image prepares - put in some disabled code to show how to possibly use

this is how you would possibly use prepare stages for objects like
image objects by pre-rendering them to a buffer. this is not complete
and it's actually disabled right now, but it's to show how it might be
done. some more exploring is needed, but this is to share how it
might/should work.

src/lib/evas/canvas/evas_image_private.h

@@ -107,6 +107,7 @@ struct _Evas_Image_Data
    const Evas_Object_Image_Pixels *pixels;
 
    void             *engine_data;
+   void             *engine_data_prep;
    Efl_Vpath_File   *file_obj;
 
    int               pixels_checked_out;

src/lib/evas/canvas/evas_object_image.c

@@ -51,7 +51,7 @@ static int evas_object_image_get_opaque_rect(Evas_Object *eo_obj,
 					     void *type_private_data,
 					     Evas_Coord *x, Evas_Coord *y, Evas_Coord *w, Evas_Coord *h);
 static int evas_object_image_can_map(Evas_Object *eo_obj);
-static void evas_object_image_render_prepare(Evas_Object *obj, Evas_Object_Protected_Data *pd);
+static void evas_object_image_render_prepare(Evas_Object *obj, Evas_Object_Protected_Data *pd, Eina_Bool do_async);
 
 static void evas_object_image_filled_resize_listener(void *data, Evas *eo_e, Evas_Object *eo_obj, void *einfo);
 
@@ -114,7 +114,7 @@ Eina_Cow *evas_object_image_pixels_cow = NULL;
 Eina_Cow *evas_object_image_state_cow = NULL;
 
 static void
-evas_object_image_render_prepare(Evas_Object *eo_obj, Evas_Object_Protected_Data *obj)
+evas_object_image_render_prepare(Evas_Object *eo_obj, Evas_Object_Protected_Data *obj, Eina_Bool do_async EINA_UNUSED)
 {
    Evas_Image_Data *o = efl_data_scope_get(eo_obj, MY_CLASS);
 
@@ -122,8 +122,45 @@ evas_object_image_render_prepare(Evas_Object *eo_obj, Evas_Object_Protected_Data
    if ((o->cur->u.file) || (o->written) || (o->cur->frame != 0))
      {
         if (o->engine_data) ENFN->image_prepare(ENDT, o->engine_data);
-        return;
      }
+#if 0
+   if (
+       ((o->cur->border.l != 0) || (o->cur->border.r != 0) ||
+        (o->cur->border.t != 0) || (o->cur->border.b != 0)) &&
+       ((obj->cur->geometry.w < 256) && (obj->cur->geometry.h < 256))
+      )
+     {
+        void *ctx, *prep = NULL;
+        int x, y, w, h;
+
+        if (!o->engine_data_prep)
+          {
+             prep = ENFN->image_surface_noscale_new
+               (ENDT, obj->cur->geometry.w, obj->cur->geometry.h,
+                o->cur->has_alpha);
+             ENFN->image_surface_noscale_region_get(ENDT, prep,
+                                                    &x, &y, &w, &h);
+             ctx = ENFN->context_new(ENDT);
+             ENFN->context_clip_set(ENDT, ctx, x, y, w, h);
+             ENFN->context_render_op_set(ENDT, ctx, EVAS_RENDER_COPY);
+             if (o->cur->has_alpha)
+               {
+                  ENFN->context_color_set(ENDT, ctx, 128, 64, 0, 128);
+                  ENFN->rectangle_draw(ENDT, ctx, prep, x, y, w, h, do_async);
+               }
+             printf("REND image, region %i %i %ix%i = %i %i\n",
+                    x, y, w, h,
+                    x - obj->cur->geometry.x, y - obj->cur->geometry.y);
+             evas_object_image_render(eo_obj, obj, obj->private_data, ENDT,
+                                      ctx, prep,
+                                      x - obj->cur->geometry.x,
+                                      y - obj->cur->geometry.y,
+                                      do_async);
+             ENFN->context_free(ENDT, ctx);
+             o->engine_data_prep = prep;
+          }
+     }
+#endif
    // XXX: if image is a proxy, PREPEND to prerender list in evas canvas
 }
 
@@ -1438,6 +1475,10 @@ evas_object_image_free(Evas_Object *eo_obj, Evas_Object_Protected_Data *obj)
 	     }
            ENFN->image_free(ENDT, o->engine_data);
 	 }
+       if (o->engine_data_prep)
+         {
+           ENFN->image_free(ENDT, o->engine_data_prep);
+         }
        if (o->video_surface)
 	 {
 	   o->video_surface = EINA_FALSE;
@@ -1445,6 +1486,7 @@ evas_object_image_free(Evas_Object *eo_obj, Evas_Object_Protected_Data *obj)
 	 }
      }
    o->engine_data = NULL;
+   o->engine_data_prep = NULL;
    if (o->file_obj)
      {
         efl_del(o->file_obj);
@@ -1745,6 +1787,16 @@ evas_object_image_render(Evas_Object *eo_obj, Evas_Object_Protected_Data *obj, v
         return;
      }
 
+   if (o->engine_data_prep)
+     {
+        ENFN->image_draw(output, context, surface, o->engine_data_prep,
+                         0, 0, obj->cur->geometry.w, obj->cur->geometry.h,
+                         obj->cur->geometry.x + x, obj->cur->geometry.y + y,
+                         obj->cur->geometry.w, obj->cur->geometry.h,
+                         0, do_async);
+        return;
+     }
+
    /* We are displaying the overlay */
    if (o->video_visible)
      {
@@ -2147,6 +2199,7 @@ evas_object_image_render_pre(Evas_Object *eo_obj,
 {
    Evas_Image_Data *o = type_private_data;
    int is_v = 0, was_v = 0;
+   Eina_Bool changed_prep = EINA_TRUE;
 
    /* dont pre-render the obj twice! */
    if (obj->pre_render_done) return;
@@ -2305,8 +2358,16 @@ evas_object_image_render_pre(Evas_Object *eo_obj,
         (obj->cur->geometry.h != obj->prev->geometry.h))
       )
      {
-        evas_object_render_pre_prev_cur_add(&e->clip_changes, eo_obj, obj);
-        goto done;
+        if ((obj->cur->geometry.w == obj->prev->geometry.w) &&
+            (obj->cur->geometry.h == obj->prev->geometry.h))
+          {
+             evas_object_render_pre_prev_cur_add(&e->clip_changes, eo_obj, obj);
+          }
+        else
+          {
+             evas_object_render_pre_prev_cur_add(&e->clip_changes, eo_obj, obj);
+             goto done;
+          }
      }
    if (o->changed)
      {
@@ -2543,6 +2604,7 @@ evas_object_image_render_pre(Evas_Object *eo_obj,
                                                 x + e->framespace.x,
                                                 y + e->framespace.y,
                                                 w, h);
+        changed_prep = EINA_FALSE;
      }
    done:
    evas_object_render_pre_effect_updates(&e->clip_changes, eo_obj, is_v, was_v);
@@ -2559,6 +2621,15 @@ evas_object_image_render_pre(Evas_Object *eo_obj,
           }
         EINA_COW_PIXEL_WRITE_END(o, pixi_write);
      }
+   if (changed_prep)
+     {
+        if (o->engine_data_prep)
+          {
+             ENFN->image_free(ENDT, o->engine_data_prep);
+             o->engine_data_prep = NULL;
+          }
+     }
+   o->changed = EINA_FALSE;
 }
 
 static void

src/lib/evas/canvas/evas_render.c

@@ -2754,7 +2754,7 @@ evas_render_updates_internal(Evas *eo_e,
         if (prepare)
           {
              if (obj->func->render_prepare)
-               obj->func->render_prepare(eo_obj, obj);
+               obj->func->render_prepare(eo_obj, obj, do_async);
           }
      }
    eina_evlog("-render_phase5", eo_e, 0.0, NULL);

src/lib/evas/include/evas_private.h

@@ -1292,7 +1292,7 @@ struct _Evas_Object_Func
 // new - add to prepare list during render if object needs some pre-render
 // preparation - may include rendering content to buffer or loading data
 // from disk or uploading to texture etc.
-   void (*render_prepare) (Evas_Object *obj, Evas_Object_Protected_Data *pd);
+   void (*render_prepare) (Evas_Object *obj, Evas_Object_Protected_Data *pd, Eina_Bool do_async);
 
 // new render2 functions