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pmc · 13 April 2007, 22:58

Thanks for taking the time to go through my undoubtedly amateur source code - all your help & advice is appreciated!

I have had a version of the code running where I tested the get_char routine and proved it grabs the characters from the font bitmap properly cos I blitted into the displayed screen so I could see the result.

I also did the same thing with the scoll part (I scrolled a chunk of the displayed bitplane) but my code as it is did weird things so I need give that part some more thought.

I'll try to pick apart all the bits of advice you've noted down and see if I can get the code edited accordingly...

Even though there are big errors in the code that need to be corrected, am I on the right track as far as the actual method for getting a sinescoller working goes?

In particular I wasn't sure about the sine copy part, the way my thinking went on this was to grab a word width chunk of the scrollplane, mask off 15 bits of this word, so I could blit just one line of the data into the displayed screen, and repeat this blit of the same word 16 times, each time masking off different bits and adding the next y value from the sine table before moving onto the next word of the scrollplane and repeating. Is that in the right ball park?

13 April 2007, 22:58	#11
pmc gone Join Date: Apr 2007 Location: completely gone Posts: 1,596	Thanks for taking the time to go through my undoubtedly amateur source code - all your help & advice is appreciated! I have had a version of the code running where I tested the get_char routine and proved it grabs the characters from the font bitmap properly cos I blitted into the displayed screen so I could see the result. I also did the same thing with the scoll part (I scrolled a chunk of the displayed bitplane) but my code as it is did weird things so I need give that part some more thought. I'll try to pick apart all the bits of advice you've noted down and see if I can get the code edited accordingly... Even though there are big errors in the code that need to be corrected, am I on the right track as far as the actual method for getting a sinescoller working goes? In particular I wasn't sure about the sine copy part, the way my thinking went on this was to grab a word width chunk of the scrollplane, mask off 15 bits of this word, so I could blit just one line of the data into the displayed screen, and repeat this blit of the same word 16 times, each time masking off different bits and adding the next y value from the sine table before moving onto the next word of the scrollplane and repeating. Is that in the right ball park?