[gegl] buffer: do sampler interpolation in buffers space

[Øyvind "pippin" Kolås <ok src gnome org>]

commit 4882c453bc4ed6351a714b2f199e54ca7d305641
Author: Øyvind Kolås <pippin gimp org>
Date:   Fri Jul 6 16:59:22 2018 +0200

    buffer: do sampler interpolation in buffers space

 gegl/buffer/gegl-sampler-cubic.c   | 1 -
 gegl/buffer/gegl-sampler-linear.c  | 1 -
 gegl/buffer/gegl-sampler-lohalo.c  | 2 --
 gegl/buffer/gegl-sampler-nearest.c | 1 -
 gegl/buffer/gegl-sampler-nohalo.c  | 2 --
 gegl/buffer/gegl-sampler.c         | 4 +++-
 6 files changed, 3 insertions(+), 8 deletions(-)
---
diff --git a/gegl/buffer/gegl-sampler-cubic.c b/gegl/buffer/gegl-sampler-cubic.c
index 78ab93d90..7764c66cd 100644
--- a/gegl/buffer/gegl-sampler-cubic.c
+++ b/gegl/buffer/gegl-sampler-cubic.c
@@ -117,7 +117,6 @@ gegl_sampler_cubic_init (GeglSamplerCubic *self)
   GEGL_SAMPLER (self)->level[0].context_rect.y = -2;
   GEGL_SAMPLER (self)->level[0].context_rect.width = 5;
   GEGL_SAMPLER (self)->level[0].context_rect.height = 5;
-  GEGL_SAMPLER (self)->interpolate_format = gegl_babl_rgbA_linear_float ();
 
   self->b=1.0;
   self->c=0.0;
diff --git a/gegl/buffer/gegl-sampler-linear.c b/gegl/buffer/gegl-sampler-linear.c
index b4310fd2c..a70159234 100644
--- a/gegl/buffer/gegl-sampler-linear.c
+++ b/gegl/buffer/gegl-sampler-linear.c
@@ -70,7 +70,6 @@ gegl_sampler_linear_init (GeglSamplerLinear *self)
   GEGL_SAMPLER (self)->level[0].context_rect.y      = -1 -   LINEAR_EXTRA_ELBOW_ROOM;
   GEGL_SAMPLER (self)->level[0].context_rect.width  =  3 + 2*LINEAR_EXTRA_ELBOW_ROOM;
   GEGL_SAMPLER (self)->level[0].context_rect.height =  3 + 2*LINEAR_EXTRA_ELBOW_ROOM;
-  GEGL_SAMPLER (self)->interpolate_format = gegl_babl_rgbA_linear_float ();
 }
 
 void
diff --git a/gegl/buffer/gegl-sampler-lohalo.c b/gegl/buffer/gegl-sampler-lohalo.c
index c6c39a893..53d811916 100644
--- a/gegl/buffer/gegl-sampler-lohalo.c
+++ b/gegl/buffer/gegl-sampler-lohalo.c
@@ -186,8 +186,6 @@ gegl_sampler_lohalo_init (GeglSamplerLohalo *self)
   level->context_rect.y   = -LOHALO_OFFSET_0;
   level->context_rect.width  = LOHALO_SIZE_0;
   level->context_rect.height = LOHALO_SIZE_0;
-
-  GEGL_SAMPLER (self)->interpolate_format = gegl_babl_rgbA_linear_float ();
 }
 
 /*
diff --git a/gegl/buffer/gegl-sampler-nearest.c b/gegl/buffer/gegl-sampler-nearest.c
index 5565bfb4a..3c8ed1cc9 100644
--- a/gegl/buffer/gegl-sampler-nearest.c
+++ b/gegl/buffer/gegl-sampler-nearest.c
@@ -75,7 +75,6 @@ gegl_sampler_nearest_init (GeglSamplerNearest *self)
   GEGL_SAMPLER (self)->level[0].context_rect.y = 0;
   GEGL_SAMPLER (self)->level[0].context_rect.width = 1;
   GEGL_SAMPLER (self)->level[0].context_rect.height = 1;
-  GEGL_SAMPLER (self)->interpolate_format = gegl_babl_rgbA_linear_float ();
 }
 
 static void
diff --git a/gegl/buffer/gegl-sampler-nohalo.c b/gegl/buffer/gegl-sampler-nohalo.c
index 858dc3284..e989be912 100644
--- a/gegl/buffer/gegl-sampler-nohalo.c
+++ b/gegl/buffer/gegl-sampler-nohalo.c
@@ -294,8 +294,6 @@ gegl_sampler_nohalo_init (GeglSamplerNohalo *self)
   level->context_rect.y   = -NOHALO_OFFSET_0;
   level->context_rect.width  = NOHALO_SIZE_0;
   level->context_rect.height = NOHALO_SIZE_0;
-
-  GEGL_SAMPLER (self)->interpolate_format = gegl_babl_rgbA_linear_float ();
 }
 
 static void inline
diff --git a/gegl/buffer/gegl-sampler.c b/gegl/buffer/gegl-sampler.c
index b63dbeca7..17f9deb1c 100644
--- a/gegl/buffer/gegl-sampler.c
+++ b/gegl/buffer/gegl-sampler.c
@@ -193,7 +193,9 @@ gegl_sampler_prepare (GeglSampler *self)
 
   if (klass->prepare)
     klass->prepare (self);
-  
+
+  self->interpolate_format = babl_format_with_space ("RaGaBaA float",
+                                         gegl_buffer_get_format(self->buffer));
   if (!self->fish)
     self->fish = babl_fish (self->interpolate_format, self->format);