Missing PF collisions during HMOVE blanks

[thrust26]

The missile is positioned at 8 and moved to 0 and back to 8 during HMOVE. The leftmost pixel of PF0 is enabled. So there should be a collision happening as it does on real hardware.

The attached test program shows the bug.

TestCXM1.zip

[sa666666]

No other emulator I tested (Stellerator, z26, Javatari, MAME) gets this right either.

[thrust26]

No big surprise. There are four things which must come together:

1. HMOVE blanks
2. playfield inside these blanks
3. an object close to the right of the blanks
4. a collision check between playfield and the object.

I only found this by accident, because the missiles in my new Robot City game didn't work on my Vader. And only because I needed some tricky code to display the fuel bar at the bottom.

[sa666666]

Forgot to add; also confirmed on my light sixer and Jr.