dwhyte Posted September 12, 2007 Share Posted September 12, 2007 How would I go about stopping a dli partway through the scanline?... Horizontal color bars or blocks is what I'm trying to accomplish on a mode 2 screen... Quote Link to comment Share on other sites More sharing options...
Shawn Jefferson Posted September 12, 2007 Share Posted September 12, 2007 (edited) You can't really stop a DLI partway through a scanline (well, I guess you can just return from it, but I don't think that's what you mean.) You could do something like: lda #xx sta wysnc sta $some_color_reg nop nop nop etc.. then change the color back, which would give you a color bar. Alternately, you could use PM graphics to make your color bar, or just draw it on the screen, but I'm guessing since you are asking about a DLI that you are already using the standard drawing techniques and want "something more". Edited September 12, 2007 by Shawn Jefferson Quote Link to comment Share on other sites More sharing options...
dwhyte Posted September 12, 2007 Author Share Posted September 12, 2007 (edited) Alternately, you could use PM graphics to make your color bar, or just draw it on the screen, but I'm guessing since you are asking about a DLI that you are already using the standard drawing techniques and want "something more". Yeah what I mean is colored columns on a mode 2 screen. Like the second modeline in Whiskey-Mon... I'd just disassemble the code, but I need someone to describe the process to fully understand it... Edited September 12, 2007 by dwhyte Quote Link to comment Share on other sites More sharing options...
Rybags Posted September 12, 2007 Share Posted September 12, 2007 PMG overlays are your best bet if you want different colours by columns. You can "chase the beam" and effect changes at a cycle level but it is tricky and very time consuming since it has to be done on every line. Plus, it isn't really possible in 40 column text modes since all of the cycles in the visible area are stolen by ANTIC on the first line of each character. Quote Link to comment Share on other sites More sharing options...
dwhyte Posted September 13, 2007 Author Share Posted September 13, 2007 PMG overlays are your best bet if you want different colours by columns. You can "chase the beam" and effect changes at a cycle level but it is tricky and very time consuming since it has to be done on every line. Plus, it isn't really possible in 40 column text modes since all of the cycles in the visible area are stolen by ANTIC on the first line of each character. So how is something like this possible then? It can't all be pmg-ol's or pmg-ul's... What registers do I need to examine to make such changes? Are they in the DLI or VBI or main code to enact such changes to the screen? I could for the most part use pmg's for certain columns, but, it wouldn't exactly be the effect I'm trying to do... Quote Link to comment Share on other sites More sharing options...
gauntman Posted September 13, 2007 Share Posted September 13, 2007 So how is something like this possible then? It can't all be pmg-ol's or pmg-ul's... What registers do I need to examine to make such changes? Are they in the DLI or VBI or main code to enact such changes to the screen? I could for the most part use pmg's for certain columns, but, it wouldn't exactly be the effect I'm trying to do... Actually, that looks pretty much like PMG. Remember, that when all 4 players + the 4 missiles are set to wide, 1 pixel in the PMG will cover 1 Antic 2 character. So, with all 4+1 players, you can cover the entire screen. If I wanted to duplicate something like the picture above, I would use P0+P1 for the first light blue column, then use a regular DLI to handle the color changes on the right hand column. Quote Link to comment Share on other sites More sharing options...
dwhyte Posted September 13, 2007 Author Share Posted September 13, 2007 So how is something like this possible then? It can't all be pmg-ol's or pmg-ul's... What registers do I need to examine to make such changes? Are they in the DLI or VBI or main code to enact such changes to the screen? I could for the most part use pmg's for certain columns, but, it wouldn't exactly be the effect I'm trying to do... Actually, that looks pretty much like PMG. Remember, that when all 4 players + the 4 missiles are set to wide, 1 pixel in the PMG will cover 1 Antic 2 character. So, with all 4+1 players, you can cover the entire screen. If I wanted to duplicate something like the picture above, I would use P0+P1 for the first light blue column, then use a regular DLI to handle the color changes on the right hand column. Ingenious!!! As you can tell by this post I've never really used PMG's before. I've been reading De Re Atari about them and didn't think you'ld be able to cover a screen that well with them... Thank you very much... I'm by far no expert atari coder, but yet one day I'll be close to being one with all these little gems of knowledge that are passed around this board... Quote Link to comment Share on other sites More sharing options...
Rybags Posted September 14, 2007 Share Posted September 14, 2007 Hint: you will also save memory if you stuff the GRAFPn registers directly. Just set them all to $FF, then use the DLIs to change their horizontal positions and colours. Quote Link to comment Share on other sites More sharing options...
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