Corrected integer conversion problems in `brighten`
treec0e6abc538b32c4ff0a8e8a16885129bfeeaee39
drwxr-xr-x - .github
-rw-r--r-- 470 .gitignore
-rw-r--r-- 0 .gitmodules
-rw-r--r-- 1367 3rdparty.txt
-rw-r--r-- 1565 LICENSE.txt
-rw-r--r-- 8404 README.md
drwxr-xr-x - assets
drwxr-xr-x - docs
-rw-r--r-- 1188 dub.json
drwxr-xr-x - src
-rw-r--r-- 1185 thanks.txt