366 lines
8.8 KiB
NASM
Executable File
366 lines
8.8 KiB
NASM
Executable File
; Conway's Game of Life for Apple II
|
|
; Copyright (C) 2016 Christophe Meneboeuf <christophe@xtof.info>
|
|
;
|
|
; This program is free software: you can redistribute it and/or modify
|
|
; it under the terms of the GNU General Public License as published by
|
|
; the Free Software Foundation, either version 3 of the License, or
|
|
; (at your option) any later version.
|
|
;
|
|
; This program is distributed in the hope that it will be useful,
|
|
; but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
; GNU General Public License for more details.
|
|
;
|
|
; You should have received a copy of the GNU General Public License
|
|
; along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
;
|
|
|
|
.include "apple2.inc"
|
|
.include "zeropage.inc"
|
|
|
|
.import pusha
|
|
.import popa
|
|
.import pushax
|
|
.import popax
|
|
|
|
.export _mode_text
|
|
.export _gfx_init
|
|
.export _gfx_fill
|
|
.export _gfx_pixel
|
|
.export _gfx_get_pixel
|
|
.export _gfx_refresh
|
|
|
|
|
|
.define FULLSCREEN #0
|
|
.define SPLIT #1
|
|
.define LOWRES #0
|
|
.define HIRES #1
|
|
.define PAGE_1 #1
|
|
.define PAGE_2 #2
|
|
|
|
.BSS
|
|
Page_Current: .byte 0
|
|
Page_Future: .byte 0
|
|
|
|
.DATA
|
|
;Pages are composed of lines. Here are their 1st pixel adress
|
|
Page1: .word $400, $480, $500, $580, $600, $680, $700, $780, $428, $4A8, $528, $5A8, $628, $6A8, $728, $7A8, $450, $4D0, $550, $5D0, $650, $6D0, $750, $7D0
|
|
Page2: .word $800, $880, $900, $980, $A00, $A80, $B00, $B80, $828, $8A8, $928, $9A8, $A28, $AA8, $B28, $BA8, $850, $8D0, $950, $9D0, $A50, $AD0, $B50, $BD0
|
|
|
|
|
|
.CODE
|
|
|
|
|
|
;will put the adress of the future page into ptr1
|
|
.macro GET_PAGE_FUTURE
|
|
.local get_page_future_page_1, get_page_future_page_2, get_page_future_end
|
|
LDA Page_Current
|
|
CMP PAGE_1
|
|
BEQ get_page_future_page_2
|
|
;storing the low and high bytes of the page address into ptr1
|
|
get_page_future_page_1:
|
|
LDA #<Page1
|
|
STA ptr1
|
|
LDA #>Page1
|
|
STA ptr1+1
|
|
CLC
|
|
BCC get_page_future_end
|
|
get_page_future_page_2:
|
|
LDA #<Page2
|
|
STA ptr1
|
|
LDA #>Page1
|
|
STA ptr1+1
|
|
get_page_future_end:
|
|
.endmacro
|
|
|
|
|
|
|
|
|
|
;**************************
|
|
;void __fastcall__ mode_text( void );
|
|
_mode_text:
|
|
LDA $C054 ;page 1
|
|
LDA $C051 ;text
|
|
RTS
|
|
|
|
|
|
|
|
|
|
;**************************
|
|
;void __fastcall__ gfx_init( uint8_t RES, uint8_t MODE )
|
|
; Switches to the desired res and mode.
|
|
; Always displays page 1
|
|
_gfx_init:
|
|
res: TAX
|
|
LDY #0
|
|
LDA (sp),Y
|
|
CMP LOWRES
|
|
BNE hires
|
|
lores: LDA $C056
|
|
CLC
|
|
BCC mode
|
|
hires: LDA $C057
|
|
mode: CPX FULLSCREEN
|
|
BNE split
|
|
fullscr:LDA $C052
|
|
CLC
|
|
BCC init_end
|
|
split: LDA $C053
|
|
init_end:
|
|
LDA $C054 ;page 1
|
|
LDA $C050 ;graphics
|
|
LDA PAGE_1
|
|
STA Page_Current
|
|
JSR popa ;the parameter on stack
|
|
RTS
|
|
|
|
|
|
|
|
|
|
|
|
;**************************
|
|
;void __fastcall__ gfx_fill( uint8_t color )
|
|
; Fills the screen with the given color
|
|
_gfx_fill:
|
|
; TODO SWITCH PAGES !!
|
|
;saving the context
|
|
;WARNING context us not saved properly: ptr+1 not saved!
|
|
TAX
|
|
LDA tmp1
|
|
JSR pusha
|
|
LDA ptr1
|
|
JSR pusha
|
|
LDA ptr2
|
|
JSR pusha
|
|
TXA
|
|
;duplicate nybble color
|
|
STA tmp1
|
|
ASL A
|
|
ASL A
|
|
ASL A
|
|
ASL A
|
|
ORA tmp1
|
|
STA tmp1
|
|
;select to page to write into
|
|
LDA Page_Current
|
|
CMP PAGE_1
|
|
BNE page_2
|
|
;storing the low and high bytes of the page address into ptr1
|
|
page_1: LDA #<Page1
|
|
STA ptr1
|
|
LDA #>Page1
|
|
STA ptr1+1
|
|
CLC
|
|
BCC fill
|
|
page_2: LDA #<Page2
|
|
STA ptr1
|
|
LDA #>Page1
|
|
STA ptr1+1
|
|
fill:
|
|
;iterating on X: the line number
|
|
for_lines:
|
|
;getting the 16 bit line adress and storing it in ptr2
|
|
TXA
|
|
ASL
|
|
TAY
|
|
LDA (ptr1),Y
|
|
STA ptr2
|
|
INY
|
|
LDA (ptr1),Y
|
|
STA ptr2+1
|
|
;iterating on Y to fill a line
|
|
LDY #0
|
|
fill_line:
|
|
LDA tmp1 ;reload the color
|
|
STA (ptr2),Y ;color the current pixel
|
|
INY ;next pixel
|
|
CPY #40 ;nb pixels per line
|
|
BNE fill_line
|
|
INX
|
|
CPX #20 ;nb lines
|
|
BNE for_lines
|
|
fill_end:
|
|
;displaying the page we filled
|
|
; TODO SWITCH PAGES !!
|
|
;restoring the context
|
|
JSR popa
|
|
STA ptr2
|
|
JSR popa
|
|
STA ptr1
|
|
JSR popa
|
|
STA tmp1
|
|
RTS
|
|
|
|
|
|
;**************************
|
|
;void __fastcall__ gfx_pixel( uint8_t color, uint8_t coord_x, uint8_t coord_y )
|
|
; Draws a pixel at the given coordinates on the Page_Future
|
|
_gfx_pixel:
|
|
;aliases
|
|
coord_y := tmp3
|
|
;saving the context
|
|
PHA
|
|
LDA tmp3
|
|
JSR pusha
|
|
LDA tmp2
|
|
JSR pusha
|
|
LDA tmp1
|
|
JSR pusha
|
|
LDA ptr1
|
|
LDX ptr1+1
|
|
JSR pushax
|
|
LDA ptr2
|
|
LDX ptr2+1
|
|
JSR pushax
|
|
PLA
|
|
|
|
STA coord_y ;coord_y
|
|
; Modify the color depending on the pixel's line parity
|
|
AND #1
|
|
BEQ even
|
|
odd: ; pixel is on an odd line
|
|
LDA #$0F ;To or with the other nybble when writting the pixel
|
|
STA tmp1
|
|
LDY #(1+7) ;there were 7 pushes to save registers
|
|
LDA (sp),Y ;color
|
|
ASL ;shift the color to put it on high nybble
|
|
ASL
|
|
ASL
|
|
ASL
|
|
CLC
|
|
BCC oddeven
|
|
even: ; pixel is on an even line
|
|
LDA #$F0 ;To or with the other nybble when writting the pixel
|
|
STA tmp1
|
|
LDY #(1+7) ;there were 7 pushes to save registers
|
|
LDA (sp),Y ;color
|
|
oddeven:
|
|
STA tmp2
|
|
|
|
; FIXME : switching to Page 2 does not work
|
|
; dont get the future page and work on page 1
|
|
;GET_PAGE_FUTURE
|
|
LDA #<Page1
|
|
STA ptr1
|
|
LDA #>Page1
|
|
STA ptr1+1
|
|
|
|
; get the line adress and store it in ptr2
|
|
LDA coord_y
|
|
LSR
|
|
ASL
|
|
TAY
|
|
LDA (ptr1),Y
|
|
STA ptr2
|
|
INY
|
|
LDA (ptr1),Y
|
|
STA ptr2+1
|
|
|
|
; get coord_x
|
|
LDY #7 ;there were 4 pushes to save registers
|
|
LDA (sp),Y
|
|
; draw
|
|
TAY
|
|
LDA (ptr2),Y ;a color may have been present on the other nybble
|
|
AND tmp1 ;clearing the pixel's nybble
|
|
ORA tmp2 ;adding the color to the pixel's nyyble
|
|
STA (ptr2),Y
|
|
|
|
;restoring the context
|
|
JSR popax
|
|
STA ptr2
|
|
STX ptr2+1
|
|
JSR popax
|
|
STA ptr1
|
|
STX ptr1+1
|
|
JSR popa
|
|
STA tmp1
|
|
JSR popa
|
|
STA tmp2
|
|
JSR popa
|
|
STA tmp3
|
|
JSR popa ;the 2 parameters on stack
|
|
JSR popa
|
|
RTS
|
|
|
|
|
|
;**************************
|
|
;uint8_t __fastcall__ gfx_get_pixel( uint8_t coord_x, uint8_t coord_y )
|
|
; Returns the pixel's color
|
|
_gfx_get_pixel:
|
|
TAX ; coord_y
|
|
|
|
;saving the context
|
|
LDA ptr1
|
|
JSR pusha
|
|
LDA ptr2
|
|
JSR pusha
|
|
|
|
; Page's address to ptr1
|
|
LDA #<Page1
|
|
STA ptr1
|
|
LDA #>Page1
|
|
STA ptr1+1
|
|
; Line's adress to ptr2
|
|
TXA
|
|
LSR
|
|
ASL
|
|
TAY
|
|
LDA (ptr1),Y
|
|
STA ptr2
|
|
INY
|
|
LDA (ptr1),Y
|
|
STA ptr2+1
|
|
; get coord_x
|
|
LDY #2 ;there were 4 pushes to save registers
|
|
LDA (sp),Y
|
|
TAY
|
|
TXA
|
|
AND #1 ; test line parity to read the correct nybble
|
|
BEQ even_2
|
|
odd_2: LDA (ptr2),Y
|
|
LSR ; color is in lo nybble
|
|
LSR
|
|
LSR
|
|
LSR
|
|
CLC
|
|
BCC end_2
|
|
even_2: LDA (ptr2),Y
|
|
AND #$0F ; color is in hi nybble
|
|
end_2: TAX
|
|
|
|
;restoring the context
|
|
JSR popa
|
|
STA ptr2
|
|
JSR popa
|
|
STA ptr1
|
|
JSR popa ;1st parameter
|
|
|
|
; return value
|
|
TXA
|
|
LDX #0
|
|
|
|
RTS
|
|
|
|
|
|
;**************************
|
|
;void __fastcall__ gfx_refresh( void )
|
|
; Updates the screen by displaying the Future Page which becomes Current
|
|
_gfx_refresh:
|
|
LDA Page_Current
|
|
CMP PAGE_1
|
|
BEQ switch_to_page_2
|
|
|
|
switch_to_page_1:
|
|
LDA $C054 ;page 1
|
|
LDA PAGE_1
|
|
CLC
|
|
BCC switch_to_page_end
|
|
switch_to_page_2:
|
|
LDA $C055 ;page 2
|
|
LDA PAGE_2
|
|
|
|
switch_to_page_end:
|
|
STA Page_Current
|
|
RTS
|