# Makefile for the Gallery images on the Sketch homepage
#

# All the gallery files are generated from pairs of sk-files and readme
# files. The rendering process involves relatively large intermediate
# PPM files which are not automatically removed. You may want to do that
# by hand occasionally.

# Directory where the .sk and .readme files can be found
SRCDIR = src

#
# Tools Configuration
# 

# program to convert .sk files to ppm
SK2PPM = sk2ppm

# program to convert ppm to jpeg
CJPEG = cjpeg

# program to scale a ppm file
PNMSCALE = pnmscale

# The Gallery images. These are the basenames of the .sk and .readme
# files in $(SRCDIR). They're grouped by artist with MISC as the catch
# all.
APASCUAL = coco nana portrait SimcaSP moniteur Affiche4 Distribution Simca8
WOJTKIEWICZ = bathead fruitscene kapelusznica
HARA = trem01 raposa
TATANE = avion cartes compo helicoptere photo pomme vache
BIDDIER = southern_bell southern_cop smile_n_jack under_da_sea
THILBRICHT = waratah
STOVICEK = stay_with_us anna04
MISC = bsddaemon penguin sun

# list of all drawing basenames to process
DRAWINGS = $(APASCUAL) $(WOJTKIEWICZ) $(HARA) $(TATANE) $(BIDDIER) \
	$(THILBRICHT) $(STOVICEK) $(MISC)

# list of all the tarfiles
TARFILES = $(DRAWINGS:%=%.tar.gz)
# list of all the jpg images
IMAGES = $(DRAWINGS:%=%.jpg)

# Resolution of the rendered .sk files in ppi
FULL_RESOLUTION = 144

# number of gradient steps when rendering
GRADIENT_STEPS = 100

# Command to scale the rendered PPM file to a more suitable size for the
# full image
FULL_SCALE = $(PNMSCALE) 0.4

# scale factor for the preview thumbnail
PREVIEW_FACTOR = -height 150

# cjpeg options for the full-scale images
LARGE_JPEG_OPTS = -quality 80

# Some images need some special options or extra processing. To
# facilitate this, the makefile uses variables with the form
# <basename>_sk2ppmopt and <basename>_previewfilter. <basename> is the
# basename of the sk-file being processed. 
#
# The *_sk2ppmopt variables control the rendering of sk-files to ppm.
# Normally, the bounding box of an image determines the region of the
# drawing that is rendered. If the *_sk2ppmopt variable's value is page,
# then the page is used as the region.
#
# The *_previewfilter are an additional filtering step for the generated
# previews. Their value should be a command that accepts a PPM file on
# stdin and writes a PPM file to stdout. The command should end in a
# pipe symbol. The output is the input to the cjpeg program which writes
# the preview image.
coco_sk2ppmopt = page
moniteur_previewfilter = pnmcrop -black |
coco_previewfilter = pnmcrop -black |
bathead_previewfilter = pnmcrop -black |


# the intermediate ppm files should not be removed automatically because
# they're relatively expensive to create.
.PRECIOUS: %.ppm

all: $(IMAGES) $(TARFILES)

%.jpg:	%.ppm
	$(PNMSCALE) $(PREVIEW_FACTOR) $< | $($*_previewfilter) \
	$(CJPEG) > small$@ \
		|| rm -f small$@
	$(FULL_SCALE) $< | $(CJPEG) $(LARGE_JPEG_OPTS) > $@ || rm -f $@

%.ppm:	$(SRCDIR)/%.sk
	$(SK2PPM) --resolution=$(FULL_RESOLUTION) \
	--gradient-steps=$(GRADIENT_STEPS) \
	$(shell if [ "$($*_sk2ppmopt)" == "page" ]; \
		then echo ''; else echo '--bbox'; fi) \
	$< $@

%.tar.gz: $(SRCDIR)/%.sk $(SRCDIR)/%.readme
	tar cvzf $@ $^



clean:
	rm -f $(IMAGES) $(IMAGES:%=small%) $(TARFILES)

clobber: clean
	rm -f *.ppm