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Gray experiment utility

PostPosted: Fri Nov 07, 2014 5:32 pm
by Drakker
Source and HEX available here: http://drakker.org/gamebuino/gray_experiment/

This utility is a test of multiple ways to display gray. You can select the type of gray using the left and right buttons and adjust the FPS with the up and down buttons.

Findings so far:

    - Gray displays differently from screen to screen (already known).

    - Gray is pretty much a crap shoot (already known).

    - FPS doesn't seem to matter much, depending on the display. Some combinations of screens and gray types work just fine at 15fps.

    - Some patterns of gray have an impact on the whole display, on all my screens the horizontal striped gray made the text at the bottom of the screen gray too, while it is not.

    - Checkered gray seems to work the best on all 3 of my displays.

    - More to come later...

I would like to get some feedback, if you guys can try it out and report on what type of gray works best/worst on your display and at what FPS, maybe we can figure out a gray pattern that is usable.

Re: Gray experiment utility

PostPosted: Thu Dec 11, 2014 9:41 pm
by quosa
Well DONE! After testing with your utility - decision is done: checkersmall1 ;)

Re: Gray experiment utility

PostPosted: Thu Dec 11, 2014 10:41 pm
by Drakker
Great, thanks for trying it and reporting your findings. Seems like checkered is the way to go for gray. Did you get the blinking text at the bottom with the horizontal striped gray?

Re: Gray experiment utility

PostPosted: Mon Dec 15, 2014 11:54 pm
by Sushi
No, did you? I've replaced my display three times, and I'm using the best one I've come across, so maybe it's your display if you're getting flashing.

Re: Gray experiment utility

PostPosted: Tue Dec 16, 2014 12:58 am
by erico
I should be giving this a go a bit after 20th now...interesting proposal!

Re: Gray experiment utility

PostPosted: Tue Dec 16, 2014 3:23 pm
by Drakker
I got the text flickering with the horizontal striped pattern on all 3 of my displays, but one of them is ghosting so badly that nothing looks right on it anyway.

Re: Gray experiment utility

PostPosted: Tue Dec 23, 2014 6:45 pm
by erico
checkered above 26-27 seems to produce ok results here with an ocasional stripe going around at a slow speed.
No blinking texts whatsoever.

the filled type seems to be even able to produce different types of lighter grays but they have a bigger stripe going vertically.
Somehow it seems that a value in between 20-22 or 40-42 could stabilize such.
is there a way to use something like 41.5? or increase it by .25?

Re: Gray experiment utility

PostPosted: Tue Dec 23, 2014 8:10 pm
by Drakker
For that I'd have to check the code for the Gamebuino library, all the examples from Rodot use integers, but by modifying the library, it is probably possible to use milliseconds per frame instead of frames per second. I'll check that out in the next few days.

Re: Gray experiment utility

PostPosted: Tue Dec 23, 2014 10:42 pm
by erico
Nice. It kind of reminds me of recording video images back in the days. Things needed a precision sync that was sure very "float point" not to band. Maybe we have a similar situation? Is the exact refresh rate of gamebuinos screen at 20? Or is it something like 19.98?

Re: Gray experiment utility

PostPosted: Tue Dec 23, 2014 11:31 pm
by Drakker
According to Myndale it is roughly 41 fps.