0.20250206: scheme: SUBTRACT-MODE

Author: zvezdochiot

scheme/resize-ris.scm

@@ -1,3 +1,29 @@
+;
+; (gimp-layer-set-mode layer-copy SCREEN-MODE)
+; NORMAL-MODE 0
+; DISSOLVE-MODE 1
+; BEHIND-MODE 2
+; MULTIPLY-MODE 3
+; SCREEN-MODE 4
+; OVERLAY-MODE 5
+; DIFFERENCE 6
+; ADDITION-MODE 7
+; SUBTRACT-MODE 8
+; DARKEN-ONLY-MODE 9
+; LIGHTEN-ONLY-MODE10
+; HUE-MODE 11
+; SATURATION-MODE 12
+; COLOR-MODE 13
+; VALUE-MODE 14
+; DIVIDE-MODE 15
+; DODGE-MODE 16
+; BURN-MODE 17
+; HARDLIGHT-MODE 18
+; SOFTLIGHT-MODE 19
+; GRAIN-EXTRACT-MODE 20
+; GRAIN-MERGE-MODE 21
+; COLOR-ERASE-MODE 12
+
 (define (resize-ris image 
                     drawable
                     newwidth
@@ -8,46 +34,37 @@
             (drawable  (car (gimp-image-active-drawable image)))
             (oldwidth  (car (gimp-image-width image)))
             (oldheight (car (gimp-image-height image)))
+            (layer-copy (car (gimp-layer-copy drawable TRUE)))
+            (layer-defect (car (gimp-layer-copy drawable TRUE)))
             (new-layer-1 (car (gimp-layer-copy drawable TRUE)))
             (new-layer-2 (car (gimp-layer-copy drawable TRUE)))
             (new-layer-3 (car (gimp-layer-copy drawable TRUE)))
         )
 
         (gimp-image-undo-group-start image)
 
-        (gimp-image-insert-layer image new-layer-1 0 -1)
-        (gimp-image-insert-layer image new-layer-2 0 -1)
-        (gimp-layer-set-mode new-layer-2 LAYER-MODE-MULTIPLY-LEGACY)
-        (set! new-layer-1 (car (gimp-image-merge-down image new-layer-2 EXPAND-AS-NECESSARY)))
+        (gimp-context-set-interpolation method)
 
-        (cond
-            ((= method 0)
-                (gimp-context-set-interpolation INTERPOLATION-CUBIC)
-            )
-            ((= method 1)
-                (gimp-context-set-interpolation INTERPOLATION-NONE)
-            )
-            ((= method 2)
-                (gimp-context-set-interpolation INTERPOLATION-LINEAR)
-            )
-            ((= method 3)
-                (gimp-context-set-interpolation INTERPOLATION-CUBIC)
-            )
-            ((= method 4)
-                (gimp-context-set-interpolation INTERPOLATION-NOHALO)
-            )
-            ((= method 5)
-                (gimp-context-set-interpolation INTERPOLATION-LOHALO)
-            )
-        )
+        (gimp-image-insert-layer image layer-copy 0 -1)
+        (gimp-image-insert-layer image layer-defect 0 -1)
+        (gimp-layer-scale layer-defect newwidth newheight TRUE)
+        (gimp-layer-scale layer-defect oldwidth oldheight TRUE)
 
+        (set! new-layer-1 (car (gimp-layer-copy layer-copy TRUE)))
+        (set! new-layer-2 (car (gimp-layer-copy layer-copy TRUE)))
+        (set! new-layer-3 (car (gimp-layer-copy layer-defect TRUE)))
+        (gimp-image-insert-layer image new-layer-1 0 -1)
+        (gimp-image-insert-layer image new-layer-2 0 -1)
         (gimp-image-insert-layer image new-layer-3 0 -1)
-        (gimp-layer-scale new-layer-3 newwidth newheight TRUE)
-        (gimp-layer-scale new-layer-3 oldwidth oldheight TRUE)
-
-        (gimp-layer-set-mode new-layer-3 LAYER-MODE-DIVIDE-LEGACY)
-        (set! new-layer-1 (car (gimp-image-merge-down image new-layer-3 EXPAND-AS-NECESSARY)))
-        (gimp-item-set-name new-layer-1 "RIS")
+        (gimp-layer-set-mode new-layer-1 SUBTRACT-MODE)
+        (set! layer-defect (car (gimp-image-merge-down image new-layer-1 EXPAND-AS-NECESSARY)))
+        (gimp-layer-set-mode new-layer-3 SUBTRACT-MODE)
+        (set! new-layer-2 (car (gimp-image-merge-down image new-layer-3 EXPAND-AS-NECESSARY)))
+        (gimp-layer-set-mode layer-defect SUBTRACT-MODE)
+        (set! layer-copy (car (gimp-image-merge-down image layer-defect EXPAND-AS-NECESSARY)))
+        (gimp-layer-set-mode new-layer-2 ADDITION-MODE)
+        (set! layer-copy (car (gimp-image-merge-down image new-layer-2 EXPAND-AS-NECESSARY)))
+        (gimp-item-set-name layer-copy "RIS")
 
         (gimp-image-scale image newwidth newheight)
 
@@ -62,13 +79,13 @@
                     "Resize used RIS (Reverse Interpolate Scale)"
                     "zvezdochiot https://github.com/zvezdochiot"
                     "This is free and unencumbered software released into the public domain."
-                    "2025-02-05"
+                    "2025-02-06"
                     "*"
                     SF-IMAGE       "Image"       0
                     SF-DRAWABLE    "Drawable"    0
                     SF-VALUE       "Width"       "1024"
                     SF-VALUE       "Height"      "1024"
-                    SF-OPTION      "Method"      '("Cubic" "None" "Linear" "Cubic" "NoHalo" "LowHalo")
+                    SF-ENUM        "Method"      '("InterpolationType" "cubic" "none" "linear" "cubic" "nohalo" "lohalo")
 )
 
 (script-fu-menu-register "resize-ris" "<Image>/Image/Transform")