This commit integrates the bitmap font in the resource system, so
that cross-compilation would be easier.
The font handling code was carefully written to do glyph parsing
lazily; in practice this means that after this commit, startup
is less than 25ms slower, most of it spent in inflate().
This should also result in faster rendering, since there is no
rampant plane switching anymore; instead, all characters that are
actually used are stashed into same one texture.
This commit integrates icons in the resource system so that they
can be loaded (or reloaded, without restarting) in @2x mode, which
will be added in a future commit. png2c is no longer necessary.
png2c used to perform the following transformation:
if(r + g + b < 11) r = g = b = 11;
This is now achieved by switching the icons to RGBA mode and adding
alpha channel with the following imagemagick invocation, which is
equivalent to the transformation above:
for i in *.png; do
convert -fuzz 4% -channel rgba -matte \
-fill "rgba(255,255,255,0)" -opaque black \
$i $i
done
The Debian package solvespace now includes /usr/share/solvespace;
this should be split out into solvespace-data later.
This font is less complete than our bitmap font, Unifont: Unifont
has essentially complete Unicode coverage and LibreCAD's font only
has Latin, Cyrillic and Japanese, but it can be extended rather
easily, so this should be fine for now.
These embedded fonts fatten glhelper.o quite a bit:
bitmapfont.table.h is about 8M in gzip-compressed bitmaps and
vectorfont.table.h is about 2M in raw vector data.
In spite of that it takes just around five seconds to build
glhelper.c on my laptop, so it should be fine.
The final executable grows from about 2M to about 8M, but this
is a small price to pay for fairly extensive i18n support.
The new font has somewhat different metrics, so the rendering
code has been fudged to make it look good.
After this change, SolveSpace does not contain nonfree assets.
Additionally, Perl is not required for the build.
Note that in the US, case law suggests that copyright does
not apply to bitmap fonts:
http://www.renpy.org/wiki/renpy/misc/Bitmap_Fonts_and_Copyright
Nevertheless, it was prudent to replace the asset with something
that is unambiguously free.
As a side effect, zlib and libpng are now git submodules,
based on their respective official git repositories.
This is necessary, because MinGW has a different ABI and
it cannot use the prebuilt binaries built by MSVC.
The submodules are also used for Windows, for several reasons:
* to allow 64-bit builds;
* to allow using newer MSVC, which doesn't like the prebuilt
libraries;
* to keep the libraries updated.
