SID SOUND DESIGNER

- part two : ze come back -



By The Beast



Following the article of FroST in the last Toxic Mag, I wondered if it was possible to adapt the routine to play the musics the type " Sid Sound Designer " in GFA Basic. I am myself risky to convert the source provided with the Toxic Mag 17 in GFA, but in vain. But it was without counting on the Zorro of the modern times, the one that comes to save the widow and him in time orphan, I named: ST GHOST! Indeed, the B timer is already used by the GFA, he was therefore impossible to replay some musics " Sid Sound " as. ST Ghost was therefore in charge of modifying the player so that it uses the timer C. Exyl passed by there and he concocted a small player for fans of the GFA that only waited for that!


Why is he/it preferable to include a music to the format " Sid Sound Designer " in a demo? Because that changes the old musics to Mad Max, Big Alec or Count Zero and because I remain convinced that the design is something of very important in a demo, it is in my opinion more important than the technical level of the programming. ST Survivor had written an article about the design in an old Toxic Mag, the 16 he seems to me, he would be good that programmers of demos himself refers there from time to time. One yet sees too many demos very good, technically talking, but without no design. What a waste!


Go, truce of craptalking, one spends to the printout, that is very short. You will find the GFA source somewhere in the Toxic 18.


     . Routine SID pour le GFA
     . Code : ST Ghost & Exyl  SECTOR ONE
     .
     CLS
     RESERVE 50000
     .
     INLINE sid_gfa%,244
     INLINE sid_rout%,9014


*** WARNING ***
These two INLINES contain the player in assembler. He/it is very important, or even IMPERATIVE, to reload them rightly before executing the program, under pain of bombing ! For beginners, it is necessary to protect these INLINES: put the cursor over, press HELP then SAVE. I noticed that to the least modification of the source, the fact not to reload the INLINES can drive to nice bombs !


     INLINE tri%,16260
     INLINE tvs%,17172


Every music " Sid Sound " is composed of two files: the one whose extension is TRI contains the partition, and the one whose extension is TVS contains instruments. You are not obliged to put files in the INLINES, he/it is possible to load them with FILESELECT then BGET, for example.


     super%=GEMDOS(32,L:0)  ! superviseur
     .
     ~C:sid_gfa%(L:tvs%,L:tri%,L:sid_rout%,W:50,W:0)


The player is called while passing parameters. " tvs%" and "tri% are " addresses of files * .TVS and * .TRI, we saw them higher. 50 is the frequency of the screen (50 Hz), it will be necessary to change this parameter consequently, to the risk to play music more quickly than she should be he. As for the last parameter, he/it simply indicates that it is necessary to play music.


     ~GEMDOS(32,L:super%)   ! on retourne au mode utilisateur
     .
     ~INP(2)   ! attente de touche
     .
     super%=GEMDOS(32,L:0)  ! superviseur
     .
     ~C:sid_gfa%(L:0,L:0,L:sid_rout%,W:0,W:-1)


To stop music, it is not necessary to take care that of the 3rd and the 5th parameter. Them others can be let to 0. The last parameter must contain the value -1 in order to signal to the player whom one wants to cut music.


     ~GEMDOS(32,L:super%)   ! on retourne au mode utilisateur
     .
     RESERVE
     EDIT


And it's OK. I hope that this small routine will be you very useful for your next realizations. As for the files TRI and TVS, to part on Internet, I don't see too much where you will be able to find some. If you don't have access to the network of networks, you can send me a disk + a stamped envelope and drawn to your name and address (mine is in the editorial).



Greetings to ST GHOST and EXYL for the diffusion of the source -




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