Pete's OpenGL driver for PSX emus ---------------------------------- Some words from the first release in spring 1999: During development of PSSwitch I used some of the public PSEPro plugin sources to look how PSEPro communicates with the different plugins (especially the GPU drivers). After Version 1.0.12 of PSSwitch I wanted to write my own GPU, mainly because I was curious how the GPUs are working but also because the only real good GPU plugin (Lewpys Glide) could only be used by the owners of 3DFX cards. So I started to improve Duddie's SoftGPU, fixed some bugs and learned... until I noticed, that some important GPU parts were just missing and not even mentioned in the sources. I cried for help... and Lewpy jumped in... he gave me the informations I needed most, so my GPU could grow again... and it was slowing down speedwise. I had to make a decision: doing some high optimization stuff (but that's mostly a boring and very time-consuming job) or trying to use some kind of hardware acceleration (hey, that one sounds nice). OK, the decision was an easy one: "acceleration" should do the work, now-a-days video cards are "intelligent", so why don't use it? But what kind of interface should I use? Direct3D ? My aging MSVC 5.0 compiler just supported DirectX 3, the download of the DirectX 6 SDK from the internet would be >70MByte (and I have a slow connection to the net). And "NoComp" seemed to be working on a Direct3D GPU. Well, and Segu wasn't lazy, too... So I looked at the OpenGL API and it seemed to fit... and there were no "real" OpenGL GPUs for PSEPro, all, even the one from Kazz, were just partial implementations. I borrowed an OpenGL book from a friend (hi Gamma!) and got to work. Now I spent some weekends and evenings for getting it to work and after some ups and downs (in one of these downs I downloaded the DirectX 6.1 SDK and didn't want to do something with OpenGL at all in the future) I feel it is ready to hit the public. Enjoy! ---------------------------------------------------------------------------- Requirements: OpenGL... in Windows there should be a file called "opengl32.dll" in your Windows\System directory. That's the one I am using. If your video card supports OpenGL, the "opengl32.dll" will just be a mapper for the faster video driver functions, you don't have to install anything else. If you have a 3DFX add-on card (I have a Riva TNT/GeForce and a Voodoo II/III, so I could test both) and you want to use OpenGL with it, you should place the 3DFX "opengl32.dll" from the 3DFX OpenGL SDK in your PSEmu Pro directory, don't overwrite the original Microsoft dll in your System directory! You can get that SDK from the 3DFX server (www.3dfx.com), just search for "OpenGL SDK". Hint: Rename the "3dfxopengl.dll" into "opengl32.dll". Don't use a MiniGL driver for Quoke (had to rename that game from ID because I am a really dumb german grown-up and cannot make a difference between the screen and the reality, greetings to the german BPS) or alike, the right DLL should be > 600 KByte (MiniGL IS NOT OpenGL). If your video card has no OpenGL support, software emulation will be done from the Microsoft OpenGL32.dll, but that one is ssssslllloooooowwww. You can also give a "OpenGL to DirectX" mapper a try, there is one at www.altsoftware.com, just copy that "opengl32.dll" in your main emu directory. If you own a nVidia card, be sure to have installed the latest drivers (Detonator build), they are much faster than earlier versions. And, of course, try my D3D plugins, if your card is having OGL troubles :) ---------------------------------------------------------------------------- Configuration: Take yourself some time to test different settings (especially texture modes), because it seems every video card company has its own opinion what's important to speed up in OpenGL. Here is the list of the available settings and their baddies and gooddies... 1) Desktop resolution --------------------- Every time the GPU will be started in fullscreen mode, it will change the desktop to the chosen fullscreen size/color depth settings, after quitting the main emu your original Desktop will be restored. If your OpenGL driver doesn't support this feature (for example: older 3DFX OpenGL drivers) just select a proper resolution that fits your actual Desktop size, and your desktop's color depth. If your card supports OpenGL in window mode, you can give it a try. I prefer to play my games in fullscreen, but to do the coding in window mode :) The "keep psx aspect ratio" will insure, that the x/y ratios will be the same as on the real psx... use it, if you like it. 2) Texture handling ------------------- To optimize the texture storage, the plugin has to know the size of your gfx card vram. You can try to let the plugin auto-detect the available vram memory, or you can enter the right amount yourself (recommended on all non-nVidia cards). If you have a lotta vram (64 MByte or higher), you can also try the "Hi-Res texture (2xSaI)" or "Hi-Res texture (Scaled)" option. The 2xSaI one will use the superb 2xSaI algorithm from Derek Liauw (http://members.xoom.com/derek_liauw/) to improve the texture quality. For more informations check out the version notes from 10. July, 2002. The "Scaled" hires textures will need additionally some texture filtering (best: filtering mode 2) and a screen resolution of 800x600 or above. 3) Texture quality ------------------- Please see the 'version.txt' entry '1.May 1999' for details... * 'don't care' is how the versions minor 1.9 of my GPU were working, so selecting it means no gain and no loss... just to be sure. And of course it is the best solution for 3DFX OpenGL drivers at the time I am typing this text... * 'R4 G4 B4 A4': Every color info has 4 bits, so texture colors are not as fine, but speed is better with newer cards Don't use it with ATI cards, that mode is very slow with them. * 'R5 G5 B5 A1': texture colors are getting better, but the 'Alpha Multipass' mode can't be done with just one alpha bit. Many games don't need AM (Spyro, Tekken) so you can select this mode for better colors. This mode is the fastest one. * 'R8 G8 B8 A8': Best colors your PC can offer, at the cost of speed. If game speed is OK with that mode on your PC, use it! * 'B8 G8 R8 A8': Also best colors, but the different color ordering is giving a small speed up on some cards. See also the March 2003 release notes. 4) Bilinear filtering --------------------- Give it a try... the real PSX doesn't support BF, so there will be some glitches if you turn BF on. Several games will look nicer... there are two filtering modes... the Extended mode is slightly slower, but even better with most games. If you want you can also try both filtering modes without sprite filtering. Some game text will be much better readable, but some games will look weird if everything but sprites are smoothed... Or try the new "filtering with sprite smoothing"... that one is giving nice results most times :) 5) Framerate limit/Frame skipping --------------------------------- You can activate FPS limitation if your game is running to fast. You can use "Auto detect FPS limit", if you are not sure, what limit would be best to use or just type in a FPS rate. PAL games use 50 FPS, non-PAL games 60 FPS. And if things are getting too slow... you can try Frame skipping. Tip: to get the 'right' speed you should enable skipping and limitation together. You can also enable the in-game menu right from the game start (showing the fps and let you change some gpu options while playing). Of course you still can use the "DEL" key for showing/hiding the menu. Btw, all gpu hotkeys are described below. If you want to change the keys, you can use the small "..." button. 6) Offscreen Drawing --------------------- There are now (1.48 or newer) 5 different OD modes... OD is used to detect drawings which are outside the front/backbuffer, doing such stuff in software (or by tweaking polygon coords). 0 (none): fastest mode, glitches in splash screens/game gfx can happen 1 (minimum): takes care of most splash screens 2 (standard): does an easy check, if software drawing/coord tweaking is needed 3 (enhanced): does a more complicated check for soft drawing 4 (extended): does the "enhanced" check, and adds some additional buffer swap (can cause flickering with some games) 7) Framebuffer texture ---------------------- To get whirling screen effects and psx motion blurring, there are two ways to go: a) set framebuffer textures to emulated vram, enable full vram primitives (framebuffer access option) and offscreen drawing or b) disable full vram primitives and set framebuffer textures to 'gfx card buffer' or c) use 'gfx card buffer & software'. (a) will work on every system, but it will be very slow. (b) will prolly work only with certain gfx cards with a good speed (GeForce :)... (c) is kinda a compromise: there will be little gfx card accessing (good for slower gfx cards), and more software drawing instead (which will need some cpu power). btw, some games will work better/faster with (b), others may need (c) instead. You have to try that for yourself :) Well, ppl with slower cpus and/or gfx cards can use "black framebuffer textures", this option will be very fast, but, of course, the special effect will not appear! 8) Framebuffer access --------------------- Sometimes the real psx is reading/moving the already drawn display to make special effects. Again depending on your hardware and the game you want to play you may need to set one of the available options to get all effects. The highest setting (Full software drawing) will cause the internal soft gpu to paint every polygon, etc. ...
mrysiu0