NEWS: Supermodel WIP Update (2012/01/16)

Happy New Year, fellow emulationistas! Here's to a great new year filled with emulation goodies!

Mac users will be pleased to hear that the SDL 1.2.15 pre-release fixes full screen mode (-fullscreen). R. Belmont has posted instructions at the Forum. Linux users running Ubuntu 11.10 who are still experiencing problems building v0.2a should re-download the source code from the Download page. A tiny fix to the Linux Makefile has been made. I didn't think it warranted a new release.

Over the holidays, Nik and I had a chance to do a little bit of work on Supermodel. I looked into the 3D graphics problems that plague many of the Step 2.x games (namely Harley Davidson, The Ocean Hunter, and Emergency Call Ambulance) but was unable to make any headway. I did manage to fix the missing geometry when playing mirrored tracks in Daytona 2 and Scud Race Plus. For those who were unaware of this neat Easter egg, holding down the Start button during the course select screen allows races to be run on horizontally-mirrored tracks. As it turns out, AM2's programmers cleverly reversed the X axis without needing to modify much else. Only a single transformation matrix is changed to flip the graphics. Because of the differences between how OpenGL and Model 3 perform back-face culling, flipping a single axis reverses the orientation of most polygons, causing them to be discarded by OpenGL. Now, Supermodel performs some extra calculations to determine which side of a polygon is the front side and the mirrored graphics seem to work fine.


Mirrored tracks in Daytona USA 2 and Scud Race Plus before (left) and after (right) back-face culling was fixed.

This also fixes the wheels in Dirt Devils but is not related to any of the other problems that occur in Step 2.x games, which are caused by their unusual scene graph layout.

Nik optimized how model look-up tables are cleared in the 3D engine, which is one reason for the infamous slow-downs in Daytona 2. He also added the optional ability to run all rendering in a separate thread, further enhancing performance on multi-core systems and eliminating the slow-downs on fast systems. I have not yet tested the performance in Spikeout, which suffers from a related problem, but I would expect it to have an effect there as well. Nik committed these changes to SVN today. For those running their own up-to-date builds, multi-threaded graphics are enabled by default and can currently only be disabled by setting GPUMultiThreaded to 0 in Supermodel.ini (recommended on slower systems or for those with fewer cores).

News Source: Here