Path: chuka.playstation.co.uk!news From: Developer Support Newsgroups: scee.yaroze.programming.3d_graphics Subject: Video mode query Date: Wed, 18 Jun 1997 11:09:14 +0100 Organization: Sony Computer Entertainment Europe Lines: 53 Message-ID: <33A7B3CA.771F@interactive.sony.com> Reply-To: N/A-Use-Newsgroup NNTP-Posting-Host: 194.203.13.10 Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Mailer: Mozilla 3.01 (Win95; I) 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. >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? >Ira 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