fltk/FL/Fl_Cairo.H

88 lines
3.0 KiB
C++

//
// Main header file for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2021 by Bill Spitzak and others.
//
// This library is free software. Distribution and use rights are outlined in
// the file "COPYING" which should have been included with this file. If this
// file is missing or damaged, see the license at:
//
// https://www.fltk.org/COPYING.php
//
// Please see the following page on how to report bugs and issues:
//
// https://www.fltk.org/bugs.php
//
/* \file
Handling transparently platform dependent cairo include files
*/
#ifndef FL_CAIRO_H
# define FL_CAIRO_H
# include <FL/fl_config.h> // build configuration
# ifdef FLTK_HAVE_CAIRO
// Cairo is currently supported for the following platforms:
// Win32, Apple Quartz, X11
# include <FL/Fl_Export.H>
# include <cairo.h>
/**
\addtogroup group_cairo
@{
*/
/**
Contains all the necessary info on the current cairo context.
A private internal & unique corresponding object is created to
permit cairo context state handling while keeping it opaque.
For internal use only.
\note Only available when configure has the --enable-cairo or
--enable-cairoext option or one or both of the CMake options
OPTION_CAIRO or OPTION_CAIROEXT is set (ON)
*/
class FL_EXPORT Fl_Cairo_State {
public:
Fl_Cairo_State() : cc_(0), own_cc_(false), autolink_(false), window_(0), gc_(0) {}
// access attributes
cairo_t* cc() const {return cc_;} ///< Gets the current cairo context
bool autolink() const {return autolink_;} ///< Gets the autolink option. See Fl::cairo_autolink_context(bool)
/** Sets the current cairo context.
\p own == \e true (the default) indicates that the cairo context \p c
will be deleted by FLTK internally when another cc is set later.
\p own == \e false indicates cc deletion is handled externally
by the user program.
*/
void cc(cairo_t* c, bool own=true) {
if (cc_ && own_cc_) cairo_destroy(cc_);
cc_=c;
if (!cc_) window_=0;
own_cc_=own;
}
void autolink(bool b); ///< Sets the autolink option, only available with --enable-cairoext
void window(void* w) {window_=w;} ///< Sets the window \p w to keep track on
void* window() const {return window_;} ///< Gets the last window attached to a cc
void gc(void* c) {gc_=c;} ///< Sets the gc \p c to keep track on
void* gc() const {return gc_;} ///< Gets the last gc attached to a cc
private:
cairo_t * cc_; // contains the unique autoupdated cairo context
bool own_cc_; // indicates whether we must delete the cc, useful for internal cleanup
bool autolink_; // false by default, prevents the automatic cairo mapping on fltk windows
// for custom cairo implementations.
void* window_, *gc_; // for keeping track internally of last win+gc treated
};
/** @} */
# endif // FLTK_HAVE_CAIRO
#endif // FL_CAIRO_H