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Author Topic: Non-standard graphic modes (Read 676 times)

Offline ssr86

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Non-standard graphic modes
« on: 2015.September.22. 22:59:23 »
Saw a movie about atari software-driven graphic modes. Maybe some technics that are used on the atari could be utilized on the ep... Atari seems to also use something like the lpt (display list). Although I guess that some will use sprites for coloring up...

First "software-driven" (I don't know if I can say that) modes I could list are the "square-pixel" (well don't have to be "square" - just vertically stretched) modes like I'm trying to use... (atari seems to have the 4 color variant. Game "Yoomp!" uses it https://www.youtube.com/watch?v=UqmyLKG1l-4).

Someone knows about another?
"Interlace demo" mode counts...
Zozolace demo has another one too...
Changing palette at every scanline (fix bias every two) could also count as such mode, I guess...

I think that one of such atari modes uses vbi to switch between two character sets every frame to get the illusion of more colors... Well actually wuoting the author:
"In my game "Gem Drop", I used a simple VBI to flip between two character sets (no palette changes or DLIs) to give the illusion of 13 colors in ANTIC 4 mode."
https://en.wikipedia.org/wiki/Software-driven_graphics_modes_for_the_Atari_8-bit_computers
« Last Edit: 2015.September.22. 23:24:51 by ssr86 »

Offline endi

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Re: Non-standard graphic modes
« Reply #1 on: 2015.September.23. 21:12:35 »
square pixels and per rasterline coloring is used in some games, coloring is great on specy conversions too (there are some very nice ones)

for example my game with square pixel 256 color mode (see the animgif)
http://www.ep128.hu/Ep_Games/Leiras/Book_of_Life.htm



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