Heaven/TQA Posted September 22, 2004 Share Posted September 22, 2004 hmmm... i spend some time in searching atariarchives for a vscroll routine but haven't found any suitable... diggin into river raid wasn't good either as the whole screen is done with antic e.... can someone post a vscroll routine here like used in flak!, warhawk! etc??? i just used the other way around (caverns of mars...) but this does not work for the other direction... aarg... as demo coder i always coded hscroller... oh of course for atari800.... Quote Link to comment Share on other sites More sharing options...
Schmutzpuppe Posted September 22, 2004 Share Posted September 22, 2004 Trackball uses vscroll so I don't really understand what you are looking for!? Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted September 22, 2004 Author Share Posted September 22, 2004 my routine misses 1 frame and that's why it isn't smooth on atari800win... or is it smooth on real hardware??? Quote Link to comment Share on other sites More sharing options...
Schmutzpuppe Posted September 22, 2004 Share Posted September 22, 2004 I would think that this is an emulator "issue". It looks quite smooth if you switch the emu to NTSC. Didn't had the chance to test it on real hardware. Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted September 22, 2004 Author Share Posted September 22, 2004 you can notice the flicker when watching the background tiles... i'll double check that on real hardware... but maybe you can post your vscroll routine? i try to recode the scroll engine tonight with a kind of "positioning" approach so you have a "level position pointer" and the engine positions the window based on this pointer... at the moment it's kind of "incremental" one... with this generic vscroller more interesting things will be possible... like running backwards etc... Quote Link to comment Share on other sites More sharing options...
Schmutzpuppe Posted September 22, 2004 Share Posted September 22, 2004 Ok, I know what you mean. The attached modifications solves your problem. Additionaly you can change the scrolling direction now by writing 1 to scldir ($85) but this just concerns the finescolling part you have to handle the do_scrolling0 also if you wanna do this. There is only one disadvantage, the code is 1 byte longer trackb1.zip Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted September 22, 2004 Author Share Posted September 22, 2004 thanks! i'll check it out... but this 1 byte longer doesnt care... have you realised that i used a complete 2nd routine for building the 2nd screen??? why did i not just copy the 1st generated line to the 2nd screen... just realised that yesterday... so ggen_gfx changed to a simple: ggen_gfx ldx #39 ggen_gfx0 lda (linev),y sta (linev2),y- bpl ggen_gfx0 rts and this saves a lot more bytes... Quote Link to comment Share on other sites More sharing options...
Schmutzpuppe Posted September 22, 2004 Share Posted September 22, 2004 No I didn't realize that because I don't take a deeper look at the code. I am sure you will find more optimization every time you'll look at the code. But in this case time is the problem... Quote Link to comment Share on other sites More sharing options...
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