Misc Blitz Demos

[Havie]

Originally Posted by earok

Or, if you really want to target OCS, I'd recommend using a horizontal scrolling routine with the pipes blitted to the background

You must have read my mind:

Or
I go the whole hog and rethink (using Daedalus' suggestion from earlier int he thread). Stop with the sprites and go for a hardware scroll and a tile map. I could then go dual playfield and have 8 colours for the background, 8 colours for the pipes (+4) and 16 colours for the bird. I could animate pipes using sprites (up to 4 pipes - 2 sprites per pipe). This would also give me the added ability to increase pipe density without any overheads and even have slanted pipes etc. I could also scroll the background using a hardware scroll too to add proper parallax.

[Havie]

Yes - people seem to moan about AGA but it would solve all my problems easily!

The routine doesn't allow reuse of sprites on the same scanline, though that's certainly possible on Amiga hardware (see Codetapper's article on Jim Power), but that'd be hard to pull off. To reuse a sprite on the same scanline, you'd need to program the copper to wait until after the sprite was drawn the first time, and then reposition the sprite to the new area (and repeat this for every single scanline with the sprite)

Just to be clear - does this mean only 1 sprite per scan line only or just no reused sprites?

Even if only 1 sprite per scan line is the only option, you code may be just what I need to finish my Doodle Jump game as currently it use vsprites code and this doesn't seem to work on 68000.

[Havie]

Originally Posted by earok

You need to do this if you haven't already (BB2OBJTYPES.RES will need to be present in your source folder)



I'm not so sure that a multiplexing routine would be a good fit for a flappy bird clone? Just hypothetically, you could do:

- Flappy Bird as a single 16px wide, 16 color sprite. Channels 1-2
- For an entire pipe section, including top, middle gap and bottom, do this as a single really tall, 16px wide 4 color sprite. That should allow you to get six pipes on screen at once.

Sorry - being a bit thick. I have a folder with the multiplexer BB file and the car iff. Does it go in here as this is where it is but it isn't showing in the Resident box?

Never used Residents before and have no idea what they are or do?

[Daedalus]

Residents are just precompiled chunks of code, like includes but the compiler doesn't have to build them each time. They're usually stored in the Blitzlibs: assign, wherever you have that. You need to add them yourself - the list doesn't automatically populate. You have to add whatever you need for the project (and often you need the full path, e.g. Blitzlibs:amigalibs.res).

In this case, the bb2objtypes.res simply contains newtype definitions for most of the Amiga objects, which lets you see inside them by assigning an appropriately-typed variable to the address of the object.

[Havie]

I copied Earok's .res file to libs and typed it into the box. The program runs but hangs with a blue screen. Any idea what I am doing wrong?

[earok]

@Havie sorry mate! I don't have any idea :/ in any case, you're no longer attempting a multiplexed sprite approach?


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A new demo has been added to my demos pack - this is a direct adaptation of Mike @ BitBeamCannon's AMOS demo with translucent glass effects.

There are a couple of slight nags - one is that I haven't updated the IFF image (and thus, the background still has AMOS commands), and the other is I had to implement a couple of rough workarounds to deal with differences between AMOS and Blitz.

[Havie]

Originally Posted by earok

@Havie sorry mate! I don't have any idea :/ in any case, you're no longer attempting a multiplexed sprite approach?

That's right - Flappy no longer need multiplexing but another old project - Doodle Jump does! Again, I could rethink how I have programmed Doodle Jump and instead of using sprites to give the impression of scrolling I could use actual hardware scrolling...that's for another day. Flappy to finish first...

[Havie]

Had another look at your multiplexer and lo and behold works today! Sometimes - having a break is helpful.

Have no idea what was different but it works! Thanks - might use in Doodle Jump after all!!!

[earok]

Open sourced an old procedural Map Generator that was originally designed to be used with AlarCity. It's in the repo with the rest of them - https://github.com/earok/BlitzBasicDemos/