[gimp/pippin/linear-is-the-new-black] app: use gimp_blend_composites utility function in lch modes

[Øyvind Kolås <ok src gnome org>]

commit 1f0e35037315c3c498520a8c62f44d770d551e31
Author: Øyvind Kolås <pippin gimp org>
Date:   Wed Jan 18 22:55:37 2017 +0100

    app: use gimp_blend_composites utility function in lch modes

 .../layer-modes/gimpoperationlchchroma.c           |    2 +-
 app/operations/layer-modes/gimpoperationlchcolor.c |    2 +-
 app/operations/layer-modes/gimpoperationlchhue.c   |    2 +-
 .../layer-modes/gimpoperationlchlightness.c        |    2 +-
 .../layer-modes/gimpoperationpointlayermode.h      |   41 +-------------------
 5 files changed, 6 insertions(+), 43 deletions(-)
---
diff --git a/app/operations/layer-modes/gimpoperationlchchroma.c 
b/app/operations/layer-modes/gimpoperationlchchroma.c
index f446de5..3e5d5c8 100644
--- a/app/operations/layer-modes/gimpoperationlchchroma.c
+++ b/app/operations/layer-modes/gimpoperationlchchroma.c
@@ -145,7 +145,7 @@ gimp_operation_lch_chroma_process_pixels (gfloat                *in,
      to_fish = babl_fish ("CIE Lab alpha float", "R'G'B'A float");
 
   chroma_pre_process (from_fish, to_fish, in, layer, out, samples);
-  gimp_operation_layer_composite (in, layer, mask, out, opacity, samples);
+  compfun_src_atop (in, layer, mask, opacity, out, samples);
 
   return TRUE;
 }
diff --git a/app/operations/layer-modes/gimpoperationlchcolor.c 
b/app/operations/layer-modes/gimpoperationlchcolor.c
index 43ecb8e..013f182 100644
--- a/app/operations/layer-modes/gimpoperationlchcolor.c
+++ b/app/operations/layer-modes/gimpoperationlchcolor.c
@@ -136,7 +136,7 @@ gimp_operation_lch_color_process_pixels (gfloat                *in,
      to_fish = babl_fish ("CIE Lab alpha float", "R'G'B'A float");
 
   color_pre_process (from_fish_la, from_fish_laba, to_fish, in, layer, out, samples);
-  gimp_operation_layer_composite (in, layer, mask, out, opacity, samples);
+  compfun_src_atop (in, layer, mask, opacity, out, samples);
 
   return TRUE;
 }
diff --git a/app/operations/layer-modes/gimpoperationlchhue.c 
b/app/operations/layer-modes/gimpoperationlchhue.c
index 226dd6e..543f689 100644
--- a/app/operations/layer-modes/gimpoperationlchhue.c
+++ b/app/operations/layer-modes/gimpoperationlchhue.c
@@ -144,7 +144,7 @@ gimp_operation_lch_hue_process_pixels (gfloat                *in,
      to_fish = babl_fish ("CIE Lab alpha float", "R'G'B'A float");
 
   hue_pre_process (from_fish, to_fish, in, layer, out, samples);
-  gimp_operation_layer_composite (in, layer, mask, out, opacity, samples);
+  compfun_src_atop (in, layer, mask, opacity, out, samples);
 
   return TRUE;
 }
diff --git a/app/operations/layer-modes/gimpoperationlchlightness.c 
b/app/operations/layer-modes/gimpoperationlchlightness.c
index 6cd1e7f..3ba5a18 100644
--- a/app/operations/layer-modes/gimpoperationlchlightness.c
+++ b/app/operations/layer-modes/gimpoperationlchlightness.c
@@ -131,7 +131,7 @@ gimp_operation_lch_lightness_process_pixels (gfloat                *in,
 
 
   lightness_pre_process (from_fish_la, from_fish_laba, to_fish, in, layer, out, samples);
-  gimp_operation_layer_composite (in, layer, mask, out, opacity, samples);
+  compfun_src_atop (in, layer, mask, opacity, out, samples);
 
   return TRUE;
 }
diff --git a/app/operations/layer-modes/gimpoperationpointlayermode.h 
b/app/operations/layer-modes/gimpoperationpointlayermode.h
index b9f2463..5274f9a 100644
--- a/app/operations/layer-modes/gimpoperationpointlayermode.h
+++ b/app/operations/layer-modes/gimpoperationpointlayermode.h
@@ -67,42 +67,6 @@ extern const Babl *_gimp_fish_laba_to_rgba;
 extern const Babl *_gimp_fish_laba_to_perceptual;
 
 static inline void
-gimp_operation_layer_composite (const gfloat *in,
-                                const gfloat *layer,
-                                const gfloat *mask,
-                                gfloat       *out,
-                                gfloat        opacity,
-                                glong         samples)
-{
-  while (samples--)
-    {
-      gfloat comp_alpha = layer[ALPHA] * opacity;
-      if (mask)
-        comp_alpha *= *mask++;
-      if (comp_alpha != 0.0f)
-        {
-          out[RED]   = out[RED]   * comp_alpha + in[RED]   * (1.0f - comp_alpha);
-          out[GREEN] = out[GREEN] * comp_alpha + in[GREEN] * (1.0f - comp_alpha);
-          out[BLUE]  = out[BLUE]  * comp_alpha + in[BLUE]  * (1.0f - comp_alpha);
-        }
-      else
-        {
-          gint b;
-          for (b = RED; b < ALPHA; b++)
-            {
-              out[b] = in[b];
-            }
-        }
-
-      out[ALPHA] = in[ALPHA];
-
-      in    += 4;
-      layer += 4;
-      out   += 4;
-    }
-}
-
-static inline void
 compfun_src_atop (gfloat *in,
                   gfloat *layer,
                   gfloat *mask,
@@ -165,10 +129,9 @@ compfun_src_over (gfloat *in,
         else
         {
           gint   b;
-          //gfloat ratio = comp_alpha / new_alpha;
+          gfloat ratio = comp_alpha / new_alpha;
           for (b = RED; b < ALPHA; b++)
-            //out[b] = ratio * (in[ALPHA] * (layer[b] - layer[b]) + layer[b] - in[b]) + in[b];
-            out[b] = layer[b] * comp_alpha + in[b] * (1.0f - comp_alpha);
+            out[b] = layer[b] * ratio + in[b] * (1.0f - ratio);
         }
  
       out[ALPHA] = new_alpha;