Lots of blank space at bottom of screen

[+Gemintronic]

So, in some of my games there's a noticeable surplus of blank space at the bottom of the screen compared to the top.  In standard kernel games sometimes adjusting the playfieldpos variable helps.  But, in the multi sprite kernel it does nothing. 

 

Any clue as to what is causing the bottom to have more blank space?

 

I set screenheight to 80 and pfheight to 7 so I can save ROM.

 

 

atarogtwo001.bas

 

[KevKelley]

1 hour ago, Gemintronic said:

So, in some of my games there's a noticeable surplus of blank space at the bottom of the screen compared to the top.  In standard kernel games sometimes adjusting the playfieldpos variable helps.  But, in the multi sprite kernel it does nothing. 

 

Any clue as to what is causing the bottom to have more blank space?

 

I set screenheight to 80 and pfheight to 7 so I can save ROM.

 

 

atarogtwo001.bas 1.34 kB · 0 downloads

 

I know when I was messing with some things with the SueprChip RAM, I notice this as well where I was playing around with screenheight and pfres, as well as changing how many rows are in my playfield and noticed that I too had a blank spot at the bottom and when I adjusted I got more  seemed to get more space back. Part of me was wondering if my mind was playing tricks on me.

 

As for why this occurs I have no idea other then I thought making a combination of these changes would squeeze a bit out of the kernel.

 

The shorter screen (01_23) has a 39 row playfield with these settings:

    const screenheight=88
    const pfres=32
    pfheight=1

The taller screen (01_25) has a 43 row playfield with these settings :

    ;const screenheight=88
     const pfres=32
     pfheight=1

 

Here is a pic of each for comparison:

Edited June 14, 2022 by KevKelley

[+Gemintronic]

Interesting!  By leaving out the

 

    const screenheight=8x

 

and adding a mini kernel it evened out the screen.  Don't understand why excluding specifying the screen height centers things.  I have much to learn!

 

 

[KevKelley]

I only came across is by just playing around, adding and deleting stuff out of boredom and for experimenting. And as far as I could tell it didn't negatively affect the game.