diff options
| -rw-r--r-- | cairomm/surface.cc | 6 | ||||
| -rw-r--r-- | cairomm/surface.h | 23 |
2 files changed, 29 insertions, 0 deletions
diff --git a/cairomm/surface.cc b/cairomm/surface.cc index c5fe9ef..88e72cf 100644 --- a/cairomm/surface.cc +++ b/cairomm/surface.cc @@ -266,6 +266,12 @@ RefPtr<Surface> Surface::create(const RefPtr<Surface> other, Content content, in return RefPtr<Surface>(new Surface(cobject, true /* has reference */)); } +RefPtr<Surface> Surface::create(const RefPtr<Surface>& target, double x, double y, double width, double height) +{ + cairo_surface_t* cobject = cairo_surface_create_for_rectangle(target->cobj(), x, y, width, height); + check_status_and_throw_exception(cairo_surface_status(cobject)); + return RefPtr<Surface>(new Surface(cobject, true /* has reference */)); +} ImageSurface::ImageSurface(cairo_surface_t* cobject, bool has_reference) diff --git a/cairomm/surface.h b/cairomm/surface.h index c5bfb95..8079dc0 100644 --- a/cairomm/surface.h +++ b/cairomm/surface.h @@ -343,6 +343,29 @@ public: */ static RefPtr<Surface> create(const RefPtr<Surface> other, Content content, int width, int height); + /** Create a new surface that is a rectangle within the target surface. All + * operations drawn to this surface are then clipped and translated onto the + * target surface. Nothing drawn via this sub-surface outside of its bounds is + * drawn onto the target surface, making this a useful method for passing + * constrained child surfaces to library routines that draw directly onto the + * parent surface, i.e. with no further backend allocations, double buffering + * or copies. + * + * @Note The semantics of subsurfaces have not been finalized yet unless the + * rectangle is in full device units, is contained within the extents of the + * target surface, and the target or subsurface's device transforms are not + * changed. + * + * @param target an existing surface for which the sub-surface will point to + * @param x the x-origin of the sub-surface from the top-left of the target surface (in device-space units) + * @param y the y-origin of the sub-surface from the top-left of the target surface (in device-space units) + * @param width width of the sub-surface (in device-space units) + * @param height height of the sub-surface (in device-space units) + * + * @since 1.10 + */ + static RefPtr<Surface> create(const RefPtr<Surface>& target, double x, double y, double width, double height); + protected: /** The underlying C cairo surface type that is wrapped by this Surface */ |