Re: [Qemu-devel] [PULL 4/5] gtk: add opengl support, using egl

[Paolo Bonzini <pbonzini@redhat.com>]

On 29/05/2015 12:07, Gerd Hoffmann wrote:
> This adds opengl rendering support to the gtk ui, using egl.
> It's off by default for now, use 'qemu -display gtk,gl=on'
> to play with this.
> 
> Note that gtk got native opengl support with release 3.16.
> There most likely will be a separate implementation for 3.16+,
> using the native gtk opengl support.  This patch covers older
> versions (and for the time being 3.16 too, hopefully without
> rendering quirks).
> 
> Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

This unfortunately breaks "-device help" if you do not have an X11
connection.  gtk_init exits the program.

Paolo

> ---
>  include/ui/console.h |   2 +-
>  include/ui/gtk.h     |  23 +++++++++
>  ui/Makefile.objs     |   3 ++
>  ui/gtk-egl.c         | 141 +++++++++++++++++++++++++++++++++++++++++++++++++++
>  ui/gtk.c             |  90 ++++++++++++++++++++++++++------
>  vl.c                 |  11 +++-
>  6 files changed, 253 insertions(+), 17 deletions(-)
>  create mode 100644 ui/gtk-egl.c
> 
> diff --git a/include/ui/console.h b/include/ui/console.h
> index 383dec2..6f7550e 100644
> --- a/include/ui/console.h
> +++ b/include/ui/console.h
> @@ -393,7 +393,7 @@ void curses_display_init(DisplayState *ds, int full_screen);
>  int index_from_key(const char *key);
>  
>  /* gtk.c */
> -void early_gtk_display_init(void);
> +void early_gtk_display_init(int opengl);
>  void gtk_display_init(DisplayState *ds, bool full_screen, bool grab_on_hover);
>  
>  #endif
> diff --git a/include/ui/gtk.h b/include/ui/gtk.h
> index b750845..ee6dffd 100644
> --- a/include/ui/gtk.h
> +++ b/include/ui/gtk.h
> @@ -22,6 +22,10 @@
>  #include <X11/XKBlib.h>
>  #endif
>  
> +#if defined(CONFIG_OPENGL)
> +#include "ui/egl-helpers.h"
> +#endif
> +
>  /* Compatibility define to let us build on both Gtk2 and Gtk3 */
>  #if GTK_CHECK_VERSION(3, 0, 0)
>  static inline void gdk_drawable_get_size(GdkWindow *w, gint *ww, gint *wh)
> @@ -41,6 +45,12 @@ typedef struct VirtualGfxConsole {
>      cairo_surface_t *surface;
>      double scale_x;
>      double scale_y;
> +#if defined(CONFIG_OPENGL)
> +    ConsoleGLState *gls;
> +    EGLContext ectx;
> +    EGLSurface esurface;
> +    int glupdates;
> +#endif
>  } VirtualGfxConsole;
>  
>  #if defined(CONFIG_VTE)
> @@ -73,4 +83,17 @@ typedef struct VirtualConsole {
>      };
>  } VirtualConsole;
>  
> +/* ui/gtk.c */
> +void gd_update_windowsize(VirtualConsole *vc);
> +
> +/* ui/gtk-egl.c */
> +void gd_egl_init(VirtualConsole *vc);
> +void gd_egl_draw(VirtualConsole *vc);
> +void gd_egl_update(DisplayChangeListener *dcl,
> +                   int x, int y, int w, int h);
> +void gd_egl_refresh(DisplayChangeListener *dcl);
> +void gd_egl_switch(DisplayChangeListener *dcl,
> +                   DisplaySurface *surface);
> +void gtk_egl_init(void);
> +
>  #endif /* UI_GTK_H */
> diff --git a/ui/Makefile.objs b/ui/Makefile.objs
> index 5c46870..023914c 100644
> --- a/ui/Makefile.objs
> +++ b/ui/Makefile.objs
> @@ -31,13 +31,16 @@ ifeq ($(CONFIG_OPENGL),y)
>  common-obj-y += shader.o
>  common-obj-y += console-gl.o
>  common-obj-y += egl-helpers.o
> +common-obj-$(CONFIG_GTK) += gtk-egl.o
>  endif
>  
>  gtk.o-cflags := $(GTK_CFLAGS) $(VTE_CFLAGS)
> +gtk-egl.o-cflags := $(GTK_CFLAGS) $(VTE_CFLAGS) $(OPENGL_CFLAGS)
>  shader.o-cflags += $(OPENGL_CFLAGS)
>  console-gl.o-cflags += $(OPENGL_CFLAGS)
>  egl-helpers.o-cflags += $(OPENGL_CFLAGS)
>  
> +gtk-egl.o-libs += $(OPENGL_LIBS)
>  shader.o-libs += $(OPENGL_LIBS)
>  console-gl.o-libs += $(OPENGL_LIBS)
>  egl-helpers.o-libs += $(OPENGL_LIBS)
> diff --git a/ui/gtk-egl.c b/ui/gtk-egl.c
> new file mode 100644
> index 0000000..15b41f2
> --- /dev/null
> +++ b/ui/gtk-egl.c
> @@ -0,0 +1,141 @@
> +/*
> + * GTK UI -- egl opengl code.
> + *
> + * Note that gtk 3.16+ (released 2015-03-23) has a GtkGLArea widget,
> + * which is GtkDrawingArea like widget with opengl rendering support.
> + *
> + * This code handles opengl support on older gtk versions, using egl
> + * to get a opengl context for the X11 window.
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> + * See the COPYING file in the top-level directory.
> + */
> +
> +#include "qemu-common.h"
> +
> +#include "trace.h"
> +
> +#include "ui/console.h"
> +#include "ui/gtk.h"
> +#include "ui/egl-helpers.h"
> +
> +#include "sysemu/sysemu.h"
> +
> +/** DisplayState Callbacks (opengl version) **/
> +
> +void gd_egl_init(VirtualConsole *vc)
> +{
> +    GdkWindow *gdk_window = gtk_widget_get_window(vc->gfx.drawing_area);
> +    if (!gdk_window) {
> +        return;
> +    }
> +
> +#if GTK_CHECK_VERSION(3, 0, 0)
> +    Window x11_window = gdk_x11_window_get_xid(gdk_window);
> +#else
> +    Window x11_window = gdk_x11_drawable_get_xid(gdk_window);
> +#endif
> +    if (!x11_window) {
> +        return;
> +    }
> +
> +    vc->gfx.ectx = qemu_egl_init_ctx();
> +    vc->gfx.esurface = qemu_egl_init_surface_x11(vc->gfx.ectx, x11_window);
> +
> +    assert(vc->gfx.esurface);
> +}
> +
> +void gd_egl_draw(VirtualConsole *vc)
> +{
> +    GdkWindow *window;
> +    int ww, wh;
> +
> +    if (!vc->gfx.gls || !vc->gfx.ds) {
> +        return;
> +    }
> +
> +    eglMakeCurrent(qemu_egl_display, vc->gfx.esurface,
> +                   vc->gfx.esurface, vc->gfx.ectx);
> +
> +    window = gtk_widget_get_window(vc->gfx.drawing_area);
> +    gdk_drawable_get_size(window, &ww, &wh);
> +    surface_gl_setup_viewport(vc->gfx.gls, vc->gfx.ds, ww, wh);
> +    surface_gl_render_texture(vc->gfx.gls, vc->gfx.ds);
> +
> +    eglSwapBuffers(qemu_egl_display, vc->gfx.esurface);
> +}
> +
> +void gd_egl_update(DisplayChangeListener *dcl,
> +                   int x, int y, int w, int h)
> +{
> +    VirtualConsole *vc = container_of(dcl, VirtualConsole, gfx.dcl);
> +
> +    if (!vc->gfx.gls || !vc->gfx.ds) {
> +        return;
> +    }
> +
> +    eglMakeCurrent(qemu_egl_display, vc->gfx.esurface,
> +                   vc->gfx.esurface, vc->gfx.ectx);
> +    surface_gl_update_texture(vc->gfx.gls, vc->gfx.ds, x, y, w, h);
> +    vc->gfx.glupdates++;
> +}
> +
> +void gd_egl_refresh(DisplayChangeListener *dcl)
> +{
> +    VirtualConsole *vc = container_of(dcl, VirtualConsole, gfx.dcl);
> +
> +    if (!vc->gfx.esurface) {
> +        gd_egl_init(vc);
> +        if (!vc->gfx.esurface) {
> +            return;
> +        }
> +        vc->gfx.gls = console_gl_init_context();
> +        if (vc->gfx.ds) {
> +            surface_gl_create_texture(vc->gfx.gls, vc->gfx.ds);
> +        }
> +    }
> +
> +    graphic_hw_update(dcl->con);
> +
> +    if (vc->gfx.glupdates) {
> +        vc->gfx.glupdates = 0;
> +        gd_egl_draw(vc);
> +    }
> +}
> +
> +void gd_egl_switch(DisplayChangeListener *dcl,
> +                   DisplaySurface *surface)
> +{
> +    VirtualConsole *vc = container_of(dcl, VirtualConsole, gfx.dcl);
> +    bool resized = true;
> +
> +    trace_gd_switch(vc->label, surface_width(surface), surface_height(surface));
> +
> +    if (vc->gfx.ds &&
> +        surface_width(vc->gfx.ds) == surface_width(surface) &&
> +        surface_height(vc->gfx.ds) == surface_height(surface)) {
> +        resized = false;
> +    }
> +
> +    surface_gl_destroy_texture(vc->gfx.gls, vc->gfx.ds);
> +    vc->gfx.ds = surface;
> +    if (vc->gfx.gls) {
> +        surface_gl_create_texture(vc->gfx.gls, vc->gfx.ds);
> +    }
> +
> +    if (resized) {
> +        gd_update_windowsize(vc);
> +    }
> +}
> +
> +void gtk_egl_init(void)
> +{
> +    GdkDisplay *gdk_display = gdk_display_get_default();
> +    Display *x11_display = gdk_x11_display_get_xdisplay(gdk_display);
> +
> +    if (qemu_egl_init_dpy(x11_display, false, false) < 0) {
> +        return;
> +    }
> +
> +    display_opengl = 1;
> +}
> diff --git a/ui/gtk.c b/ui/gtk.c
> index c58028f..2477e37 100644
> --- a/ui/gtk.c
> +++ b/ui/gtk.c
> @@ -339,7 +339,7 @@ static void gd_update_geometry_hints(VirtualConsole *vc)
>      gtk_window_set_geometry_hints(geo_window, geo_widget, &geo, mask);
>  }
>  
> -static void gd_update_windowsize(VirtualConsole *vc)
> +void gd_update_windowsize(VirtualConsole *vc)
>  {
>      GtkDisplayState *s = vc->s;
>  
> @@ -581,6 +581,33 @@ static void gd_switch(DisplayChangeListener *dcl,
>      }
>  }
>  
> +static const DisplayChangeListenerOps dcl_ops = {
> +    .dpy_name             = "gtk",
> +    .dpy_gfx_update       = gd_update,
> +    .dpy_gfx_switch       = gd_switch,
> +    .dpy_gfx_check_format = qemu_pixman_check_format,
> +    .dpy_refresh          = gd_refresh,
> +    .dpy_mouse_set        = gd_mouse_set,
> +    .dpy_cursor_define    = gd_cursor_define,
> +};
> +
> +
> +#if defined(CONFIG_OPENGL)
> +
> +/** DisplayState Callbacks (opengl version) **/
> +
> +static const DisplayChangeListenerOps dcl_egl_ops = {
> +    .dpy_name             = "gtk-egl",
> +    .dpy_gfx_update       = gd_egl_update,
> +    .dpy_gfx_switch       = gd_egl_switch,
> +    .dpy_gfx_check_format = console_gl_check_format,
> +    .dpy_refresh          = gd_egl_refresh,
> +    .dpy_mouse_set        = gd_mouse_set,
> +    .dpy_cursor_define    = gd_cursor_define,
> +};
> +
> +#endif
> +
>  /** QEMU Events **/
>  
>  static void gd_change_runstate(void *opaque, int running, RunState state)
> @@ -637,6 +664,13 @@ static gboolean gd_draw_event(GtkWidget *widget, cairo_t *cr, void *opaque)
>      int ww, wh;
>      int fbw, fbh;
>  
> +#if defined(CONFIG_OPENGL)
> +    if (vc->gfx.gls) {
> +        gd_egl_draw(vc);
> +        return TRUE;
> +    }
> +#endif
> +
>      if (!gtk_widget_get_realized(widget)) {
>          return FALSE;
>      }
> @@ -1676,16 +1710,6 @@ static GtkWidget *gd_create_menu_machine(GtkDisplayState *s)
>      return machine_menu;
>  }
>  
> -static const DisplayChangeListenerOps dcl_ops = {
> -    .dpy_name             = "gtk",
> -    .dpy_gfx_update       = gd_update,
> -    .dpy_gfx_switch       = gd_switch,
> -    .dpy_gfx_check_format = qemu_pixman_check_format,
> -    .dpy_refresh          = gd_refresh,
> -    .dpy_mouse_set        = gd_mouse_set,
> -    .dpy_cursor_define    = gd_cursor_define,
> -};
> -
>  static GSList *gd_vc_gfx_init(GtkDisplayState *s, VirtualConsole *vc,
>                                QemuConsole *con, int idx,
>                                GSList *group, GtkWidget *view_menu)
> @@ -1713,7 +1737,29 @@ static GSList *gd_vc_gfx_init(GtkDisplayState *s, VirtualConsole *vc,
>      gtk_notebook_append_page(GTK_NOTEBOOK(s->notebook),
>                               vc->tab_item, gtk_label_new(vc->label));
>  
> -    vc->gfx.dcl.ops = &dcl_ops;
> +#if defined(CONFIG_OPENGL)
> +    if (display_opengl) {
> +        /*
> +         * gtk_widget_set_double_buffered() was deprecated in 3.14.
> +         * It is required for opengl rendering on X11 though.  A
> +         * proper replacement (native opengl support) is only
> +         * available in 3.16+.  Silence the warning if possible.
> +         */
> +#ifdef CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE
> +#pragma GCC diagnostic push
> +#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
> +#endif
> +        gtk_widget_set_double_buffered(vc->gfx.drawing_area, FALSE);
> +#ifdef CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE
> +#pragma GCC diagnostic pop
> +#endif
> +        vc->gfx.dcl.ops = &dcl_egl_ops;
> +    } else
> +#endif
> +    {
> +        vc->gfx.dcl.ops = &dcl_ops;
> +    }
> +
>      vc->gfx.dcl.con = con;
>      register_displaychangelistener(&vc->gfx.dcl);
>  
> @@ -1876,8 +1922,6 @@ void gtk_display_init(DisplayState *ds, bool full_screen, bool grab_on_hover)
>      GtkDisplayState *s = g_malloc0(sizeof(*s));
>      char *filename;
>  
> -    gtk_init(NULL, NULL);
> -
>      s->window = gtk_window_new(GTK_WINDOW_TOPLEVEL);
>  #if GTK_CHECK_VERSION(3, 2, 0)
>      s->vbox = gtk_box_new(GTK_ORIENTATION_VERTICAL, 0);
> @@ -1954,8 +1998,24 @@ void gtk_display_init(DisplayState *ds, bool full_screen, bool grab_on_hover)
>      gd_set_keycode_type(s);
>  }
>  
> -void early_gtk_display_init(void)
> +void early_gtk_display_init(int opengl)
>  {
> +    gtk_init(NULL, NULL);
> +
> +    switch (opengl) {
> +    case -1: /* default */
> +    case 0:  /* off */
> +        break;
> +    case 1: /* on */
> +#if defined(CONFIG_OPENGL)
> +        gtk_egl_init();
> +#endif
> +        break;
> +    default:
> +        g_assert_not_reached();
> +        break;
> +    }
> +
>  #if defined(CONFIG_VTE)
>      register_vc_handler(gd_vc_handler);
>  #endif
> diff --git a/vl.c b/vl.c
> index 15bccc4..26b1e7e 100644
> --- a/vl.c
> +++ b/vl.c
> @@ -2047,6 +2047,15 @@ static DisplayType select_display(const char *p)
>                  } else {
>                      goto invalid_gtk_args;
>                  }
> +            } else if (strstart(opts, ",gl=", &nextopt)) {
> +                opts = nextopt;
> +                if (strstart(opts, "on", &nextopt)) {
> +                    request_opengl = 1;
> +                } else if (strstart(opts, "off", &nextopt)) {
> +                    request_opengl = 0;
> +                } else {
> +                    goto invalid_gtk_args;
> +                }
>              } else {
>              invalid_gtk_args:
>                  fprintf(stderr, "Invalid GTK option string: %s\n", p);
> @@ -4012,7 +4021,7 @@ int main(int argc, char **argv, char **envp)
>  
>  #if defined(CONFIG_GTK)
>      if (display_type == DT_GTK) {
> -        early_gtk_display_init();
> +        early_gtk_display_init(request_opengl);
>      }
>  #endif
>  #if defined(CONFIG_SDL)
>