SpiceWare's Blog - TV Type option

RSS Bot · April 17, 2014

I migrated the color conversion routines from Timmy! so you can now select your TV Type of NTSC, PAL or SECAM from the menu. Because of the limited menu space, due to that snazzy logo up there, I did not copy over the RED/GREEN/BLUE menu entry - so use the green station in the logo to confirm your selection.

You can use Stella to try out the different TV-Types. Hit <CONTROL>-F to step between the different formats. Make sure to use modes PAL60 and SECAM60 instead of PAL and SECAM.

NTSC

PAL

SECAM

It's quite noticeable if the wrong TV Type is selected:

NTSC selected on SECAM system

PAL selected on NTSC system

SECAM selected on PAL system

One of the things I'd planned to do was compensate for the non-square pixels. Nathan did up these graphics to show how the diagonal shots in Draconian line up (in red) vs how they should line up (in green) based on the 45° ship image:

I made the changes to compensate for the non-square pixels, but was not at all happy with the results. Main problem was it caused a serious case of judder whenever you would fly left/right. As a minor issue it also made the auto-repeat pattern different when firing left/right vs diagonally or up/down. I decided the judder problem was bad enough that I removed the compensation routines. If you'd like to see it for yourself, try the judder ROM below. What you'll see is the objects that should move in lockstep with each other (asteroids, mines, the enemy formation) will frequently move towards then away from each other as they pan across the screen.

We'll end up redoing the ship image similar to how Time Pilot's ship is angled so that it lines up with the actual diagonal shots (in red).

If you're checking this out with Stella, be sure to turn on phosphor mode!