From 383854430bc3b6b812d8e41ff5ab0e4ed77b0d48 Mon Sep 17 00:00:00 2001
From: Mike Swanson <mikeonthecomputer@gmail.com>
Date: Thu, 19 Sep 2019 15:17:52 -0700
Subject: [PATCH] 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                     |  1 +
 Makefile                       |  8 +++++++-
 lumps/playpal/Makefile         |  4 ++++
 lumps/playpal/README           |  3 +++
 lumps/playpal/gen-gimp-palette | 14 ++++++++++++++
 5 files changed, 29 insertions(+), 1 deletion(-)
 create mode 100755 lumps/playpal/gen-gimp-palette

diff --git a/.gitignore b/.gitignore
index cf9c2adb..f6497d32 100644
--- a/.gitignore
+++ b/.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
diff --git a/Makefile b/Makefile
index 891736c8..aa494e81 100644
--- a/Makefile
+++ b/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 \
diff --git a/lumps/playpal/Makefile b/lumps/playpal/Makefile
index b296de4c..14c01d47 100644
--- a/lumps/playpal/Makefile
+++ b/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
diff --git a/lumps/playpal/README b/lumps/playpal/README
index c3c12cdd..483c60d0 100644
--- a/lumps/playpal/README
+++ b/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.
diff --git a/lumps/playpal/gen-gimp-palette b/lumps/playpal/gen-gimp-palette
new file mode 100755
index 00000000..4423045a
--- /dev/null
+++ b/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