Profiled, optimized libsnes builds for win32

I've been playing around with mingw, doing cross-compiles of libsnes with profile-guided optimizations (PGO) for use with SSNES in Windows and I think I've gotten it down pretty well.

I used the following C-flags at compile time:

-msse2 -fmerge-all-constants -fmodulo-sched -fgcse-sm -fgcse-las -funsafe-loop-optimizations -fsched-spec-load -fsched-spec-load-dangerous -fsched-stalled-insns=0 -fsched-stalled-insns-dep -fsched2-use-superblocks -fipa-pta -ftree-loop-linear -ftree-loop-im -ftree-loop-ivcanon -fivopts -fvariable-expansion-in-unroller -ffast-math -fbranch-target-load-optimize -maccumulate-outgoing-args -combine

This means it's only going to work on CPUs that support the SSE2 SIMD instructions, but that includes pretty much every processor manufactured in the past 8 years, so I figured that was good enough.

If you want to give them a try, you can get them from my mediafire.

Read More

Filter and Shader Stacking In SSNES

Themaister just added support for multipass shader application--a.k.a. shader stacking--to SSNES, his excellent (and recently GUI-fied) frontend for libsnes. His implementation includes some interesting and fancy options, including configurable scale factors for the first pass (i.e., the first shader). This allows hq2x to be scaled to its expected scale factor during the first pass and then scaled up again to fit the desired resolution, resulting in much better retention of detail (see this post for a side-by-side comparison of the two scaling methods). Additionally, we can use the second pass to stack a scanline shader on top of the resulting image, or even cgwg's CRT shaders:

As you can see, this combination greatly smooths out the jaggies and rounds the curves without blasting out all of the details, like hq2x can often do on its own.

This two-pass shader implementation also allows users to control the amount of bloom applied by a bloom shader in the first pass simply by modifying the scale factor. Here are two examples in which I've stacked blargg's NTSC filter, cgwg's CRT-Flat v3 shader, and Whateverman's simplebloom shader (rendered at 2x and 1x respectively):

In my opinion, this combination of bloom+CRT shaders+NTSC filter is exceptionally close to the Photoshop renders that inspired the CRT shader effort.

Windows binaries for this latest version of SSNES are available here, while Linux users can download deb binaries from my PPA repo. Mac users can also get in on the fun, but they'll have to compile everything themselves, as no one is providing Mac packages of SSNES yet.

As always, any shaders covered here are available in my mediafire account.

Read More

BSNES on Older Distros, such as Lucid and Squeeze

In addition to being on the forefront of SNES emulation, BSNES also utilizes cutting-edge programming techniques to maintain the cleanest, most easily readable code possible. Unfortunately, that means that older distros--even ones that are still well within their supported lifespan--may get left out in the cold.

However, BSNES forums user Themaister has done us all a favor and backported byuu's cutting-edge C++0x code to use the more widely supported C++98 standard, which allows it to be compiled on any version of GCC from 3.x on up. The only catch is that his work only applies to libsnes, the modular emulation core of BSNES in library form, so byuu's official Phoenix GUI is still off limits, as is his libsnes-driven Qt GUI.

Thankfully, Themaister has us covered here, too, by offering SSNES, his super-slim CLI-only interface to libsnes. Just like his C++98 port of libsnes, SSNES can be readily compiled with even extremely old versions of GCC, so any semi-modern distro should be able to use it just fine.

My PPA now contains Lucid packages for both libsnes (all three official cores, plus an snes9x-based core for legacy machines) and SSNES, which should also (hopefully) work on Debian Squeeze.

A few things I'd like to point out about SSNES:

1. It will accept a variety of audio drivers, including jack, which allows ultra-low latency :D

2. My package was built using dynamic libsnes linking, so it requires a libsnes package from my PPA to function

3. In addition to accepting BSNES-style XML shaders written in GLSL, SSNES will also accept shaders written in Nvidia's Cg language if you install the nvidia-cg-toolkit package

4. The default configuration file for SSNES is located at /etc/ssnes.cfg, but you can override this by placing another config file in ~/.config/ssnes

As always, let me know if you run into any problems with these packages.

Read More