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emkay

The NOT derail Thread

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15 minutes ago, Heaven/TQA said:

From coder point of view…. Half data in ANTIC D to move than in ANTIC E means 2x speed up… I guess that’s what he wants to say… a real simple assumption but you have a real world example…

 

have a look at Mercenary 48k and 64k version.

Mercenary isn't optimized for Antic D. 

If you want a "world example" of available CPU time, just check Space Harrier. 

Fast "blitting" of " a lot" 3D objects (no discussion of what 3D should be. The location of 2D elements is 3 dimensional in the gameplay), the controls are smooth , a lot of animated DLI FX, AND clear digital speech at the same time. 

 

 

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19 minutes ago, Mazzspeed said:

When it comes t the C64 things are more complex, in some ways better. Rather than have ANTIC steal precious cycles as it hogs the bus, the C64's bus is interleaved between the VIC-II and CPU - However the VIC-II can request more bus time if required using the AEC signal.

 

It's all compromises.

We know that COLOR RAM reads and Sprite usage steals cycles on the C64 as well. It's only the display RAM that is not interfering the CPU.

 

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28 minutes ago, Mazzspeed said:

When it comes t the C64 things are more complex, in some ways better. Rather than have ANTIC steal precious cycles as it hogs the bus, the C64's bus is interleaved between the VIC-II and CPU - However the VIC-II can request more bus time if required using the AEC signal.

 

It's all compromises.

wouldn't say better but a quick skim of some decent sites may help people follow along... color ram, sprite use this chip that... and at lower clock rates...

https://kristerw.blogspot.com/2018/12/commodore-64-programming.html

it's complicated to say the least... guess that's why people borrow each others stuff to get the job done...

Edited by _The Doctor__

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And, well again about Mercenary. As the game only is drawing grids, the additional CPU usage for filling the changes on the screen is rather low. 

But, let's fill vectors, and objects , then compare. 

As Heaven stated, the use of RAM is also halved. 

From a 3D aspect it is a fair thing to have 3D at 1x1 pixels, calculating the 3D for 1x1 pixel presentation. ANTIC allows to have that with overscan.

Fake 3D as used on the C64 , to present 160x200 (320x200) pixel on a 40x20  calculation. Might look better, is actually good for games, but a full fake on 3D calculations. 

 

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48 minutes ago, emkay said:

We know that COLOR RAM reads and Sprite usage steals cycles on the C64 as well. It's only the display RAM that is not interfering the CPU.

 

Actually, the VIC-II has direct access to color ram at $D800, as not to slow the CPU at all. It can actually fetch the next row of characters and access color ram at the same time.

 

This is beneficial regarding the vast majority of games available at the time (2D platformers and shmups), however it's a disadvantage when it comes to any form of buffering as color ram has to be fetched in real time. The whole clock rate thing really isn't as much of a limitation as people like to make out regarding the C64's architecture. These days with REU's being more popular acting as bllitters, it's even less of a problem.

Edited by Mazzspeed

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1 hour ago, Mazzspeed said:

Actually, the VIC-II has direct access to color ram at $D800 via pins A8 - A11, as not to slow the CPU at all. It can actually fetch the next row of characters and access color ram at the same time depending on graphics mode and the way screen memory is used.

 

This is beneficial regarding the vast majority of games available at the time (2D platformers and shmups), however it's a disadvantage when it comes to any form of buffering as color ram has to be fetched in real time. The whole clock rate thing really isn't as much of a limitation as people like to make out regarding the C64's architecture. These days with REU's being more popular acting as bllitters, it's even less of a problem.

 

Edited by Mazzspeed

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1 hour ago, Mazzspeed said:

Actually, the VIC-II has direct access to color ram at $D800, as not to slow the CPU at all. It can actually fetch the next row of characters and access color ram at the same time.

 

This is beneficial regarding the vast majority of games available at the time (2D platformers and shmups), however it's a disadvantage when it comes to any form of buffering as color ram has to be fetched in real time.

 

 

Yes. The time consuming part there is to assure the color ram to be fetched at the most perfect time. 

 

1 hour ago, Mazzspeed said:

 

 

The whole clock rate thing really isn't as much of a limitation as people like to make out regarding the C64's architecture. These days with REU's being more popular acting as bllitters, it's even less of a problem.

The flaw there is that it is really a DMA thing. Limited to the point that video can be streamed ,  but not the audio. 

The page flipping in the Atari is about "16" times faster, as a single command can switch a 16K (up to 32K)memory bank.  

Some external device added, allows to make interactive TV, if you understand :)

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Wow! I'm enlightened!

In ANTIC D a screen has only 3840 bytes. The quickest possible sequence to serve a byte for e.g. clearing the screen would be

LDA #0

STA SCREENMEMORY+0

STA SCREENMEMORY+1

STA SCREENMEMORY+2

...

That's 15360 cycles. Now if I would this do for every frame (in PAL) i would only spend 768000 cycles for clearing the screen in stunning 50 FPS!

It's so coool. I call this now 3.5 MHz mode too!

 

Wait. If I would go ANTIC 4 the screen has only 960 bytes to be served. Clearing with an empty character would only take 3840 or in 50 FPS

192000 cycles! That's even better, I just discovered the 14 MHz A8 mode!

😁

 

Many games should go for that mode or even the ANTIC 5 28 MHz mode!

One moment - isn't that what most games do? Sticking to character mode to have less screen memory to be served? I'm confused...

🤔

 

(Yes, I dropped the DMA penalty intentionally. Who cares, if someone else doesn't care that filling screen memory only wouldn't make a meaningful title.

Remember the Stunt Car Racer discussion? Where setting up the screen memory is the minor part and all the more costly calculations have to be done graphic mode independently... and on the other side setting the colors in character blocks actually brings an advantage...)

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1 hour ago, emkay said:

Yes. The time consuming part there is to assure the color ram to be fetched at the most perfect time.

Well that's controlled by the VIC-II itself as it has it's own bus directly to color memory, I don't really see how it's time consuming.

 

1 hour ago, emkay said:

The flaw there is that it is really a DMA thing. Limited to the point that video can be streamed ,  but not the audio. 

The page flipping in the Atari is about "16" times faster, as a single command can switch a 16K (up to 32K)memory bank.  

Some external device added, allows to make interactive TV, if you understand :)

It's not really a flaw. Looking at the schematics and the way I understand it, you can halt the processor using AEC, from there you are free to put any address you want on the address bus and the PLA will sort it out regarding corresponding registers. Keeping in mind all the conditions that need to be met regarding the VIC-II, different addresses can be read from and written to at 1Mhz, which is actually faster than when controlled via the 6510 - It's around 1 million bytes /sec. So SID and VIC-II can in theory be updated faster and in sync directly from the REU with dedicated DMA controller and corresponding DMA pin on the cartridge port. The Commodore REU is actually very flexible, more flexible and faster than many believe and the way the DMA line on the cartridge port and the AEC line between the VIC-II and 6510 work is more complicated than simply stating bank switching is better. However, using Ultimax mode, bank switching via the cartridge port is also possible on the C64 (obviously not to color memory). The REU also supports the swap command, effectively similar to bank switching.

 

I've already highlighted the speed possible via the cartridge port using DMA in relation to storage data transfer speeds, it's faster than the A8 can achieve (EDIT: SIDE3 may change that, in fact I believe it does - Speeds may be similar theoretically) and not limited by processor speed. Please bear in mind that in making such a statement I am in no way saying the C64 is better than the A8 or vice versa, it's all compromises. I'm not looking for an us vs them argument. If people want an argument I'm just gonna nope out of the thread and you can believe whatever you want to believe.

 

The C64 DTV actually had an integrated DMA controller.

 

 

Edited by Mazzspeed

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1 hour ago, Irgendwer said:

Wow! I'm enlightened!

 

No, You are surely not enlightened.

 

1 hour ago, Irgendwer said:

 

(Yes, I dropped the DMA penalty intentionally. Who cares, if someone else doesn't care that filling screen memory only wouldn't make a meaningful title.

Remember the Stunt Car Racer discussion? Where setting up the screen memory is the minor part and all the more costly calculations have to be done graphic mode independently... and on the other side setting the colors in character blocks actually brings an advantage...)

 

I'm not the one who forgets the relevant stuff. 

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1 hour ago, Mazzspeed said:

. I'm not looking for an us vs them argument. If people want an argument I'm just gonna nope out of the thread and you can believe whatever you want to believe.

 

 

Good point. 

The thread is still not about  C & A ;)  . It's about the main point that still stuff is missing on the Atari. And particular here in the forums are several people" know it all" . Hacking towards people who really know things. 

In the past there had been interests in doing some 3D stuff, guess wo defended there Atari against it? 

Some people  here really should learn , not to put their own thoughts into other's mouth.  

 

I also recognized your first encounter with me was heavily preloaded by some special people. 

 

Really. Decades have past, just because they interefere every thread with their "opinion" and get personal as well. 

To know that some people do care and learn while we do communication, is at least a little relief.

 

 

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11 minutes ago, emkay said:

And particular here in the forums are several people" know it all" . Hacking towards people who really know things. 

 

That sounds very familiar to me!

 

(I really feel sorry for the members who blocked you. This is so funny!)

 

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5 minutes ago, Irgendwer said:

 

That sounds very familiar to me!

 

(I really feel sorry for the members who blocked you. This is so funny!)

 

And again someone puts his thoughts into other's mouth.

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I'm still impressed with that "Wilmunder's Star Raiders II" .

The fast and realistic 3D is stunning for such an old computer. 

 

A game like Elite would have made much more sense than with the fake 3D space view. 

 

One could only imagine a game like Elite, with fast and realistic 3D, the GTIA graphics for image details, some Hires colored trading screen...

Solid ships instead of empty vectors or circles. And so on.  

 

 

 

 

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12 minutes ago, youxia said:

I don't see any "solid 3D" in there.

Check the difference between the C64 version and the Amiga version (for example). 

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Would be nice to edit the first post for adding the number of derail posts.

Just for the statistics.

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do you need edit first post privs? just ask the admins... ;)

You can use the @ feature with any admins name to get their attention, or report on your post and ask for the privs with the reasons why..

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33 minutes ago, emkay said:

Check the difference between the C64 version and the Amiga version (for example). 

Sorry, I don't undersdtand. Difference of what version? I was referring to the video you posted and the "Solid ships instead of empty vectors or circles"

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40 minutes ago, youxia said:

Sorry, I don't undersdtand. Difference of what version? I was referring to the video you posted and the "Solid ships instead of empty vectors or circles"

The Atari could do solid ships, instead of just flickering empty circles or grid based objects. In Elite less objects were used than in this Starraiders II.

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40 minutes ago, emkay said:

The Atari could do solid ships, instead of just flickering empty circles or grid based objects. In Elite less objects were used than in this Starraiders II.

a) Elite is a different game than Star Raiders. It could be its resources were spent elsewhere.

b) I still can't see any solid ships in this video so it's irrelevant either way

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Heaven did a "voxel sphere" part in Arsantica 3. 

 

The game wouldn't need that complex presentation of a 3D object. 

 

 

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45 minutes ago, youxia said:

a) Elite is a different game than Star Raiders. It could be its resources were spent elsewhere.

b) I still can't see any solid ships in this video so it's irrelevant either way

Where exactly is Elite different to Star Raiders? 

It's mainly the presentation. Things were happening in the background as well. 

Have you realized the whole Starraiders (1) game is less than 10K . So it's all about calculations.

And now try to imagine how such a game could be on a Megacart. 

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3 minutes ago, emkay said:

Where exactly is Elite different to Star Raiders? 

If you need to ask, then I can't really help you. Elite Frontier has properly filled objects and it's a slideshow. On Amiga. And coding some voxel objects in a demo is a far cry from producing an entire game using this tech.

 

Anyway, this is going nowhere, like in 99% of these kinda threads - which are mostly a weird mix of wishful thinking and goalpost shifting - so I'll leave you to it.

 

 

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