Screen High (How much is it?)

[José Pereira]

From something I was looking yesterday from C64:

This C64 Creatures2 picture on MobyGames it's 282pixels high.

I've get it into Emulator and one only display the C64 normal 200pixels high:

Other one displays all, O.K.

Then I cut parts where are the C64 sprites on Borders:

 

C64:

-> 35pixels high sprite on Top

-> 200pixels Normal C64 screen Area

-> 21pixels high sprite in the bottom

---TOTAL: 256pixels high

 

 

Now about A8:

We control 240pixels high in PFs. talking.

But on real T.V. the PMs. go only on this 240high or go some more pixels Top and some more Bottom.

I think I read somehere, sometime ago that we have 256 scanlines for PMs.

This would be the same as C64 and that 'All Things screen high'=256scanlines

 

Seeing and remember things more clearly, you'll have to reserve in memory:

-> 256bytes for each Player.

Like this, if each A8 Player it's 8pixels=1byte, reserve in Memory 256bytes would be 256scanlines hight, right?

 

 

And more, if our PFs. screen it's 240, the PMs. would be what?

->8scanlines PMs. use only on Top

->240scanlines (PFs.&PMs.)

->8scanlines PMs. use only on Bottom

 

 

Help, please!...

Thanks.

Greetings.

José Pereira.

[Heaven/TQA]

PMs are 256 scanlines high, 8 pixels at the top and 8 at the bottom might be in the overscan area.

[José Pereira]

PMs are 256 scanlines high, 8 pixels at the top and 8 at the bottom might be in the overscan area.

 

That is saying what?

That I define each scanlines I need to use as PFs?

Like in others words, in a normal A8 screen 192pixels high I don't have PMs. on the Top and the Bottom Blank scanlines?

 

Or in other words:

I never see PMs. in the Blank (unused) scanlines?

 

 

 

 

Thanks.

José Pereira.

[pps]

PMs are 256 scanlines high, 8 pixels at the top and 8 at the bottom might be in the overscan area.

 

That is saying what?

That I define each scanlines I need to use as PFs?

Like in others words, in a normal A8 screen 192pixels high I don't have PMs. on the Top and the Bottom Blank scanlines?

 

Or in other words:

I never see PMs. in the Blank (unused) scanlines?

 

 

 

 

Thanks.

José Pereira.

Nope, you´re always able to get the PM all over the screen, no matter about the black (spare) lines, but you will not to be able to see all those available 256 "positions" of the PM, cause some (about the upper and lower 8 ones) are out of your display range.

 

Try to have a look of some of the full screen pictures within g2f and on the real machine (e.g. the bos 2002 picture, I did with an ancient version of g2f - found in tezz dir, if I´m right), you always have some things "left" on your tv set on ATARI.

[Tezz]

Try to have a look of some of the full screen pictures within g2f and on the real machine (e.g. the bos 2002 picture, I did with an ancient version of g2f - found in tezz dir, if I´m right)

yes it is, everytime I see it I think I'll mention it to Tebe to put it in the correct folder but then never remember

[emkay]

I wonder about this one:

 

 

 

336(168) * 288 Pixel...

 

[+wood_jl]

I wonder about this one:

 

 

 

336(168) * 288 Pixel...

 

 

Nice. Is that for real? At first I thought it was going to be an animated GIF. Then I was prepared to ask "are those real?" LOL.

[+Stephen]

I wonder about this one:

 

 

 

336(168) * 288 Pixel...

 

 

Nice. Is that for real? At first I thought it was going to be an animated GIF. Then I was prepared to ask "are those real?" LOL.

Yes - it's a great picture. Nice use of color on the left, and cute girl on the right

[José Pereira]

PMs are 256 scanlines high, 8 pixels at the top and 8 at the bottom might be in the overscan area.

 

That is saying what?

That I define each scanlines I need to use as PFs?

Like in others words, in a normal A8 screen 192pixels high I don't have PMs. on the Top and the Bottom Blank scanlines?

 

Or in other words:

I never see PMs. in the Blank (unused) scanlines?

 

 

 

 

Thanks.

José Pereira.

Nope, you´re always able to get the PM all over the screen, no matter about the black (spare) lines, but you will not to be able to see all those available 256 "positions" of the PM, cause some (about the upper and lower 8 ones) are out of your display range.

 

Try to have a look of some of the full screen pictures within g2f and on the real machine (e.g. the bos 2002 picture, I did with an ancient version of g2f - found in tezz dir, if I´m right), you always have some things "left" on your tv set on ATARI.

 

 

Hi.

 

I don't have a real Machine working and cannot test, but probably one woulkd come on this year...

And if soo I would like to know some things:

1.)- I have old T.V. that it's PAL and like that I would get 312scanlines high, right?

(NTSC it's also more than 256scanlines...)

And, for example this C64 Creatures2 from Nineties was supposed to work in real machines and probably in Europe and PAL, this way it will show all in the 312scanlines...

If Atari have 240 shown by PFs. it have more 72 outside... this 72 are 36Top and 36Bottom?

 

2.)- If I have a PM all high 256 placed on screen and a real Machine on my PAL old T.V. I see or not the 8Top+8bottom PM's pixels outside the 240screen scanlines?

 

3.)- That even more than 256 with the woman would it be shown with a real Machine and the old 312scanlines PAL T.V.?

 

4.)-As I said I don't have a real Machine to test, but another question is if I switch a real A8 into a Plasma/LCD large 720/1080/1280 scanlines high how is placed on screen the Image:

-> centered left&right / top&bottom?

-> 'Zoomed'?

-> 240scanlines normal screen but because these modern T.Vs. are large high scanlines how 'maximum' top and bottom outsides scanlines mores could be used with that 'just Pms.'?

 

 

 

 

 

Thanks.

Greets.

José Pereira.

[pps]

Try to have a look of some of the full screen pictures within g2f and on the real machine (e.g. the bos 2002 picture, I did with an ancient version of g2f - found in tezz dir, if I´m right)

yes it is, everytime I see it I think I'll mention it to Tebe to put it in the correct folder but then never remember

Oh, no problem for me. You did the corrections, so that the picture runs even on real machine.

 

Don´t remember correct know, but eighter g2f didn´t had that check error function it has now, or I missed that when I created that picture. g2f was still unknown in other world, than Poland these days

 

I had watched that project a while - even the first versions, where you was able to use it "only" for converting graphics to fonts, I had used. And they´re still on an old backup partition laying around

[ijor]

2.)- If I have a PM all high 256 placed on screen and a real Machine on my PAL old T.V. I see or not the 8Top+8bottom PM's pixels outside the 240screen scanlines?...

 

Jose,

 

The height of PM is bounded by the vertical blank. PMs exist only outside blanks (both vertical and horizontal blank). Vertical blank ends at scan line 7, and starts at scan line 248. These leaves you 240 scan lines, between 8 and 247 inclusive, for PMs. This applies both for NTSC and PAL computers. Note also that this is regardless of what you might actually see, which would depend on the specific TV, monitor, or capture hardware. This is what GTIA produces, emits and checks for collision. The actual visible height might be, of course, less.

[ANTIQ]

I expect the above picture delays the vertical blank by 48 lines to show the whole 288 line PAL field.

 

4.)-As I said I don't have a real Machine to test, but another question is if I switch a real A8 into a Plasma/LCD large 720/1080/1280 scanlines high how is placed on screen the Image:

-> centered left&right / top&bottom?

-> 'Zoomed'?

-> 240scanlines normal screen but because these modern T.Vs. are large high scanlines how 'maximum' top and bottom outsides scanlines mores could be used with that 'just Pms.'?

 

It should just scale the picture like when you watch standard definition ( 288p / 576i ) PAL TV.

[Rybags]

You can only get 240 scanlines of Playfield graphics on the Atari - there's no known way to get more.

 

C64 is 200, but if the sprites in border trick is used, you can have a single character that is repeatedly displayed in the 40 column area for the remainder of screen. Varying the content is done by changing the character definition or charset pointer in VIC, or the banking register in CIA which controls VICs RAM paging.

 

PMGs - Antic only does DMA for the 240 scanlines as mentioned before. The bytes before/after aren't fetched.

 

But, using the "scanline 240 bug" on Atari means you can have PMGs displayed on every single scanline, even the VSync ones. But the programmer has to load all the GRAFn registers.