Brewology

In my long-overdue update on Thursday I explained how some of the work I've been doing on the dynarec engine has produced a significant speedup. This post will give a few numbers to give an idea of what you can expect in R9.

The table below shows the framerate for various scenes in R8 with a column showing the framerate for the build I'm currently testing effectively R9). The final column shows the relative speedup:

Scene R8 framerate Current framerate Speedup
Mario Head 8 12 x1.5
Mario Menu 38 52 x1.4
Peach Letter 18 25 x1.4
Mario Ingame 18 24 x1.3
Zelda OoT Title 8 13 x1.6
Zelda OoT Menu 39 55 x1.4
Zelda OoT Ingame 1 6 10 x1.7
Zelda OoT Ingame 2 5 9 x1.8
Starfox Intro 21 27 x1.3
Starfox Title 9 11 x1.2
Starfox Training 17 23 x1.4
Mariokart Title 16 33 x2.1
Mariokart Menu 12 24 x2.0
Mariokart Ingame 12 20 x1.7
Spiderman Title 22 35 x1.6
Spiderman Menu 21 27 x1.3
Spiderman Ingame 10 18 x1.8
Quest64 Title 75 90 x1.2
Quest64 Ingame 1 20 25 x1.3
Quest64 Ingame 2 21 29 x1.4


Clearly there's a significant improvement in framerate. On average, games are running about 40% faster, but in many cases the framerate has almost doubled. Subjectively, the difference means that many games are feeling a lot more responsive and playable now. Anything over 20fps 'feels' pretty good, but my long-term goal is to get this up to 30fps for as many titles as possible.

I noticed a couple of interesting differences between the two builds when running the tests, and you can see some of these in the new screenshots. Firstly, notice that the shadows in Super Mario 64 are all nice and round. This is due to the 'mirrored texture support' that I mentioned in Thursday's update (this also fixes the star that opens over Mario's head in the title sequence).

Secondly, the jerky/shaky screen that was affecting Mario Kart 64 now seems to be fixed. I'm not quite sure what was causing this, but I'm glad it's fixed Smiley

Next, notice that the text is Quest 64 is now fixed. In R8 this was horribly corrupted. This is due to the fixing a few texture conversion bugs as I was introducing proper support for 16 bit textures.

Finally, the texture on the floor in Quest 64 is now fixed. Again, I'm not totally sure what change is responsible for this, but it's nice to see it working correctly.

One final thing to note is that these figures were obtained by running the emulator with 'optimal' settings. For the current build, this includes disabling audio output. I'll talk a bit about audio support soon, including a bit about its impact on performance.

-StrmnNrmn