sdl2: add support for display rendering using opengl.

Add new sdl2-gl.c file, with display
rendering functions using opengl.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>

5 files changed, 190 insertions, 7 deletions

diff --git a/ui/Makefile.objs b/ui/Makefile.objs
index 67fe278..029a42a 100644
--- a/ui/Makefile.objs
+++ b/ui/Makefile.objs
@@ -21,6 +21,9 @@ 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
+endif
 endif
 sdl.mo-cflags := $(SDL_CFLAGS)
 
diff --git a/ui/sdl.c b/ui/sdl.c
index 8bdbf52..3be2910 100644
--- a/ui/sdl.c
+++ b/ui/sdl.c
@@ -908,6 +908,16 @@ 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");
+    }
+}
+
 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 46ef5f7..bb56747 100644
--- a/ui/sdl2-2d.c
+++ b/ui/sdl2-2d.c
@@ -36,6 +36,8 @@ void sdl2_2d_update(DisplayChangeListener *dcl,
     DisplaySurface *surf = qemu_console_surface(dcl->con);
     SDL_Rect rect;
 
+    assert(!scon->opengl);
+
     if (!surf) {
         return;
     }
@@ -61,6 +63,8 @@ void sdl2_2d_switch(DisplayChangeListener *dcl,
     DisplaySurface *old_surface = scon->surface;
     int format = 0;
 
+    assert(!scon->opengl);
+
     scon->surface = new_surface;
 
     if (scon->texture) {
@@ -101,12 +105,15 @@ 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..b604c06
--- /dev/null
+++ b/ui/sdl2-gl.c
@@ -0,0 +1,112 @@
+/*
+ * QEMU SDL display driver -- opengl support
+ *
+ * Copyright (c) 2014 Red Hat
+ *
+ * Authors:
+ *     Gerd Hoffmann <kraxel@redhat.com>
+ *
+ * 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.
+ */
+
+#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->gls, scon->surface, ww, wh);
+
+    surface_gl_render_texture(scon->gls, 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->gls, 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->gls, scon->surface);
+
+    scon->surface = new_surface;
+
+    if (!new_surface) {
+        console_gl_fini_context(scon->gls);
+        scon->gls = NULL;
+        sdl2_window_destroy(scon);
+        return;
+    }
+
+    if (!scon->real_window) {
+        sdl2_window_create(scon);
+        scon->gls = console_gl_init_context();
+    } 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->gls, 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 610ddb0..2d60179 100644
--- a/ui/sdl2.c
+++ b/ui/sdl2.c
@@ -86,6 +86,9 @@ 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);
 }
 
@@ -112,6 +115,17 @@ 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];
@@ -310,7 +324,7 @@ 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)
@@ -358,8 +372,10 @@ 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
@@ -378,7 +394,7 @@ 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
@@ -514,10 +530,10 @@ 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:
@@ -671,6 +687,35 @@ 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_gfx_check_format    = console_gl_check_format,
+    .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;
+#endif
+        break;
+    default:
+        g_assert_not_reached();
+        break;
+    }
+}
+
 void sdl_display_init(DisplayState *ds, int full_screen, int no_frame)
 {
     int flags;
@@ -716,10 +761,16 @@ 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. */