;-------------------------gmessout routine begins--------------------------+
; NAME  GMESSOUT
;
; from BLUEBOOK OF ASSEMBLY ROUTINES FOR IBM PC & XT.
;         page : 154

; ROUTINE FOR PRINTING A STRING ON THE GRAPHICS SCREEN
;
; FUNCTION: This routine prints a messgae on the graphics screen, using
; the SCHAR or RCHAR routines.  The message terminates in a zero.
;
; INPUT: Upon entry:
;
; 	address of message is in SI
;	x-coord of upper LH corner is in xmess
;	y-coord of upper LH corner is in ymess
;	horiz magnitude of characters is in xmagn
;	vert magnitude of characters is in xmagn
;	color of chars is in color
;	choice of fonts (0=stroke, 1=raster) is in font
;
; OUTPUT: Just to the screen
;
; REGISTERS USED:  None modified
;
; SEGMENTS REFERENCED:  Upon entry ES must point to the video RAM at
; 0B8000h and DS must point to the data segment used by the point-plot,
; box-filling, line-drawing and stroke character routines.
;
; ROUTINES CALLED:  SCHAR or RCHAR
;
; SPECIAL NOTES: No bounds ;hecking is performed.  Unpredictable results
; will occur if the horizontal or vertical magnitude is too large.
;
; ROUTINE TO PRINT A MESSAGE TO THE GRAPHICS SCREEN
;
gmessout	proc	far
;
; get (x,y) location of message on screen
	mov	ax,xmess	; get x-coord on screen
	mov	x0,ax		; for first char
	mov	ax,ymess	; get y-coord on screen
	mov	y0,ax		; for first char
	cld			; forward direction
;
; main loop through characters of the message
gmessloop:
	cld			; forward direction
	lodsb			; get the ASCII code
	cmp	al,0		; test for end of string
	je	gmessexit
;
; check for fonts
font0:
	cmp	font,0		; use font 0 ?
	jne	nextchar
	call	rchar		; plot raster characters
;
nextchar:
	mov	al,8		; char cell width
	mov	cl,xmagn	; times horizontal magnitude
	mul	cl		; multiply
	add	x0,ax		; add to location of previous char
;
	jmp	gmessloop	; loop for next char
;
gmessexit:
	ret			; return
;
gmessout	endp
;-------------------------gmessout routine ends---------------------------+