Evas GL: (GL thread) Added the EvasGL pixel callback threading

EvasGL pixel callback function will be moved to thread when application set a special flag.

Two major modifications are included in this patch:
  - Added an option bit to enable thread rendering for pixel callback function (spec is changed)
  - Redirected the get_pixel callback to threadable function

How to enable the option in application code:
  Evas_GL_Config config = evas_gl_config_new();
  config->options_bits |= EVAS_GL_OPTIONS_THREAD;

Change-Id: I33281c9b23b1e1f1023c112f8bb4ded8b2b714b0

6 files changed, 88 insertions, 4 deletions

diff --git a/src/lib/evas/Evas_GL.h b/src/lib/evas/Evas_GL.h
index 8669c92172..26e7dd0147 100644
--- a/src/lib/evas/Evas_GL.h
+++ b/src/lib/evas/Evas_GL.h
@@ -512,9 +512,12 @@ typedef enum _Evas_GL_Options_Bits
 {
    EVAS_GL_OPTIONS_NONE    = 0,     /**< No extra options */
    EVAS_GL_OPTIONS_DIRECT  = (1<<0),/**< Optional hint to allow rendering directly to the Evas window if possible */
-   EVAS_GL_OPTIONS_CLIENT_SIDE_ROTATION = (1<<1) /**< Force direct rendering even if the canvas is rotated.
+   EVAS_GL_OPTIONS_CLIENT_SIDE_ROTATION = (1<<1),/**< Force direct rendering even if the canvas is rotated.
                                                   *   In that case, it is the application's role to rotate the contents of
-                                                  *   the Evas_GL view. @see evas_gl_rotation_get. @since 1.12 */
+                                                  *   the Evas_GL view. @see evas_gl_rotation_get */
+   EVAS_GL_OPTIONS_THREAD  = (1<<2) /**< If enabled, Evas GL pixel callback will be called by another thread instead of main thread.
+                                     * This option can enhance performance because Evas GL is worked with aynchronized call,
+                                     * but user must guarantee synchronization with pixel callback and main loop when using this flag. */
 } Evas_GL_Options_Bits;
 
 /**
diff --git a/src/lib/evas/canvas/evas_object_image.c b/src/lib/evas/canvas/evas_object_image.c
index 08fdb1f163..bbed6c699d 100644
--- a/src/lib/evas/canvas/evas_object_image.c
+++ b/src/lib/evas/canvas/evas_object_image.c
@@ -1652,7 +1652,10 @@ evas_process_dirty_pixels(Evas_Object *eo_obj, Evas_Object_Protected_Data *obj,
                {
                   if (ENFN->gl_get_pixels_pre)
                     ENFN->gl_get_pixels_pre(output);
-                  o->pixels->func.get_pixels(o->pixels->func.get_pixels_data, eo_obj);
+                  if (ENFN->gl_get_pixels)
+                    ENFN->gl_get_pixels(output, o->pixels->func.get_pixels, o->pixels->func.get_pixels_data, eo_obj, o->engine_data);
+                  else
+                    o->pixels->func.get_pixels(o->pixels->func.get_pixels_data, eo_obj);
                   if (ENFN->gl_get_pixels_post)
                     ENFN->gl_get_pixels_post(output);
                }
@@ -1696,7 +1699,10 @@ evas_process_dirty_pixels(Evas_Object *eo_obj, Evas_Object_Protected_Data *obj,
                   // Auto-fallback to FBO rendering (for perf & power consumption)
                   if (ENFN->gl_get_pixels_pre)
                     ENFN->gl_get_pixels_pre(output);
-                  o->pixels->func.get_pixels(o->pixels->func.get_pixels_data, obj->object);
+                  if (ENFN->gl_get_pixels)
+                    ENFN->gl_get_pixels(output, o->pixels->func.get_pixels, o->pixels->func.get_pixels_data, eo_obj, o->engine_data);
+                  else
+                    o->pixels->func.get_pixels(o->pixels->func.get_pixels_data, eo_obj);
                   if (ENFN->gl_get_pixels_post)
                     ENFN->gl_get_pixels_post(output);
                   o->direct_render = EINA_FALSE;
diff --git a/src/lib/evas/include/evas_private.h b/src/lib/evas/include/evas_private.h
index b75ef49613..210f54b2bb 100644
--- a/src/lib/evas/include/evas_private.h
+++ b/src/lib/evas/include/evas_private.h
@@ -1560,6 +1560,8 @@ struct _Evas_Func
    void  (*ector_end)                    (void *data, void *context, Ector_Surface *ector, void *surface, void *engine_data, Eina_Bool do_async);
    void* (*ector_new)                    (void *data, void *context, Ector_Surface *ector, void *surface);
    void  (*ector_free)                   (void *engine_data);
+
+   void (*gl_get_pixels)                 (void *data, Evas_Object_Image_Pixels_Get_Cb cb, void *get_pixels_data, Evas_Object *o, void *image);
 };
 
 struct _Evas_Image_Save_Func
diff --git a/src/modules/evas/engines/gl_common/evas_gl_core.c b/src/modules/evas/engines/gl_common/evas_gl_core.c
index 593130b3dd..77faf26dba 100644
--- a/src/modules/evas/engines/gl_common/evas_gl_core.c
+++ b/src/modules/evas/engines/gl_common/evas_gl_core.c
@@ -1482,6 +1482,8 @@ try_again:
                     }
                }
 
+             sfc->thread_rendering = !!(cfg->options_bits & EVAS_GL_OPTIONS_THREAD);
+
              cfg_index = i;
              break;
           }
diff --git a/src/modules/evas/engines/gl_common/evas_gl_core_private.h b/src/modules/evas/engines/gl_common/evas_gl_core_private.h
index 3b7540f67d..7ae1c1748c 100644
--- a/src/modules/evas/engines/gl_common/evas_gl_core_private.h
+++ b/src/modules/evas/engines/gl_common/evas_gl_core_private.h
@@ -126,6 +126,8 @@ struct _EVGL_Surface
    unsigned buffers_skip_allocate : 1;
    unsigned buffers_allocated : 1;
 
+   unsigned thread_rendering : 1;
+
    void   *cfg;
    int     cfg_index;
 
diff --git a/src/modules/evas/engines/gl_generic/evas_engine.c b/src/modules/evas/engines/gl_generic/evas_engine.c
index 92daa03af5..da0638d431 100644
--- a/src/modules/evas/engines/gl_generic/evas_engine.c
+++ b/src/modules/evas/engines/gl_generic/evas_engine.c
@@ -1781,6 +1781,74 @@ eng_gl_get_pixels_pre(void *data)
    evgl_get_pixels_pre();
 }
 
+typedef struct
+{
+   Evas_Object_Image_Pixels_Get_Cb cb;
+   void *get_pixels_data;
+   Evas_Object *o;
+} Evas_GL_Thread_Command_get_pixels;
+
+static void
+_evgl_thread_get_pixels(void *data)
+{
+   Evas_GL_Thread_Command_get_pixels *thread_param =
+      (Evas_GL_Thread_Command_get_pixels *)data;
+
+  evas_evgl_thread_begin();
+  thread_param->cb(thread_param->get_pixels_data, thread_param->o);
+  evas_evgl_thread_end();
+
+  eina_mempool_free(_mp_command, thread_param);
+}
+
+static void
+get_pixels_evgl_thread_cmd(Evas_Object_Image_Pixels_Get_Cb cb, void *get_pixels_data, Evas_Object *o)
+{
+   if (!evas_gl_thread_enabled()) /* XXX */
+     {
+        cb(get_pixels_data, o);
+        return;
+     }
+
+   Evas_GL_Thread_Command_get_pixels *thread_param;
+   thread_param = eina_mempool_malloc(_mp_command,
+                                      sizeof(Evas_GL_Thread_Command_get_pixels));
+   thread_param->cb = cb;
+   thread_param->get_pixels_data = get_pixels_data;
+   thread_param->o = o;
+   evas_gl_thread_cmd_enqueue(EVAS_GL_THREAD_TYPE_EVGL,
+                              _evgl_thread_get_pixels,
+                              thread_param,
+                              EVAS_GL_THREAD_MODE_FLUSH);
+}
+
+static void
+eng_gl_get_pixels(void *data EINA_UNUSED, Evas_Object_Image_Pixels_Get_Cb cb, void *get_pixels_data, Evas_Object *o, void *image)
+{
+   Evas_GL_Image *im = image;
+   Evas_Native_Surface *n;
+   EVGL_Surface *sfc;
+
+   if (im)
+     {
+        n = im->native.data;
+        if (n)
+          {
+             sfc = n->data.evasgl.surface;
+             if (sfc)
+               {
+                  if (sfc->thread_rendering)
+                    {
+                       get_pixels_evgl_thread_cmd(cb, get_pixels_data, o);
+                       return;
+                    }
+               }
+          }
+     }
+
+   cb(get_pixels_data, o);
+}
+
 static void
 eng_gl_get_pixels_post(void *data EINA_UNUSED)
 {
@@ -3260,6 +3328,7 @@ module_open(Evas_Module *em)
    ORD(gl_surface_direct_renderable_get);
    ORD(gl_get_pixels_set);
    ORD(gl_get_pixels_pre);
+   ORD(gl_get_pixels);
    ORD(gl_get_pixels_post);
    ORD(gl_surface_lock);
    ORD(gl_surface_read_pixels);