prog8/examples/cx16/zsound/play-zsound.p8

%import textio
%import cx16diskio
%import palette
%zeropage basicsafe
%zpreserved $22,$2d     ; zsound lib uses this region


;; Proof Of Concept Zsound player using a binary blob version of zsound library by ZeroByte relocated to something usable here.
;; Can play ZSM (music) and ZCM (pcm samples).

; "issues":
; - prog8 (or rather, 64tass) cannot "link" other assembly object files so we have to incbin a binary blob.
; - zsound player ZP usage is only known after compilation of zsound lib. And then this has to be blocked off in the prog8 program.
; - zsound lib BSS section has to be expanded into real zeros as part of the included binary.
; - zsound binary starts with 2 byte prg header that shifts the jump table 2 bytes (not a big issue but a bit untidy)
; - prog8 always sticks main module at the beginning so can't create a container module to stick zsound in (if you want to load it at the beginning)
; - prog8 always has some bootstrap code after the basic launcher so we can only start loading stuff after that
; - prog8 main has to be set to a fixed address (in this case $0830) to which the special zsound binary has been compiled as well.


main $0830 {

zsound_lib:
    ; this has to be the first statement to make sure it loads at the specified module address $0830
    %asmbinary "zsound_combo-0830.bin"

    ; note: jump table is offset by 2 from the load address (because of prg header)
    romsub $0832 = zsm_init() clobbers(A)
    romsub $0835 = zsm_play() clobbers(A, X, Y)
    romsub $0838 = zsm_playIRQ() clobbers(A, X, Y)
    romsub $083b = zsm_start(ubyte bank @A, uword song_address @XY) clobbers(A, X, Y) -> ubyte @Pc
    romsub $083e = zsm_stop()
    romsub $0841 = zsm_setspeed(uword hz @XY) clobbers(A, X, Y)
    romsub $0844 = zsm_setloop(ubyte count @A)
    romsub $0847 = zsm_forceloop(ubyte count @A)
    romsub $084a = zsm_noloop()
    romsub $084d = zsm_setcallback(uword address @XY)
    romsub $0850 = zsm_clearcallback() clobbers(A)
    romsub $0853 = zsm_get_music_speed() clobbers(A) -> uword @XY
    romsub $0856 = pcm_init() clobbers(A)
    romsub $0859 = pcm_trigger_digi(ubyte bank @A, uword song_address @XY)
    romsub $085c = pcm_play() clobbers(A, X, Y)
    romsub $085f = pcm_stop() clobbers(A)
    romsub $0862 = pcm_set_volume(ubyte volume @A)

    const ubyte song_bank = 1
    const uword song_address = $a000
    const ubyte digi_bank = 6
    const uword digi_address = $a000
    const ubyte zcm_DIGITAB_size = 8        ; header size

    sub start() {
        txt.print("zsound demo program!\n")

        cbm.SETMSG(%10000000)       ; enable kernal status messages for load
        if not cx16diskio.load_raw(8, "colony.zsm", song_bank, song_address) {
            txt.print("?can't load\n")
            return
        }
        if not cx16diskio.load_raw(8, "terminator2.zcm", digi_bank, digi_address) {
            txt.print("?can't load\n")
            return
        } else {
            ; initialize header pointer of the zcm to point to actual sample data
            ; this will be set correcly by zsound lib itself if left at zero
            ; poke(digi_address+2, digi_bank)
            ; pokew(digi_address, digi_address+zcm_DIGITAB_size)
        }
        cbm.SETMSG(0)
        txt.nl()
        cx16.rambank(song_bank)

        play_music()
    }

    sub play_music() {
        zsm_init()
        pcm_init()
        zsm_setcallback(&end_of_song_cb)
        if zsm_start(song_bank, song_address)==0 {
            txt.print("\nmusic speed: ")
            txt.print_uw(zsm_get_music_speed())
            txt.print(" hz\nplaying song! hit enter to also play a digi sample!\n")

            repeat {
                if cx16.joystick_get2(0)!=$ffff
                    pcm_trigger_digi(digi_bank, digi_address)

                sys.waitvsync()
                repeat 1400 {
                    ; artificially delay calling the play routine so we can see its raster time
                    %asm {{
                        nop
                    }}
                }
                palette.set_color(0, $84c)
                pcm_play()
                palette.set_color(0, $f25)
                zsm_play()
                palette.set_color(0, $000)
            }
            zsm_stop()
            pcm_stop()
        } else {
            txt.print("?song start error\n")
        }
    }

    sub end_of_song_cb() {
        txt.print("end of song!\n")
    }
}