVG surface is used to render cairo graphics to SVG files and is a multi-page vector surface backend.

21.2 Usage

Function: cairo-svg-surface-create (width-in-points <double>) (height-in-points <double>) [(filename <char>)] ⇒  (ret <cairo-surface-t >)

Creates a SVG surface of the specified size in points to be written to filename. If filename is not given, the output is sent to the current output port.

The SVG surface backend recognizes the following MIME types for the data attached to a surface (see cairo-surface-set-mime-data) when it is used as a source pattern for drawing on this surface: ‘CAIRO_MIME_TYPE_JPEG’, ‘CAIRO_MIME_TYPE_PNG’, ‘CAIRO_MIME_TYPE_URI’. If any of them is specified, the SVG backend emits a href with the content of MIME data instead of a surface snapshot (PNG, Base64-encoded) in the corresponding image tag.

The unofficial MIME type ‘CAIRO_MIME_TYPE_URI’ is examined first. If present, the URI is emitted as is: assuring the correctness of URI is left to the client code.

If ‘CAIRO_MIME_TYPE_URI’ is not present, but ‘CAIRO_MIME_TYPE_JPEG’ or ‘CAIRO_MIME_TYPE_PNG’ is specified, the corresponding data is Base64-encoded and emitted.

filename

a filename for the SVG output (must be writable), ‘#f’ may be used to specify no output. This will generate a SVG surface that may be queried and used as a source, without generating a temporary file.

width-in-points

width of the surface, in points (1 point == 1/72.0 inch)

height-in-points

height of the surface, in points (1 point == 1/72.0 inch)

ret

a pointer to the newly created surface. The caller owns the surface and should call cairo-surface-destroy when done with it. This function always returns a valid pointer, but it will return a pointer to a "nil" surface if an error such as out of memory occurs. You can use cairo-surface-status to check for this.

Since 1.2