1. To skip frames the gs plugin ignors processing for skipped frames, thats it.
2. There is already an fps threshold option in there.
no, the frame skipping in pcsx2 tells the gs plugin (Gsdx) not to process the frames that are being skipped.
04-04-2013, 02:28 AM
(This post was last modified: 04-04-2013, 02:30 AM by nosisab Ken Keleh.)
In PC there is nothing or at least not much in between the CPU and the GPU, so the application/game writes specific logic for the CPU to chew and the bulk of graphics (read vector calculation) directly to the GPU. Where this is an exception in newer games, like Skyrim which was ported from consoles where the CPU is "stronger" than the GPU, the general performance is hit hard.
That's not the case of PS2 which has the CPU (EE), the two vector units (VU), an interface to GS and finally GS itself. Much of the work made by the VUs falls on the CPU "shoulders" and the CPU simply don't have enough vector unities to deal with the load that normally goes to the GPU. Nowadays EE and VUs are shoved inside the same chip (what may lead some to think they are one and only CPU with extended vector processing capacity) but this does not change that x86 CPUs just lack enough float point unities to deal with the load coming from the PS2 game's code. multithreading the VU (MTVU) is an attempt to reduce the problem but can't really solve it. The GPU is the piece having a lot of vector unities to deal with this tipe of calculation, any reasonably video card would chew it relatively easy, as already stated, that's how it's done in PC.
PCSX2 already has many optimizations, out of order execution and branch prediction, state of art micro recompilers which do wonders in foreseeing the possible blocks of code coming from the game and everybody is happy... till a game's developer finds out ways to code the game in a way that just kill the prediction, causing lots of misses and massively harming the general performance.
Someday the methods and approaches may be reviewed and rewritten to get "real", actual performance boost, just they aren't things to be done in a day's job. Changes in any those things ask for deep rewrite in many modules to be properly implemented if ever will. Insisting in proposing methods which changes the structure of PS2 (notice it's not a typo, I meant PS2 indeed) is not the way to go. The intention is getting the emulators more accurate and compatible at each revision and version... not going by the road of killing all that was already accomplished in compatibility and accuracy.
Points to ponder.
Imagination is where we are truly real