[gegl/samplers] lohalo: further testing (with VIPS) identifies the best minmod macro

[Nicolas Robidoux <nrobidoux src gnome org>]

commit 141dbea1a7e64b73d79f186ac3cd40469e7ae2f8
Author: Nicolas Robidoux <nicolas robidoux gmail com>
Date:   Wed Jun 22 15:53:26 2011 -0400

    lohalo: further testing (with VIPS) identifies the best minmod macro

 gegl/buffer/gegl-sampler-lohalo.c |   22 ++++++++++++----------
 1 files changed, 12 insertions(+), 10 deletions(-)
---
diff --git a/gegl/buffer/gegl-sampler-lohalo.c b/gegl/buffer/gegl-sampler-lohalo.c
index 0e9156a..253afea 100644
--- a/gegl/buffer/gegl-sampler-lohalo.c
+++ b/gegl/buffer/gegl-sampler-lohalo.c
@@ -110,7 +110,7 @@
  * For uncompressed natural images in high bit depth (images for which
  * the slopes a and b are unlikely to be equal to zero or be equal to
  * each other), or chips with good branch prediction, the following
- * version of the minmod function may work well.
+ * version of the minmod function may work well:
  *
  * ( (a_times_b)>=0. ? ( (a_times_b)<(a_times_a) ? (b) : (a) ) : 0. )
  *
@@ -130,16 +130,9 @@
  * ( (a_times_b)>=0. ? ( (a_times_a)<=(a_times_b) ? (a) : (b) ) : 0. )
  *
  * This last version appears to be slightly better than the former in
- * speed tests performed on a recent multicore Intel chip. 
+ * speed tests performed on a recent multicore Intel chip, especially
+ * when enlarging a sharp image by a large factor, hence the choice.
  */
-#define LOHALO_MINMOD(a,b,a_times_a,a_times_b) \
-  (                                            \
-    ( (a_times_b)>=(gfloat) 0. )               \
-    ?                                          \
-    ( (a_times_a)<=(a_times_b) ? (a) : (b) )   \
-    :                                          \
-    (gfloat) 0.                                \
-  )
 
 /* #define LOHALO_MINMOD(a,b,a_times_a,a_times_b) \ */
 /*   (                                            \ */
@@ -150,6 +143,15 @@
 /*     (gfloat) 0.                                \ */
 /*   )                                              */
 
+#define LOHALO_MINMOD(a,b,a_times_a,a_times_b) \
+  (                                            \
+    ( (a_times_b)>=(gfloat) 0. )               \
+    ?                                          \
+    ( (a_times_a)<=(a_times_b) ? (a) : (b) )   \
+    :                                          \
+    (gfloat) 0.                                \
+  )
+
 
 /*
  * Macros set up so the likely winner in in the first argument