It took some effort, but I managed to compile SDL Frotz, the version with graphics. @DavidG has applied my updates to Frotz’s documention, and I’ve also filed a PR to update the Homebrew formula for Frotz, to make it install the SDL version.
So probably in a week or so you can just
brew install frotz (or
brew upgrade frotz if you already have it installed) and you’ll get a working copy of SDL Frotz.
If you’re feeling impatient, here’s what I did.
I installed Xcode 11.4.1 from the Mac App Store on macOS Catalina 10.15.4, installed Homebrew from its setup script, and then I ran this command to install all required dependencies.
brew install libao libmodplug libsamplerate libsndfile libvorbis \
pkg-config sdl2 sdl2_mixer freetype libpng jpeg zlib
With that done, I checked out the latest version of Frotz from Gitlab (which has build fixes not available in the latest
frotz-2.51 release), and I ran
make all. That builds a binary
sfrotz in the current directory. I was then able to run
./sfrotz ~/Downloads/shogun/shogun.ZIP, which, since it appeared alongside
shogun.blb, was able to load and display images.