Path: chuka.playstation.co.uk!dialup-00-31.netcomuk.co.uk!user From: shad.dev@netcomuk.co.uk (Ira Rainey) Newsgroups: scee.yaroze.programming.3d_graphics Subject: Re: Video mode query Date: Wed, 18 Jun 1997 18:22:53 +0100 Organization: shadow developments Lines: 69 Message-ID: References: <33A7B3CA.771F@interactive.sony.com> NNTP-Posting-Host: dialup-00-31.netcomuk.co.uk X-newsreader: MT-NewsWatcher 2.2.2 In article <33A7B3CA.771F@interactive.sony.com>, N/A-Use-Newsgroup wrote: > From Ira (shad.dev @ netcomuk.co.uk) > > > >If I don't set a video mode at the start of my code (MODE_PAL > >or MODE_NTSC) then will the yaroze default to a particular mode > >or will it set itself to whatever it originally booted on? > > -- whenever you turn on power or reset the Yaroze, it will boot up > into NTSC. When you run programs and return to CIP, it should preserve > video mode, e.g. if you run program1 that sets mode pal, then you quit > program1 and return to CIP and run program2, it should stay in PAL > for program2 and carry on in PAL until SetVideoMode(MODE_NTSC) > is called or it is reset. So you say that my yaroze boots into NTSC? How come then when it boots and I run any code I write, without setting any video mode it runs in colour, but if I run some code that sets video mode to NTSC then it runs in B/W? I'm running my yaroze on a Commodore 1084S video monitor, which I beleive is not capable of running NTSC. > >I ask because if we are to distribute our finished game demos, then > >only those with the same TV systems as the writer would be able to use > >them properly. Hence no US or JAP demos. If I do not define my video > >mode as PAL and set my screen to 320x240 would it work ok on both sides > >of the pond? > > For a Yaroze game to work properly all over the world it is vital > that it DETECT video mode and run properly under either. > > Detecting video mode is just a question of testing the result of > GetVideoMode against MODE_PAL and MODE_NTSC. > > Making the game work properly under both modes is more tricky. > The main areas affected are screen resolution, VRAM layout, > overall frame rate and hence anything that depends on overall > frame rate (eg sound, speed of various game processes, etc). > > While it is typical for PlayStation games to use vertical > resolutions of 240/480 in NTSC and 256/512 in PAL, there is no > necessity for this; you can display 256/512 in NTSC (part of world > at top/bottom won't be shown) and you can display at 240/480 in PAL > (this results in a large black band at the bottom of the screen, but if > you set GsDISPENV.screen.y to e.g. 27 then the picture appears > centred with just the tiniest bands above and below). > > One main effect on VRAM is that NTSC games sometimes store small images > and CLUTs at the bottom-left of VRAM; this assumes that screen > resolution is not 256/512 i.e. is PAL-specific. Store nothing in the > areas of VRAM that are or may be taken up with draw/display buffering > and all should be fine. > > The other main effect of video mode is on frame rate, and this has > knock-on effects; how exactly this will affect your program is > hard to predict in advance, just try it and see what needs redoing. > > Lewis I write all my demos using 320x240 and the screen looks fine. I don't have a noticeable band over or below my screen. It's easier to run in 320x240 because the aspect ratio is the same as a regular PC screen, and it's easier to design layouts and graphics that way. Ira -- "The difference between the impossible and the possible lies in determination" -- Tommy Lasorda