From 96feb074d085977345fe11363a1844136303ab68 Mon Sep 17 00:00:00 2001
From: Toad King <toadking@toadking.com>
Date: Wed, 2 Jul 2014 21:56:22 -0400
Subject: [PATCH] (EMSCRIPTEN) add shared context support

---
 Makefile.emscripten             |  3 ++-
 gfx/context/emscriptenegl_ctx.c | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/Makefile.emscripten b/Makefile.emscripten
index a6d976ce5f..82a4cab37a 100644
--- a/Makefile.emscripten
+++ b/Makefile.emscripten
@@ -57,7 +57,8 @@ HAVE_SDL = 0
 HAVE_ZLIB = 1
 HAVE_FBO = 1
 WANT_MINIZ = 1
-MEMORY = 67108864
+#MEMORY = 67108864
+MEMORY = 134217728
 LTO = 0
 # XXX: setting this to 1/2 currently crashes Firefox nightly
 PRECISE_F32 = 0
diff --git a/gfx/context/emscriptenegl_ctx.c b/gfx/context/emscriptenegl_ctx.c
index 236c7986e8..4b8d98e562 100644
--- a/gfx/context/emscriptenegl_ctx.c
+++ b/gfx/context/emscriptenegl_ctx.c
@@ -32,12 +32,14 @@
 #include <EGL/egl.h>
 #include <EGL/eglext.h>
 
+static EGLContext g_egl_hw_ctx;
 static EGLContext g_egl_ctx;
 static EGLSurface g_egl_surf;
 static EGLDisplay g_egl_dpy;
 static EGLConfig g_config;
 
 static bool g_inited;
+static bool g_use_hw_ctx;
 
 static unsigned g_fb_width;
 static unsigned g_fb_height;
@@ -153,6 +155,16 @@ static bool gfx_ctx_init(void *data)
    if (!g_egl_ctx)
       goto error;
 
+   if (g_use_hw_ctx)
+   {
+      g_egl_hw_ctx = eglCreateContext(g_egl_dpy, g_config, g_egl_ctx,
+            context_attributes);
+      RARCH_LOG("[VC/EGL]: Created shared context: %p.\n", (void*)g_egl_hw_ctx);
+
+      if (g_egl_hw_ctx == EGL_NO_CONTEXT)
+         goto error;
+   }
+
    // create an EGL window surface
    g_egl_surf = eglCreateWindowSurface(g_egl_dpy, g_config, 0, NULL);
    if (!g_egl_surf)
@@ -271,6 +283,14 @@ static bool gfx_ctx_write_egl_image(void *data, const void *frame, unsigned widt
    return false;
 }
 
+static void gfx_ctx_bind_hw_render(void *data, bool enable)
+{
+   (void)data;
+   g_use_hw_ctx = enable;
+   if (g_egl_dpy && g_egl_surf)
+      eglMakeCurrent(g_egl_dpy, g_egl_surf, g_egl_surf, enable ? g_egl_hw_ctx : g_egl_ctx);
+}
+
 const gfx_ctx_driver_t gfx_ctx_emscripten = {
    gfx_ctx_init,
    gfx_ctx_destroy,
@@ -290,4 +310,5 @@ const gfx_ctx_driver_t gfx_ctx_emscripten = {
    gfx_ctx_write_egl_image,
    NULL,
    "emscripten",
+   gfx_ctx_bind_hw_render,
 };