emkay Posted November 4, 2011 Author Share Posted November 4, 2011 Hi there! Mathy told me of this thread. I'm the narrator in this video an I have some comments: 1. The Nickname "Rockford" is a nickname I use in another forum (Abbuc.de). I am not ( and never was) the "Rockford" here on AtariAge. I am an A8 user and not an C64 user. I never owned an C64. Ahh, OK Hab mich schon gewundert. 2. The explanations are based on a discussion before the begin of this video. Most of the others in the room were C64 user and we talked about the differences between sprites and player-missile graphic. By mistake I took over the "sprites" in my mind while making the presentation. Later I noticed this confusion, but then the video was done and online (I did not put it on youtube). After all, it made it more understandable for the C64 guys. Das Problem dabei ist, wenn man die technischen Details so beschreibt, wird nicht klar, dass die Technik hinter den beiden Computern einfach komplett anders ist. Hier ist es nicht die "Sprite Technik" , die irgendwie Objekte beschleuningt, sondern das Zusammenspiel von CPU, ANTIC(als Coprozessor) und GTIA . 3. For the presentation used the old demo, because I didn't had a 8MB cart for the final version. I showed it on a real A8 (130XE). 4. Heaven/TGA: Jepp, ich bin Schwabe. Heidenei , a Schwob A short summary of the spoken text: I explained, how yout get more than one color for the player (the unlucky "sprite" discussion...), about the speed in this game (this ist the part when an C64 user asked the funny question if it is higher clocked than normal), and about the limitations in colors (this is the part when a C64 user said the C64 version has more colors - Later I saw the C64 version, it has not more colors). C64 has 16 colours only After all the main idea was presenting new games for the A8, but it ended as an discussion about system differences, as always. Because of this I didn't even talked about the history of Space Harrier, about the original programmers and so on. Now I understand the polite talk of you Quote Link to comment Share on other sites More sharing options...
sack-c0s Posted November 4, 2011 Share Posted November 4, 2011 http://www.youtube.com/watch?v=xeHm30hty98 That's a really odd mix considering the graphics quality and the sound The PC version just looks like a crappy port. Here's the ST version. A machine with a lower clock speed, hindered by having to fiddle with bitplanes and has a squarewave sound chip. Should be just as bad, right? Nope. The spectrum version I have an odd respect for - it looks garish because the colours on that machine are very saturated and clash quite badly, but having just written a speccy game I've got a lot of respect for the speed of the thing. It looks quite playable actually 1 Quote Link to comment Share on other sites More sharing options...
Sheddy Posted November 4, 2011 Share Posted November 4, 2011 The spectrum version I have an odd respect for - it looks garish because the colours on that machine are very saturated and clash quite badly, but having just written a speccy game I've got a lot of respect for the speed of the thing. It looks quite playable actually http://www.youtube.com/watch?v=VmLMBlvyPZI Me too. That grid is spot on, as is the left/right "scroll" of it and stuff on the ground - same as arcade (atari one is just simple 3d parallax as I couldn't figure out what algorithm/transforms are going on in the original) This is my favourite version though, when anyone asks why I didn't use GTIA modes http://www.youtube.com/watch?v=cs-4Zu0DN2g&feature=related Quote Link to comment Share on other sites More sharing options...
emkay Posted November 4, 2011 Author Share Posted November 4, 2011 http://www.youtube.com/watch?v=xeHm30hty98 That's a really odd mix considering the graphics quality and the sound The PC version just looks like a crappy port. Here's the ST version. A machine with a lower clock speed, hindered by having to fiddle with bitplanes and has a squarewave sound chip. Should be just as bad, right? http://www.youtube.com/watch?v=VYmQDr5JWvg Nope. ST has no slow interface between the main CPU/RAM and the graphics device. ISA Bus was very slow. Quote Link to comment Share on other sites More sharing options...
emkay Posted November 4, 2011 Author Share Posted November 4, 2011 This is my favourite version though, when anyone asks why I didn't use GTIA modes http://www.youtube.com/watch?v=cs-4Zu0DN2g&feature=related Having something in mind But, GTIA mode would have suited "ok-ish". This thing uses charmode resolution, GTIA has the double resolution to offer. Quote Link to comment Share on other sites More sharing options...
emkay Posted November 4, 2011 Author Share Posted November 4, 2011 Couldn't resist GTIA resolution and Atari palette... mockup 1 Quote Link to comment Share on other sites More sharing options...
NRV Posted November 4, 2011 Share Posted November 4, 2011 This is my favourite version though, when anyone asks why I didn't use GTIA modes http://www.youtube.com/watch?v=cs-4Zu0DN2g&feature=related At least you have the option to shoot or to listen to the music 2 Quote Link to comment Share on other sites More sharing options...
Sheddy Posted November 5, 2011 Share Posted November 5, 2011 Sheddy, what could your engine handle on 64k machines? or 128k? Er, Space Harrier with a limited amount of enemy types in between loading? You'll have to be more specific with the question Quote Link to comment Share on other sites More sharing options...
NRV Posted November 5, 2011 Share Posted November 5, 2011 Sheddy, what could your engine handle on 64k machines? or 128k? Er, Space Harrier with a limited amount of enemy types in between loading? You'll have to be more specific with the question Hmmm maybe.. any of the current levels that could run in 128k or 64k? (I suppose different levels need different memory sizes), the bonus stage? a level without a boss fight? a level with only one type of enemy and some trees? Go to sleep .. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted November 5, 2011 Share Posted November 5, 2011 Sherry... I mean a more generic type of your engine. How many objects would fit into 64k? Quote Link to comment Share on other sites More sharing options...
oky2000 Posted November 5, 2011 Share Posted November 5, 2011 (edited) ST has no slow interface between the main CPU/RAM and the graphics device. ISA Bus was very slow. ISA = 8 or 11mhz 16bit bus. Edited November 5, 2011 by oky2000 Quote Link to comment Share on other sites More sharing options...
sack-c0s Posted November 5, 2011 Share Posted November 5, 2011 http://www.youtube.com/watch?v=xeHm30hty98 That's a really odd mix considering the graphics quality and the sound The PC version just looks like a crappy port. Here's the ST version. A machine with a lower clock speed, hindered by having to fiddle with bitplanes and has a squarewave sound chip. Should be just as bad, right? http://www.youtube.com/watch?v=VYmQDr5JWvg Nope. ST has no slow interface between the main CPU/RAM and the graphics device. ISA Bus was very slow. I'm aware that bus transfers are relatively slow (even today trying to minimize the amount you send over is a pretty big optimisation), but even taking that into account and looking at other 1989 PC games that is just nasty by comparison.... and you can't blame the ISA bus for the tuneless excuse for music but yeah - the more you look at some of these versions the more impressive the A8 version gets 1 Quote Link to comment Share on other sites More sharing options...
Rybags Posted November 5, 2011 Share Posted November 5, 2011 ST: 50% of cycles reserved for DMA = 8 million bytes/second left for the CPU. So, practically no difference - although ISA bus has to be shared with HDDs and other devices. ST screen = only 32,000 bytes to deal with, on the PC any half decent graphics mode was typically double that at least. But, history showed that the PC didn't really come into it's own against the Amiga and ST until the '386 era, so in effect we had a 25 MHz or faster full 32-bit CPU, sometimes with FPU assistance against an 8 MHz 16/32 bit one. Quote Link to comment Share on other sites More sharing options...
Sheddy Posted November 5, 2011 Share Posted November 5, 2011 Sherry... I mean a more generic type of your engine. How many objects would fit into 64k? It depends on each object's size and how complex the masking required for compiled sprites, so it varies a lot. There's a spreadsheet in the source code download "tools" folder with code size and CPU cycles for every object's pre-scaled and pre-shifted frames. EG: biggest frame size of "bush" takes 1449 bytes for 3640 cycles. Smallest frame is 33 bytes for 72 cycles. All 22 frames for fairly smooth movement take 7700 bytes. ...but biggest frame of "tree" takes 3186 bytes for 8070 cycles. Smallest frame is 79 bytes for 175 cycles. All frames are 17682 bytes! Using x register to hold repeat masks, biggest "tree" could be 3137 bytes for 8106 cycles. Not usually many repeat masks for small frames though Using a 4 colour screen instead of pseudo 16 colour screen would nearly halve those figures (and less screen memory needed too of course) and less need for ultimate speed Using "quite fast" sprite routines like demo version would give a lot more space for objects. On average, about 20 objects fitted into extra 64K of the 130XE. They were less complex than the ones above and only 4 colours each though. Can't remember exactly now, but nearly twice as many cycles were needed sometimes for similar object than the compiled sprite method. 1 Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted November 5, 2011 Share Posted November 5, 2011 oh... Chris... I was not aware that you have released the source code??? Quote Link to comment Share on other sites More sharing options...
Sheddy Posted November 5, 2011 Share Posted November 5, 2011 oh... Chris... I was not aware that you have released the source code??? yep check out the downloads section of my site Quote Link to comment Share on other sites More sharing options...
oky2000 Posted November 5, 2011 Share Posted November 5, 2011 If that video is from DOSBOX it would be slow too unless they increase the cycles to maximum but still EGA colours are crap.. Looking at PC games from the 80s you realise you have 2 options... Find it on MAME Find it for Amiga. Quote Link to comment Share on other sites More sharing options...
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