Display transfers with the horizontal downscaling flag were calculating
the wrong output size, causing them to write double the amount of data
intended. It is likely that this was perceived as correct due to a
separate bug in calculating source indices which caused the image to be
padded unless the previous bug was present.
This fixes both issues, correcting flickering issues in 3dscraft,
blargSnes and more (caused by the transfer overwriting the back buffer
which followed) as well as potentially fixing other crashes.
Hardware testing determined that the GSP processes shared memory
framebuffer update info even when no memory transfer or filling GX
commands are used. They are now updated on every interrupt, which isn't
confirmed correct but matches hardware behaviour more closely.
This also reverts the hack introduced in #404. It made a few games
behave better, but I believe it's incorrect and also breaks other games.
PDC0 and PDC1 are both VBlank interrupts. PDC0 was being treated as a
HBlank interrupt and fired many more times than it should. They now both
fire together at 60 Hz. This puzzlingly *improves* apparent framerate on
many applications.
A few other interrupts were being fired inside the GSP command
processing instead of on the actual GPU register writes, so they were
moved there, which should cover direct writes tho those registers not
going through the GX command queue.
There is no documentation available on this function, but we set the result to false as a stub.
This allows Super Little Acorns to move all the way in game with pp3c.
Passing -pthread to GCC as a flag makes it both link to libpthread, and make C standard library routines reentrant. This makes the additional explicit links unnecessary.
Additionally, on OSX, this is the default behavior, and clang will print a message about it being unused if it's present there.
This both reduces redundancy in add_executable definitions, and makes it easier to link additional libraries. In particular, extra libraries are needed on OSX - see next commit.
