The disk is in the Jim Peterson Tigercub public domain disk collection, readily available. (I sent the disk to Jim and the incomplete readme file is by me). This note 2020.
The source code for JBM103 is in the French TI Magazine- 99 Magazine - issue 11 of the magazine, undated, with some details of the CALL LINKs. (http://gilles.susini.free.fr/magazines.html)
The article is by Alexandre Mortilla, who I will now consider to be the author of JBM103.
It is possible the work was inspired by earlier articles on bit map graphics by Jean Marin. I suspect the anonymous disk I received in the post was from the collection of Jean-Bernard Morelle, whence the jbm.
I could not see an explanation of the essential CALL LOADS that the XB program needs to start with, and which sometimes have different second values passed (I have seen 0, 2, and 24).
"Tout programe graphique doit demarrer par la lignesuivante: 10 CALL LOAD(-31890,56,24) :: CALL LOAD(-31964,56,24)" [BUT the demo program included instead uses (-31890,56,2) !]
"On est en CALL FILES(1), soit un seul fichier ouvert a la foir."
"Interdiction d'utiliser la directive d'asseblage DEF "
BREAK a running program press "simultanement sur FCTN puis 5 puis 4" (FCTN 5 switches to 24x32 then FCTN 4 will break.
Once the SCRO is loaded you can switch between modes with FCTN 5 SCR1) and FCTN 6 (SCR2).The article suggests using CALL FILES(1).
The LINKS available: eg CALL LINK("SCR2")
SCR2 switches to bit map mode
SCR1 switches to 24x32 mode
CLEAR clears screen
SAUVE saves image ("SAUVE","DSK1.PIC_P")
CHARGE loads old image ("CHARGE","DSK1.PIC_P)
-the underline P provides compatability with TI Artist pictures and is
otherwise not required.
("POINT", color, y,x)
[The video chip does not permit three colours in a line of 8 pixels, which can restrict the use of the color settings but should not result in an error- just a messy picture].
("CERCLE", color, y centre, x centre, radius)
("LIGNE", COLOR, Y, X [,Y2,X2] )
"Si Y2 et X2 ne sont pas fournis, la ligne tracee demarre de la fin de la ligne precedente jusqu'a Y,Y, ou bien de l'origine fixeee par "ORIGIN" jusqu'a Y,X
("ORIGIN",Y,X) sets first point (see LIGNE)