Jump to content
chewy

Hack idea for Threshold (Tigervision)

Recommended Posts

good shooter, but the scrollling sidegrapics are making me dizzy and seasick (seroiusly!- been getting a little eye fatigue from some of these games lately lol)- anyways- my hack idea is to have get cut those side walls out of the code............

Share this post


Link to post
Share on other sites

You are using the portable version, right?

 

Sounds like an easy change. First guess is to remove the playfield pixels altogether...by altering $F6AC to read LDA #$00 instead of #$C0...

post-222-0-23652300-1554633637_thumb.jpg

 

Unfortunately, that PF1 is hiding the inactive bad guys from view. So instead of that, alter $F6A8 to read LDA #$00 (A9 00) instead of LDA ram_B3 (A5 B3)...the PF color is changed to black.

 

The game recolors playfield on later scanlines, tho. So you need to change $F78C from ORA #$04 (09 04) to be LDA #$00 (A9 00) as well...

post-222-0-76123400-1554634095_thumb.jpg

 

But there's another problem. The enemies use the ball sprite to fire on the player. With PF set to black, the ball is no longer visible.

 

So you either have to put up with the inactive enemies being visible, or make a more-extensive hack which changes the sprite used for enemy missiles.

Edited by Nukey Shay
  • Like 1

Share this post


Link to post
Share on other sites

You are using the portable version, right?

 

Sounds like an easy change. First guess is to remove the playfield pixels altogether...by altering $F6AC to read LDA #$00 instead of #$C0...

attachicon.giftg1.jpg

 

Unfortunately, that PF1 is hiding the inactive bad guys from view. So instead of that, alter $F6A8 to read LDA #$00 (A9 00) instead of LDA ram_B3 (A5 B3)...the PF color is changed to black.

 

The game recolors playfield on later scanlines, tho. So you need to change $F78C from ORA #$04 (09 04) to be LDA #$00 (A9 00) as well...

attachicon.giftg2.jpg

 

But there's another problem. The enemies use the ball sprite to fire on the player. With PF set to black, the ball is no longer visible.

 

So you either have to put up with the inactive enemies being visible, or make a more-extensive hack which changes the sprite used for enemy missiles.

 

 

HEY MY GUY- THANKS SO MUCH FOR "FIXING" IT- i forgot i posted this but then i got frustered with threshold again and i remember and i was pleasntly suprised to see all your info, and the steps you took. I am playing on a sunnyvale light 6'er via harmony cart

Share this post


Link to post
Share on other sites

soooooo much better. maybe im overly sensitive to this stuff but i was getting motion sick playing this one- you made the suffering stop

  • Like 1

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...