hblank effects/effects in general

[Deleted]

So lots of games use various effects, such as warping of a background layer, or stretching (Thunder Force), or creating wavy backgrounds (Thunder Force 4, I believe, the fire level).

My question is, how do people come up with these effects, and how does one learn how to do them without being annoying? Does anyone have any simple ones to learn off of, up to complex ones?

I have plenty of neat ideas, but without knowing how to do these effects, it's kind of tough.

So, where do I begin? I know how to get more than 4 palettes on screen using the hblank, but aside from that, that's really it. I know moon had given me a few demos/examples, but I still want to actually know what I'm doing

[Deleted]

Does the H_V_INTS.BEX from the basiegaxorz137.exe do anything you want to learn?

[Deleted]

Did that BEX example do anything for ya? So far I could only dredge up another related thread here:
gendev.spritesmind.net/forum/viewtopic.php?t=1210

Sounds like touchy, time critical stuff.

[Deleted]

Not really, like, graphic tricks that you see in other games and such, and how to do them.

[Deleted]

Yeah, I just noticed you weren't really in it for the extra palette effects. More towards the squiggly, wavey effects.

moons Scroll.BEX seems to move things tile row by tile row. H_V_INTS.BEX just messes with colors during hblank. What we need is an explanation on how to move tiles by scanline during hblank.

[majoraj]

i know this is off topic but with regrards to sega16's retro toolkit, what if you could load the pallet directly from a CRAM file as i tend to struggle loading the pallet since the allocated size is in excess of what it should be, thanks for hearing me out

[Deleted]

Way, waaay off topic. I'd like to here what you have to say about the current topic though. Any experience with playing around with hblank?

Wecome to the forums!

A forums search turned up this raster example from Devster:
It seems to do stuff differently from the vblank/hblank system. I do notice some "raster" like effects when I insert scrolling commands. It might be worth playing around with this code to see what it can do.
for a=0 to 25
locate a, 0: print chr$(&h41+a);
locate a, 36: print chr$(&h41+a);
next
locate 5, 5: print "Rasters"
locate 6, 7: print "Test"
locate 7, 9: print "In"
locate 8, 11: print "Just"
locate 9, 13: print "Like"
locate 10, 15: print "On"
locate 11, 17: print "The"
locate 12, 19: print "Atari 2600!"
raster=0
valt
' waitraster 6
while 1
dalt
if raster=8 then
raster=0
reload
endif
halt
pallette readint(), 0, 1
raster++
wend

dataint &h00EE
dataint &h0E00
dataint &h0E0E
dataint &h0EE0
dataint &h0EEE
dataint &h0000
dataint &h000E
dataint &h00E0

[majoraj]

Hi,thanks for the warm welcome ;D , interesting stuff btw. ill give it a try, also i found this rom file by someone called Flavio its to do with the raster effects seemingly whether it is of any practical use i do not know heres the file anyway

Attachments:

[cabbage]

BEX has interrupts support, as described in the documentation. I haven't used BEX in a long time but it should be as simple as hooking hblank interrupt into whatever function you want to execute during hblank.

There is such a short time in the hblank, you can't execute much code there... but still some cool effects should be possible using only BEX code

edit: sorry for double post, I couldn't add attachment to this one by editing

[cabbage]

I wrote a small example demo which simply scrolls the background a little more each horizontal blank... The effect is very simple and boring, but you can see how to set up the interrupt.

Attachments:

[Deleted]

cabbage - I know your example is just to show how to use horizontal interrupts .. but for anyone who doesn't know this, you could ( and should ) do those kind of effects without using the hblank

Attachments:

[Deleted]

These are the things I'm looking to learn how to do

Is there any tutorials (or do either of you feel like writing some) on different methods of using scroll2, either by using precomputed sines/cosines/etc, as well a hblank methods?

[cabbage]

moon - that is a very elegant little program, I'm glad you shared it with us

[Deleted]

Sept 29, 2012 8:26:05 GMT -5 @elusive said:

Is there any tutorials (or do either of you feel like writing some) on different methods of using scroll2, either by using precomputed sines/cosines/etc, as well a hblank methods?

The only one I know is Lou's Pseudo 3d Page, but it only covers "abusing" scroll ( corners ) and hblank ( slopes ) for pseudo 3d racers. I should chip in

Sept 29, 2012 3:19:23 GMT -5 cabbage said:

I wrote a small example demo which simply scrolls the background a little more each horizontal blank

By the way, your example only uses every-other horizontal blank ( instead of every ).

I'm not exactly sure what the intended way of using "hblank 0" is in BEX ( timing-wise ). Oompa?

[Deleted]

You need to make your hblank and vblank code really small for vblank to have enough time to run. If you put in your vblank routine "hblank 0", you get a fraction of a delay. I was talking with markeyjester yesterday and even with a few short lines in bex, it's so unoptimized that it won't function properly. He had me do an asm code block and it worked perfectly fine. So now I'm working on learning some m68k asm for this sort of thing, but would still need to know how things work and various ways to use them.