2019-09-24 19:50:40 +00:00
|
|
|
;License:MIT
|
|
|
|
|
;(c) 2018-9 by 4am
|
|
|
|
|
;
|
|
|
|
|
; functions for managing which HGR page is showing, and doing things on the other one
|
|
|
|
|
;
|
|
|
|
|
; - GetOffscreenAddress
|
|
|
|
|
; - LoadTitleOffscreen
|
|
|
|
|
; - LoadCoverOffscreen
|
2019-09-26 17:46:13 +00:00
|
|
|
; - LoadHelpOffscreen
|
2019-09-24 19:50:40 +00:00
|
|
|
; - LoadGameTitleOffscreen
|
2019-09-28 12:35:48 +00:00
|
|
|
; - ResyncPage
|
2019-09-24 19:50:40 +00:00
|
|
|
; - ShowOtherPage
|
|
|
|
|
; - ToggleOffscreenPage
|
|
|
|
|
; - ClearOffscreen
|
|
|
|
|
; - ClearHGR1
|
|
|
|
|
;
|
|
|
|
|
; Public variables
|
|
|
|
|
; - OffscreenPage
|
|
|
|
|
;
|
|
|
|
|
|
|
|
|
|
OffscreenPage
|
|
|
|
|
!byte 1 ; 0 = currently showing HGR page 2
|
|
|
|
|
; (so offscreen is page 1 @ $2000)
|
|
|
|
|
; 1 = currently showing HGR page 1
|
|
|
|
|
; (so offscreen is page 2 @ $4000)
|
|
|
|
|
|
|
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
; GetOffscreenAddress
|
|
|
|
|
; get high byte of HGR page that is currently not showing
|
|
|
|
|
;
|
|
|
|
|
; in: none
|
|
|
|
|
; out: A = high byte of offscreen HGR page (#$20 or #$40)
|
|
|
|
|
; preserves X/Y
|
|
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
GetOffscreenAddress
|
|
|
|
|
lda OffscreenPage
|
|
|
|
|
beq +
|
|
|
|
|
lda #$40
|
|
|
|
|
rts
|
|
|
|
|
+ lda #$20
|
|
|
|
|
rts
|
|
|
|
|
|
|
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
; LoadTitleOffscreen
|
|
|
|
|
; load title screen in the HGR page that is currently not showing
|
|
|
|
|
;
|
|
|
|
|
; in: none
|
|
|
|
|
; out: all flags and registers clobbered
|
|
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
LoadTitleOffscreen
|
2019-09-28 12:35:48 +00:00
|
|
|
!if >kTitleFile = >kCoverFile {
|
2019-09-26 03:01:59 +00:00
|
|
|
lda #<kTitleFile
|
|
|
|
|
+HIDE_NEXT_2_BYTES
|
2019-09-28 12:35:48 +00:00
|
|
|
} else {
|
|
|
|
|
+LDADDR kTitleFile
|
|
|
|
|
bne + ; Always branches, because Y is loaded
|
|
|
|
|
; last with the high byte of the address,
|
|
|
|
|
; which is never 0. I miss my 65c02.
|
|
|
|
|
}
|
2019-09-26 17:46:13 +00:00
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
; LoadHelpOffscreen
|
|
|
|
|
; load help screen in the HGR page that is currently not showing
|
|
|
|
|
;
|
|
|
|
|
; in: none
|
|
|
|
|
; out: all flags and registers clobbered
|
|
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
LoadHelpOffscreen
|
|
|
|
|
+LDADDR kHelpFile
|
|
|
|
|
bne LoadOffscreenFromAY ; always branches
|
|
|
|
|
|
2019-09-24 19:50:40 +00:00
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
; LoadCoverOffscreen
|
|
|
|
|
; load cover screen in the HGR page that is currently not showing
|
|
|
|
|
;
|
|
|
|
|
; in: none
|
|
|
|
|
; out: all flags and registers clobbered
|
|
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
LoadCoverOffscreen
|
|
|
|
|
+LDADDR kCoverFile
|
2019-09-26 17:46:13 +00:00
|
|
|
LoadOffscreenFromAY
|
2019-09-24 19:50:40 +00:00
|
|
|
+STAY @fname
|
|
|
|
|
jsr GetOffscreenAddress
|
|
|
|
|
sta +
|
|
|
|
|
jsr LoadFile
|
|
|
|
|
!word kRootDirectory
|
|
|
|
|
@fname !word $FDFD ; SMC
|
|
|
|
|
!byte $00
|
|
|
|
|
+ !byte $FD ; SMC
|
|
|
|
|
rts
|
|
|
|
|
|
|
|
|
|
LoadGameTitleOffscreen
|
|
|
|
|
; in: X = game index
|
|
|
|
|
+LDADDR gGamesListStore
|
|
|
|
|
jsr okvs_nth
|
|
|
|
|
+STAY @fname
|
|
|
|
|
jsr GetOffscreenAddress
|
|
|
|
|
sta +
|
|
|
|
|
jsr LoadFile
|
|
|
|
|
!word kHGRTitleDirectory
|
|
|
|
|
@fname !word $FDFD ; SMC
|
|
|
|
|
!byte $00
|
|
|
|
|
+ !byte $FD ; SMC
|
|
|
|
|
rts
|
|
|
|
|
|
|
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
; ClearOffscreen
|
|
|
|
|
; clear $2000..$3FFF or $4000..$5FFF, depending on which HGR page is not
|
|
|
|
|
; visible right now
|
|
|
|
|
; does not change HGR mode
|
|
|
|
|
;
|
|
|
|
|
; in: none
|
|
|
|
|
; out: $2000..$3FFF or $4000..$5FFF cleared
|
|
|
|
|
; A = 0
|
|
|
|
|
; X = 0
|
|
|
|
|
; Y = 0
|
|
|
|
|
; Z = 1
|
|
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
ClearOffscreen
|
|
|
|
|
jsr GetOffscreenAddress
|
|
|
|
|
+HIDE_NEXT_2_BYTES
|
|
|
|
|
ClearHGR1
|
2019-09-26 03:01:59 +00:00
|
|
|
lda #$20 ; note to self: LDX #$20 can't move here
|
2019-09-24 19:50:40 +00:00
|
|
|
sta @a+2
|
|
|
|
|
ldx #$20
|
|
|
|
|
lda #$80
|
|
|
|
|
ldy #0
|
|
|
|
|
@a sta $2000,y
|
|
|
|
|
iny
|
|
|
|
|
bne @a
|
|
|
|
|
inc @a+2
|
|
|
|
|
dex
|
|
|
|
|
bne @a
|
|
|
|
|
rts
|
|
|
|
|
|
2019-09-28 12:35:48 +00:00
|
|
|
ResyncPage
|
|
|
|
|
jsr ToggleOffscreenPage
|
|
|
|
|
; execution falls through here
|
|
|
|
|
|
2019-09-24 19:50:40 +00:00
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
; ShowOtherPage
|
|
|
|
|
; switch to the HGR page that is not currently showing
|
|
|
|
|
;
|
|
|
|
|
; in: none
|
|
|
|
|
; out: A = new value of OffscreenPage
|
|
|
|
|
; preserves X/Y
|
|
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
ShowOtherPage
|
|
|
|
|
jsr ToggleOffscreenPage
|
|
|
|
|
bne +
|
|
|
|
|
bit PAGE2 ; show page 2
|
|
|
|
|
rts
|
|
|
|
|
+ bit PAGE1 ; show page 1
|
|
|
|
|
rts
|
|
|
|
|
|
|
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
; ToggleOffscreenPage
|
|
|
|
|
; switch the internal variable that tracks which HGR page is showing
|
|
|
|
|
; (does not affect screen)
|
|
|
|
|
;
|
|
|
|
|
; in: none
|
|
|
|
|
; out: A = new value of OffscreenPage
|
|
|
|
|
; preserves X/Y
|
|
|
|
|
;------------------------------------------------------------------------------
|
|
|
|
|
ToggleOffscreenPage
|
|
|
|
|
lda OffscreenPage
|
|
|
|
|
eor #$01
|
|
|
|
|
sta OffscreenPage
|
|
|
|
|
rts
|
