fltk/FL/x.H
Albrecht Schlosser 0c70362e63 Fix offscreen drawing under X11 (STR 3384)
- fix undefined 'GC' if no window has been shown/drawn yet
- may still need to call fl_open_display() prior to offscreen-drawing
- improve documentation, add example code
2020-11-03 12:02:54 +01:00

186 lines
6.4 KiB
C++

//
// "$Id$"
//
// X11 header file for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2012 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:
//
// http://www.fltk.org/COPYING.php
//
// Please report all bugs and problems on the following page:
//
// http://www.fltk.org/str.php
//
// These are internal fltk symbols that are necessary or useful for
// calling Xlib. You should include this file if (and ONLY if) you
// need to call Xlib directly. These symbols may not exist on non-X
// systems.
#if !defined(Fl_X_H) && !defined(FL_DOXYGEN)
# define Fl_X_H
# include "Enumerations.H"
# ifdef WIN32
# include "win32.H"
# elif defined(__APPLE__)
# include "mac.H"
# else
# if defined(_ABIN32) || defined(_ABI64) // fix for broken SGI Irix X .h files
# pragma set woff 3322
# endif
# include <X11/Xlib.h>
# include <X11/Xutil.h>
# if defined(_ABIN32) || defined(_ABI64)
# pragma reset woff 3322
# endif
# include <X11/Xatom.h>
# include "Fl_Window.H"
// Mirror X definition of Region to Fl_Region, for portability...
typedef Region Fl_Region;
FL_EXPORT void fl_open_display();
FL_EXPORT void fl_open_display(Display*);
FL_EXPORT void fl_close_display();
// constant info about the X server connection:
extern FL_EXPORT Display *fl_display;
extern FL_EXPORT int fl_screen;
extern FL_EXPORT XVisualInfo *fl_visual;
extern FL_EXPORT Colormap fl_colormap;
// drawing functions:
extern FL_EXPORT GC fl_gc;
extern FL_EXPORT Window fl_window;
FL_EXPORT ulong fl_xpixel(Fl_Color i);
FL_EXPORT ulong fl_xpixel(uchar r, uchar g, uchar b);
FL_EXPORT void fl_clip_region(Fl_Region);
FL_EXPORT Fl_Region fl_clip_region();
// feed events into fltk:
FL_EXPORT int fl_handle(const XEvent&);
// you can use these in Fl::add_handler() to look at events:
extern FL_EXPORT const XEvent* fl_xevent;
extern FL_EXPORT ulong fl_event_time;
// off-screen pixmaps: create, destroy, draw into, copy to window:
typedef ulong Fl_Offscreen;
# define fl_create_offscreen(w,h) XCreatePixmap(fl_display, RootWindow(fl_display, fl_screen), w, h, fl_visual->depth)
# define fl_create_offscreen_with_alpha(w,h) XCreatePixmap(fl_display, RootWindow(fl_display, fl_screen), w, h, 32)
// begin/end are macros that save the old state in local variables:
# define fl_begin_offscreen(pixmap) \
Window _sw=fl_window; fl_window=pixmap; \
GC _sgc = fl_gc; if (!_sgc) fl_gc = XCreateGC(fl_display, pixmap, 0, 0); \
Fl_Surface_Device *_ss = Fl_Surface_Device::surface(); Fl_Display_Device::display_device()->set_current(); \
fl_push_no_clip()
# define fl_end_offscreen() \
fl_pop_clip(); fl_window = _sw; _ss->set_current(); \
if (!_sgc) XFreeGC(fl_display, fl_gc); fl_gc = _sgc
extern FL_EXPORT void fl_copy_offscreen(int x, int y, int w, int h, Fl_Offscreen pixmap, int srcx, int srcy);
# define fl_delete_offscreen(pixmap) XFreePixmap(fl_display, pixmap)
// Bitmap masks
typedef ulong Fl_Bitmask;
extern FL_EXPORT Fl_Bitmask fl_create_bitmask(int w, int h, const uchar *data);
extern FL_EXPORT Fl_Bitmask fl_create_alphamask(int w, int h, int d, int ld, const uchar *data);
extern FL_EXPORT void fl_delete_bitmask(Fl_Bitmask bm);
#if defined(FL_LIBRARY) || defined(FL_INTERNALS)
extern FL_EXPORT Window fl_message_window;
extern FL_EXPORT void *fl_xftfont;
FL_EXPORT Fl_Region XRectangleRegion(int x, int y, int w, int h); // in fl_rect.cxx
// access to core fonts:
// This class provides a "smart pointer" that returns a pointer to an XFontStruct.
// The global variable fl_xfont can be called wherever a bitmap "core" font is
// needed, e.g. when rendering to a GL context under X11.
// With Xlib / X11 fonts, fl_xfont will return the current selected font.
// With XFT / X11 fonts, fl_xfont will attempt to return the bitmap "core" font most
// similar to (usually the same as) the current XFT font.
class Fl_XFont_On_Demand
{
public:
Fl_XFont_On_Demand(XFontStruct* p = NULL) : ptr(p) { }
Fl_XFont_On_Demand& operator=(const Fl_XFont_On_Demand& x)
{ ptr = x.ptr; return *this; }
Fl_XFont_On_Demand& operator=(XFontStruct* p)
{ ptr = p; return *this; }
XFontStruct* value();
operator XFontStruct*() { return value(); }
XFontStruct& operator*() { return *value(); }
XFontStruct* operator->() { return value(); }
bool operator==(const Fl_XFont_On_Demand& x) { return ptr == x.ptr; }
bool operator!=(const Fl_XFont_On_Demand& x) { return ptr != x.ptr; }
private:
XFontStruct *ptr;
};
extern FL_EXPORT Fl_XFont_On_Demand fl_xfont;
extern FL_EXPORT XFontStruct* fl_X_core_font();
// this object contains all X-specific stuff about a window:
// Warning: this object is highly subject to change!
// FL_LIBRARY or FL_INTERNALS must be defined to access this class.
class FL_EXPORT Fl_X {
public:
Window xid;
Window other_xid;
Fl_Window *w;
Fl_Region region;
Fl_X *next;
char wait_for_expose;
char backbuffer_bad; // used for XDBE
static Fl_X* first;
static Fl_X* i(const Fl_Window* wi) {return wi->i;}
void setwindow(Fl_Window* wi) {w=wi; wi->i=this;}
void sendxjunk();
static void set_default_icons(const Fl_RGB_Image*[], int);
void set_icons();
int set_cursor(Fl_Cursor);
int set_cursor(const Fl_RGB_Image*, int, int);
static void make_xid(Fl_Window*,XVisualInfo* =fl_visual, Colormap=fl_colormap);
static Fl_X* set_xid(Fl_Window*, Window);
// kludges to get around protection:
void flush() {w->flush();}
static void x(Fl_Window* wi, int X) {wi->x(X);}
static void y(Fl_Window* wi, int Y) {wi->y(Y);}
static int ewmh_supported();
static int xrender_supported();
static void activate_window(Window w);
};
extern FL_EXPORT char fl_override_redirect; // hack into Fl_X::make_xid()
extern FL_EXPORT int fl_background_pixel; // hack into Fl_X::make_xid()
inline Window fl_xid(const Fl_Window* w) { Fl_X *xTemp = Fl_X::i(w); return xTemp ? xTemp->xid : 0; }
#else
extern FL_EXPORT Window fl_xid_(const Fl_Window* w);
#define fl_xid(w) fl_xid_(w)
#endif // FL_LIBRARY || FL_INTERNALS
FL_EXPORT Fl_Window* fl_find(Window xid);
// Dummy function to register a function for opening files via the window manager...
inline void fl_open_callback(void (*)(const char *)) {}
extern FL_EXPORT int fl_parse_color(const char* p, uchar& r, uchar& g, uchar& b);
# endif
#endif
//
// End of "$Id$".
//