gl_common: split into platform specific files

Do this instead of stuffing all x11/cocoa/win32/wayland specific code
into gl_common.c. The cocoa specific parts could probably go directly
into cocoa_common.m, possibly same with wayland.

Also redo how the list of backends is managed. Get rid of the GLTYPE_
constants. Instead of having a big switch() on GLTYPE_, each backend
entry has a function pointer to setup the MPGLContext callback (e.g.
mpgl_set_backend_x11()).

Makefile

@@ -97,9 +97,12 @@ SOURCES-$(GL)                   += video/out/gl_common.c video/out/gl_osd.c \
 
 SOURCES-$(ENCODING)             += video/out/vo_lavc.c audio/out/ao_lavc.c \
                                    core/encode_lavc.c
-SOURCES-$(GL_WIN32)             += video/out/w32_common.c
-SOURCES-$(GL_X11)               += video/out/x11_common.c
-SOURCES-$(GL_WAYLAND)           += video/out/wayland_common.c
+
+SOURCES-$(GL_WIN32)             += video/out/w32_common.c video/out/gl_w32.c
+SOURCES-$(GL_X11)               += video/out/x11_common.c video/out/gl_x11.c
+SOURCES-$(GL_COCOA)             += video/out/gl_cocoa.c
+SOURCES-$(GL_WAYLAND)           += video/out/wayland_common.c \
+                                   video/out/gl_wayland.c
 
 SOURCES-$(JACK)                 += audio/out/ao_jack.c
 SOURCES-$(JOYSTICK)             += core/input/joystick.c

video/out/gl_cocoa.c

@@ -0,0 +1,67 @@
+/*
+ * MPlayer is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * MPlayer is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with MPlayer; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * You can alternatively redistribute this file and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ */
+
+#include "cocoa_common.h"
+#include "gl_common.h"
+
+static bool config_window_cocoa(struct MPGLContext *ctx, uint32_t d_width,
+                                uint32_t d_height, uint32_t flags)
+{
+    int rv = vo_cocoa_config_window(ctx->vo, d_width, d_height, flags,
+                                    ctx->requested_gl_version >= MPGL_VER(3, 0));
+    if (rv != 0)
+        return false;
+
+    mpgl_load_functions(ctx->gl, (void *)vo_cocoa_glgetaddr, NULL);
+
+    ctx->depth_r = vo_cocoa_cgl_color_size(ctx->vo);
+    ctx->depth_g = vo_cocoa_cgl_color_size(ctx->vo);
+    ctx->depth_b = vo_cocoa_cgl_color_size(ctx->vo);
+
+    if (!ctx->gl->SwapInterval)
+        ctx->gl->SwapInterval = vo_cocoa_swap_interval;
+
+    return true;
+}
+
+static void releaseGlContext_cocoa(MPGLContext *ctx)
+{
+}
+
+static void swapGlBuffers_cocoa(MPGLContext *ctx)
+{
+    vo_cocoa_swap_buffers(ctx->vo);
+}
+
+void mpgl_set_backend_cocoa(MPGLContext *ctx)
+{
+    ctx->config_window = config_window_cocoa;
+    ctx->releaseGlContext = releaseGlContext_cocoa;
+    ctx->swapGlBuffers = swapGlBuffers_cocoa;
+    ctx->check_events = vo_cocoa_check_events;
+    ctx->update_xinerama_info = vo_cocoa_update_xinerama_info;
+    ctx->fullscreen = vo_cocoa_fullscreen;
+    ctx->ontop = vo_cocoa_ontop;
+    ctx->vo_init = vo_cocoa_init;
+    ctx->pause = vo_cocoa_pause;
+    ctx->resume = vo_cocoa_resume;
+    ctx->vo_uninit = vo_cocoa_uninit;
+}