Handle image being smaller than outline layer

Author: tailoric

script-fu-outline.scm

@@ -1,22 +1,24 @@
 (script-fu-register 
-    "script-fu-outline"                                         ; func name
-    "Outline Current Layer..."                                  ; menu label
+    "script-fu-outline"                                         ;; func name
+    "Outline Current Layer..."                                  ;; menu label
     "Creates a simple outline for the current layer"
-    "Eric Schneider"                                            ; copyright notice   
+    "Eric Schneider"                                            ;; copyright notice   
     "2019 Eric Schneider"
-    "September 07, 2019 "                                       ; date created
-    "RGBA"                                                      ; image type that the script works on
+    "September 07, 2019 "                                       ;; date created
+    "RGBA"                                                      ;; image type that the script works on
     SF-IMAGE        "Image"         0
     SF-DRAWABLE     "Drawable"      0
-    SF-ADJUSTMENT   "Border Size"   '(2 1 1000 1 5 0 1)         ; a spin button
-    SF-COLOR        "Color"         '(0 0 0)                    ; color variable
-    SF-TOGGLE       "Merge with Layer?" FALSE                   ; toggle if the layer should get merged with the outline
+    SF-ADJUSTMENT   "Border Size"   '(2 1 1000 1 5 0 1)         ;; a spin button
+    SF-COLOR        "Color"         '(0 0 0)                    ;; color variable
+    SF-TOGGLE       "Merge with Layer?" FALSE                   ;; toggle if the layer should get 
+                                                                ;; merged with the outline
 )
 (script-fu-menu-register "script-fu-outline" "<Image>/Edit")
 (define (script-fu-outline inImage inLayer inBorderSize inBorderColor doMergeWitLayer)
   (let* (        
             (inLayerName (car (gimp-item-get-name inLayer)))
-            (currentForegroundColor (car (gimp-context-get-foreground))) ;get the current foreground color to reset later
+            (currentForegroundColor (car (gimp-context-get-foreground)))    ;;get the current foreground 
+                                                                            ;;color to reset later
             (borderLayerHeight (+ (car (gimp-drawable-height inLayer)) inBorderSize))
             (borderLayerWidth (+ (car (gimp-drawable-width inLayer)) inBorderSize))
             (borderLayerPosition (+ (car (gimp-image-get-item-position inImage inLayer) ) 1))
@@ -32,8 +34,8 @@
                                 LAYER-MODE-NORMAL-LEGACY)))
         )
         (gimp-image-undo-group-start inImage)
-        (gimp-selection-clear inImage);remove current selection if there
-        ;initialize the border layer
+        (gimp-selection-none inImage) ;; remove current selection if there is any
+        ;;; initialize the border layer
         (gimp-image-add-layer inImage theBorderLayer borderLayerPosition)
         (gimp-layer-set-offsets 
           theBorderLayer 
@@ -46,8 +48,33 @@
           (+ borderLayerHeight inBorderSize) 
           inBorderSize 
           inBorderSize)
+        ;;; Handle the case of the image being smaller than the layer + outline size
+        (let*
+          (
+            (imageHeight (car(gimp-image-height inImage)))
+            (imageWidth (car(gimp-image-width inImage)))
+            (sizeDiffHeight (- borderLayerHeight imageHeight))
+            (sizeDiffWidth (- borderLayerWidth imageWidth))
+          )
+            (when (< imageHeight borderLayerHeight)
+                     (gimp-image-resize 
+                       inImage 
+                       imageWidth 
+                       (+ imageHeight (* sizeDiffHeight 2))
+                       0 
+                       sizeDiffHeight)
+                     (set! imageHeight (car(gimp-image-height inImage))))   ;; if we are increasing the height 
+                                                                            ;; we need to save the new size
+            (when (< imageWidth borderLayerWidth)
+                     (gimp-image-resize 
+                       inImage 
+                       (+ imageWidth (* sizeDiffWidth 2))
+                       imageHeight 
+                       sizeDiffWidth 
+                       0 ) )
+        )
         (plug-in-colortoalpha RUN-NONINTERACTIVE inImage theBorderLayer '(0 0 0))
-        ;select the outline of the current layer
+        ;;; select the outline of the current layer
         (gimp-image-select-item inImage CHANNEL-OP-ADD inLayer)
         (gimp-selection-grow inImage inBorderSize)
         (gimp-context-set-foreground inBorderColor)
@@ -60,14 +87,15 @@
           TRUE
           0
           0)
-        (gimp-context-set-foreground currentForegroundColor)
-        (gimp-selection-clear inImage)
         (when (equal? doMergeWitLayer TRUE) 
               (gimp-image-merge-down
                 inImage
                 inLayer
                 CLIP-TO-BOTTOM-LAYER)
         )
+        ;;; reset everything that is resettable to the state before
+        (gimp-context-set-foreground currentForegroundColor)
+        (gimp-selection-none inImage)
         (gimp-displays-flush)
         (gimp-image-undo-group-end inImage)
    )