app: add pass-through layer mode

Only add the enum-value/mode-info for now.  Pass-through mode
appears above normal mode, in the default group, for layer groups
only.

app/core/gimpimage.c

@@ -2374,6 +2374,7 @@ gimp_image_get_xcf_version (GimpImage    *image,
         case GIMP_LAYER_MODE_ERASE:
         case GIMP_LAYER_MODE_MERGE:
         case GIMP_LAYER_MODE_SPLIT:
+        case GIMP_LAYER_MODE_PASS_THROUGH:
           version = MAX (10, version);
           break;
 

app/operations/layer-modes/gimp-layer-modes.c

@@ -850,6 +850,17 @@ static const GimpLayerModeInfo layer_mode_infos[] =
     .composite_mode       = GIMP_LAYER_COMPOSITE_SRC_ATOP
   },
 
+  { GIMP_LAYER_MODE_PASS_THROUGH,
+
+    .op_name              = "gimp:replace",
+    .function             = gimp_operation_replace_process,
+    .flags                = GIMP_LAYER_MODE_FLAG_BLEND_SPACE_IMMUTABLE |
+                            GIMP_LAYER_MODE_FLAG_COMPOSITE_MODE_IMMUTABLE,
+    .context              = GIMP_LAYER_MODE_CONTEXT_GROUP,
+    .composite_mode       = GIMP_LAYER_COMPOSITE_SRC_OVER,
+    .composite_space      = GIMP_LAYER_COLOR_SPACE_RGB_LINEAR
+  },
+
   { GIMP_LAYER_MODE_REPLACE,
 
     .op_name              = "gimp:replace",
@@ -875,6 +886,10 @@ static const GimpLayerModeInfo layer_mode_infos[] =
 
 static const GimpLayerMode layer_mode_group_default[] =
 {
+  GIMP_LAYER_MODE_PASS_THROUGH,
+
+  GIMP_LAYER_MODE_SEPARATOR,
+
   GIMP_LAYER_MODE_NORMAL,
   GIMP_LAYER_MODE_REPLACE,
   GIMP_LAYER_MODE_DISSOLVE,
@@ -1123,6 +1138,10 @@ static const GimpLayerMode layer_mode_groups[][2] =
     [GIMP_LAYER_MODE_GROUP_LEGACY ] = -1
   },
 
+  { [GIMP_LAYER_MODE_GROUP_DEFAULT] = GIMP_LAYER_MODE_PASS_THROUGH,
+    [GIMP_LAYER_MODE_GROUP_LEGACY ] = -1,
+  },
+
   { [GIMP_LAYER_MODE_GROUP_DEFAULT] = GIMP_LAYER_MODE_REPLACE,
     [GIMP_LAYER_MODE_GROUP_LEGACY ] = -1
   },

app/operations/layer-modes/gimpoperationlayermode.c

@@ -2491,6 +2491,7 @@ gimp_layer_mode_get_blend_fun (GimpLayerMode mode)
     case GIMP_LAYER_MODE_ERASE:
     case GIMP_LAYER_MODE_MERGE:
     case GIMP_LAYER_MODE_SPLIT:
+    case GIMP_LAYER_MODE_PASS_THROUGH:
     case GIMP_LAYER_MODE_REPLACE:
     case GIMP_LAYER_MODE_ANTI_ERASE:
     case GIMP_LAYER_MODE_SEPARATOR: /* to stop GCC from complaining :P */

app/operations/operations-enums.c

@@ -142,6 +142,7 @@ gimp_layer_mode_get_type (void)
     { GIMP_LAYER_MODE_ERASE, "GIMP_LAYER_MODE_ERASE", "erase" },
     { GIMP_LAYER_MODE_MERGE, "GIMP_LAYER_MODE_MERGE", "merge" },
     { GIMP_LAYER_MODE_SPLIT, "GIMP_LAYER_MODE_SPLIT", "split" },
+    { GIMP_LAYER_MODE_PASS_THROUGH, "GIMP_LAYER_MODE_PASS_THROUGH", "pass-through" },
     { GIMP_LAYER_MODE_REPLACE, "GIMP_LAYER_MODE_REPLACE", "replace" },
     { GIMP_LAYER_MODE_ANTI_ERASE, "GIMP_LAYER_MODE_ANTI_ERASE", "anti-erase" },
     { 0, NULL, NULL }
@@ -210,6 +211,7 @@ gimp_layer_mode_get_type (void)
     { GIMP_LAYER_MODE_ERASE, NC_("layer-mode", "Erase"), NULL },
     { GIMP_LAYER_MODE_MERGE, NC_("layer-mode", "Merge"), NULL },
     { GIMP_LAYER_MODE_SPLIT, NC_("layer-mode", "Split"), NULL },
+    { GIMP_LAYER_MODE_PASS_THROUGH, NC_("layer-mode", "Pass through"), NULL },
     { GIMP_LAYER_MODE_REPLACE, NC_("layer-mode", "Replace"), NULL },
     { GIMP_LAYER_MODE_ANTI_ERASE, NC_("layer-mode", "Anti erase"), NULL },
     { 0, NULL, NULL }

app/operations/operations-enums.h

@@ -122,6 +122,7 @@ typedef enum
   GIMP_LAYER_MODE_ERASE,                 /*< desc="Erase"                    >*/
   GIMP_LAYER_MODE_MERGE,                 /*< desc="Merge"                    >*/
   GIMP_LAYER_MODE_SPLIT,                 /*< desc="Split"                    >*/
+  GIMP_LAYER_MODE_PASS_THROUGH,          /*< desc="Pass through"             >*/
 
   /*  Internal modes, not available to the PDB, must be kept at the end  */
   GIMP_LAYER_MODE_REPLACE,               /*< pdb-skip, desc="Replace"        >*/

libgimp/gimpenums.h

@@ -155,7 +155,8 @@ typedef enum
   GIMP_LAYER_MODE_COLOR_ERASE,
   GIMP_LAYER_MODE_ERASE,
   GIMP_LAYER_MODE_MERGE,
-  GIMP_LAYER_MODE_SPLIT
+  GIMP_LAYER_MODE_SPLIT,
+  GIMP_LAYER_MODE_PASS_THROUGH
 } GimpLayerMode;
 
 

tools/pdbgen/enums.pl

@@ -756,7 +756,8 @@ package Gimp::CodeGen::enums;
 			  GIMP_LAYER_MODE_LUMA_LIGHTEN_ONLY
 			  GIMP_LAYER_MODE_LUMINANCE
 			  GIMP_LAYER_MODE_COLOR_ERASE GIMP_LAYER_MODE_ERASE
-			  GIMP_LAYER_MODE_MERGE GIMP_LAYER_MODE_SPLIT) ],
+			  GIMP_LAYER_MODE_MERGE GIMP_LAYER_MODE_SPLIT
+			  GIMP_LAYER_MODE_PASS_THROUGH) ],
 	  mapping => { GIMP_LAYER_MODE_NORMAL_LEGACY => '0',
 		       GIMP_LAYER_MODE_DISSOLVE => '1',
 		       GIMP_LAYER_MODE_BEHIND_LEGACY => '2',
@@ -817,7 +818,8 @@ package Gimp::CodeGen::enums;
 		       GIMP_LAYER_MODE_COLOR_ERASE => '57',
 		       GIMP_LAYER_MODE_ERASE => '58',
 		       GIMP_LAYER_MODE_MERGE => '59',
-		       GIMP_LAYER_MODE_SPLIT => '60' }
+		       GIMP_LAYER_MODE_SPLIT => '60',
+		       GIMP_LAYER_MODE_PASS_THROUGH => '61' }
 	},
     GimpConvertDitherType =>
 	{ contig => 1,