EricBall

Well I finally finished Half Life 2 after an 18 month hiatus. Unfortunately the last third was much like the middle third. There's some frantic battles but no new weapons (until the final chapter) or puzzles. You do get the opportunity to take down some Striders, but only if you have an infinite supply of rockets. Otherwise it's a slog along the linear path trying to preserve health and ammo until the next resupply point. Oh, it turns out there are some areas with infinite enemies. So if you hang back and try to eliminate the opposition from cover you will eventually run out of ammo and/or take fatal damage. So you either have to dash from one safe area to the exit, or dash into danger (which then shuts down the enemy generator). In the final chapter you finally get a super gravity gun which can pick up your enemies. But rather than flailing around like they do in Force Unleashed, they turn into rag dolls - dead even before they are thrown into their comrades. I'm now debating whether to play through Episode 1 & 2.

What's the consequences of dropping your audio buffer to 1K?

One line drawing algorithm I learned from T.A. Goldthorpe dx = x1 - x0 dy = y1 - y0 qx = abs(dy) // note the reversal qy = abs(dx) q = min( qx, qy ) cx = x0 cy = y0 do plot( cx, cy ) qx = qx - q if ( qx < 0 ) qx = qx + abs(dy) cx = cx + sgn(dx) endif qy = qy - q if ( qy < 0 ) qy = qy + abs(dx) cy = cy + sgn(dy) endif while ( cx != x1 && cy != y1 ) plot( cx, cy ) Note: this is from memory / off the top of my head. I remember the basic idea, but have to work out the details anew each time I want to use it. Another line drawing algorithm I created myself was recursive binary subdivision.

For console developers, passwords make a lot of sense. It allows a player to "save" without having to put any non-volatile storage in the cartridge (not possible with a disc-based system) or require the player to have a memory pack. These days it's less of an issue as the cost of flash is fairly low (for cartridge systems) and most consoles have built-in storage. The problem with passwords is they can only express so much information. One per level is easy, but is the game tries to encode more (i.e. life count / score) the password gets longer and players are tempted to "crack" it to do things like give themselves more lives.

But Flick being bland was part of the movie. He was the "nerd ant", always the outsider, with big dreams but problems executing them. Sent on a quest to get him out of the way, if not killed. Sure he doesn't have the same charisma as Woody or Buzz, but I'm not sure the story would have made sense if he was.

Having slower cars start first also leads to more excitements as the faster cars have to pass them.

I'll have to disagree with you on Bugs Life, Wall-E and Up. But I will say that ever since I started seeing ads for Cars2 I just couldn't see going to see it. However, now that you've explained that it's a Mater Tall Tale (not that I've watched those), it makes more sense. But I'm still not tempted to buy a ticket. I'll wait until it hits one of the OTA networks.

Yes, and the world is moving in that direction. However there are problems with that strategy: 1. The bigger the game the harder it is to make it a download due to local storage requirements, download speed & caps. 2. Server-side outages lead to lost sales - see the recent PSN outage for examples. 3. Consoles are often sold by stores with very little markup with the difference made up by new game and, increasingly, used game sales. Downloadable only games would likely mean the console would have to be sold at a higher MSRP. See PSP-Go for an example.

As part of the "Welcome back" program Sony has given every PSN user a free month of PlayStation Plus - which gives discounts on downloadable content and some exclusive content. Well, I activated my free month and proceeded to download as much free stuff as I could, including several full games (including Oddworld Exodus). They might only last the month but they're free. Then last week Magic the Gathering: Duels of the Planeswalkers was added as a free download for Plus. I played Magic over a decade ago; spending many a Saturday or Sunday drinking beer at the local pub and playing Magic. And the game plays pretty much like I remember. Yes, it lacks the collection and deck building aspect of the physical game, but I don't think beginners could do much better than the included decks. I'm not sure I'm going to try the online competition; even with known decks my skills probably are nowhere close to those who have been playing since it was released. However, WotC just released MtG:DotP 2012 and I'm giving some serious thought to picking it up. (For $10 how can I say no?) Which got me to thinking - did WotC make MtG:DotP a free Plus download as a kind of time limited advertisement for 2012 for all PSN users or was it just a coincidence? Just like Magic, winning is a combination of good luck and tactics.

Remember that Qix was an arcade game from 1981, and arcade games aren't known for being easy or fair.

There's a free Angry Birds beta available via the Chrome App Store. I've played through the first 21 screens and I can't understand why it's so popular. This isn't to say that I don't enjoy it. I certainly had fun with this physics/puzzle game. But I also found the gameplay somewhat frustrating, and my tolerance and patience for failure is reasonably high. Thus, I imagine that most people would find the game very frustrating (confirmed by my wife), thus I am puzzled by why it's popular. The problem, IMHO, is the game asks the player to do two tasks: Determine the "right" place for the bird to hit to kill the pigs. Pull the slingshot back correctly to hit the desired target. (With the additional timing requirements for some of the birds.) Unlike some other parabolic arc firing games I've played, Angry Birds doesn't give the player any help in determining #2 for the first shot. Yes, you can refine your later shots base on the previous one, but that doesn't help with that first, often critical shot. And that's a problem. Because unlike a game like Worms where a mis-aimed shot typically has no negative impact, with Angry Birds that first shot can often cause the structure to collapse in such a way that it's significantly more difficult, if not impossible, to kill the pigs using the remaining shots. So, in order to be successful you have to accomplish both #1 and #2 on the first shot with no aids to assist with either. Difficult? Yes. Frustrating? You betcha. I also can't imagine trying to play the game on an iTouch/iPhone with the level of accuracy required with the slingshot (unless it's really zoomed in compared to the WebGL version).

This is probably only of interest to potatohead, but I don't want to depress the Propeller crowd. The Parallax Propeller is a pretty cool chip. Eight 32 bit cores running at 80+MHz with video output capabilities. A lot of people have said, that's cool let's make an emulator or videogames! Except that ain't easy. Yes, the Prop has enough processing power to emulate an 8 bit CPU at a reasonable speed except... There's no external memory bus, so you only have 32K of RAM for everything.* Getting a working CPU emulator is easy, a cycle accurate one is much harder. Emulating the CPU interaction with other chips is hard, and cycle accurate is harder. Emulating a video processor, even ones from the 8 bit era, is damn difficult. *Sure you can hook up an external memory, flash, eeprom, or SD card to the Prop. They all work great for bulk storage but are to slow for RAM/ROM emulation. The other problem is there's really no point. Sure it would be neat to hook a Prop up to a TV and play 2600 games using it. But a PC can already run emulators for anything in the 8 bit and 16 bit generations. So can some consoles. Thus I'm just seeing the real advantage of the Propeller. The other thing is to not emulate but create some kind of Propeller native game development environment. This avoids the difficulty of emulation but now means someone needs to develop both the game toolkit and the games themselves. Emulation has the advantage of the original game library with dozens or hundreds of hit titles. But now you have to get people who are passionate enough to create games. Again, I'm not seeing it.

One immediate suggestion would be to try to eliminate the JSR OBJECTCOLL. Yes, it means you can use RTS to get back to the DOCLOOP, but it's costly in CPU cycles. You may have to use Branch+JMP sequences, but that's still faster than JSR+RTS. You can then also pull back the BEQ DOCNEXT into the OBJECTCOLL logic. How big are your objects & velocities? Is bounding box good enough or do you need pixel perfect? Can shots collide? You may want to have one set of routines for shots and another for other objects. Test the shots versus the other objects and the objects only against each other.

Let me correct that. There is no publicly available HLL for the 7800. Not to say that you have any obligation to make your toolchain available to others, but your personal toolchain doesn't help the OP achieve his programming dreams. Thus, if he wants to program the 7800 in anything other than ASM, he will need to develop the necessary tools.

In my personal experience, yes; for the following reasons: I don't believe there is a high level language for the 7800 like bB for the 2600. The TIA is fundamentally easier to understand that MARIA. (Playfield + sprite registers versus display list.) It takes more code on the 7800 than the 2600 to get something other than a black screen. Stella has a built-in debugger, I don't believe any of the 7800 emulators have any significant debugging capabilities. More 2600 sample code available.

Can you use both nibbles of the byte to double your sample rate? You'd need to come up with a EOL byte ($00 is my favorite since it sets the Z flag) then tweak the output so it doesn't appear in the normal data. It also might be possible to put in some kind of simple compression. You'd have to look at the data from the samples and see if there's any patterns. If the MSB of the byte is 1 (i.e. N set) then the byte is some kind of codeword. It could be a simple run-length encoding (bits 6-4 the count-1 and bits 0-3 the value). Oh, one other suggestion - add a high pass filter to your script, i.e. 20Hz - ?KHz. If nothing else it will pull out any DC offset.

When you say "zero experience in programming", do you mean: You have no programming experience whatsoever. If so, there are far, far better places to start than the 7800. (Maybe batari Basic if you want to work on a console rather than a PC.) You have programming experience, but only with high level languages. Again, you might want to start somewhere else. IMHO the 7800 is tough to use because you have to write a lot of code to get things happening on screen. You've programmed in assembly, but not in 6502. See #2, although if you have experience in more than one ISA then picking up the 6502 isn't too bad. (Until you discover the index registers are only 8 bit.) You have 6502 experience, but have never programmed any games. I'd advise reading through the documentation linked to in the first thread before setting your heart on making a game for the 7800. I know this may sound discouraging, but the only way a game gets done is if you want to do it and are willing to put in the time and effort and work through a lot of challenges. Finally, my thoughts on your game ideas: WWI dogfighter The 7800 GPU is sprite based with some tile abilities. There is no bitmap mode like the Apple ][ or C64. So anything on-screen has to be pre-rendered, not drawn with lines (ala vector graphics). Thus stuff which has to be at multiple angles is going to use up a lot of memory. Super Mario Bros port Ahh.. the desire of many a 7800 fan. Although it might be possible to create a SMB style game on the 7800 (and even possibly re-use some NES assets), there's just too many differences between the systems to make a port feasible. See my comparison of the 7800 and the NES.

How often will you be updating AUDV ? NTSC 2600 line rate is 15.7kHz, so you would low pass filter below 7.8kHz and use a 15.7kHz sample rate. Just for reference, telephones use 8kHz sampling.

Shortcuts - I think there were only a few (through the waterfall on the island was one) but they tended to be risky. Much easier to simply stay on the track; although if you had a boost or a star you could cut the corners in a few places. What did work really well in SMK64 was the slide/boost. It wasn't difficult to pull off (after some practice) and it added an extra bit of control & speed. SMK64 also got the start boost right. Again, with some practice the timing wasn't tough to get right most of the time.

It's too bad that you didn't have a better projection system for the Open Show. Hopefully the cost to rent a decent projection system will come down or you can get someone to sponsor it. I wonder if feeding the projector via it's VGA input (assuming it had one) would have worked better. Do all of the scaling & frame rate conversion on the Mac side. I'm trying to think if there's a way to help the students set their volume levels correctly. Something like a set of samples for various levels which they can use to tweak their films. i.e. normal dialog, max volume, recommended minimum. And maybe some way to semi-automatically tweak the volume of the film so it meets that profile.

In my blog archive you can find a fairly detailed description of the TIA audio generator which you can use to create precise waveforms. IIRC I kind used the waveforms like a frequency transform: For each waveform & it's 90 degree phase-shifted version Multiply the waveform against the block of samples (where bit=0 is *-1) Calculate the RMS of the in phase & in quadrature Compare the RMS for each waveform and select the two largest and calculate volumes Repeat for next block of samples In my case each block of samples was one TV frame long.

I did something like this 5 years ago (gawds): http://www.atariage.com/forums/blog/7/entry-1897-are-you-ready-for-this-pt-2/

The real question is whether they stock softcore. Blockbuster and the other chains don't and neither do the hardcore places. Can't get it on cable either. That's what I missed when the non-chain store closed years ago.

There's a fine line game creators must walk. Make a game more difficult and new players complain it's too hard, but if the difficulty doesn't increase then experienced players complain it's too easy. Practice does help, but sometimes you need to change tactics. I remember trying multiple times to beat WizPig in Diddy Kong Racing 64. But then I changed from using Diddy to the Mouse and focusing on keeping ahead of WizPig and I won the race after only a few tries. That being said, there are a few levels in Mario Galaxy 1 & 2 which I have no desire to try again.

I agree. In fact, I disagree with any online based feature - it's just too easy for it to disappear. And it's funny going back and watching some of the earlier DVDs how much time & effort was spent on the menus and transistions. Not so much these days.