Playing with Visual D's new mixed solution support

[Mike Parker via Digitalmars-d]

Every few years I do a little test to see how much effort it 
takes to get the ioquake3 [1] codebase set up in a way that I can 
replace bits of it with D implementations and compile it all 
together. Not because I plan to port the whole thing, but I'm 
perennially curious how difficult it would be for someone to get 
started on porting a complex C project to D piece by piece (the 
way it should be done). I have to say, Rainer has made it easier 
than ever on Windows with the new Visual D release [2].

So I generated a VS 2015 solution with the ioq3-premake-msvc 
project [3], loaded it up, compiled it all to make sure it works 
(ioq3 will find the Quake3 resources automatically if you have 
Quake3 installed via Steam). Then I added a D file, picked a 
function to reimplement in D, and built it again. This resulted 
in a handful of linker errors because the runtime isn't linked in 
automatically. Once I opened up the project properties and added 
the path to dmd2/windows/lib32mscoff to the linker directories 
and phobosm32mscoff.lib to the linker input, I had an instance of 
Quake3 running with a D implementation of Sys_Milliseconds [4].

As easy as that. No writing up custom build scripts, no manually 
adding D object files to the ioq3 project, or any of the other 
approaches I've taken in the past. Awesome! I think I'll do a 
write up on this for the D blog in the near future.

Great job, Rainer!

[1] https://ioquake3.org/
[2] http://forum.dlang.org/thread/oa3dp7$icu$1@digitalmars.com
[3] https://github.com/jpcy/ioq3-premake-msvc
[4] http://i.imgur.com/VP0ibfH.png