rules/images.mk

   1 # This is free and unencumbered software released into the public
   2 # domain. To the extent possible under law, the author of this file
   3 # waives all copyright and related or neighboring rights to it.
   4
   5 $(call include-once.,programs.mk)
   6
   7 XCF2PNG ?= xcf2png
   8 ICONUTIL := $(call command-v,iconutil icnsutil)
   9
  10 PNGCRUSH ?= pngcrush
  11 PNGCRUSHFLAGS ?= -brute -blacken -reduce -q
  12 CRUSH.png ?= $(PNGCRUSH) $(PNGCRUSHFLAGS) -ow
  13
  14 %.png: %.xcf
  15         $(XCF2PNG) $< > $@
  16
  17 # First: xcf2png by default calls zcat rather than gzcat. This is
  18 # totally always broken; non-GNU zcat forces a .Z extension on its
  19 # input filename. So we can't rely on xcf2png's default behavior.
  20 # Luckily it offers -Z for a custom decompression program.
  21 #
  22 # BUT: When Gimp saves a .xcf.gz (and related formats), it doesn't
  23 # truncate the file, it just writes until it's done and closes, and
  24 # whatever data was after that, is still after that. This is terrible
  25 # because it means the file never shrinks, but it's still nominally a
  26 # valid gzip file, according to http://www.gzip.org/#faq8.
  27 #
  28 # BUT: The suggestion to use gzip -q in the FAQ doesn't work for
  29 # non-GNU gzip. It shuts up the 'warning,' yes, but it still exits
  30 # with status code 1 (not even 2, like GNU gzip does for all
  31 # warnings). It does write out the data perfectly well, at least.
  32 #
  33 # BUT (of course): The non-zero exit (somewhat reasonably) makes
  34 # xcf2png barf and die before writing anything even though it got all
  35 # the data it needs.
  36 #
  37 # So: 1) use gunzip, 2) manually feed it to xcf2png, 3) hope nothing
  38 # is set to die based on pipe status, 4) hope that if the xcf data is
  39 # truly busted xcf2png will do something helpful.
  40 %.png: %.xcf.gz
  41         gunzip -c $< | $(XCF2PNG) - > $@
  42
  43 # https://korewanetadesu.com/make-icons.html
  44 .SECONDEXPANSION:
  45 %.icns: %.iconset $$(wildcard $$(@D)/$$*.iconset/icon_*.png)
  46         $(ICONUTIL) -c icns -o $@ $<
  47
  48 %.ico: %.iconset $$(wildcard $$(@D)/$$*.iconset/icon_*[0-9].png)
  49         convert -background transparent -colors 256 $(filter-out $<,$^) $@
  50
  51 find-iconsets = $(shell find $1 -type d -name '*.iconset')
  52 find-xcfs = $(shell find $1 -type f -name '*.xcf.gz' -or -name '*.xcf')
  53
  54 iconset>icons = $(1:.iconset=.icns) $(1:.iconset=.ico)
  55 xcf>png = $(patsubst %.xcf,%.png,$(patsubst %.xcf.gz,%.xcf,$1))
  56
  57 pngcrush-stampprefix ?= $(stampprefix)
  58 pngcrush-stampify = $(1:%.png=$(pngcrush-stampprefix)%.png.crushed)
  59
  60 $(pngcrush-stampprefix)%.png.crushed: %.png
  61         $(MKDIR) $(@D)
  62         $(CRUSH.png) $<
  63         touch $@