apple2video: fix ivelultr/dodo/laser2c text rendering

[arekkusu42]

(followup #14999)

This PR fixes text rendering on ivelultr/dodo/laser2c: these clones display text characters shifted one pixel too far to the right, which is mostly visible with INVERSE text:

After this PR, text rendering aligns with other Apples and clones:

I don't have direct experience with these clones, but it also matches the references I was able to find online:

• This video (using ASCII not YU, so C with caron "č" appears as "~") shows inverse "D" and "_" character spacing on IVEL ULTRA hardware
• The original thread dumping dodo ("GTAC Wiederbelebung" "Do-Do") contains a photo showing the cursor spacing on hardware
• This video shows cursor spacing on Laser ][c hardware

This PR also cleans up the screen_update() and text_update() template instantiation to match what is actually used.

Code comments:

Details

Auditing the various apple2 character ROMs shows there are three classes of text bitmap layout (plus inversion):

1. flip: all apple2 EXCEPT ivelultr/dodo/laser2c, and spectred/ace500/2200
2. shift & flip: ivelultr/dodo/laser2c
3. no flip: all apple2e EXCEPT spectred/ace500/2200, and apple2gs

The shift case was briefly handled by an Invert, Flip template combination, but this broke when apple2gs changed to use Invert, so is now handled with explicit a2_video_device::models. That's fine. But the shift by >> 1 wasn't enough.

>> 2 works for all characters except 0xFF which fills all 7 bits in ivelultr (ASCII page) and dodo ROMs. I don't know how IVEL ULTRA hardware implements this, but based on the reverse engineering of a different GTAC clone, it's likely that the chargen shifters keep all 7 bits and just swizzle the order. So this code rotates bit 1 into bit 6, such that character 0xFF properly fills all seven pixels.

For the instantiation cleanup, there are four fixes:

1. <II, true, false> is now replaced by <DODO, true, false>
2. <II, false, false> was only used by superga2 and tk2000, which have no text modes, so make them match apple2p and delete the unused instantiation
3. <IVEL_ULTRA, false, true> was briefly added for albert, but is now unused
4. make text_update() match screen_update()

Removing unused instantiations shrinks a clang arm64 release (O3, no LTO) binary by about 4kB.

TODO:

Details

I noticed a few other things while auditing:

• It's unclear why craft2p is marked IMPERFECT GRAPHICS. The char ROM has two language pages, but they are both Portuguese. Is it dumped incorrectly?
• ivelultr is commented as "wider character cell" but the video hardware uses regular 7x8 cells, only the alignment of the ROM bitmap differs, which this PR fixes
• pravetz8m_chr has four language pages. There is an unemulated dip switch but I haven't found documentation on it.
• It's unclear how to toggle language pages on tk3000 or laser128*

[ajrhacker]

It's unclear how to toggle language pages on tk3000

On tk3000, that can be done by pressing the Mode key. The effect can be seen in this video of actual HW: https://www.youtube.com/watch?v=ZnpTV49uizc

It's unclear why craft2p is marked IMPERFECT GRAPHICS

I just checked again, and the way flashing/inverse characters are handled looks wrong for this system.

[arekkusu42]

Thanks! I had seen the "mode" key in the tk3000 manual, but now I also see that it is mapped to F11. Works fine.

craft2p: OK, the references I could find only showed normal text.