how could some PCE games achieve parallax scrolling?

[sanjo]

I know one of the PCE's weakpoints was that 1 background layer that made it difficult to achieve parallax scrolling, but it seems some games were able to do it

like this part of dracula x
https://youtu.be/IV5TvOlKsj4?t=1h20m59s

or this stage of gates of thunder
https://youtu.be/oGguCcizT6M?t=28m24s

how could they do it, while say, ninja gaiden could only achieve a really choppy one?

[Arkhan]

Ninja gaiden has bad math and stupidity.

Parallax can be done with 1 BG layer.  what you're asking is how they faked layers.

You do it with sprites, or you use dynamic, animated background tiles to simulate depth.

[TheOldMan]

I know one of the PCE's weakpoints was that 1 background layer that made it difficult to achieve parallax scrolling but it seems some games were able to do it

The pce has a pair of registers in the vdc that allows it to offset from the start of a screen. Strip-style parallax (where you have several horizontal strips that move at different speeds) is extremely easy to do.

how could they do it, while say, ninja gaiden could only achieve a really choppy one?

Don't blame the machine. Blame the programmers.

[Necromancer]

It's all line scrolls, animated background tiles, sprites by themselves, occasionally the far background color (separate from the 'normal' background layer), or some combination thereof.

In your Dracula X example, most everything is standard strip style parallax with the only things overlapping anything being the columns, which are made of sprites.  Also, see Ninja Spirit for a good example of animated tiles; the drawback of this approach is that tiles have square edges, which Ninja Spirit hides by using dark backgrounds and black infill on the foreground tiles with rounded edges.

Games like Ninja Gaiden aren't examples of the machine's limitations.  They're just poorly executed and could undoubtedly be done better with more time, bigger roms, better talent (art and programming), etc.

[DragonmasterDan]

If you want to see the wrong way to do it look at Ninja Gaiden

[Keith Courage]

If you want to see the wrong way to do it look at Ninja Gaiden

This and ys 3

[Bonknuts]

I know one of the PCE's weakpoints was that 1 background layer that made it difficult to achieve parallax scrolling, but it seems some games were able to do it

like this part of dracula x
https://youtu.be/IV5TvOlKsj4?t=1h20m59s

or this stage of gates of thunder
https://youtu.be/oGguCcizT6M?t=28m24s

how could they do it, while say, ninja gaiden could only achieve a really choppy one?

 That's a link to Lords of Thunder, not Gate of Thunder.

 The PCE can do "parallax" style scrolling just like most 16bit systems; that is to say it divides sections of the background to scroll a different speeds. This can be done up to a single scanline to have the effect of "linescrolls".

 What you're referring to is overlapping parallax. And that's obviously something more complicated to do with only one background. Like others have mentioned, sprites are often used to small overlapping parts.

 Just look at the Dracula X example you listed. Everything is made up of a single background layer as different speeds. Only the pillars holding the bridge are overlapping, and they are sprites.

 But as you're probably aware, you can only have soo many sprites on a single display line before flicker or blankout happens. There's another technique called dynamic tiles. Lords of Thunder does indeed use them in some places, but definitely not as common as it uses sprites for overlapping parts.

 One great example of dynamic tiles in Lords of Thunder, is the sand level wit the giant sand dragon/thing. The sand part is dynamic tiles and allows the dragon's "body" to move back and forth, independent of the multi-scrolling layers of the sand. This is achieved because the sand is a single column of 8x8 blocks, repeated across the screen horizontally. Each 8x8 block in that column is pre-animated to a full left to right rotation.

 Dynamic tiles has a restriction on complexity; both size in storage AND the cpu resource to upload each update per frame. On top of that, sprites can be combined with them for an even more convincing effect (the sand Dragon in LoT does this; the head and tops of spikes are sprites).

 There is another techniques, but they are limited. But when combined in certain ways - allows more complex scrolling. Back ground color scrolling is one of them (the first stage of Magical Chase), or character scrolling (Ys 3). Character scrolling is definitely rough, but at high speeds it can be very convincing if done right.

 Ninja Gaiden on PCE tries to do character scrolling, but messes it up really bad. Normally, parallax designed around games designed from the ground up for the system - tends to look really good. Ninja Gaiden on the PCE kind of a budget title. Ignoring the parallax itself, the background tilework/art is actually inferior to the NES one which incorporates depth to the platforms with less tiles than the PCE (the PCE is fairly flat looking - lacking depth in the side view).   

[sanjo]

I know one of the PCE's weakpoints was that 1 background layer that made it difficult to achieve parallax scrolling, but it seems some games were able to do it

like this part of dracula x
https://youtu.be/IV5TvOlKsj4?t=1h20m59s

or this stage of gates of thunder
https://youtu.be/oGguCcizT6M?t=28m24s

how could they do it, while say, ninja gaiden could only achieve a really choppy one?

 That's a link to Lords of Thunder, not Gate of Thunder.

 The PCE can do "parallax" style scrolling just like most 16bit systems; that is to say it divides sections of the background to scroll a different speeds. This can be done up to a single scanline to have the effect of "linescrolls".

 What you're referring to is overlapping parallax. And that's obviously something more complicated to do with only one background. Like others have mentioned, sprites are often used to small overlapping parts.

 Just look at the Dracula X example you listed. Everything is made up of a single background layer as different speeds. Only the pillars holding the bridge are overlapping, and they are sprites.

 But as you're probably aware, you can only have soo many sprites on a single display line before flicker or blankout happens. There's another technique called dynamic tiles. Lords of Thunder does indeed use them in some places, but definitely not as common as it uses sprites for overlapping parts.

 One great example of dynamic tiles in Lords of Thunder, is the sand level wit the giant sand dragon/thing. The sand part is dynamic tiles and allows the dragon's "body" to move back and forth, independent of the multi-scrolling layers of the sand. This is achieved because the sand is a single column of 8x8 blocks, repeated across the screen horizontally. Each 8x8 block in that column is pre-animated to a full left to right rotation.

 Dynamic tiles has a restriction on complexity; both size in storage AND the cpu resource to upload each update per frame. On top of that, sprites can be combined with them for an even more convincing effect (the sand Dragon in LoT does this; the head and tops of spikes are sprites).

 There is another techniques, but they are limited. But when combined in certain ways - allows more complex scrolling. Back ground color scrolling is one of them (the first stage of Magical Chase), or character scrolling (Ys 3). Character scrolling is definitely rough, but at high speeds it can be very convincing if done right.

 Ninja Gaiden on PCE tries to do character scrolling, but messes it up really bad. Normally, parallax designed around games designed from the ground up for the system - tends to look really good. Ninja Gaiden on the PCE kind of a budget title. Ignoring the parallax itself, the background tilework/art is actually inferior to the NES one which incorporates depth to the platforms with less tiles than the PCE (the PCE is fairly flat looking - lacking depth in the side view).

Thanks a lot for the detailed explanations. it was exactly what I was looking for.
Shame about Ninja Gaiden though. I thought scrolling aside, it looked great. Much better than the SNES remake. Very bright colors, details, and use of shading. Stage 2-2 reminds me of one of the Final Fantasy 6 areas.

[Dicer]

I think someone was hacking the Ninja Gaiden rom to kill the scrolling, if I recall, wonder what happened to that?

[Gredler]

The dungeon explorer opening scene sells overlapping layer parallax very well, can we get a breakdown of how that was achieved? Is it strips of tiles with sprites where it overlaps?

[Black Tiger]

The dungeon explorer opening scene sells overlapping layer parallax very well, can we get a breakdown of how that was achieved? Is it strips of tiles with sprites where it overlaps?

Yep.

[technozombie]

The dungeon explorer opening scene sells overlapping layer parallax very well, can we get a breakdown of how that was achieved? Is it strips of tiles with sprites where it overlaps?

Yep.

BT with the perfect breakdown.

[Bonknuts]

I forgot about these:


 The sprites are the chroma ones (green or red). BG layer is black and white.

[sanjo]

I think someone was hacking the Ninja Gaiden rom to kill the scrolling, if I recall, wonder what happened to that?

I hope this is true, the backgrounds, details and color are so much better on the PCE than SNES remake

[Digi.k]

I know one of the PCE's weakpoints was that 1 background layer that made it difficult to achieve parallax scrolling, but it seems some games were able to do it

Just to randomly add to this thread.