[3/4] sdl2: add support for display rendering using opengl.

diff --git a/include/ui/console.h b/include/ui/console.h
index 5cb169c..7496dee 100644
--- a/include/ui/console.h
+++ b/include/ui/console.h
@@ -344,6 +344,7 @@  void surface_gl_setup_viewport(DisplaySurface *surface,
 #endif
 
 /* sdl.c */
+void sdl_display_early_init(int opengl);
 void sdl_display_init(DisplayState *ds, int full_screen, int no_frame);
 
 /* cocoa.m */
diff --git a/include/ui/sdl2.h b/include/ui/sdl2.h
index f56c596..5c962da 100644
--- a/include/ui/sdl2.h
+++ b/include/ui/sdl2.h
@@ -11,6 +11,9 @@  struct sdl2_console {
     int last_vm_running; /* per console for caption reasons */
     int x, y;
     int hidden;
+    int opengl;
+    int updates;
+    SDL_GLContext winctx;
 };
 
 void sdl2_window_create(struct sdl2_console *scon);
@@ -29,4 +32,11 @@  void sdl2_2d_switch(DisplayChangeListener *dcl,
 void sdl2_2d_refresh(DisplayChangeListener *dcl);
 void sdl2_2d_redraw(struct sdl2_console *scon);
 
+void sdl2_gl_update(DisplayChangeListener *dcl,
+                    int x, int y, int w, int h);
+void sdl2_gl_switch(DisplayChangeListener *dcl,
+                    DisplaySurface *new_surface);
+void sdl2_gl_refresh(DisplayChangeListener *dcl);
+void sdl2_gl_redraw(struct sdl2_console *scon);
+
 #endif /* SDL2_H */
diff --git a/ui/Makefile.objs b/ui/Makefile.objs
index 3173778..c1f4299 100644
--- a/ui/Makefile.objs
+++ b/ui/Makefile.objs
@@ -21,6 +21,10 @@  sdl.mo-objs := sdl.o sdl_zoom.o
 endif
 ifeq ($(CONFIG_SDLABI),2.0)
 sdl.mo-objs := sdl2.o sdl2-input.o sdl2-2d.o
+ifeq ($(CONFIG_OPENGL),y)
+sdl.mo-objs += sdl2-gl.o
+libs_softmmu += $(OPENGL_LIBS)
+endif
 endif
 sdl.mo-cflags := $(SDL_CFLAGS)
 
diff --git a/ui/sdl.c b/ui/sdl.c
index 3e9d810..1fe002d 100644
--- a/ui/sdl.c
+++ b/ui/sdl.c
@@ -873,6 +873,17 @@  static const DisplayChangeListenerOps dcl_ops = {
     .dpy_cursor_define = sdl_mouse_define,
 };
 
+void sdl_display_early_init(int opengl)
+{
+    if (opengl == 1 /* on */) {
+        fprintf(stderr,
+                "SDL1 display code has no opengl support.\n"
+                "Please recompile qemu with SDL2, using\n"
+                "./configure --enable-sdl --with-sdlabi=2.0\n");
+        exit(1);
+    }
+}
+
 void sdl_display_init(DisplayState *ds, int full_screen, int no_frame)
 {
     int flags;
diff --git a/ui/sdl2-2d.c b/ui/sdl2-2d.c
index 9264817..85f1be4 100644
--- a/ui/sdl2-2d.c
+++ b/ui/sdl2-2d.c
@@ -42,6 +42,8 @@  void sdl2_2d_update(DisplayChangeListener *dcl,
     DisplaySurface *surf = qemu_console_surface(dcl->con);
     SDL_Rect rect;
 
+    assert(!scon->opengl);
+
     if (!surf) {
         return;
     }
@@ -67,6 +69,8 @@  void sdl2_2d_switch(DisplayChangeListener *dcl,
     DisplaySurface *old_surface = scon->surface;
     int format = 0;
 
+    assert(!scon->opengl);
+
     scon->surface = new_surface;
 
     if (scon->texture) {
@@ -107,12 +111,15 @@  void sdl2_2d_refresh(DisplayChangeListener *dcl)
 {
     struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);
 
+    assert(!scon->opengl);
     graphic_hw_update(dcl->con);
     sdl2_poll_events(scon);
 }
 
 void sdl2_2d_redraw(struct sdl2_console *scon)
 {
+    assert(!scon->opengl);
+
     if (!scon->surface) {
         return;
     }
diff --git a/ui/sdl2-gl.c b/ui/sdl2-gl.c
new file mode 100644
index 0000000..b8620ca
--- /dev/null
+++ b/ui/sdl2-gl.c
@@ -0,0 +1,114 @@ 
+/*
+ * QEMU SDL display driver
+ *
+ * Copyright (c) 2003 Fabrice Bellard
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+/* Ported SDL 1.2 code to 2.0 by Dave Airlie. */
+
+/* Avoid compiler warning because macro is redefined in SDL_syswm.h. */
+#undef WIN32_LEAN_AND_MEAN
+
+#include <SDL.h>
+#include <SDL_syswm.h>
+#include <SDL_opengl.h>
+
+#include "qemu-common.h"
+#include "ui/console.h"
+#include "ui/input.h"
+#include "ui/sdl2.h"
+#include "sysemu/sysemu.h"
+
+static void sdl2_gl_render_surface(struct sdl2_console *scon)
+{
+    int ww, wh;
+
+    SDL_GL_MakeCurrent(scon->real_window, scon->winctx);
+
+    SDL_GetWindowSize(scon->real_window, &ww, &wh);
+    surface_gl_setup_viewport(scon->surface, ww, wh);
+
+    surface_gl_render_texture(scon->surface);
+    SDL_GL_SwapWindow(scon->real_window);
+}
+
+void sdl2_gl_update(DisplayChangeListener *dcl,
+                    int x, int y, int w, int h)
+{
+    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);
+
+    assert(scon->opengl);
+
+    SDL_GL_MakeCurrent(scon->real_window, scon->winctx);
+    surface_gl_update_texture(scon->surface, x, y, w, h);
+    scon->updates++;
+}
+
+void sdl2_gl_switch(DisplayChangeListener *dcl,
+                    DisplaySurface *new_surface)
+{
+    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);
+    DisplaySurface *old_surface = scon->surface;
+
+    assert(scon->opengl);
+
+    SDL_GL_MakeCurrent(scon->real_window, scon->winctx);
+    surface_gl_destroy_texture(scon->surface);
+
+    scon->surface = new_surface;
+
+    if (!new_surface) {
+        sdl2_window_destroy(scon);
+        return;
+    }
+
+    if (!scon->real_window) {
+        sdl2_window_create(scon);
+    } else if (old_surface &&
+               ((surface_width(old_surface)  != surface_width(new_surface)) ||
+                (surface_height(old_surface) != surface_height(new_surface)))) {
+        sdl2_window_resize(scon);
+    }
+
+    surface_gl_create_texture(scon->surface);
+}
+
+void sdl2_gl_refresh(DisplayChangeListener *dcl)
+{
+    struct sdl2_console *scon = container_of(dcl, struct sdl2_console, dcl);
+
+    assert(scon->opengl);
+
+    graphic_hw_update(dcl->con);
+    if (scon->updates && scon->surface) {
+        scon->updates = 0;
+        sdl2_gl_render_surface(scon);
+    }
+    sdl2_poll_events(scon);
+}
+
+void sdl2_gl_redraw(struct sdl2_console *scon)
+{
+    assert(scon->opengl);
+
+    if (scon->surface) {
+        sdl2_gl_render_surface(scon);
+    }
+}
diff --git a/ui/sdl2.c b/ui/sdl2.c
index 1ae2781..7dd8a87 100644
--- a/ui/sdl2.c
+++ b/ui/sdl2.c
@@ -92,6 +92,9 @@  void sdl2_window_create(struct sdl2_console *scon)
                                          surface_height(scon->surface),
                                          flags);
     scon->real_renderer = SDL_CreateRenderer(scon->real_window, -1, 0);
+    if (scon->opengl) {
+        scon->winctx = SDL_GL_GetCurrentContext();
+    }
     sdl_update_caption(scon);
 }
 
@@ -118,6 +121,17 @@  void sdl2_window_resize(struct sdl2_console *scon)
                       surface_height(scon->surface));
 }
 
+static void sdl2_redraw(struct sdl2_console *scon)
+{
+    if (scon->opengl) {
+#ifdef CONFIG_OPENGL
+        sdl2_gl_redraw(scon);
+#endif
+    } else {
+        sdl2_2d_redraw(scon);
+    }
+}
+
 static void sdl_update_caption(struct sdl2_console *scon)
 {
     char win_title[1024];
@@ -316,7 +330,7 @@  static void toggle_full_screen(struct sdl2_console *scon)
         }
         SDL_SetWindowFullscreen(scon->real_window, 0);
     }
-    sdl2_2d_redraw(scon);
+    sdl2_redraw(scon);
 }
 
 static void handle_keydown(SDL_Event *ev)
@@ -364,8 +378,10 @@  static void handle_keydown(SDL_Event *ev)
         case SDL_SCANCODE_U:
             sdl2_window_destroy(scon);
             sdl2_window_create(scon);
-            /* re-create texture */
-            sdl2_2d_switch(&scon->dcl, scon->surface);
+            if (!scon->opengl) {
+                /* re-create scon->texture */
+                sdl2_2d_switch(&scon->dcl, scon->surface);
+            }
             gui_keysym = 1;
             break;
 #if 0
@@ -384,7 +400,7 @@  static void handle_keydown(SDL_Event *ev)
                 fprintf(stderr, "%s: scale to %dx%d\n",
                         __func__, width, height);
                 sdl_scale(scon, width, height);
-                sdl2_2d_redraw(scon);
+                sdl2_redraw(scon);
                 gui_keysym = 1;
             }
 #endif
@@ -520,10 +536,10 @@  static void handle_windowevent(SDL_Event *ev)
             info.height = ev->window.data2;
             dpy_set_ui_info(scon->dcl.con, &info);
         }
-        sdl2_2d_redraw(scon);
+        sdl2_redraw(scon);
         break;
     case SDL_WINDOWEVENT_EXPOSED:
-        sdl2_2d_redraw(scon);
+        sdl2_redraw(scon);
         break;
     case SDL_WINDOWEVENT_FOCUS_GAINED:
     case SDL_WINDOWEVENT_ENTER:
@@ -676,6 +692,37 @@  static const DisplayChangeListenerOps dcl_2d_ops = {
     .dpy_cursor_define = sdl_mouse_define,
 };
 
+#ifdef CONFIG_OPENGL
+static const DisplayChangeListenerOps dcl_gl_ops = {
+    .dpy_name          = "sdl2-gl",
+    .dpy_gfx_update    = sdl2_gl_update,
+    .dpy_gfx_switch    = sdl2_gl_switch,
+    .dpy_refresh       = sdl2_gl_refresh,
+    .dpy_mouse_set     = sdl_mouse_warp,
+    .dpy_cursor_define = sdl_mouse_define,
+};
+#endif
+
+void sdl_display_early_init(int opengl)
+{
+    switch (opengl) {
+    case -1: /* default */
+    case 0:  /* off */
+        break;
+    case 1: /* on */
+#ifdef CONFIG_OPENGL
+        display_opengl = 1;
+#else
+        fprintf(stderr, "SDL2 has been compiled without opengl support\n");
+        exit(1);
+#endif
+        break;
+    default:
+        g_assert_not_reached();
+        break;
+    }
+}
+
 void sdl_display_init(DisplayState *ds, int full_screen, int no_frame)
 {
     int flags;
@@ -721,10 +768,16 @@  void sdl_display_init(DisplayState *ds, int full_screen, int no_frame)
         if (!qemu_console_is_graphic(con)) {
             sdl2_console[i].hidden = true;
         }
+        sdl2_console[i].idx = i;
+#ifdef CONFIG_OPENGL
+        sdl2_console[i].opengl = display_opengl;
+        sdl2_console[i].dcl.ops = display_opengl ? &dcl_gl_ops : &dcl_2d_ops;
+#else
+        sdl2_console[i].opengl = 0;
         sdl2_console[i].dcl.ops = &dcl_2d_ops;
+#endif
         sdl2_console[i].dcl.con = con;
         register_displaychangelistener(&sdl2_console[i].dcl);
-        sdl2_console[i].idx = i;
     }
 
     /* Load a 32x32x4 image. White pixels are transparent. */
diff --git a/vl.c b/vl.c
index 06e8f44..008e4bf 100644
--- a/vl.c
+++ b/vl.c
@@ -1939,6 +1939,7 @@  static DisplayType select_display(const char *p)
 {
     const char *opts;
     DisplayType display = DT_DEFAULT;
+    int opengl = -1;
 
     if (strstart(p, "sdl", &opts)) {
 #ifdef CONFIG_SDL
@@ -1982,6 +1983,15 @@  static DisplayType select_display(const char *p)
                 } else {
                     goto invalid_sdl_args;
                 }
+            } else if (strstart(opts, ",gl=", &nextopt)) {
+                opts = nextopt;
+                if (strstart(opts, "on", &nextopt)) {
+                    opengl = 1;
+                } else if (strstart(opts, "off", &nextopt)) {
+                    opengl = 0;
+                } else {
+                    goto invalid_sdl_args;
+                }
             } else {
             invalid_sdl_args:
                 fprintf(stderr, "Invalid SDL option string: %s\n", p);
@@ -1989,6 +1999,7 @@  static DisplayType select_display(const char *p)
             }
             opts = nextopt;
         }
+        sdl_display_early_init(opengl);
 #else
         fprintf(stderr, "SDL support is disabled\n");
         exit(1);