dos33fsprogs/gr-sim/gr-sim.c
Vince Weaver a8970f761b tfv: have RLE image loading working
forgot how much I hate 6502 assembler
2017-05-06 19:29:19 -04:00

598 lines
8.2 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <SDL.h>
#include "gr-sim.h"
#include "apple2_font.h"
#define XSIZE 40
#define YSIZE 48
#define PIXEL_X_SCALE 14
#define PIXEL_Y_SCALE 8
static int xsize=XSIZE*PIXEL_X_SCALE;
static int ysize=YSIZE*PIXEL_Y_SCALE;
static int debug=0;
/* 128kB of RAM */
#define RAMSIZE 128*1024
unsigned char ram[RAMSIZE];
/* Registers */
unsigned char a,y,x;
/* Zero page addresses */
#define WNDLFT 0x20
#define WNDWDTH 0x21
#define WNDTOP 0x22
#define WNDBTM 0x23
#define CH 0x24
#define CV 0x25
#define GBASL 0x26
#define GBASH 0x27
#define BASL 0x28
#define BASH 0x29
#define H2 0x2C
#define V2 0x2D
#define MASK 0x2E
#define COLOR 0x30
#define FIRST 0xF0
#define TEMP 0xFA
static SDL_Surface *sdl_screen=NULL;
int grsim_input(void) {
SDL_Event event;
int keypressed;
while ( SDL_PollEvent(&event)) {
switch(event.type) {
case SDL_KEYDOWN:
keypressed=event.key.keysym.sym;
switch (keypressed) {
case SDLK_ESCAPE:
return 'q';
default:
return keypressed;
}
break;
case SDL_JOYBUTTONDOWN:
case SDL_JOYAXISMOTION:
default:
printf("Unknown input action!\n");
break;
}
}
return 0;
}
static unsigned int color[16]={
0, /* 0 black */
0xe31e60, /* 1 magenta */
0x604ebd, /* 2 dark blue */
0xff44fd, /* 3 purple */
0x00a360, /* 4 dark green */
0x9c9c9c, /* 5 grey 1 */
0x14cffd, /* 6 medium blue */
0xd0c3ff, /* 7 light blue */
0x607203, /* 8 brown */
0xff6a3c, /* 9 orange */
0x9d9d9d, /* 10 grey 2 */
0xffa0d0, /* 11 pink */
0x14f53c, /* 12 bright green */
0xd0dd8d, /* 13 yellow */
0x72ffd0, /* 14 aqua */
0xffffff, /* 15 white */
};
/* a = ycoord */
static int gbascalc(unsigned char a) {
unsigned char s,c;
/* input ABCD EFGH */
s=a; /* store a on stack */
c=a&1;
a=a>>1; /* lsr */
a=a&0x3; /* mask */
a=a|0x4; /* 00001FG */
ram[GBASH]=a;
a=s;
a=a&0x18; /* 000D E000 */
/* if odd */
if (c) {
a=a+0x7f+1;
}
ram[GBASL]=a;
a=a<<2;
a=a|ram[GBASL];
ram[GBASL]=a;
if (debug) printf("GBAS=%02X%02X\n",ram[GBASH],ram[GBASL]);
return 0;
}
static short y_indirect(unsigned char base, unsigned char y) {
unsigned short addr;
addr=(((short)(ram[base+1]))<<8) | (short)ram[base];
if (debug) printf("Address=%x\n",addr+y);
return addr+y;
}
int scrn(unsigned char xcoord, unsigned char ycoord) {
unsigned char a,y,c;
a=ycoord;
y=xcoord;
c=a&1;
a=a>>1;
gbascalc(a);
a=ram[y_indirect(GBASL,y)];
if (c) {
return a>>4;
}
else {
return a&0xf;
}
return 0;
}
int grsim_update(void) {
int x,y,i,j;
unsigned int *t_pointer;
t_pointer=((Uint32 *)sdl_screen->pixels);
for(y=0;y<YSIZE;y++) {
for(j=0;j<PIXEL_Y_SCALE;j++) {
for(x=0;x<XSIZE;x++) {
for(i=0;i<PIXEL_X_SCALE;i++) {
*t_pointer=color[scrn(x,y)];
t_pointer++;
}
}
}
}
SDL_UpdateRect(sdl_screen, 0, 0, xsize, ysize);
return 0;
}
int grsim_init(void) {
int mode;
int x;
mode=SDL_SWSURFACE|SDL_HWPALETTE|SDL_HWSURFACE;
if ( SDL_Init(SDL_INIT_VIDEO) < 0 ) {
fprintf(stderr,
"Couldn't initialize SDL: %s\n", SDL_GetError());
return -1;
}
/* Clean up on exit */
atexit(SDL_Quit);
/* assume 32-bit color */
sdl_screen = SDL_SetVideoMode(xsize, ysize, 32, mode);
if ( sdl_screen == NULL ) {
fprintf(stderr, "ERROR! Couldn't set %dx%d video mode: %s\n",
xsize,ysize,SDL_GetError());
return -1;
}
/* Init screen */
for(x=0x400;x<0x800;x++) ram[x]=0;
/* Set up some zero page values */
ram[WNDLFT]=0x00;
ram[WNDWDTH]=0x28;
ram[WNDTOP]=0x00;
ram[WNDBTM]=0x18;
a=0; y=0; x=0;
return 0;
}
int color_equals(int new_color) {
/* Top and Bottom both have color */
ram[COLOR]=((new_color%16)<<4)|(new_color%16);
return 0;
}
static void plot(void) {
unsigned char c;
/* Call into Monitor $F800 */
c=a&1; /* save LSB in carry */
a=a>>1; /* lsr A */
gbascalc(a);
if (c) {
/* If odd, mask is 0xf0 */
ram[MASK]=0xf0;
}
else {
/* If even, mask is 0x0f */
ram[MASK]=0x0f;
}
a=ram[y_indirect(GBASL,y)];
a=a^ram[COLOR];
a=a&ram[MASK];
a=a^ram[y_indirect(GBASL,y)];
ram[y_indirect(GBASL,y)]=a;
}
int basic_plot(unsigned char xcoord, unsigned char ycoord) {
if (ycoord>40) {
printf("Y too big %d\n",ycoord);
return -1;
}
/* Applesoft Source Code */
/* F225 GET X,Y Values */
/* Y-coord in A */
/* X-coord in Y */
/* Check that X-coord<40 */
a=ycoord;
y=xcoord;
if (y>=40) {
printf("X too big %d\n",y);
return -1;
}
plot();
return 0;
}
int basic_hlin(int x1, int x2, int at) {
int i;
for(i=x1;i<x2;i++) basic_plot(i,at);
return 0;
}
static void bascalc(void) {
// FBC1
unsigned char s,c;
s=a;
c=a&0x1;
a=a>>1;
a=a&0x3;
a=a|0x4;
ram[BASH]=a;
a=s;
a=a&0x18;
if (c!=0) {
a=a+0x80;
}
// BSCLC2
ram[BASL]=a;
a=a<<2;
a=a|ram[BASL];
ram[BASL]=a;
}
static void vtabz(void) {
bascalc();
a+=ram[WNDLFT];
ram[BASL]=a;
}
static void vtab(void) {
a=ram[CV];
vtabz();
}
static void setwnd(void) {
ram[WNDTOP]=a;
a=0x0;
ram[WNDLFT]=a;
a=0x28;
ram[WNDWDTH]=a;
a=0x18;
ram[WNDBTM]=a;
a=0x17;
// TABV
ram[CV]=a;
vtab();
}
static void vline(void) {
unsigned char s;
// f828
vline_loop:
s=a;
plot();
a=s;
if (a<ram[V2]) {
a++;
goto vline_loop;
}
}
static void clrtop(void) {
// f836
y=0x27;
ram[V2]=y;
y=0x27;
clrsc3:
a=0x0;
ram[COLOR]=a;
vline();
y--;
if (y>0) goto clrsc3;
}
int gr(void) {
// F390
// LDA SW.LORES
// LDA SW.MIXSET
//JMP MON.SETGR
// FB40
// LDA TXTCLR
// LDA MIXSET
clrtop();
a=0x14;
setwnd();
return 0;
}
int bload(char *filename, int address) {
FILE *fff;
int count=0,ch=0;
fff=fopen(filename,"r");
if (fff==NULL) {
fprintf(stderr,"Could not open %s\n",filename);
return -1;
}
while(1) {
if ((address+count)>RAMSIZE) {
fprintf(stderr,"ERROR ram too high\n");
return -1;
}
ch=fgetc(fff);
if (ch<0) break;
ram[address+count]=ch;
count++;
}
fclose(fff);
return 0;
}
static int cleolz(void) {
// FC9E
a=0xa0;
clreol2:
ram[y_indirect(BASL,y)]=a;
y++;
if (y<ram[WNDWDTH]) goto clreol2;
return 0;
}
static int cleop1(void) {
unsigned char s;
cleop1_begin:
s=a;
vtabz();
cleolz();
y=0x00;
a=s;
a++;
if (a<=ram[WNDBTM]) goto cleop1_begin;
vtab();
return 0;
}
int home(void) {
/* FC58 */
a=ram[WNDTOP];
ram[CV]=a;
y=0x00;
ram[CH]=y;
cleop1();
return 0;
}
int grsim_unrle(unsigned char *rle_data, int address) {
// int xoffset=0;
// int yoffset=0;
unsigned char s;
// int out_pointer;
ram[GBASL]=0; // input address
ram[GBASH]=0;
x=0;
y=0;
ram[BASL]=address&0xff;
ram[BASH]=address>>8;
ram[CV]=0;
ram[CH]=rle_data[y_indirect(GBASL,y)];
y++;
// ysize=rle_data[1];
y++;
while(1) {
a=rle_data[y_indirect(GBASL,y)];
if (a==0xff) break;
ram[TEMP]=a;
y++;
if (y==0) ram[GBASH]++;
a=rle_data[y_indirect(GBASL,y)];
y++;
if (y==0) ram[GBASH]++;
s=y;
y=0;
while(1) {
ram[y_indirect(BASL,y)]=a;
ram[BASL]++;
if (ram[BASL]==0) ram[BASH]++;
x++;
if (x>=ram[CH]) {
if (ram[BASL]>0xa7) ram[BASH]++;
ram[BASL]+=0x58;
ram[CV]+=2;
if (ram[CV]>14) {
ram[CV]=0;
if (ram[BASL]<0xd8) {
ram[BASL]=ram[BASL]-0xd8;
ram[BASH]=ram[BASH]-0x4;
}
else {
ram[BASL]=ram[BASL]-0xd8;
ram[BASH]=ram[BASH]-0x3;
}
}
x=0;
}
ram[TEMP]--;
if (ram[TEMP]==0) break;
}
y=s;
}
return 0;
}
int basic_vlin(int y1, int y2, int at) {
// f244
// LINCOOR
// GET "A,B AT C"
// PUT SMALLER OF (A,B) IN FIRST,
// AND LARGER OF (A,B) IN H2 AND V2.
// RETURN WITH (X) = C-VALUE.
if (y1>y2) { ram[H2]=y1; ram[V2]=y1; ram[FIRST]=y2; }
else { ram[H2]=y2; ram[V2]=y2; ram[FIRST]=y1; }
x=at;
if (x>48) {
fprintf(stderr,"Error! AT too large %d!\n",x);
}
//VLIN JSR LINCOOR
//F244- 8A 2050 TXA X-COORD IN Y-REG
//F245- A8 2060 TAY
//F246- C0 28 2070 CPY #40 X-COORD MUST BE < 40
//F248- B0 BC 2080 BCS GOERR TOO LARGE
//F24A- A5 F0 2090 LDA FIRST TOP END OF LINE IN A-REG
//F24C- 4C 28 F8 2100 JMP MON.VLINE LET MONITOR DRAW LINE
y=x;
if (y>=40) {
fprintf(stderr,"X value to big in vline %d\n",y);
return -1;
}
a=ram[FIRST];
vline();
// for(i=y1;i<y2;i++) basic_plot(at,i);
return 0;
}