The Upward Spiral - tile drawing ALMOST perfect

RSS Bot · May 16, 2006

Last night's efforts. Ignoring the rest of the screen, which I've blocked out for the moment, notice that these trees are drawn "perfectly." Every PF2 hit is exactly on cycle, and the HMOVEs also. (There's an HMOVE on every scanline, but always at cycle 73.)

The rest of the screen is fouled up because my "bad line" (triplet 7 line 2 on each row, i.e. scanline 24 of each 24-scanline row) is still not cleaned-up. Now that I have the timing "perfect," though, I can try to re-arrange some of the tasks from 7,2 into the SLEEPs in other lines :-D

I actually have an 8-cycle sleep that I completely lack understanding as to why it's needed... but hey, if it works, it works. It has to do something with the interleaving of 24-line rows, 8-line x 3 playfield graphics, and 12-line x 2 player graphics, and my total discomfort in working with figures.

To get the timing right I'm afraid I used the "tube of toothpaste" method. "squeezed" in extra SLEEPs on line (0,0), then (0,1), then (0,2), working my way up to about (2,0) before the other lines snapped into place (excepting (7,2) of course).

Ironing out the joystick code tonight and possibly augmenting the sound code slightly. A musician friend of mine (thanks Natalie!) saw some animatics I'd sketched out and noticed my use of musical repeat notations - ||: | - and the discussion reminded me that I could maybe support such repeats in the sound code to compress the music better.

The combat kernel is mostly intact on my iMac, I've got to merge it back into the Subversion fold though. The kernel (notably) lacks some major functions, notably: there are no animated attacks yet (horrors!)... the attacks have no actual effects (HP/MP aren't changed)... and monsters don't animate individually. (All monsters on screen animate in lock-step. You know... NUSIZ clones.) Oh... and equipping items/magic doesn't work through the UI. I've been tweaking ZP locations in Stella, which is probably not the best UI ever.

Ursa's basically done, tile drawing's almost done, combat kernel gets some TLC next and then I get to point at Mayday and take a nap for a while. But instead I'll probably hack up some cool magic and attack animations and work on stuff like the stats display (easy, but annoying), the save/load game code for Avox/memcard (where did I stash that MemCard during the move!?), and the attraction mode and "you win" animation sequences.

I've toyed with the idea of giving Ursa some controls to do "Macromedia Director" type animation controls, like, "move P0 in a line to location (x,y) doing alternations every (n) deciseconds between bitmaps (a) and (b)" to do the attraction and winner kernels and possibly (gasp!) a cut scene? ... but that kind of candy should probably wait. It depends on whether I think I can pull it off more easily using Ursa or 6507 assembly... and which takes less ROM space.

BTW, don't think I "blogged" this before, but all animations and fx are based on a decisecond timer. Unfortunately I did have to go for NTSC/PAL conditional compilation. The NTSC version naturally has 6 frames per dsec, the PAL,SECAM version only 5, and the music generator "mksound" -- which is abyssmal, right now, I really should work on it, too! -- writes conditional-compilation AU* register triplets out. Also, all colours are registered with conditional-compilation NTSC v. PAL colours, and the SECAM colours are used as the B&W values. This does mean that if you trip the B&W switch on the console the screen will look kinda trippy on colour TV, but, it'll be playable on a B&W set.

Aside: I was playing another author's homebrew on my B&W test set and was brutally murdered by invisible enemies on about the 4th level, not realizing that their colour was nearly the playfield colour Of course, I may be the only one who'll ever see "CiE" on a B&W set... Hey! it's "colourblind mode!" There ya go. I knew it was practical.

Oh, nearly forgot: here's the goodies!

http://www.atariage.com/forums/index.php?a...&showentry=1559