4cade/src/glue.prorwts2.a
2020-03-12 12:36:28 -07:00

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;license:MIT
;(c) 2018-2020 by 4am & qkumba
;
; ProRWTS2 glue functions
;
; Public functions
; - LoadFile
; - LoadDHRFile
;
; Public variables
; - gRootDirectory
;
; A general note about paths:
;
; LoadFile, LoadDHRFile, and SaveSmallFile support subdirectories.
; Directories are delimited by '/' like ProDOS. At program startup, we get the
; current directory and save it; that is the PROGRAM ROOT DIRECTORY. All
; pathnames are relative to the PROGRAM ROOT DIRECTORY. There is no concept of
; setting or changing the 'current' directory.
;
; The PROGRAM ROOT DIRECTORY is not guaranteed to be the root directory of the
; underlying ProDOS disk (although it can be). But it doesn't matter, because
; these functions provide no access to any directory above the PROGRAM ROOT
; DIRECTORY. You can't use '..' to access the parent directory, and you can't
; start a pathname with '/' to access the root directory of the underlying
; ProDOS disk.
;
; Examples:
; 'PREFS.CONF' points to a file named 'PREFS.CONF' in the PROGRAM ROOT
; DIRECTORY.
;
; 'FX/RIPPLE' points to a file named 'RIPPLE' in a directory named 'FX' in the
; PROGRAM ROOT DIRECTORY.
;------------------------------------------------------------------------------
; LoadFile
; Load a file into memory all at once, using ProRWTS2
;
; supports paths, see note
;
; in: stack contains 6 bytes of parameters:
; +1 [word] address of length-prefixed pathname
; +3 [word] address of length-prefixed filename
; +5 [word] address to load file, or 0 to use file's default address
; out: all flags clobbered
; all registers clobbered
; gPathname clobbered
;------------------------------------------------------------------------------
LoadFile
+PARAMS_ON_STACK 6
+LDPARAM 1
jsr SetPath
+LDPARAM 3
jsr AddToPath
+LDPARAMPTR 5, ldrlo ; set load address
jsr SwitchToBank2
jsr LoadFileInternal
jmp SwitchToBank1
;------------------------------------------------------------------------------
; LoadAuxFile
; Load a file into aux memory all at once, using ProRWTS2
;
; supports paths, see note
;
; in: stack contains 6 bytes of parameters:
; +1 [word] address of length-prefixed pathname
; +3 [word] address of length-prefixed filename
; +5 [word] address to load file, or 0 to use file's default address
; out: all flags clobbered
; all registers clobbered
; gPathname clobbered
;------------------------------------------------------------------------------
LoadAuxFile
+PARAMS_ON_STACK 6
+LDPARAM 1
jsr SetPath
+LDPARAM 3
jsr AddToPath
+LDPARAMPTR 5, ldrlo ; set load address
jsr SwitchToBank2
lda #1 ; request aux memory
jsr LoadFileAuxInternal
jmp SwitchToBank1
;------------------------------------------------------------------------------
; LoadDHRFile
; load .A2FC file (uncompressed double hi-res graphics) into memory
; all at once, using ProRWTS2
; first $2000 bytes of file are loaded into auxiliary memory $4000..$5FFF
; second $2000 bytes of file are loaded into main memory $4000..$4FFF
;
; supports paths, see note
;
; in: stack contains 4 bytes of parameters:
; +1 [word] address of length-prefixed pathname
; +3 [word] address of length-prefixed filename
; out: all flags clobbered
; all registers clobbered
; stack set to next instruction after parameters
;------------------------------------------------------------------------------
LoadDHRFile
+PARAMS_ON_STACK 4
+LDPARAM 1
jsr SetPath
+LDPARAM 3
jsr AddToPath
jsr SwitchToBank2
jsr LoadDHRFileInternal
jmp SwitchToBank1
gRootDirectory
!word $FDFD