Three tunes

Having three different visual environment for Bilou's Dreamland's first demo is one thing. I'd like to given them distinct musical background, too. That was last week-end's target, but unfortunately, it hasn't been very satisfying.

Sure, I could get 'school rush' theme played while being in the school room, and 'Apple Assault' theme while being in the green room (sic), but the loading time between them became quite excessive. Even if I expect this to happen only at 3 different time in the game, being completely silent and blank then is a no-go.

The second issue is with sound effects. Apple Assault used simple samples to play sound effects for e.g. jumps, stuns and the like. School Rush instead had mini-patterns with 3-4 tracks to produce the desired arpeggios and effects from ultra-basic sound palette. Of course the green zone tune did not featured any of this.

 The third and final(?) issue is an endless loop within the memory manager. Most likely, something's wrong within libNTXM memory management (or in my messed' up clone of it) which never showed up since I was playing the same module over the whole game's lifetime in previous installments.

Eh bin ... ça en a fait, des choses à fixer pour pouvoir passer d'une musique à l'autre au sein d'un même programme basé sur GEDS. Entre les makefiles, la bibliothèque NTXM elle-même, les p'tits soucis de parser et les modifications à apporter aux scripts, heureusement que TortoiseHg était là pour déméler tout ça au moment de faire enfin des commits.

C'est encore hautement perfectible, notamment au niveau des temps de chargements, mais si je veux avoir une première version jouable de Dreamland d'ici la fin des primaires de J.L.N., il va falloir que je me concentre d'abord sur le reste.

So I've been trying to see where I could have poorly managed memory ... something that would explain how the loop appeared, but given how shielded the memory management code already was in libntxm, I started doubting of my own deductions.

Then the emulator suddenly decided to give me addresses and register dumps! Huzzah!... but they were all for the ARM7 core.

It turned out that, no matter whether you invoked NTXM9->stop(), the timer interrupt keeps running and it keeps checking for the NTXM7->song pointer and dereference it. Simply, all channels are turned to mute, or something alike when you've stopped the playback on the ARM7. Note that background color for the top screen turns to weird orange when this occurs.

And of course, the ARM9 code would delete() that song before it sends the 'set song' command to the ARM7, meaning that the ARM7 core would start using recycled content to guide how it should work (including objects and VPTRs!) ... Pretty weird to see shared virtual tables between the two co-processor of a console, btw. Don't try to do that with the M68000/Z80 duo of Megadrive development.

• step one: fix the .cmd so they use SFX that suit with the loaded level
• step two: find a way to share revamped SFX through levels
• step three: find a way to hide music loading latencies.

Don't start addressing step three before you get the 'three rooms' demo running and you're ready to encode levels.