If we take this from C64 how to get C64 ColourMap

[José Pereira]

The problem is there's a huge gulf between a screen and an engine. Until someone finds a way to make the coloring work and combines it with a fast enough code that can handle all scenarios needed by the game at a good frame rate, it's just not that exciting.

 

Exciting?

 

But aren't this to talk about ways to do Things.

Are you and all waiting for Miracles or all waiting for someone 'TURN ON the light' to all the others.

 

It seems that all are waiting for all the others

[José Pereira]

Until someone finds a way to make the coloring work and combines it with a fast enough code that can handle all scenarios needed by the game at a good frame rate

 

Is to get some coders answers/ways to achieve this that the Topic (and other ones...) was created.

 

 

We are all here, first, to talk.

If then something or someone gets or code something it's another thing (that, of course, would be great )

[Creature XL]

Emkays idea, to use a kernel, sounds good, as the one-colored toad is a good object to hide the color changes for the right side. Hard in char mode, but easy in bitmap mode I guess.

[Creature XL]

Emkays idea, to use a kernel, sounds good, as the one-colored toad is a good object to hide the color changes for the right side. Hard in char mode, but easy in bitmap mode I guess.

[analmux]

As emkay already wrote: you can use the VSCROLL-trick to avoid the badlines in font-modes. A DLI can help. Of course there's also a restriction then, as new display data won't be fetched either (only new font-data). Thus at the same time the DLI is needed for font-changes. And another restriction is the placing of the COLPF2/3 selection: now you're restricted to vertical bars.

[oky2000]

Start with something that is on A8 like Elektraglide and put cars on it, that way you are building on what someone else did with unique features of A8 chipset

 

Or even try doing the forest level of Shadow of the Beast from the Amiga.

 

Both those games are designed around raster colour changes to improve the onscreen colours massively with the use of a large palette to play with, play to the strengths of the machine as others have said

 

 

This is just to 'expand knowledge' and see what could be done: Tricks, learn about 'colour changing',...

We can have better than C64 in ProjectM, SpaceHarrier 3D GR.7 or GTIA and C64 would have better for Armalyte/sprites/2D with lots of sprites/1:1 and 2:1 Mixing,...

But if we on the past have a large A8 Market and Out Run, Power Drift or others had A8 versions and A8 coders improve their knowledges like the C64 ones, how they would done these type of games on A8, just this!

What would had been possible (it doesn't necessarily be understanded as a try to port or anyone code this type of games today)

Just some free talking here to all... coders can say their opinions, I am not force them to code anything.

(Was thinking and see some Elektraglide last night and have some questions... but would put them later, as they aren't exactly what I am trying to find here...)

 

That's fair enough I am just saying that if you took Elektraglide engine and improved it graphically (example more DLIs for ground and sky graduation to make most of the palette) and replaced the poly objects with some car sprites you would make probably the best looking 8bit into the screen racing game too

 

I think it's fair to say only one other programmer did decent 3D into the screen psuedo sprite scaling game and that was for Buggy Boy, the rest are all programmed by a genius coder called Chris Butler, had he not been the programmer then some of these games would have been much worse. Obviously some people think they are rubbish anyway haha

[Heaven/TQA]

Chris Butler is not a bad coder...

 

http://www.mayhem64.co.uk/butler.htm

[José Pereira]

That's fair enough I am just saying that if you took Elektraglide engine and improved it graphically (example more DLIs for ground and sky graduation to make most of the palette) and replaced the poly objects with some car sprites you would make probably the best looking 8bit onto the screen racing game too

 

 

But isn't Elektaglide a little bit like DimensionX?

With soo much attention to the A8 strenghts and it ended up with a game that you can't get much more in it?

 

I read the Adam Bylliard interview and from what I understand it's all done in Bitmap Mode 4colours (no PF3 5th colour) and all the Road turns are done by the A8 can scroll horizontally left and right each scanline.

Then, there's even the End Tunnels tricks of the Players placed on sides to get the Black colour... this is saying that you can only use 4PMs to get the objects, cars or whatever you think of, but they are soo difficult and not many as we would really need.

You can, for example, put a car, but you can't get a car and a side Gfxs. and so on...

Or you can?

 

 

Elektraglide uses Bitmap Mode, is there any way of get more colours than the four ormal?

-> Re-use PMs. but that would mess in the Horizontal scroll, right?

-> Same as Mid-scanline changes?

 

I think that it would be even more difficult to get there more Gfxs. and cars than a 'simple?'

C64 car game that moves/uses ColourMap into an ANTIC4 PMs. overlays.

 

 

 

Keep coming your comments and ideas.

Greets.

José Pereira.

[Heaven/TQA]

isn't ElectraGlide using mode10?

[oky2000]

What I mean is the way it plays to the strengths of the A8. DLIs and massive colour palette = great potential for doing these C64 games in a different way that's all. Whether they use bitmap or char modes for the game engines what you could do is just think how to put DLIs here and there to improve the depth cueing and sky graduations too.

 

Playing to the strengths of the A8 as I see them, but then I am not a programmer I admit that

 

Maybe if you compare the C64 and A8 versions of Pitstop 2 it will help you too? I don't know, that's a nice game and there are differences in graphics.

[José Pereira]

isn't ElectraGlide using mode10?

 

No, GTIA9 it's on Gray Panel on the Bottom, each scanline is made of just four colours.

 

The trick there is that each scanline can scroll Horizontally on the two directions.

All the Objects like Trees, Balls,... are PMs.

 

Adam Interview at AtariMania:

"

 

"ElektraGlide," unusually, used a bitmapped display in 160x96 mode. One of the technical aims of writing the game was to have real large objects "moving" on the display, unlike the endless 2-D scrolling games that were around. I say "moving" since no way could the processor actually repaint large objects fast enough. It was all a lot of smoke-and-display-lists, so to speak.

 

I used display list interrupts every other scan-line so I could have fine grain control. The road you were on twisted and turned by horizontally scrolling each scan-line in the display list to give the effect of you coming up on curves. Display list interrupts allowed the rolling colors down the edges of the road. When a tunnel, which eventually filled the screen, came up, I just set up interrupts to change the color registers further and further up the display and also restore the colors further and further down the display with the effect that you got this big looming wall of a tunnel approaching. The tunnel entrance was superimposed afterward using a spare player! More frightening was the case where the road curved inside a tunnel. I needed to blank out the part of the road occluded by the supposed tunnel wall. This was done by placing a large player at the apex of the curve and switching the player priorities at that apex scan line. I did a similar gag for exiting the tunnel, but ran out of players. On overscanned TVs, the darkness of the tunnel runs out at either edge revealing the coming landscape."

 

 

 

By the way, get this Adam's code is it possible to put Gfxs. like Trees/Cars/... by SoftSprite and use PMs. overlays?

(if it is, I just found how to have something more on screen )

[Rybags]

Nope. Antic D (Gr. 7 )

 

With HScrol doing road shaping it means that any softsprite plotting needs to have offset calculations per scanline.

 

But Elektraglide AFAIK uses PMGs for all the other objects, trees too.

 

It's not "unusual" in using HScrol to do the road.

 

Pole Position does exactly the same and all objects are also PMGs. Plus it does so in Mode E.

 

Other games like Pitstop, Great American Road Race, AFAIK just build the entire screen without scroll tricks. But those games are a lot less convincing with their driving illusion.

Edited July 20, 2011 by Rybags

[José Pereira]

Nope. Antic D (Gr. 7 )

 

With HScrol doing road shaping it means that any softsprite plotting needs to have offset calculations per scanline.

 

 

The two use GR.7.

Like that a cross of the 'each scanline scroll' of Adam and the 'plot soft sprites' of Sheddy and PMs. overlays I could build something

 

(did they know Emkay when they start coding these Games )

Edited July 20, 2011 by José Pereira

[José Pereira]

 

PF0- Road colour

PF1- Road Margins (Light Gray/Blue)

PF2- Road center lines (Yellow)

Backgr.- Grass Green colours

 

 

This is using a Bitmap Mode and PF3 would only be used if 5th Player enabled.

If I have colour registers like this:

PF0- Road colour

PF2- Road Margins (instead of PF1)

Backgr.- Grass colours

 

I would have free PF1 to Mask P2&P3 PRIOR0 Oring for some Gfxs. on the Borders.

To get the center Road yellow Lines can I use the 4Missiles and that Yellow would be 5th Player PF3 colour?

Each scanline would be just one expanded Missile but 4scanlines would take the 4Missiles.

It would need to 'point'/Multiplex the same Missile each 4scanlines at a different xPos.

Is this tricky or it is coding possible and the game running?

[Rybags]

Changing 4 missile positions as well as HScrol would use just about all the availble cycles, you'd still want some free probably for Player changes and colours.

 

Remember you're dealing with wide DMA cycle losses.

 

The way around that would be to only change 2 missiles per scanline on a 0/2, 1/3 basis.

[José Pereira]

Changing 4 missile positions as well as HScrol would use just about all the availble cycles, you'd still want some free probably for Player changes and colours.

 

Remember you're dealing with wide DMA cycle losses.

 

The way around that would be to only change 2 missiles per scanline on a 0/2, 1/3 basis.

 

You only have 1Missile in each scanline.

1Missiles covers all that center Lines pixels.

4scanlines would be the 4Missiles.

 

You will only change 1Missile xPos. on each scanline.

[Rybags]

I don't see what you're getting at.

 

Why would you want to use all the missiles for one object when just one would do?

 

And since the centre line should always be away from the side of screen, it doesn't fall into the critical HBlank time, the change can occur in display time.

[José Pereira]

And another thing, on the Mountains and the road isn't GR.7 but Gr.15 1pixel Tall.

You just see that on my Picture... Mountains is simply to see but Road can be seen in the center yellow lines that there are some with just 1pixel tall.

[José Pereira]

I don't see what you're getting at.

 

Why would you want to use all the missiles for one object when just one would do?

 

And since the centre line should always be away from the side of screen, it doesn't fall into the critical HBlank time, the change can occur in display time.

 

 

Just because I would need to have a PF free for the sides Gfxs.

If in Bitmap Modes I don't have PF3 and that Yellow Lines are or can be the width of a Missile I thought that using just one Missile and change it's xPos. on every single scanline it would be more tricky than waste the four Missiles in 4scanlines and then just change one xPos. at each scanline.

[Rybags]

The Elektraglide road is Mode D.

 

You're only getting an illusion that it's higher resolution because colour the centre lines are solid and the colour changes are on alternate scanlines to the HScrol changes.

Edited July 20, 2011 by Rybags

[emkay]

What I mean is the way it plays to the strengths of the A8. DLIs and massive colour palette = great potential for doing these C64 games in a different way that's all. Whether they use bitmap or char modes for the game engines what you could do is just think how to put DLIs here and there to improve the depth cueing and sky graduations too.

 

Playing to the strengths of the A8 as I see them, but then I am not a programmer I admit that

 

 

My words.

 

Instead of running behind "hires" and "Colour Cells" , The A8 can do wonderful ambient colour manipulations during gameplay, and offers enough details....

 

 

 

http://www.youtube.com/watch?v=LbAnsdWVV5k

 

Gr. 7 , Gr. 10, 4x4 Mode. GTIA overlay.....

 

 

 

Zoomed picture 256 colours no interlace (for example)

[oky2000]

I suppose this char based image from a BASIC game I was testing illustrates my point. Best not to try to copy something pixel for pixel palette for palette from C64 to A8 but to mentally dismantle the idea and understand what the C64 programmer was trying to achieve and then pick the best way of doing it on the A8 rather than looking to carbon copy the resultant code.

Edited July 20, 2011 by oky2000

[José Pereira]

What I mean is the way it plays to the strengths of the A8. DLIs and massive colour palette = great potential for doing these C64 games in a different way that's all. Whether they use bitmap or char modes for the game engines what you could do is just think how to put DLIs here and there to improve the depth cueing and sky graduations too.

 

Playing to the strengths of the A8 as I see them, but then I am not a programmer I admit that

 

 

My words.

 

Instead of running behind "hires" and "Colour Cells" , The A8 can do wonderful ambient colour manipulations during gameplay, and offers enough details....

 

 

 

http://www.youtube.com/watch?v=LbAnsdWVV5k

 

Gr. 7 , Gr. 10, 4x4 Mode. GTIA overlay.....

 

 

 

Zoomed picture 256 colours no interlace (for example)

 

 

Emkay how do you get the Browns Luminances?

GTIA 16shades Mode9 is all 15Luminances and Black as Backgr. by the 4bit Pair in the Backgr. Register.

This would only be Oring luminances by the Missiles as 5th Player and the conflict as GTIA Mode9 doesn't use Backgr. Register.

Then all the 4Players will be over Gfxs. Backgr. Register colour and no Oring possible.

 

How you get thhose Brown Luminances?

[emkay]

 

How you get thhose Brown Luminances?

 

 

Kernal is the key

[José Pereira]

 

How you get thhose Brown Luminances?

 

 

Kernal is the key

 

 

That's what I thought but:

-> You're doing just one change (something like one 'LDA' and one 'STA') on the Backgr. register because you're in GTIA Mode9 then changing Backgr. Luminance0 you just change all the other 15Luminances 4bit Pairs of that colour (like if you Kernal PF2 in Hi-Resol. Gr.0&8 )

If in a 2:1 ratio Bitmap Mode you have to change PF each time and then 4or5 kernals on the scanline (and can't change all 3PFs. at the same xPos., I think, right?).

And these 4or5changes would take you all the cycles, isn't it?

-> Is it possible, for example to do these Kernals (some changes of two PFs.) to get some Pictures like Exploding Fist, for example?

(the Players Fighters with one PF/Backgr. registers and the 4PMs would then be possible...)

I see you that you've done some Mid-scanlines changes at Defender of the Crown pictures and at ANTIC4 out of BadLines

Edited July 20, 2011 by José Pereira