Flip screens on CPC / Emulator

Leonie · 20:11, 18 June 10

@ Markus:

That´s a bit thick...X-Rated...superb picture!

Forget C64, forget Amiga.......CPC+flip (+Markus?) is the measure of all things!
I wish there would be no flicker...

Devilmarkus · 20:22, 18 June 10

Quote from: Leonie on 20:11, 18 June 10
@ Markus:

That´s a bit thick...X-Rated...superb picture!

Forget C64, forget Amiga.......CPC+flip (+Markus?) is the measure of all things!
I wish there would be no flicker...

LOL...
thanks.
Yes the screens are nice with non-flickering display.

Here's another: (Same 4 base colours, result has 10 measured colours)

Converting to mode 1, 4 colours with 50% luminance and Floyd Steinberg dithering:

Converting to same palette with 150% luminance and Floyd Steinberg dithering:

The flipped screen:

Devilmarkus · 20:28, 18 June 10

Perhaps someone is able to build a flickerfixer interface to put between CPC monitor output and CTM?
(smiling to Bryce)

Leonie · 22:09, 18 June 10

Quote from: Devilmarkus on 20:28, 18 June 10
Perhaps someone is able to build a flickerfixer interface to put between CPC monitor output and CTM?
(smiling to Bryce)

Dear Bryce, dedigitate!
The world waits!

Devilmarkus · 09:21, 19 June 10

To reduce flickering I use a simple trick:
I split both images and merge their lines.

The result on a de-interlaced screen is the same.
On a CTM it's much better viewable now.

Demonstration as GIF:

Sad, that GIF only provides 15 fps

All is done with JavaCPC-Paint:
Put screen as image A: Press "1" in emulator display while painting
Put screen as image B: Press "2"...
Flip screen preview: Press "3"
Restore image A to paint: Press "4"
Restore image B to paint: Press "5"
Split both images as seen in example above: Press "6"
Important: both screens must have the same palette and screenmode.

Gryzor · 11:29, 19 June 10

This is seriously great! It's a pity you can only use it with static images. But still, there are games that are suited to it - like Leonie said, a Strip Poker would look great. Maybe redo Teenage Queen?

Devilmarkus · 12:04, 19 June 10

4 flipscreens for you to try:
[cpc=http://cpcwiki.eu/forum/index.php?action=dlattach;topic=804.0;attach=705,DISC,1]CPC6128[/cpc]

Leonie · 12:23, 19 June 10

Quote from: Devilmarkus on 09:21, 19 June 10

I like that flicker somehow.
Reminds me of the "helmet-camera-view" in the film "Alien".
We should remake the Alien-Game! Nice Adventure!
"Aliens" from Electric Dreams would be great too...
...and a strip-poker like "Samantha Fox Strip Poker"!

Devilmarkus · 13:59, 19 June 10

Sad that we only have a few kb free on each disk...
Animations could look cool:

Devilmarkus · 14:38, 19 June 10

Here's a small one for Leonie:

98 frames, MODE 0

Devilmarkus · 17:22, 19 June 10

BTW.: these "movies" are real CPC screens!
Only thing: They are stored and called internally in emulator.

Example how I make such animations:
http://cpc-live.com/capture/
(Don't watch it, if you are under age of 18!)

Leonie · 17:55, 19 June 10

Quote from: Devilmarkus on 17:22, 19 June 10
Don't watch it, if you are under age of 18!

Devilmarkus · 20:14, 19 June 10

Quote from: Leonie on 17:55, 19 June 10

Hmmmmmm don't cry

978 frames: http://cpc-live.com/cpc_movie/

Devilmarkus · 20:40, 19 June 10

Some secret info:
Someone is working on a HD-playback routine for those movies

So users with HD connected to CPC will be able to watch those movies someday...
(Or SD-card reader?!)

Leonie · 21:46, 19 June 10

Quote from: Devilmarkus on 20:14, 19 June 10
978 frames: http://cpc-live.com/cpc_movie/

Fits that on one disk or tape?

voXfReaX · 21:46, 19 June 10

Hello there!
I have seen the flip-screens of Markus and I have to admit that I am interested as well...
Although all pictures are nice, I really enjoyed the one with the 76 colors!
Is it possible to see it in a real CPC? I am really curious of the quality...
(...and to be clear, i do not question Markus' abilities, I am just questioning the quality of the image on a real monitor!)
we speak,
voxy

mr_lou · 06:56, 20 June 10

I've seen some of Markus' flipscreens on my real CPC.

The first ones in this thread had way too much flickering, because the colors shifted between very bright and very dark. I think a lot of people would get an epileptic seizure when looking at those.

Then he made some where the two images used the same palette. Here flickering was noticeable, but not much more than that. They look rather neat actually. The downside is of course that the image will look a little bit monotone still, because both images contain the same colors, which have the same brightness/contrast level. This means the picture will look kinda old, which isn't necessarily a bad thing. The colors will, although appear to be different shades, stay within a limited area of the spectrum, if you can put it like that.

What we still haven't seen, is a mix between method 1 and 2. A method 3 that uses two MODE 1 pictures, with 2 different palettes, but where the colors are still not too far apart. E.g. color 6 on image 1 mixed with color 0 on image 2 would give a color 3'ish result.
But creating two images like that requires some extra effort compared to using the first two methods. I think it should be started by choosing the 2 different palettes. Meaning 2x4 colors. Then mix all 8 colors. Theoretically that should give you over 30 colors, but only a few of them will give a minimal flicker.
Calculating the palettes is easy however. Switching between color 6 (0xFF0000) and color 0 (0x000000) will logically give a color 3 (0x7F0000). But switching between those two colors will give too much flicker in my opinion. So as a ground-rule for this, the max different in each RGB value of the two colors to be mixed, must be 0x7F. I think 0xFF gives too much flicker, but I suppose there'll be exceptions between two brighter colors.

One simple way of checking out how much flicker two colors will give, is to do a simple
INK 0,color1,color2
BORDER color1,color2
SPEED INK 1,1

It's easy to see that color 0 and color 3 gives less flicker than color 0 and color 6. It's also logical.

Meanwhile, method 2 might give even less flickering if the setting-inks was dropped between each image. I suspect the code I've seen was still setting the 4 inks for each switch. It'll probably not be that noticeable though.

Devilmarkus · 08:39, 20 June 10

Quote from: Leonie on 21:46, 19 June 10
Fits that on one disk or tape?

LOL this "movie" is 15.2mb large

It would fit on a harddisk or SD card...

Quote from: voXfReaX on 21:46, 19 June 10
Hello there!
I have seen the flip-screens of Markus and I have to admit that I am interested as well...
Although all pictures are nice, I really enjoyed the one with the 76 colors!
Is it possible to see it in a real CPC? I am really curious of the quality...
(...and to be clear, i do not question Markus' abilities, I am just questioning the quality of the image on a real monitor!)
we speak,
voxy

The 2nd method I use looks much better on real CPC's. (As mr. lou already mentioned)
The good thing: this method is implemented in JavaCPC-Paint later, so you can produce those screens easily with a few mouse clicks and key presses.

Devilmarkus · 10:38, 20 June 10

Small movie for you:
[cpc=http://cpcwiki.eu/webcpc/movie2.anz,none,0]CPC6128[/cpc]

OCT · 16:26, 20 June 10

IIRC there was a piece of code in German mag CPCAI once to combine MODE 0 colour bars with MODE 2 text, i.e. flipping resolutions on vertical synchronization.
On CRTs of the day, the result was flickering unbearably, of course - but it may look better on LCDs.

Devilmarkus · 09:20, 21 June 10

Just for fun:
http://cpc-live.com/takeonme

YM file + video

Devilmarkus · 14:04, 21 June 10

The GUI for creating videos is quite easy to handle:

It will be a new feature just for fun in next JavaCPC

And, perhaps, somedays, a player for real CPC exist, too...
Theoretically it could be possible.

Gryzor · 08:04, 22 June 10

Don't know what to chuckle more with, the vid or the tune

Noncorpus · 08:44, 01 June 14

sorry to bring this thread back to the surface.. but i thought i'd mention that when i was working with flashing colours i made a kind of fractal pattern to show which were the least flickering combinations to get the extra 98 colours

Noncorpus · 23:25, 06 June 14

Actually, this first one i made is probably more suitable for flip screens.. and that one i posted first is more for dithering.

as for these flip screens.. i have managed to separate the colours and interlace the 2 screens manually with paint shop pro.. but i wouldn't have a clue how to make that binary file that loads before the images.. i can use the ones on the flip test disk.. but then i am limited to those modes and palettes..

I wouldn't mind being able to.. I might need a hint..
(I am fine with the Basic programming though)

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Flip screens on CPC / Emulator