[gegl/threaded-base-classes] only disable 1x1 hot-tile code paths when multi threaded

[Øyvind Kolås <ok src gnome org>]

commit 3cd0891e0d08c89f3c8048a6bd437882369210ec
Author: Øyvind Kolås <pippin gimp org>
Date:   Fri Jun 27 10:03:09 2014 +0200

    only disable 1x1 hot-tile code paths when multi threaded

 gegl/buffer/gegl-buffer-access.c   |    5 +++--
 gegl/buffer/gegl-sampler-nearest.c |   24 ++++++++++++++++--------
 gegl/gegl-config.h                 |    2 ++
 gegl/gegl-init.c                   |    7 +++++++
 4 files changed, 28 insertions(+), 10 deletions(-)
---
diff --git a/gegl/buffer/gegl-buffer-access.c b/gegl/buffer/gegl-buffer-access.c
index a54cbe3..3f723ba 100644
--- a/gegl/buffer/gegl-buffer-access.c
+++ b/gegl/buffer/gegl-buffer-access.c
@@ -1330,10 +1330,11 @@ gegl_buffer_set (GeglBuffer          *buffer,
   if (format == NULL)
     format = buffer->soft_format;
 
-  /*if (rect && (rect->width == 1 && rect->height == 1))
+  if (rect && (rect->width == 1 && rect->height == 1) &&
+    gegl_config()->threads == 1)
       _gegl_buffer_set_pixel (buffer, rect->x, rect->y, format, src,
                               GEGL_BUFFER_SET_FLAG_LOCK|GEGL_BUFFER_SET_FLAG_NOTIFY);
-  else*/
+  else
     _gegl_buffer_set_with_flags (buffer, rect, level, format, src, rowstride,
                                  GEGL_BUFFER_SET_FLAG_LOCK|
                                  GEGL_BUFFER_SET_FLAG_NOTIFY);
diff --git a/gegl/buffer/gegl-sampler-nearest.c b/gegl/buffer/gegl-sampler-nearest.c
index 21d3d87..4461a83 100644
--- a/gegl/buffer/gegl-sampler-nearest.c
+++ b/gegl/buffer/gegl-sampler-nearest.c
@@ -26,7 +26,7 @@
 #include "gegl-buffer-private.h"
 #include "gegl-tile-storage.h"
 #include "gegl-tile-backend.h"
-
+#include "gegl-config.h"
 #include "gegl-sampler-nearest.h"
 
 enum
@@ -180,7 +180,7 @@ gegl_sampler_nearest_get_same_format  (      GeglSampler*    restrict  sampler,
 }
 
 static void
-gegl_sampler_nearest_get (      GeglSampler*    restrict  sampler,
+gegl_sampler_nearest_get_threaded (      GeglSampler*    restrict  sampler,
                           const gdouble                   absolute_x,
                           const gdouble                   absolute_y,
                                 GeglMatrix2              *scale,
@@ -191,10 +191,17 @@ gegl_sampler_nearest_get (      GeglSampler*    restrict  sampler,
                         (gint) floorf ((double) absolute_y),1,1};
   gegl_buffer_get (sampler->buffer, &rect, 1.0, sampler->format, output, GEGL_AUTO_ROWSTRIDE, repeat_mode);
   return;
+}
 
-  /*
-
-#if 0
+static void
+gegl_sampler_nearest_get (      GeglSampler*    restrict  sampler,
+                          const gdouble                   absolute_x,
+                          const gdouble                   absolute_y,
+                                GeglMatrix2              *scale,
+                                void*           restrict  output,
+                                GeglAbyssPolicy           repeat_mode)
+{
+#if 1
   gegl_sampler_get_pixel (sampler,
            floorf(absolute_x), floorf(absolute_y),
            output, repeat_mode);
@@ -206,8 +213,6 @@ gegl_sampler_nearest_get (      GeglSampler*    restrict  sampler,
                           repeat_mode);
   babl_process (sampler->fish, in_bptr, output, 1);
 #endif
-
-  */
 }
 
 
@@ -218,14 +223,17 @@ gegl_sampler_nearest_prepare (GeglSampler* restrict sampler)
     return;
   GEGL_SAMPLER_NEAREST (sampler)->buffer_bpp = babl_format_get_bytes_per_pixel (sampler->buffer->format);
 
+  if (gegl_config()->threads > 1)
+    sampler->get = gegl_sampler_nearest_get_threaded;
+
 #if 0 // maybe re-enable; when certain result is correct
   if (sampler->format == sampler->buffer->soft_format)
     {
       sampler->get = gegl_sampler_nearest_get_same_format;
     }
   else
+#endif
     {
       sampler->fish = babl_fish (sampler->buffer->soft_format, sampler->format);
     }
-#endif
 }
diff --git a/gegl/gegl-config.h b/gegl/gegl-config.h
index 607c883..f5330d0 100644
--- a/gegl/gegl-config.h
+++ b/gegl/gegl-config.h
@@ -52,6 +52,8 @@ struct _GeglConfigClass
   GObjectClass parent_class;
 };
 
+gint gegl_config_threads (void);
+
 G_END_DECLS
 
 #endif
diff --git a/gegl/gegl-init.c b/gegl/gegl-init.c
index 91baf04..ff8ac8e 100644
--- a/gegl/gegl-init.c
+++ b/gegl/gegl-init.c
@@ -399,6 +399,13 @@ GeglConfig *gegl_config (void)
   return config;
 }
 
+gint gegl_config_threads (void)
+{
+  if (!config)
+    config = gegl_config ();
+  return config->threads;
+}
+
 static void swap_clean (void)
 {
   const gchar  *swap_dir = gegl_swap_dir ();