[gimp/gimp-2-10] Issue #2345 - Add xyY to color sample readouts

[Michael Natterer <mitch src gnome org>]

commit 59682a1cb1235cc7f9b9c4650dad680c3c764cb1
Author: Elle Stone <ellestone ninedegreesbelow com>
Date:   Mon Oct 22 17:34:11 2018 -0400

    Issue #2345 - Add xyY to color sample readouts
    
    Add xyY color space to the color spaces for sampling colors.
    
    Also add code to xcf-load.c that makes sure the sample point loading
    code handles unknown future GimpColorPickMode values (fall back to
    PIXEL pick mode).
    
    (cherry picked from commit 298cc57042b97cde2a6a7ef4dc5b89eeb40fd2e5)

 app/core/core-enums.c        |  2 ++
 app/core/core-enums.h        |  9 ++++++-
 app/widgets/gimpcolorframe.c | 64 +++++++++++++++++++++++++++++++++++++-------
 app/xcf/xcf-load.c           |  3 +++
 4 files changed, 68 insertions(+), 10 deletions(-)
---
diff --git a/app/core/core-enums.c b/app/core/core-enums.c
index 2bc635773f..aa0db6bb59 100644
--- a/app/core/core-enums.c
+++ b/app/core/core-enums.c
@@ -141,6 +141,7 @@ gimp_color_pick_mode_get_type (void)
     { GIMP_COLOR_PICK_MODE_LCH, "GIMP_COLOR_PICK_MODE_LCH", "lch" },
     { GIMP_COLOR_PICK_MODE_LAB, "GIMP_COLOR_PICK_MODE_LAB", "lab" },
     { GIMP_COLOR_PICK_MODE_CMYK, "GIMP_COLOR_PICK_MODE_CMYK", "cmyk" },
+    { GIMP_COLOR_PICK_MODE_XYY, "GIMP_COLOR_PICK_MODE_XYY", "xyy" },
     { 0, NULL, NULL }
   };
 
@@ -153,6 +154,7 @@ gimp_color_pick_mode_get_type (void)
     { GIMP_COLOR_PICK_MODE_LCH, NC_("color-pick-mode", "CIE LCh"), NULL },
     { GIMP_COLOR_PICK_MODE_LAB, NC_("color-pick-mode", "CIE LAB"), NULL },
     { GIMP_COLOR_PICK_MODE_CMYK, NC_("color-pick-mode", "CMYK"), NULL },
+    { GIMP_COLOR_PICK_MODE_XYY, NC_("color-pick-mode", "CIE xyY"), NULL },
     { 0, NULL, NULL }
   };
 
diff --git a/app/core/core-enums.h b/app/core/core-enums.h
index 4916ae117f..1c063a5bea 100644
--- a/app/core/core-enums.h
+++ b/app/core/core-enums.h
@@ -86,6 +86,10 @@ typedef enum  /*< pdb-skip >*/
 } GimpChannelBorderStyle;
 
 
+/*  Note: when appending values here, don't forget to update
+ *  GimpColorFrame and other places use this enum to create combo
+ *  boxes.
+ */
 #define GIMP_TYPE_COLOR_PICK_MODE (gimp_color_pick_mode_get_type ())
 
 GType gimp_color_pick_mode_get_type (void) G_GNUC_CONST;
@@ -98,7 +102,10 @@ typedef enum  /*< pdb-skip >*/
   GIMP_COLOR_PICK_MODE_HSV,         /*< desc="HSV"          >*/
   GIMP_COLOR_PICK_MODE_LCH,         /*< desc="CIE LCh"      >*/
   GIMP_COLOR_PICK_MODE_LAB,         /*< desc="CIE LAB"      >*/
-  GIMP_COLOR_PICK_MODE_CMYK         /*< desc="CMYK"         >*/
+  GIMP_COLOR_PICK_MODE_CMYK,        /*< desc="CMYK"         >*/
+  GIMP_COLOR_PICK_MODE_XYY,         /*< desc="CIE xyY"      >*/
+
+  GIMP_COLOR_PICK_MODE_LAST = GIMP_COLOR_PICK_MODE_XYY /*< skip >*/
 } GimpColorPickMode;
 
 
diff --git a/app/widgets/gimpcolorframe.c b/app/widgets/gimpcolorframe.c
index 01454c1252..9e4e4a05a2 100644
--- a/app/widgets/gimpcolorframe.c
+++ b/app/widgets/gimpcolorframe.c
@@ -135,17 +135,31 @@ gimp_color_frame_class_init (GimpColorFrameClass *klass)
 static void
 gimp_color_frame_init (GimpColorFrame *frame)
 {
-  GtkWidget *vbox;
-  GtkWidget *vbox2;
-  GtkWidget *label;
-  gint       i;
+  GtkListStore *store;
+  GtkWidget    *vbox;
+  GtkWidget    *vbox2;
+  GtkWidget    *label;
+  gint          i;
 
   frame->sample_valid  = FALSE;
   frame->sample_format = babl_format ("R'G'B' u8");
 
   gimp_rgba_set (&frame->color, 0.0, 0.0, 0.0, GIMP_OPACITY_OPAQUE);
 
-  frame->combo = gimp_enum_combo_box_new (GIMP_TYPE_COLOR_PICK_MODE);
+  /* create the store manually so the values have a nice order */
+  store = gimp_enum_store_new_with_values (GIMP_TYPE_COLOR_PICK_MODE,
+                                           GIMP_COLOR_PICK_MODE_LAST + 1,
+                                           GIMP_COLOR_PICK_MODE_PIXEL,
+                                           GIMP_COLOR_PICK_MODE_RGB_PERCENT,
+                                           GIMP_COLOR_PICK_MODE_RGB_U8,
+                                           GIMP_COLOR_PICK_MODE_HSV,
+                                           GIMP_COLOR_PICK_MODE_LCH,
+                                           GIMP_COLOR_PICK_MODE_LAB,
+                                           GIMP_COLOR_PICK_MODE_XYY,
+                                           GIMP_COLOR_PICK_MODE_CMYK);
+  frame->combo = gimp_enum_combo_box_new_with_model (GIMP_ENUM_STORE (store));
+  g_object_unref (store);
+
   gtk_frame_set_label_widget (GTK_FRAME (frame), frame->combo);
   gtk_widget_show (frame->combo);
 
@@ -916,10 +930,42 @@ gimp_color_frame_update (GimpColorFrame *frame)
 
           values = g_new0 (gchar *, 5);
 
-          values[0] = g_strdup_printf ("%.01f  ",        lab[0]);
-          values[1] = g_strdup_printf ("%.01f  ",        lab[1]);
-          values[2] = g_strdup_printf ("%.01f  ",        lab[2]);
-          values[3] = g_strdup_printf ("%.01f %%",       lab[3] * 100.0);
+          values[0] = g_strdup_printf ("%.01f  ",  lab[0]);
+          values[1] = g_strdup_printf ("%.01f  ",  lab[1]);
+          values[2] = g_strdup_printf ("%.01f  ",  lab[2]);
+          values[3] = g_strdup_printf ("%.01f %%", lab[3] * 100.0);
+        }
+      break;
+
+    case GIMP_COLOR_PICK_MODE_XYY:
+      /* TRANSLATORS: x from xyY color space */
+      names[0] = C_("xyY color space", "x:");
+      /* TRANSLATORS: y from xyY color space */
+      names[1] = C_("xyY color space", "y:");
+      /* TRANSLATORS: Y from xyY color space */
+      names[2] = C_("xyY color space", "Y:");
+
+      if (has_alpha)
+        /* TRANSLATORS: A for Alpha (color transparency) */
+        names[3] = C_("Alpha channel", "A:");
+
+      if (frame->sample_valid)
+        {
+          static const Babl *fish = NULL;
+          gfloat             xyY[4];
+
+          if (G_UNLIKELY (! fish))
+            fish = babl_fish (babl_format ("R'G'B'A double"),
+                              babl_format ("CIE xyY alpha float"));
+
+          babl_process (fish, &frame->color, xyY, 1);
+
+          values = g_new0 (gchar *, 5);
+
+          values[0] = g_strdup_printf ("%1.6f  ",  xyY[0]);
+          values[1] = g_strdup_printf ("%1.6f  ",  xyY[1]);
+          values[2] = g_strdup_printf ("%1.6f  ",  xyY[2]);
+          values[3] = g_strdup_printf ("%.01f %%", xyY[3] * 100.0);
         }
       break;
 
diff --git a/app/xcf/xcf-load.c b/app/xcf/xcf-load.c
index a7fc85e0d8..29ff1c1c2e 100644
--- a/app/xcf/xcf-load.c
+++ b/app/xcf/xcf-load.c
@@ -820,6 +820,9 @@ xcf_load_image_props (XcfInfo   *info,
                 GIMP_LOG (XCF, "prop sample point x=%d y=%d mode=%d",
                           x, y, pick_mode);
 
+                if (pick_mode > GIMP_COLOR_PICK_MODE_LAST)
+                  pick_mode = GIMP_COLOR_PICK_MODE_PIXEL;
+
                 sample_point = gimp_image_add_sample_point_at_pos (image,
                                                                    x, y, FALSE);
                 gimp_image_set_sample_point_pick_mode (image, sample_point,