Jump to content
Posted Wed Feb 16, 2005 1:07 PM
Posted Wed Feb 16, 2005 1:17 PM
Maybe, but then we did also only discuss again what other guys already had dicussed many years before.
It's starting to sound like you guys have already discussed everything a couple of years ago.
Posted Tue Oct 25, 2005 5:02 AM
Posted Tue Oct 25, 2005 5:20 AM
sta WSYNC sta HMOVEafter that code?
Posted Tue Oct 25, 2005 5:50 AM
Posted Tue Oct 25, 2005 11:47 AM
It is important that you write to HMOVE *directly* after WSYNC. WSYNCs at the end of the subroutine are superfluous.
I was writing to WSYNC at the end of the subroutine..
and then writing to HMOVE after both subroutine calls.
I've changed it so that I do both writes after the subroutine calls and it works, thanks.
Posted Sun Nov 2, 2008 10:29 AM
I don't think its ROM amount per-se I think it is amount of cycles to acheive task. The less the better. The more elegant, the more you can do per scanline.
It is true that assuming the pixels on screen are numbered 0 to 159, then placing the corresponding value in A and calling this routine will not position object at the expected pixel.
My feeble mind had given up trying to figure out things like Xreal and K
Instead, I just use a table. 160 bytes of overhead, but simple enough to grasp. When you get involved with bankswitching, it's not like rom is scarce or anything
Posted Sun Nov 2, 2008 10:56 AM
Edited by grafixbmp, Sun Nov 2, 2008 10:58 AM.
Posted Wed Apr 20, 2011 8:14 AM
Posted Wed Apr 20, 2011 10:12 AM
I'm putting adapted versions of these sessions on my web site. Does the information in the first post need to be updated with anything that has been posted in this thread? I know almost nothing about assembly language, so I can't tell.
ldx #0 txa Clear dex txs pha bne Clear
since the tsx and pha don't affect the flags,
Posted Wed Apr 20, 2011 2:22 PM
There's a typo. . .
Posted Wed Apr 20, 2011 3:03 PM
For repositioning outside the kernel usually the nice code rediscovered by Cybergoth in Battlezone code IMO is optimal.
There are usualy 2 basic types of h positioning code.
One that does it before the screeen start as in one for each sprite per screen and one that is able to do it multiple times during the screen if a sprite is reused. idealy both.
Edited by Thomas Jentzsch, Wed Apr 20, 2011 3:25 PM.
0 members, 0 guests, 0 anonymous users