This is not a real fix and only prevents crash, textures IO might be not
working totally correct if they're unicode path or so. Proper solution
would be to detect which locale we can use and set LANG, LC_ALL and friends.
Each dpi value stores its own set of font sizes, so while dragging the
dpi value would collect many sizes and never free.
Also change how BLF_cache_clear works,
it was freeing memory but not the OpenGL textures.
Now just free all the cache and GL textures and let drawing allocate them again as needed.
Looks like this is has been there since the initial commit
of BLF.
The blf_dir_metrics_search was using the pointer to the
extension of the file and not the full path to check for
metrics files (.afm/.pfm).
Never notice before probably because is not common to use a font
with additional metrics files.
Apparently mingw/gcc is too stupid to recognise that the values
in alphatest will only be used if they're within the range of
unsigned char (i.e. 0 <= x < 255) when this is done using a ternary
operator. Then again, it's quite hard for humans to immediately
parse what is going on here either! Converting this clever code
back to a more obvious form that mere mortals (and compilers it
seems) can handle with ease ;)
Printing text on the color grid image would initialize font glyphs from a thread at
the same time as the UI, causing conflicts. The freetype glyph renderer needs to be
mutex locked because it uses a shared buffer internally even when rendering for
different fonts. Also needed to change the image generate function to use the render
monospace font to avoid conflicts in blenfont.
What's still weak in the blenfont API is that there is no distinction between a font
and a thread using that font to render with some particular size, style, etc.
After quite some time debugging going back through previous commits for this
feature and digging around the internals of the blenfont,I finally found the
culprit. It turns out that there was just a single line missing between
BLF_width_default() and BLF_width_and_height_default(), which caused the widths
returned to understimate the space required or so, causing text clipping. The
offending line probably correcting for different DPI scaling values.
