Add the Wayland platform to FLTK 1.4

1 files changed, 158 insertions, 0 deletions

diff --git a/src/drivers/Wayland/Fl_Wayland_Graphics_Driver.H b/src/drivers/Wayland/Fl_Wayland_Graphics_Driver.H
new file mode 100644
index 000000000..19991c531
--- /dev/null
+++ b/src/drivers/Wayland/Fl_Wayland_Graphics_Driver.H
@@ -0,0 +1,158 @@
+//
+// Definition of class Fl_Wayland_Graphics_Driver.
+//
+// Copyright 2021-2022 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 Fl_Wayland_Graphics_Driver.H
+ \brief Definition of Wayland graphics driver.
+ */
+
+#ifndef FL_WAYLAND_GRAPHICS_DRIVER_H
+#define FL_WAYLAND_GRAPHICS_DRIVER_H
+
+
+/* Implementation note about buffers FLTK uses to support display graphics under Wayland.
+ 
+ Each window is associated to an FLTK-defined object of type struct wld_window
+ containing itself an FLTK-defined struct fl_wld_buffer object holding all graphics data.
+ Among members of this latter structure are:
+ - struct wl_buffer wl_buffer
+ is a Wayland-defined type for a graphics buffer able to be attached to a wl_surface;
+ - void *data
+ points to the beginning of the memory zone where wl_buffer stores its graphics data;
+ - unsigned char *draw_buffer
+ contains a graphics buffer to which all Cairo drawings are directed;
+ draw_buffer and data both have the same organization called CAIRO_FORMAT_ARGB32 in Cairo parlance
+ and WL_SHM_FORMAT_ARGB8888 in Wayland parlance which means BGRA byte order.
+ - int width
+ gives the pixel width of the graphics buffer;
+ - int stride
+ gives the stride of this buffer;
+ - size_t data_size
+ gives the total buffer size in bytes (thus, data_size / stride gives the buffer height);
+ - bool draw_buffer_needs_commit
+ is TRUE when draw_buffer has been modified and needs being committed for display, and
+ FALSE after having been committed but before having been modified;
+ - struct wl_callback *cb
+ is used to synchronize drawing with the compositor during progressive drawing.
+ 
+ When a graphics scene is to be committed, the data_size bytes of draw_buffer are copied by memcpy()
+ starting at data, and wl_buffer is attached to the wl_surface which is committed for display
+ by wl_surface_commit(). Finally, draw_buffer_needs_commit is set to FALSE.
+ 
+ All drawing functions have Cairo write to draw_buffer and turn draw_buffer_needs_commit to TRUE.
+*/
+
+
+#include "../Cairo/Fl_Cairo_Graphics_Driver.H"
+#include <cairo/cairo.h>
+#include <stdint.h> // for uint32_t
+typedef struct _PangoLayout  PangoLayout;
+
+struct fl_wld_buffer {
+  struct wl_buffer *wl_buffer;
+  void *data;
+  size_t data_size; // of wl_buffer and draw_buffer
+  int stride;
+  int width;
+  unsigned char *draw_buffer;
+  struct wl_callback *cb;
+  bool draw_buffer_needs_commit;
+  cairo_t *cairo_;
+  PangoLayout *pango_layout_;
+};
+struct wld_window;
+
+class FL_EXPORT Fl_Wayland_Graphics_Driver : public Fl_Cairo_Graphics_Driver {
+private:
+  struct fl_wld_buffer *buffer_;
+  PangoLayout *dummy_pango_layout_; // used to measure text width before showing a window
+  int linestyle_;
+  void draw_cached_pattern_(Fl_Image *img, cairo_pattern_t *pat, int X, int Y, int W, int H, int cx, int cy);
+public:
+  Fl_Wayland_Graphics_Driver();
+  ~Fl_Wayland_Graphics_Driver();
+  static const uint32_t wld_format;
+  static const cairo_format_t cairo_format;
+  void activate(struct fl_wld_buffer *buffer, float scale);
+  void font(Fl_Font fnum, Fl_Fontsize s);
+  Fl_Font font() { return Fl_Graphics_Driver::font(); }
+  void draw(const char* s, int nBytes, int x, int y) { draw(s, nBytes, float(x), float(y)); }
+  void draw(const char* s, int nBytes, float x, float y);
+  void draw(int angle, const char *str, int n, int x, int y);
+  void rtl_draw(const char* str, int n, int x, int y);
+  int height();
+  int descent();
+  double width(const char *str, int n);
+  double width(unsigned c);
+  void text_extents(const char* txt, int n, int& dx, int& dy, int& w, int& h);
+  int not_clipped(int x, int y, int w, int h);
+  int clip_box(int x, int y, int w, int h, int &X, int &Y, int &W, int &H);
+  void restore_clip();
+  void clip_region(Fl_Region r);
+  void line_style(int style, int width=0, char* dashes=0);
+  Fl_Region XRectangleRegion(int x, int y, int w, int h);
+  void add_rectangle_to_region(Fl_Region r, int X, int Y, int W, int H);
+  void XDestroyRegion(Fl_Region r);
+  void set_color(Fl_Color i, unsigned c);
+  Fl_Font set_fonts(const char* pattern_name);
+  const char *font_name(int num);
+  void font_name(int num, const char *name);
+  const char* get_font_name(Fl_Font fnum, int* ap);
+  int get_font_sizes(Fl_Font fnum, int*& sizep);
+  void point(int x, int y);
+  void copy_offscreen(int x, int y, int w, int h, Fl_Offscreen osrc, int srcx, int srcy);
+  void draw_image(const uchar *data, int ix, int iy, int iw, int ih, int D, int LD);
+  void curve(double x, double y, double x1, double y1, double x2, double y2, double x3, double y3);
+  void begin_points();
+  void end_points();
+  void transformed_vertex(double x, double y);
+  void draw_rgb(Fl_RGB_Image *rgb,int XP, int YP, int WP, int HP, int cx, int cy);
+  void cache(Fl_RGB_Image *rgb);
+  void uncache(Fl_RGB_Image *img, fl_uintptr_t &id_, fl_uintptr_t &mask_);
+  void draw_bitmap(Fl_Bitmap *bm,int XP, int YP, int WP, int HP, int cx, int cy);
+  void cache(Fl_Bitmap *img);
+  void delete_bitmask(Fl_Bitmask bm);
+  void cache(Fl_Pixmap *pxm);
+  void draw_pixmap(Fl_Pixmap *rgb,int XP, int YP, int WP, int HP, int cx, int cy);
+  void uncache_pixmap(fl_uintptr_t p);
+  void overlay_rect(int x, int y, int w , int h);
+  static void init_built_in_fonts();
+  static struct fl_wld_buffer *create_shm_buffer(int width, int height);
+  static void buffer_release(struct wld_window *window);
+  static void buffer_commit(struct wld_window *window);
+  static void cairo_init(struct fl_wld_buffer *buffer, int width, int height, int stride, cairo_format_t format);
+  void line(int x1, int y1, int x2, int y2);
+  void line(int x1, int y1, int x2, int y2, int x3, int y3);
+  void xyline(int x, int y, int x1);
+  void xyline(int x, int y, int x1, int y2);
+  void xyline(int x, int y, int x1, int y2, int x3);
+  void yxline(int x, int y, int y1);
+  void yxline(int x, int y, int y1, int x2);
+  void yxline(int x, int y, int y1, int x2, int y3);
+  void loop(int x0, int y0, int x1, int y1, int x2, int y2);
+  void loop(int x0, int y0, int x1, int y1, int x2, int y2, int x3, int y3);
+  void rect(int x, int y, int w, int h);
+  void rectf(int x, int y, int w, int h);
+  void polygon(int x0, int y0, int x1, int y1, int x2, int y2);
+  void polygon(int x0, int y0, int x1, int y1, int x2, int y2, int x3, int y3);
+  void end_loop();
+  void end_line();
+  void end_polygon();
+  void set_spot(int font, int height, int x, int y, int w, int h, Fl_Window *win);
+  void reset_spot();
+};
+
+#endif // FL_WAYLAND_GRAPHICS_DRIVER_H