multiple background scrolling

[GiGaBiTe]

i have seen in some games (sonic 3 on ice cap zone) that have more than 1 scrolling layer (assuming that layer a is used for the level and layer b is used for the background) i have seen up to 7 or 8 scrolling layers (that all scrolled at different speeds). plus clouds that are in front of the map layer.

how the heck do you make multiple scrolling layers if the vdp was never designed to do it?

[FonzieV]

;D magic, isn't it?

In fact, there is still 2 planes (even if its possible to have 3 planes using a trick).
And all is displayed with raster effect.

-So the bg plane is scrolled line per line using raster.
-The FG plane is scrolled line per line (to make burning effects, water effect...)
-The FG plane have a palette raster effect (to make the water color).

And they sometimes add sprites (like some tropical things) on foreground to make a 3rd plane effect.

Well, in theory its not hard to do same (just look @ my summer demo) in pratic , it's hard cause you need to make very fast operations (pure asm required)....

[oompa loompa]

sprites can be used to create more layers, like fonzie said. what's nifty is that the vdp has a huge sprite buffer, in that you can have 40 different sprites on the same line, and none would get deleted =P, unlike the tms9918, which has like a max of 4 sprites per line x.x

[GiGaBiTe]

that would explain the bug in the background on hidden palace zone. if you go far enough to the left or right you can see the end of the sprite line on all 4 or 5 fake bg planes. and since they all move at different speeds relative to the character, it has a wierd effect to it.

and i thought the max sprites the vdp could render at any one time was 80, or is that just for player sprites and enemys and stuff?

[oompa loompa]

yea, its 80 max for a screen that's 40 cells wide. i think there is also a max on the number of pixels the vdp can draw on the same line for sprites too. also, increasing the size of the sprites to something like 32x32 can make the planes bigger. like, an area of 256x256 can be made with just sprites XD, not taking into account the max number of pixels per line

[FonzieV]

I think i'll make a demo that shows 3 real scrollings plane and tile/tile effect scrolling soon...

To show all the available things...

[GiGaBiTe]

darksideserver.cjb.net/pictures/TEST.swf

like that? lol

that took bout 30 mins to make in flash mx 6


also, can you get the vdp to draw the screen at a higher resolution than it currently draws at? (think its 320x224)

but make it draw at 512x384? if thats possible, i would think it would require alot more memory.

[FonzieV]

"like that? lol"
Héhé, here is only one scrolling plane (i can do that on genesis with only one plane ... I told you i'll make 3 planes with overlapping + plane window ... héhéhé.


"but make it draw at 512x384? if thats possible, i would think it would require alot more memory."
There is a interlaced mode that makes 320*448,256*448,320*480,256*480... But it can't be used to display complex things... Maybe a picture, certainely no text.

[RedAngel]

I don´t know if it´s possible in Genesis but I have seen Amstrad CPC demos that show two screens very fast and you get the ilusion of a picture with more colours and definition than the normal one. The main problem is that I suppose it requires more resources than raster effects (swap colours) so you will get a flickering image.
Nintendo claimed that SNES had a 512x448 resolution but I have read that it is useless for games because of the flickering, so 99% of the games are in 256x224 mode ;D.

[Tulio Adriano]

GiGaBiTe said:

darksideserver.cjb.net/pictures/TEST.swf

like that? lol

that took bout 30 mins to make in flash mx 6


also, can you get the vdp to draw the screen at a higher resolution than it currently draws at? (think its 320x224)

but make it draw at 512x384? if thats possible, i would think it would require alot more memory.

Aww... that hurts my eyes, hahah!

As Phonzie Woltonov ( ;D ) said, you can do that kind of scroll using only one plane (usualy plane B) and doing the scrolling cell scroll or line scroll.

The only difference for your demo to a real life is that the nearest layers (edge) should scroll faster than the distant layers (center).

Anyway you got the idea, now, try to make it on little genny!

Cya!

[GiGaBiTe]

cant make anything for genesis because devsters basic thing keeps giving me the "active x, cannot create componet" error. and it gives same error on all 3 of my servers.

as for the back layers moving faster than the foward layers, this can be done if your focusing on a close object, and there is a large object in the distance. turn and it will appear to move faster. look at some of the lord of the rings footage.

[FonzieV]

"cant make anything for genesis because devsters basic thing"
Just try SGCC You'll get this sort of results in 10 lines of C code...

[oompa loompa]

GiGaBiTe said:

cant make anything for genesis because devsters basic thing keeps giving me the "active x, cannot create componet" error. and it gives same error on all 3 of my servers.

try downloading tomman's basiegaxorz v0.19 installer. the link is somewhere here on these forums at devster.proboards22.com/index.cgi?board=basiegaxorz&action=display&thread=1100898320

[GiGaBiTe]

since its basic programming for the genesis, can DATA statements be used to draw tiles, then another command be used to "put" them in region of the screen?

im used to quickbasic commands, and when uing basic programs from other sources i get confused

[oompa loompa]

yes, data statements can be used to hold tile data, but you will need to use some kind of command to load that data from cartridge rom memory to video memory. to put those tiles on the screen, you need to use the drawtile command, or whatever

graphics is totally different from quickbasic. on the pc, you have a framebuffer, and on the genesis, you get to use tiles