Reduce duplicated code and build SDL_ttf

scripts/build-deps.sh

@@ -26,15 +26,26 @@ else
     exit 1
 fi
 
-# Remove the existing SDL2 library (but not SDL_ttf)
-find /usr/include/SDL2 -type f -not -name 'SDL_ttf.h' -delete
-rm -fv /usr/lib/*-linux-*/libSDL2-*
-rm -fv /usr/lib/*-linux-*/libSDL2.*
-rm -fv /usr/lib/*-linux-*/pkgconfig/sdl2.pc
-
+# Build and install our SDL2 build
+# Since we'll be linking statically, we need to use Libs.private instead of Libs, but
+# there's no way to tell QMake to use the Libs.private section, so we have to replace
+# Libs with Libs.private ourselves prior to installation.
 cd /opt/SDL2
 ./configure --enable-static --disable-shared --enable-video-kmsdrm
 make -j$(nproc)
+sed -i '/^Libs:/d' sdl2.pc
+sed -i 's/Libs.private:/Libs:/g' sdl2.pc
+cat sdl2.pc
+make install
+
+# Build and install SDL_ttf
+# For similar reasons to SDL2 above, we have to patch the pkgconfig file in order to
+# link with a static library.
+cd /opt/SDL_ttf
+./configure --enable-static --disable-shared
+make -j$(nproc)
+sed -i 's/-lSDL2_ttf/-lSDL2_ttf -lfreetype/g' SDL2_ttf.pc
+cat SDL2_ttf.pc
 make install
 
 cd /opt/FFmpeg