From daec5ccc57d6ab5a71f946e07ec8fba0bba4c9df Mon Sep 17 00:00:00 2001
From: Brandon Wright <bearoso@gmail.com>
Date: Sun, 21 Oct 2018 17:05:37 -0500
Subject: [PATCH] Better Wayland OpenGL. Still breaks with scale factors.

---
 gtk/Makefile.am                       |  5 +++
 gtk/configure.ac                      |  3 ++
 gtk/src/gtk_display_driver_opengl.cpp | 56 +++++++++++++++++++++++++++
 gtk/src/gtk_display_driver_opengl.h   |  8 ++++
 4 files changed, 72 insertions(+)

diff --git a/gtk/Makefile.am b/gtk/Makefile.am
index 053c0b6d..8e090ec6 100644
--- a/gtk/Makefile.am
+++ b/gtk/Makefile.am
@@ -125,6 +125,11 @@ snes9x_gtk_SOURCES += \
     ../c4emu.cpp
 endif
 
+if WAYLAND
+snes9x_gtk_SOURCES += \
+    src/gtk_wayland_helpers.cpp
+endif
+
 # APU
 snes9x_gtk_SOURCES += \
     ../apu/apu.cpp
diff --git a/gtk/configure.ac b/gtk/configure.ac
index 0ac8e514..ef13cde6 100644
--- a/gtk/configure.ac
+++ b/gtk/configure.ac
@@ -223,9 +223,11 @@ if test yes = "$with_opengl" ; then
     LIBS="$LIBS $EPOXY_LIBS"
 fi
 
+WAYLAND=0
 PKG_CHECK_MODULES([WAYLAND_EGL],[wayland-egl],[
     CFLAGS="$CFLAGS $WAYLAND_EGL_CFLAGS"
     LIBS="$LIBS $WAYLAND_EGL_LIBS"
+    WAYLAND=yes
 ],[
     echo "Not using Wayland-EGL."
 ])
@@ -499,6 +501,7 @@ AM_CONDITIONAL(PULSEAUDIO, [test yes = "$PULSEAUDIO"])
 AM_CONDITIONAL(HQ2X, [test yes = "$HQ2X"])
 AM_CONDITIONAL(XBRZ, [test yes = "$XBRZ"])
 AM_CONDITIONAL(SYSTEM_ZIP, [test yes = "$SYSTEM_ZIP"])
+AM_CONDITIONAL(WAYLAND, [test yes = "$WAYLAND"])
 
 AC_SUBST(NASM)
 AC_SUBST(NASM_FLAGS)
diff --git a/gtk/src/gtk_display_driver_opengl.cpp b/gtk/src/gtk_display_driver_opengl.cpp
index a9e1b2e7..3cfe56bb 100644
--- a/gtk/src/gtk_display_driver_opengl.cpp
+++ b/gtk/src/gtk_display_driver_opengl.cpp
@@ -16,6 +16,14 @@
 
 #include "shaders/shader_helpers.h"
 
+#ifdef GDK_WINDOWING_WAYLAND
+#define ON_WAYLAND(BLOCK) if (GDK_IS_WAYLAND_DISPLAY (gdk_display_get_default())) \
+                          { \
+                              BLOCK \
+                          }
+#else
+#define ON_WAYLAND(BLOCK) do {} while (0);
+#endif
 
 static void S9xViewportCallback (int src_width, int src_height,
                                  int viewport_x, int viewport_y,
@@ -662,6 +670,12 @@ S9xOpenGLDisplayDriver::refresh (int width, int height)
 void
 S9xOpenGLDisplayDriver::resize_window (int width, int height)
 {
+    ON_WAYLAND
+    (
+        wl.resize (width, height);
+        wl.swap_interval (config->sync_to_vblank);
+        return;
+    )
 
     gdk_window_destroy (gdk_window);
     create_window (width, height);
@@ -706,6 +720,20 @@ S9xOpenGLDisplayDriver::create_window (int width, int height)
 int
 S9xOpenGLDisplayDriver::init_gl (void)
 {
+    ON_WAYLAND
+    (
+        gdk_window = gtk_widget_get_window (drawing_area);
+        if (!wl.attach (gdk_window))
+            return 0;
+
+        if (!wl.create_egl_context (256, 224))
+            return 0;
+
+        wl.make_current ();
+
+        return 1;
+    )
+
     int glx_attribs[] = { GLX_RGBA, GLX_DOUBLEBUFFER, None };
 
     display = GDK_DISPLAY_XDISPLAY (gdk_display_get_default ());
@@ -788,6 +816,11 @@ S9xOpenGLDisplayDriver::swap_control (int enable)
 {
     enable = enable ? 1 : 0;
 
+    ON_WAYLAND
+    (
+        wl.swap_interval (enable);
+    )
+
 #ifdef GDK_WINDOWING_X11
     const char *extensions = (const char *) glGetString (GL_EXTENSIONS);
 
@@ -827,6 +860,19 @@ S9xOpenGLDisplayDriver::get_current_buffer (void)
 void
 S9xOpenGLDisplayDriver::gl_swap (void)
 {
+    ON_WAYLAND
+    (
+        wl.swap_buffers ();
+
+        if (config->sync_every_frame)
+        {
+            usleep (0);
+            glFinish ();
+        }
+
+        return;
+    )
+
 #ifdef GDK_WINDOWING_X11
     glXSwapBuffers (display, xwindow);
 #endif
@@ -880,6 +926,11 @@ S9xOpenGLDisplayDriver::deinit (void)
 
     glDeleteTextures (1, &texmap);
 
+    ON_WAYLAND
+    (
+        return;
+    )
+
     glXDestroyContext (display, glx_context);
     gdk_window_destroy (gdk_window);
     XFree (vi);
@@ -899,6 +950,11 @@ S9xOpenGLDisplayDriver::query_availability (void)
 {
     GdkDisplay *gdk_display = gdk_display_get_default ();
 
+    ON_WAYLAND
+    (
+        return 1;
+    )
+
 #ifdef GDK_WINDOWING_X11
     if (GDK_IS_X11_DISPLAY (gdk_display))
     {
diff --git a/gtk/src/gtk_display_driver_opengl.h b/gtk/src/gtk_display_driver_opengl.h
index c2c6624d..ee72c1f0 100644
--- a/gtk/src/gtk_display_driver_opengl.h
+++ b/gtk/src/gtk_display_driver_opengl.h
@@ -9,6 +9,10 @@
 #include <epoxy/glx.h>
 #endif
 
+#ifdef GDK_WINDOWING_WAYLAND
+#include "gtk_wayland_helpers.h"
+#endif
+
 #include "shaders/glsl.h"
 
 #define PBO_FMT_16 0
@@ -85,6 +89,10 @@ class S9xOpenGLDisplayDriver : public S9xDisplayDriver
         XVisualInfo              *vi;
         GLXContext               glx_context;
 #endif
+
+#ifdef GDK_WINDOWING_WAYLAND
+        wlgl_helper              wl;
+#endif
 };
 
 #endif /* __GTK_DISPLAY_DRIVER_OPENGL_H */