automatically generate a GIMP-compatible palette file

Either `make gimp-palette` or `make doom.gpl` will convert the playpal
lump into a file that can be imported into GIMP for paletted image
modes.

.gitignore

@@ -15,6 +15,7 @@
 .\#*
 \#*\#
 wad*.txt
+doom.gpl
 
 # Per directory patterns to ignore. These do not apply recursively to
 # subdirectories. Each line should begin with "[!]/". Please keep the

Makefile

@@ -102,8 +102,14 @@ else
 	JSON=$(JSON) VERSION=$(VERSION) scripts/makejson
 endif
 
+doom.gpl: lumps/playpal/playpal-base.lmp
+	$(MAKE) -C lumps/playpal $@
+	mv lumps/playpal/$@ .
+
+gimp-palette: doom.gpl
+
 clean: wad-image-clean
-	$(RM) *.html $(OBJS) \
+	$(RM) *.html doom.gpl $(OBJS) \
 	      ./COPYING.txt ./CREDITS.txt \
 	      ./wadinfo_phase1.txt \
 	      ./wadinfo_phase2.txt \

lumps/playpal/Makefile

@@ -2,7 +2,11 @@ playpal.lmp: playpal-base.lmp playpal
 	./playpal playpal-base.lmp > playpal.lmp
 	cp playpal.lmp ../
 
+doom.gpl: playpal-base.lmp
+	./gen-gimp-palette
+
 clean:
 	$(RM) playpal.lmp ../playpal.lmp
+	$(RM) doom.gpl
 
 .PHONY: clean

lumps/playpal/README

@@ -13,3 +13,6 @@ The input for the script is playpal-base.lmp which contains the default
 palette seen during normal gameplay. The script translates this palette
 into the various other forms which are shown in different situations.
 
+There is additionally a “gen-gimp-palette” script that may be used to
+create a “doom.gpl” file suitable for importing into GIMP’s palette
+selection.

lumps/playpal/gen-gimp-palette

@@ -0,0 +1,14 @@
+#!/bin/sh
+
+# Generates a file suitable for importing into GIMP based on
+# playpal-base.lmp, and placed into doom.gpl
+
+# File header
+cat > doom.gpl <<EOF
+GIMP Palette
+Name: Doom
+Columns: 16
+#
+EOF
+
+od -An -w3 -tu1 playpal-base.lmp >> doom.gpl