[gegl] stereographic-projection: merge radius/zoom parameters

[Øyvind Kolås <ok src gnome org>]

commit 671090ae3343d93b736ec7e4065a199d765de62e
Author: Øyvind Kolås <pippin gimp org>
Date:   Fri May 2 22:44:40 2014 +0200

    stereographic-projection: merge radius/zoom parameters

 operations/common/gnomonic-projection.c      |    6 ++----
 operations/common/stereographic-projection.c |   19 +++++++------------
 2 files changed, 9 insertions(+), 16 deletions(-)
---
diff --git a/operations/common/gnomonic-projection.c b/operations/common/gnomonic-projection.c
index 02a5bdc..26d5d0f 100644
--- a/operations/common/gnomonic-projection.c
+++ b/operations/common/gnomonic-projection.c
@@ -42,7 +42,6 @@ gegl_chant_enum (sampler_type, _("Sampler"), GeglSamplerType, gegl_sampler_type,
 #include <glib/gi18n-lib.h>
 #include "gegl-chant.h"
 
-
 static void
 prepare (GeglOperation *operation)
 {
@@ -77,13 +76,13 @@ calc_long_lat (float x, float  y,
   float sin_c, cos_c;
 
   p = sqrtf (x*x+y*y);
-  c = atanf (p);
+  c = atan2f (p, 1);
 
   sin_c = sinf(c);
   cos_c = cosf(c);
 
   latitude = asinf (cos_c * sin_tilt + ( y * sin_c * cos_tilt) / p);
-  longtitude = pan + atan2f ( x * sin_c, p * cos_tilt * cos_c - y * sin_tilt * sin_c);
+  longtitude = pan + atan2f (x * sin_c, p * cos_tilt * cos_c - y * sin_tilt * sin_c);
 
   if (longtitude < 0)
     longtitude += M_PI * 2;
@@ -184,7 +183,6 @@ process (GeglOperation       *operation,
 
               gegl_sampler_get (sampler, cx * in_rect.width, cy * in_rect.height,
                                 scale, out, GEGL_ABYSS_NONE);
-
               in  += 4;
               out += 4;
 
diff --git a/operations/common/stereographic-projection.c b/operations/common/stereographic-projection.c
index 82361b4..711e186 100644
--- a/operations/common/stereographic-projection.c
+++ b/operations/common/stereographic-projection.c
@@ -29,8 +29,6 @@ gegl_chant_double (spin, _("spin"), -360.0, 360.0, 0.0,
        _("spin of camera / rendering"))
 gegl_chant_double (zoom, _("zoom"), 0.01, 1000.0, 50.0, 
        _("scale factor"))
-gegl_chant_double (radius, _("local radius"), 0.01, 100.0, 5.0, 
-       _("factor determining dimension of planet"))
 
 gegl_chant_enum (sampler_type, _("Sampler"), GeglSamplerType, gegl_sampler_type,
                  GEGL_SAMPLER_CUBIC, _("Image resampling method to use"))
@@ -44,7 +42,6 @@ gegl_chant_enum (sampler_type, _("Sampler"), GeglSamplerType, gegl_sampler_type,
 #include <glib/gi18n-lib.h>
 #include "gegl-chant.h"
 
-
 static void
 prepare (GeglOperation *operation)
 {
@@ -70,20 +67,19 @@ get_required_for_output (GeglOperation       *operation,
 
 static void inline
 calc_long_lat (float x, float  y,
-               float tilt, float pan, float spin, float radius,
+               float tilt, float pan, float spin,
                float sin_tilt, float cos_tilt,
                float *in_long, float *in_lat)
 {
   float p, c;
   float longtitude, latitude;
   float sin_c, cos_c;
-  float R = radius;
 
   p = sqrtf (x*x+y*y);
-  c = 2 * atanf (p / 2 * R);
+  c = 2 * atan2f (p / 2, 1);
 
-  sin_c = sinf(c);
-  cos_c = cosf(c);
+  sin_c = sinf (c);
+  cos_c = cosf (c);
 
   latitude = asinf (cos_c * sin_tilt + ( y * sin_c * cos_tilt) / p);
   longtitude = pan + atan2f ( x * sin_c, p * cos_tilt * cos_c - y * sin_tilt * sin_c);
@@ -105,7 +101,7 @@ process (GeglOperation       *operation,
   GeglChantO *o = GEGL_CHANT_PROPERTIES (operation);
   float pan = o->pan / 360 * M_PI * 2;
   float spin = o->spin / 360 * M_PI * 2;
-  float zoom = o->zoom / 100.0;
+  float zoom = o->zoom / 100.0 / 10;
   float tilt = o->tilt / 360 * M_PI * 2;
   float width;
   float height;
@@ -119,7 +115,6 @@ process (GeglOperation       *operation,
   GeglRectangle in_rect = *gegl_operation_source_get_bounding_box (operation, "input");
   GeglMatrix2  scale_matrix;
   GeglMatrix2 *scale = NULL;
-  float radius = o->radius;
 
   format_io = babl_format ("RaGaBaA float");
   sampler = gegl_buffer_sampler_new (input, format_io, o->sampler_type);
@@ -168,7 +163,7 @@ process (GeglOperation       *operation,
                   calc_long_lat (\
                       xx * cos_spin - yy * sin_spin,\
                       yy * cos_spin + xx * sin_spin,\
-                      tilt, pan, spin, radius,\
+                      tilt, pan, spin, \
                       sin_tilt, cos_tilt,\
                       &rx, &ry);\
   ud = rx;vd = ry;}
@@ -181,7 +176,7 @@ process (GeglOperation       *operation,
                   calc_long_lat (
                       u * cos_spin - v * sin_spin,
                       v * cos_spin + u * sin_spin,
-                      tilt, pan, spin, radius,
+                      tilt, pan, spin,
                       sin_tilt, cos_tilt,
                       &cx, &cy);
               }