working on demo stuff
This commit is contained in:
Vince Weaver
parent
a2155f7255
commit
c8f1fddb76
|
|
@ -0,0 +1,30 @@
|
|||
CC = gcc
|
||||
CFLAGS = -O2 -Wall -I.. -g
|
||||
|
||||
SDL_LIBS= `sdl-config --libs`
|
||||
SDL_INCLUDE= `sdl-config --cflags`
|
||||
GR_SIM = ../gr-sim.a
|
||||
|
||||
all: hellmood_memories hellmood_gr hellmood_simple
|
||||
|
||||
hellmood_memories: hellmood_memories.o
|
||||
$(CC) -o hellmood_memories hellmood_memories.o $(LFLAGS) $(SDL_LIBS)
|
||||
|
||||
hellmood_memories.o: hellmood_memories.c
|
||||
$(CC) $(CFLAGS) $(SDL_INCLUDE) -c hellmood_memories.c
|
||||
|
||||
hellmood_simple: hellmood_simple.o
|
||||
$(CC) -o hellmood_simple hellmood_simple.o $(LFLAGS) $(SDL_LIBS)
|
||||
|
||||
hellmood_simple.o: hellmood_simple.c
|
||||
$(CC) $(CFLAGS) $(SDL_INCLUDE) -c hellmood_simple.c
|
||||
|
||||
|
||||
hellmood_gr: hellmood_gr.o
|
||||
$(CC) $(LFLAGS) -o hellmood_gr hellmood_gr.o $(GR_SIM) $(SDL_LIBS)
|
||||
|
||||
hellmood_gr.o: hellmood_gr.c
|
||||
$(CC) $(CFLAGS) -c hellmood_gr.c
|
||||
|
||||
clean:
|
||||
rm -f *~ *.o hellmood_memories hellmood_gr hellmood_simple
|
||||
|
|
@ -0,0 +1,637 @@
|
|||
#include <stdio.h>
|
||||
#include <unistd.h>
|
||||
|
||||
#include "gr-sim.h"
|
||||
|
||||
#if 0
|
||||
static unsigned short stack[128];
|
||||
static unsigned short ax,bx,cx,dx,di,bp,es;
|
||||
static int cf=0,of=0,zf=0,sf=0;
|
||||
static int sp=0;
|
||||
static unsigned char framebuffer[320*200];
|
||||
|
||||
static SDL_Surface *sdl_screen=NULL;
|
||||
|
||||
struct palette {
|
||||
unsigned char red[256];
|
||||
unsigned char green[256];
|
||||
unsigned char blue[256];
|
||||
};
|
||||
|
||||
static struct palette pal;
|
||||
|
||||
static int mode13h_graphics_init(void) {
|
||||
|
||||
int mode;
|
||||
|
||||
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(320, 200, 32, mode);
|
||||
|
||||
if ( sdl_screen == NULL ) {
|
||||
fprintf(stderr, "ERROR! Couldn't set 320x200 video mode: %s\n",
|
||||
SDL_GetError());
|
||||
return -1;
|
||||
}
|
||||
SDL_EnableKeyRepeat(SDL_DEFAULT_REPEAT_DELAY, SDL_DEFAULT_REPEAT_INTERVAL);
|
||||
|
||||
SDL_WM_SetCaption("memories -- Linux/C/SDL","memories");
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int mode13h_graphics_update(unsigned char *buffer, struct palette *pal) {
|
||||
|
||||
unsigned int *t_pointer;
|
||||
|
||||
int x,temp;
|
||||
|
||||
/* point to SDL output pixels */
|
||||
t_pointer=((Uint32 *)sdl_screen->pixels);
|
||||
|
||||
for(x=0;x<320*200;x++) {
|
||||
|
||||
temp=(pal->red[buffer[x]]<<16)|
|
||||
(pal->green[buffer[x]]<<8)|
|
||||
(pal->blue[buffer[x]]<<0)|0;
|
||||
|
||||
t_pointer[x]=temp;
|
||||
}
|
||||
|
||||
SDL_UpdateRect(sdl_screen, 0, 0, 320, 200);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int graphics_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 27;
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
return 0;
|
||||
|
||||
}
|
||||
|
||||
|
||||
static void write_framebuffer(int address, int value) {
|
||||
int real_addr;
|
||||
|
||||
real_addr=address-0xa0000;
|
||||
if ((real_addr<0) || (real_addr>320*200)) return;
|
||||
|
||||
framebuffer[real_addr]=value;
|
||||
|
||||
}
|
||||
|
||||
/* unsigned multiply */
|
||||
static void mul_16(unsigned short value) {
|
||||
unsigned int result;
|
||||
|
||||
result=ax*value;
|
||||
|
||||
// printf("%x*%x=%x ",value,ax,result);
|
||||
|
||||
ax=result&0xffff;
|
||||
dx=result>>16;
|
||||
|
||||
// printf("%x:%x x=%d y=%d\n",dx,ax,
|
||||
// dx&0xff,(dx>>8)&0xff);
|
||||
|
||||
|
||||
|
||||
|
||||
if (dx==0) {
|
||||
of=0;
|
||||
cf=0;
|
||||
}
|
||||
else {
|
||||
of=1;
|
||||
cf=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
static void imul(short value) {
|
||||
int result;
|
||||
|
||||
result=ax*value;
|
||||
|
||||
ax=result&0xffff;
|
||||
dx=result>>16;
|
||||
|
||||
}
|
||||
*/
|
||||
|
||||
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_8(char value) {
|
||||
|
||||
short result;
|
||||
char src;
|
||||
|
||||
src=ax;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
ax=result;
|
||||
|
||||
if (ax==(ax&0xff)) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_16(short value) {
|
||||
|
||||
int result;
|
||||
short src;
|
||||
|
||||
src=ax;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
ax=(result&0xffff);
|
||||
dx=((result>>16)&0xffff);
|
||||
|
||||
if (dx==0) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_16_bx(short value) {
|
||||
|
||||
int result;
|
||||
short src;
|
||||
|
||||
src=bx;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
bx=(result&0xffff);
|
||||
|
||||
if (bx==result) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_16_dx(short value) {
|
||||
|
||||
int result;
|
||||
short src;
|
||||
|
||||
src=dx;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
dx=(result&0xffff);
|
||||
|
||||
if (dx==result) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
/* unsigned divide */
|
||||
static void div_8(unsigned char value) {
|
||||
|
||||
unsigned char r,q;
|
||||
unsigned int result,remainder;
|
||||
|
||||
// printf("Dividing %d (%x) by %d (%x): ",ax,ax,value,value);
|
||||
|
||||
if (value==0) {
|
||||
printf("Divide by zero!\n");
|
||||
return;
|
||||
}
|
||||
|
||||
result=ax/value;
|
||||
remainder=ax%value;
|
||||
|
||||
q=result;
|
||||
r=remainder;
|
||||
|
||||
// printf("Result: q=%d r=%d\n",q,r);
|
||||
|
||||
ax=(r<<8)|(q&0xff);
|
||||
|
||||
}
|
||||
|
||||
|
||||
|
||||
static void push(int value) {
|
||||
//printf("Pushing %x\n",value);
|
||||
stack[sp]=value;
|
||||
sp++;
|
||||
}
|
||||
|
||||
static short pop(void) {
|
||||
if (sp==0) {
|
||||
printf("Stack underflow!\n");
|
||||
return 0;
|
||||
}
|
||||
|
||||
sp--;
|
||||
|
||||
//printf("Popping %x\n",stack[sp]);
|
||||
|
||||
return stack[sp];
|
||||
|
||||
}
|
||||
#endif
|
||||
/* tilted plane */
|
||||
/* DH=Y, DL=X */
|
||||
static void fx0(void) {
|
||||
}
|
||||
#if 0
|
||||
char ah,al,dh,dl;
|
||||
unsigned short temp;
|
||||
|
||||
ax=0x1329; // mov ax,0x1329 init
|
||||
|
||||
al=ax&0xff; ah=(ax>>8)&0xff;
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
|
||||
dh=dh+al; // add dh,al ; prevent divide overflow
|
||||
div_8(dh); // div dh ; reverse divide AL=C/Y'
|
||||
|
||||
dx=((dh&0xff)<<8)|dl;
|
||||
|
||||
temp=ax;
|
||||
ax=dx; dx=temp; // xchg dx,ax ; DL=C/Y' AL=X
|
||||
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
imul_8(dl); // imul dl
|
||||
dx=dx-bp; // sub dx,bp
|
||||
dl=dx&0xff;
|
||||
|
||||
ah=(ax>>8)&0xff;
|
||||
ah=ah^dl; // xor ah,dl
|
||||
al=ah; // mov al,ah
|
||||
ax=((ah&0xff)<<8)|(al&0xff);
|
||||
|
||||
ax&=0xff1c; // and al,4+8+16
|
||||
}
|
||||
|
||||
#endif
|
||||
|
||||
/* circles? */
|
||||
/* DH=Y, DL=X */
|
||||
static void fx1(void) {
|
||||
}
|
||||
#if 0
|
||||
int temp;
|
||||
char al,dh,ah;
|
||||
|
||||
// mov al,dh ; get Y in AL
|
||||
al=(dx>>8)&0xff;
|
||||
// sub al,100 ; align Y vertically
|
||||
al=al-100;
|
||||
ax=ax&0xff00;
|
||||
ax=ax|al;
|
||||
// imul al ; AL=Y*Y
|
||||
imul_8(al);
|
||||
// xchg dx,ax ; Y*Y/256 in DH, X in AL
|
||||
temp=ax;
|
||||
ax=dx;
|
||||
dx=temp;
|
||||
// imul al ; AL=X*X
|
||||
imul_8(ax&0xff);
|
||||
// add dh,ah ; DH=X*X+Y*Y/256
|
||||
dh=(dx>>8)&0xff;
|
||||
ah=(ax>>8)&0xff;
|
||||
dh=dh+ah;
|
||||
// mov al,dh ; AL = X*X+Y*Y/256
|
||||
al=dh;
|
||||
|
||||
dx=dx&0xff;
|
||||
dx|=(dh<<8);
|
||||
ax=(ah<<8)|(al&0xff);
|
||||
|
||||
// add ax,bp ; offset color by time
|
||||
ax=ax+bp;
|
||||
// and al,8+16 ; select special rings
|
||||
ax=ax&0xff18;
|
||||
}
|
||||
#endif
|
||||
/* checkers */
|
||||
static void fx2(void) {
|
||||
}
|
||||
#if 0
|
||||
int temp;
|
||||
unsigned char al;
|
||||
|
||||
temp=ax;
|
||||
ax=dx; dx=temp; // xchg dx,ax
|
||||
ax=ax-bp; // sub ax,bp
|
||||
temp=((ax>>8)&0xff)^(ax&0xff);
|
||||
ax=ax&0xff00;
|
||||
ax|=temp; // xor al,ah
|
||||
ax|=0xdb; // or al,0xdb
|
||||
al=ax&0xff;
|
||||
al=al+0x13;
|
||||
ax=ax&0xff00;
|
||||
ax=ax|al; // add al,13h
|
||||
// ret
|
||||
|
||||
}
|
||||
|
||||
#endif
|
||||
/* parallax checkrboard */
|
||||
static void fx3(void) {
|
||||
}
|
||||
|
||||
#if 0
|
||||
cx=bp; // mov cx,bp ; set init point to time
|
||||
bx=-16; // mov bx,-16 ; limit to 16 iterations
|
||||
fx3L:
|
||||
cx=cx+di; // add cx, di ; offset by screenpointer
|
||||
ax=819; // mov ax,819 ; magic, related to Rrrola
|
||||
imul_16(cx); // imul cx ; get X',Y' in DX
|
||||
cf=dx&1; // ror dx,1 ; set carry flag on "hit"
|
||||
dx=dx>>1;
|
||||
if (cf) {
|
||||
dx|=0x8000;
|
||||
}
|
||||
else {
|
||||
dx&=0x7fff;
|
||||
}
|
||||
|
||||
bx++; // inc bx ; increment iteration count
|
||||
if (bx==0) zf=1;// does not affect carry flag
|
||||
else zf=0;
|
||||
// ja fx3L ; loop until "hit" or "iter=max"
|
||||
// jump above, if cf==0 and zf==0
|
||||
if ((cf==0) && (zf==0)) goto fx3L;
|
||||
|
||||
ax=bx+31; // lea ax,[bx+32] ; map value to standard gray scale
|
||||
//printf("%d %d\n",ax,bx);
|
||||
}
|
||||
|
||||
#endif
|
||||
/* sierpinski rotozoomer */
|
||||
static void fx4(void) {
|
||||
}
|
||||
#if 0
|
||||
unsigned char dl,dh,bh,al;
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
cx=bp-2048; // lea cx,[bp-2048] ; center time to pass zero
|
||||
cx=cx<<3; // sal cx,3 ; speed up by factor of 8!
|
||||
ax=(dh&0xff); // movzx ax,dh ; get X into AL
|
||||
// movsx dx,dl ; get Y into DL
|
||||
if (dl&0x80) {
|
||||
dx|=0xff00;
|
||||
}
|
||||
else {
|
||||
dx&=0x00ff;
|
||||
}
|
||||
|
||||
bx=ax; // mov bx,ax ; save X in BX
|
||||
imul_16_bx(cx); // imul bx,cx ; BX=X*T
|
||||
|
||||
/* bl=bx&0xff; */ bh=(bx>>8)&0xff;
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
bh=bh+dl; // add bh,dl ; bh=x*t/256+Y
|
||||
|
||||
imul_16_dx(cx); // imul dx,cx ; dx=Y*T
|
||||
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
// sub al,dh ; al=X-Y*T/256
|
||||
al=ax&0xff; // ah=(ax>>8)&0xff;
|
||||
al=al-dh;
|
||||
|
||||
// and al,bh ; AL=(X-Y*T/256)&(x*T/256+Y)
|
||||
al=al&bh;
|
||||
al=al&252; // and al,252 ; thicker sierpinksi
|
||||
if (al==0) zf=1;
|
||||
else zf=0;
|
||||
cf=0; of=0;
|
||||
// salc ; set pixel value to black
|
||||
if (cf==0) al=0;
|
||||
else al=0xff;
|
||||
|
||||
/* NOTE: remove the line below and the background becomes a rainbow */
|
||||
ax=al;
|
||||
// jnz fx4q ; leave black if not sierpinksi
|
||||
if (zf==0) goto fx4q;
|
||||
|
||||
ax=ax&0xff00; // mov al,0x2a ; otherwise: a nice orange
|
||||
ax|=0x2a;
|
||||
fx4q:
|
||||
;
|
||||
}
|
||||
|
||||
#endif
|
||||
/* raycast bent tunnel */
|
||||
static void fx5(void) {
|
||||
|
||||
#if 0
|
||||
unsigned char al,cl;
|
||||
unsigned short temp;
|
||||
|
||||
cx=cx&0xff00;
|
||||
cx|=(-9&0xff); // mov cl,-9 ; start with depth 9 (moves backwards)
|
||||
fx5L:
|
||||
cl=cx&0xff;
|
||||
|
||||
push(dx); // push dx ; save DX, destroyed inside loop
|
||||
al=(dx>>8)&0xff;// mov al,dh ; get Y into AL
|
||||
al-=100; // sub al,100 ; centering Y manually
|
||||
|
||||
ax=ax&0xff00;
|
||||
ax|=(al&0xff);
|
||||
|
||||
imul_8(cl); // imul cl ; multiply AL=Y by current distance to get projection
|
||||
// xchg ax,dx ; gt X into AL while saving DX
|
||||
temp=ax;
|
||||
ax=dx;
|
||||
dx=temp;
|
||||
|
||||
al=ax&0xff;
|
||||
al+=cl; // add al,cl ; add distance to projection (bend right)
|
||||
|
||||
ax=ax&0xff00;
|
||||
ax|=(al&0xff);
|
||||
imul_8(cl); // imul cl ; multiply AL=X by the current projection
|
||||
al=(dx>>8)&0xff;// mov al,dh ; get projection(1) in AL
|
||||
al^=(ax>>8); // xor al,ah ; combine with projection(2)
|
||||
al+=4; // add al,4 ; center the walls around 0
|
||||
if (al&-8) { // test al,-8 ; test if the wall is hit
|
||||
zf=0;
|
||||
}
|
||||
else {
|
||||
zf=1;
|
||||
}
|
||||
|
||||
dx=pop(); // pop dx (restore dx)
|
||||
cx&=0xff00;
|
||||
cx|=(cl&0xff);
|
||||
cx--;
|
||||
if ((cx!=0) && (zf==1)) goto fx5L;
|
||||
// loopz fx5L (repeat until "hit" or "iter=max"
|
||||
|
||||
cx=cx-bp; // sub cx,bp ; offset depth by time
|
||||
al^=(cx&0xff); // xor al,cl ; XOR pattern for texture
|
||||
// ah=al/6;
|
||||
al=al%6; // aam 6 ; irregular pattern with MOD 6
|
||||
al+=20; // add al,20 ; offset into grayscale pattern
|
||||
ax=al&0xff;
|
||||
#endif
|
||||
}
|
||||
|
||||
|
||||
/* ocean night */
|
||||
static void fx6(void) {
|
||||
}
|
||||
#if 0
|
||||
char dh;
|
||||
double f;
|
||||
int edx;
|
||||
char scratch[64];
|
||||
|
||||
// bx coming in is the address of the effect
|
||||
// this is a guess, too lazy to hexdump
|
||||
bx=0x1d5;
|
||||
|
||||
// si=?? based on sound playing?
|
||||
// ax (sky color) is ?
|
||||
|
||||
dh=dx>>8;
|
||||
// sub dh,120 ; check if pixel in the sky
|
||||
dh=dh-120;
|
||||
sf=!!(dh&0x80);
|
||||
// js fx6q ; quit if that's the case
|
||||
if (sf) goto fx6q;
|
||||
|
||||
dx&=0xff;
|
||||
dx|=dh<<8;
|
||||
|
||||
// mov [bx+si],dx ; move xy to memory location
|
||||
// fild word [bx+si] ; read as integer
|
||||
// fidivr dword [bx+si] ; reverse divide by constant
|
||||
// Divide m32int by ST(0) and store result in ST(0)
|
||||
// fstp dword [bx+si-1] ; store result as floating point
|
||||
// mov ax,[bx+si] ; get result into ax
|
||||
|
||||
memcpy(&scratch[32],&dx,sizeof(short));
|
||||
f=dx;
|
||||
memcpy(&edx,&scratch[32],sizeof(int));
|
||||
f=f/edx;
|
||||
memcpy(&scratch[31],&f,sizeof(double));
|
||||
memcpy(&ax,&scratch[32],sizeof(short));
|
||||
|
||||
|
||||
|
||||
|
||||
ax+=bp; // add ax,bp ; modify color by time
|
||||
ax&=0xff80; // and al,128 ; threshold into two bands
|
||||
ax--; // dec ax ; beautify colors to blue/black
|
||||
fx6q: ;
|
||||
}
|
||||
#endif
|
||||
|
||||
int main(int argc, char **argv) {
|
||||
|
||||
int which=5,ch;
|
||||
|
||||
grsim_init();
|
||||
|
||||
gr();
|
||||
|
||||
clear_screens();
|
||||
|
||||
while(1) {
|
||||
|
||||
switch (which) {
|
||||
case 0: fx2(); break;
|
||||
case 1: fx1(); break;
|
||||
case 2: fx0(); break;
|
||||
case 3: fx3(); break;
|
||||
case 4: fx4(); break;
|
||||
case 5: fx5(); break;
|
||||
case 6: fx6(); break;
|
||||
case 7: goto end;
|
||||
default: printf("Trying effect %d\n",which);
|
||||
}
|
||||
|
||||
grsim_update();
|
||||
|
||||
ch=grsim_input();
|
||||
if (ch=='q') goto end;
|
||||
|
||||
usleep(10000);
|
||||
|
||||
|
||||
}
|
||||
|
||||
end:
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
|
@ -0,0 +1,763 @@
|
|||
/* A Linux/SDL/C version of Hellmood's amazing 256B DOS Memories Demo */
|
||||
|
||||
/* See http://www.sizecoding.org/wiki/Memories for a rundown on how it works */
|
||||
|
||||
/* This is a conversion to C I did in an attempt to see how it works */
|
||||
/* and also to see if I could port any of this to the Apple II */
|
||||
|
||||
/* x86 has amazing code density with powerful instructions */
|
||||
/* stos, mul, div, FPU, lots of 1-byte instructions */
|
||||
/* and old x86 hardware made it really easy to program with limited code */
|
||||
/* VGA/MCGA Mode13h (320x200 256 colors linear framebuffer) */
|
||||
/* soundblaster MIDI with only a few out instructions */
|
||||
|
||||
/* Anyway this is a rough attempt to getting things going in C */
|
||||
/* The last effect (ocean) is doing lots of sketchy stuff and */
|
||||
/* depending a bit on undefined behavior so it's hit or miss */
|
||||
/* whether it will work for you */
|
||||
|
||||
/* deater -- Vince Weaver -- vince@deater.net -- 23 April 2020 */
|
||||
|
||||
#include <stdio.h>
|
||||
#include <unistd.h>
|
||||
|
||||
#include <SDL.h>
|
||||
|
||||
static unsigned short stack[128];
|
||||
static unsigned short ax,bx,cx,dx,di,bp,es;
|
||||
static int cf=0,of=0,zf=0,sf=0;
|
||||
static int sp=0;
|
||||
static unsigned char framebuffer[320*200];
|
||||
|
||||
static SDL_Surface *sdl_screen=NULL;
|
||||
|
||||
struct palette {
|
||||
unsigned char red[256];
|
||||
unsigned char green[256];
|
||||
unsigned char blue[256];
|
||||
};
|
||||
|
||||
static struct palette pal;
|
||||
|
||||
static int mode13h_graphics_init(void) {
|
||||
|
||||
int mode;
|
||||
|
||||
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(320, 200, 32, mode);
|
||||
|
||||
if ( sdl_screen == NULL ) {
|
||||
fprintf(stderr, "ERROR! Couldn't set 320x200 video mode: %s\n",
|
||||
SDL_GetError());
|
||||
return -1;
|
||||
}
|
||||
SDL_EnableKeyRepeat(SDL_DEFAULT_REPEAT_DELAY, SDL_DEFAULT_REPEAT_INTERVAL);
|
||||
|
||||
SDL_WM_SetCaption("memories -- Linux/C/SDL","memories");
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int mode13h_graphics_update(unsigned char *buffer, struct palette *pal) {
|
||||
|
||||
unsigned int *t_pointer;
|
||||
|
||||
int x,temp;
|
||||
|
||||
/* point to SDL output pixels */
|
||||
t_pointer=((Uint32 *)sdl_screen->pixels);
|
||||
|
||||
for(x=0;x<320*200;x++) {
|
||||
|
||||
temp=(pal->red[buffer[x]]<<16)|
|
||||
(pal->green[buffer[x]]<<8)|
|
||||
(pal->blue[buffer[x]]<<0)|0;
|
||||
|
||||
t_pointer[x]=temp;
|
||||
}
|
||||
|
||||
SDL_UpdateRect(sdl_screen, 0, 0, 320, 200);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void set_vga_pal(void) {
|
||||
|
||||
/* output of vgapal https://github.com/canidlogic/vgapal */
|
||||
unsigned char raw_pal[3*256]=
|
||||
{ 0, 0, 0, 0, 0, 170, 0, 170, 0, 0, 170, 170,
|
||||
170, 0, 0, 170, 0, 170, 170, 85, 0, 170, 170, 170,
|
||||
85, 85, 85, 85, 85, 255, 85, 255, 85, 85, 255, 255,
|
||||
255, 85, 85, 255, 85, 255, 255, 255, 85, 255, 255, 255,
|
||||
0, 0, 0, 20, 20, 20, 32, 32, 32, 44, 44, 44,
|
||||
56, 56, 56, 69, 69, 69, 81, 81, 81, 97, 97, 97,
|
||||
113, 113, 113, 130, 130, 130, 146, 146, 146, 162, 162, 162,
|
||||
182, 182, 182, 203, 203, 203, 227, 227, 227, 255, 255, 255,
|
||||
0, 0, 255, 65, 0, 255, 125, 0, 255, 190, 0, 255,
|
||||
255, 0, 255, 255, 0, 190, 255, 0, 125, 255, 0, 65,
|
||||
255, 0, 0, 255, 65, 0, 255, 125, 0, 255, 190, 0,
|
||||
255, 255, 0, 190, 255, 0, 125, 255, 0, 65, 255, 0,
|
||||
0, 255, 0, 0, 255, 65, 0, 255, 125, 0, 255, 190,
|
||||
0, 255, 255, 0, 190, 255, 0, 125, 255, 0, 65, 255,
|
||||
125, 125, 255, 158, 125, 255, 190, 125, 255, 223, 125, 255,
|
||||
255, 125, 255, 255, 125, 223, 255, 125, 190, 255, 125, 158,
|
||||
255, 125, 125, 255, 158, 125, 255, 190, 125, 255, 223, 125,
|
||||
255, 255, 125, 223, 255, 125, 190, 255, 125, 158, 255, 125,
|
||||
125, 255, 125, 125, 255, 158, 125, 255, 190, 125, 255, 223,
|
||||
125, 255, 255, 125, 223, 255, 125, 190, 255, 125, 158, 255,
|
||||
182, 182, 255, 199, 182, 255, 219, 182, 255, 235, 182, 255,
|
||||
255, 182, 255, 255, 182, 235, 255, 182, 219, 255, 182, 199,
|
||||
255, 182, 182, 255, 199, 182, 255, 219, 182, 255, 235, 182,
|
||||
255, 255, 182, 235, 255, 182, 219, 255, 182, 199, 255, 182,
|
||||
182, 255, 182, 182, 255, 199, 182, 255, 219, 182, 255, 235,
|
||||
182, 255, 255, 182, 235, 255, 182, 219, 255, 182, 199, 255,
|
||||
0, 0, 113, 28, 0, 113, 56, 0, 113, 85, 0, 113,
|
||||
113, 0, 113, 113, 0, 85, 113, 0, 56, 113, 0, 28,
|
||||
113, 0, 0, 113, 28, 0, 113, 56, 0, 113, 85, 0,
|
||||
113, 113, 0, 85, 113, 0, 56, 113, 0, 28, 113, 0,
|
||||
0, 113, 0, 0, 113, 28, 0, 113, 56, 0, 113, 85,
|
||||
0, 113, 113, 0, 85, 113, 0, 56, 113, 0, 28, 113,
|
||||
56, 56, 113, 69, 56, 113, 85, 56, 113, 97, 56, 113,
|
||||
113, 56, 113, 113, 56, 97, 113, 56, 85, 113, 56, 69,
|
||||
113, 56, 56, 113, 69, 56, 113, 85, 56, 113, 97, 56,
|
||||
113, 113, 56, 97, 113, 56, 85, 113, 56, 69, 113, 56,
|
||||
56, 113, 56, 56, 113, 69, 56, 113, 85, 56, 113, 97,
|
||||
56, 113, 113, 56, 97, 113, 56, 85, 113, 56, 69, 113,
|
||||
81, 81, 113, 89, 81, 113, 97, 81, 113, 105, 81, 113,
|
||||
113, 81, 113, 113, 81, 105, 113, 81, 97, 113, 81, 89,
|
||||
113, 81, 81, 113, 89, 81, 113, 97, 81, 113, 105, 81,
|
||||
113, 113, 81, 105, 113, 81, 97, 113, 81, 89, 113, 81,
|
||||
81, 113, 81, 81, 113, 89, 81, 113, 97, 81, 113, 105,
|
||||
81, 113, 113, 81, 105, 113, 81, 97, 113, 81, 89, 113,
|
||||
0, 0, 65, 16, 0, 65, 32, 0, 65, 48, 0, 65,
|
||||
65, 0, 65, 65, 0, 48, 65, 0, 32, 65, 0, 16,
|
||||
65, 0, 0, 65, 16, 0, 65, 32, 0, 65, 48, 0,
|
||||
65, 65, 0, 48, 65, 0, 32, 65, 0, 16, 65, 0,
|
||||
0, 65, 0, 0, 65, 16, 0, 65, 32, 0, 65, 48,
|
||||
0, 65, 65, 0, 48, 65, 0, 32, 65, 0, 16, 65,
|
||||
32, 32, 65, 40, 32, 65, 48, 32, 65, 56, 32, 65,
|
||||
65, 32, 65, 65, 32, 56, 65, 32, 48, 65, 32, 40,
|
||||
65, 32, 32, 65, 40, 32, 65, 48, 32, 65, 56, 32,
|
||||
65, 65, 32, 56, 65, 32, 48, 65, 32, 40, 65, 32,
|
||||
32, 65, 32, 32, 65, 40, 32, 65, 48, 32, 65, 56,
|
||||
32, 65, 65, 32, 56, 65, 32, 48, 65, 32, 40, 65,
|
||||
44, 44, 65, 48, 44, 65, 52, 44, 65, 60, 44, 65,
|
||||
65, 44, 65, 65, 44, 60, 65, 44, 52, 65, 44, 48,
|
||||
65, 44, 44, 65, 48, 44, 65, 52, 44, 65, 60, 44,
|
||||
65, 65, 44, 60, 65, 44, 52, 65, 44, 48, 65, 44,
|
||||
44, 65, 44, 44, 65, 48, 44, 65, 52, 44, 65, 60,
|
||||
44, 65, 65, 44, 60, 65, 44, 52, 65, 44, 48, 65,
|
||||
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
||||
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
|
||||
};
|
||||
|
||||
int i;
|
||||
|
||||
for(i=0;i<256;i++) {
|
||||
pal.red[i]=raw_pal[i*3];
|
||||
pal.green[i]=raw_pal[(i*3)+1];
|
||||
pal.blue[i]=raw_pal[(i*3)+2];
|
||||
|
||||
}
|
||||
return;
|
||||
|
||||
}
|
||||
|
||||
static int graphics_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 27;
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
return 0;
|
||||
|
||||
}
|
||||
|
||||
|
||||
static void write_framebuffer(int address, int value) {
|
||||
int real_addr;
|
||||
|
||||
real_addr=address-0xa0000;
|
||||
if ((real_addr<0) || (real_addr>320*200)) return;
|
||||
|
||||
framebuffer[real_addr]=value;
|
||||
|
||||
}
|
||||
|
||||
/* unsigned multiply */
|
||||
static void mul_16(unsigned short value) {
|
||||
unsigned int result;
|
||||
|
||||
result=ax*value;
|
||||
|
||||
// printf("%x*%x=%x ",value,ax,result);
|
||||
|
||||
ax=result&0xffff;
|
||||
dx=result>>16;
|
||||
|
||||
// printf("%x:%x x=%d y=%d\n",dx,ax,
|
||||
// dx&0xff,(dx>>8)&0xff);
|
||||
|
||||
|
||||
|
||||
|
||||
if (dx==0) {
|
||||
of=0;
|
||||
cf=0;
|
||||
}
|
||||
else {
|
||||
of=1;
|
||||
cf=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
static void imul(short value) {
|
||||
int result;
|
||||
|
||||
result=ax*value;
|
||||
|
||||
ax=result&0xffff;
|
||||
dx=result>>16;
|
||||
|
||||
}
|
||||
*/
|
||||
|
||||
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_8(char value) {
|
||||
|
||||
short result;
|
||||
char src;
|
||||
|
||||
src=ax;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
ax=result;
|
||||
|
||||
if (ax==(ax&0xff)) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_16(short value) {
|
||||
|
||||
int result;
|
||||
short src;
|
||||
|
||||
src=ax;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
ax=(result&0xffff);
|
||||
dx=((result>>16)&0xffff);
|
||||
|
||||
if (dx==0) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_16_bx(short value) {
|
||||
|
||||
int result;
|
||||
short src;
|
||||
|
||||
src=bx;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
bx=(result&0xffff);
|
||||
|
||||
if (bx==result) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_16_dx(short value) {
|
||||
|
||||
int result;
|
||||
short src;
|
||||
|
||||
src=dx;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
dx=(result&0xffff);
|
||||
|
||||
if (dx==result) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
/* unsigned divide */
|
||||
static void div_8(unsigned char value) {
|
||||
|
||||
unsigned char r,q;
|
||||
unsigned int result,remainder;
|
||||
|
||||
// printf("Dividing %d (%x) by %d (%x): ",ax,ax,value,value);
|
||||
|
||||
if (value==0) {
|
||||
printf("Divide by zero!\n");
|
||||
return;
|
||||
}
|
||||
|
||||
result=ax/value;
|
||||
remainder=ax%value;
|
||||
|
||||
q=result;
|
||||
r=remainder;
|
||||
|
||||
// printf("Result: q=%d r=%d\n",q,r);
|
||||
|
||||
ax=(r<<8)|(q&0xff);
|
||||
|
||||
}
|
||||
|
||||
|
||||
|
||||
static void push(int value) {
|
||||
//printf("Pushing %x\n",value);
|
||||
stack[sp]=value;
|
||||
sp++;
|
||||
}
|
||||
|
||||
static short pop(void) {
|
||||
if (sp==0) {
|
||||
printf("Stack underflow!\n");
|
||||
return 0;
|
||||
}
|
||||
|
||||
sp--;
|
||||
|
||||
//printf("Popping %x\n",stack[sp]);
|
||||
|
||||
return stack[sp];
|
||||
|
||||
}
|
||||
/* tilted plane */
|
||||
/* DH=Y, DL=X */
|
||||
static void fx0(void) {
|
||||
|
||||
char ah,al,dh,dl;
|
||||
unsigned short temp;
|
||||
|
||||
ax=0x1329; // mov ax,0x1329 init
|
||||
|
||||
al=ax&0xff; ah=(ax>>8)&0xff;
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
|
||||
dh=dh+al; // add dh,al ; prevent divide overflow
|
||||
div_8(dh); // div dh ; reverse divide AL=C/Y'
|
||||
|
||||
dx=((dh&0xff)<<8)|dl;
|
||||
|
||||
temp=ax;
|
||||
ax=dx; dx=temp; // xchg dx,ax ; DL=C/Y' AL=X
|
||||
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
imul_8(dl); // imul dl
|
||||
dx=dx-bp; // sub dx,bp
|
||||
dl=dx&0xff;
|
||||
|
||||
ah=(ax>>8)&0xff;
|
||||
ah=ah^dl; // xor ah,dl
|
||||
al=ah; // mov al,ah
|
||||
ax=((ah&0xff)<<8)|(al&0xff);
|
||||
|
||||
ax&=0xff1c; // and al,4+8+16
|
||||
}
|
||||
|
||||
/* circles? */
|
||||
/* DH=Y, DL=X */
|
||||
static void fx1(void) {
|
||||
|
||||
int temp;
|
||||
char al,dh,ah;
|
||||
|
||||
// mov al,dh ; get Y in AL
|
||||
al=(dx>>8)&0xff;
|
||||
// sub al,100 ; align Y vertically
|
||||
al=al-100;
|
||||
ax=ax&0xff00;
|
||||
ax=ax|al;
|
||||
// imul al ; AL=Y*Y
|
||||
imul_8(al);
|
||||
// xchg dx,ax ; Y*Y/256 in DH, X in AL
|
||||
temp=ax;
|
||||
ax=dx;
|
||||
dx=temp;
|
||||
// imul al ; AL=X*X
|
||||
imul_8(ax&0xff);
|
||||
// add dh,ah ; DH=X*X+Y*Y/256
|
||||
dh=(dx>>8)&0xff;
|
||||
ah=(ax>>8)&0xff;
|
||||
dh=dh+ah;
|
||||
// mov al,dh ; AL = X*X+Y*Y/256
|
||||
al=dh;
|
||||
|
||||
dx=dx&0xff;
|
||||
dx|=(dh<<8);
|
||||
ax=(ah<<8)|(al&0xff);
|
||||
|
||||
// add ax,bp ; offset color by time
|
||||
ax=ax+bp;
|
||||
// and al,8+16 ; select special rings
|
||||
ax=ax&0xff18;
|
||||
}
|
||||
|
||||
/* checkers */
|
||||
static void fx2(void) {
|
||||
int temp;
|
||||
unsigned char al;
|
||||
|
||||
temp=ax;
|
||||
ax=dx; dx=temp; // xchg dx,ax
|
||||
ax=ax-bp; // sub ax,bp
|
||||
temp=((ax>>8)&0xff)^(ax&0xff);
|
||||
ax=ax&0xff00;
|
||||
ax|=temp; // xor al,ah
|
||||
ax|=0xdb; // or al,0xdb
|
||||
al=ax&0xff;
|
||||
al=al+0x13;
|
||||
ax=ax&0xff00;
|
||||
ax=ax|al; // add al,13h
|
||||
// ret
|
||||
|
||||
}
|
||||
|
||||
|
||||
/* parallax checkrboard */
|
||||
static void fx3(void) {
|
||||
|
||||
cx=bp; // mov cx,bp ; set init point to time
|
||||
bx=-16; // mov bx,-16 ; limit to 16 iterations
|
||||
fx3L:
|
||||
cx=cx+di; // add cx, di ; offset by screenpointer
|
||||
ax=819; // mov ax,819 ; magic, related to Rrrola
|
||||
imul_16(cx); // imul cx ; get X',Y' in DX
|
||||
cf=dx&1; // ror dx,1 ; set carry flag on "hit"
|
||||
dx=dx>>1;
|
||||
if (cf) {
|
||||
dx|=0x8000;
|
||||
}
|
||||
else {
|
||||
dx&=0x7fff;
|
||||
}
|
||||
|
||||
bx++; // inc bx ; increment iteration count
|
||||
if (bx==0) zf=1;// does not affect carry flag
|
||||
else zf=0;
|
||||
// ja fx3L ; loop until "hit" or "iter=max"
|
||||
// jump above, if cf==0 and zf==0
|
||||
if ((cf==0) && (zf==0)) goto fx3L;
|
||||
|
||||
ax=bx+31; // lea ax,[bx+32] ; map value to standard gray scale
|
||||
//printf("%d %d\n",ax,bx);
|
||||
}
|
||||
|
||||
/* sierpinski rotozoomer */
|
||||
static void fx4(void) {
|
||||
|
||||
unsigned char dl,dh,bh,al;
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
cx=bp-2048; // lea cx,[bp-2048] ; center time to pass zero
|
||||
cx=cx<<3; // sal cx,3 ; speed up by factor of 8!
|
||||
ax=(dh&0xff); // movzx ax,dh ; get X into AL
|
||||
// movsx dx,dl ; get Y into DL
|
||||
if (dl&0x80) {
|
||||
dx|=0xff00;
|
||||
}
|
||||
else {
|
||||
dx&=0x00ff;
|
||||
}
|
||||
|
||||
bx=ax; // mov bx,ax ; save X in BX
|
||||
imul_16_bx(cx); // imul bx,cx ; BX=X*T
|
||||
|
||||
/* bl=bx&0xff; */ bh=(bx>>8)&0xff;
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
bh=bh+dl; // add bh,dl ; bh=x*t/256+Y
|
||||
|
||||
imul_16_dx(cx); // imul dx,cx ; dx=Y*T
|
||||
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
// sub al,dh ; al=X-Y*T/256
|
||||
al=ax&0xff; // ah=(ax>>8)&0xff;
|
||||
al=al-dh;
|
||||
|
||||
// and al,bh ; AL=(X-Y*T/256)&(x*T/256+Y)
|
||||
al=al&bh;
|
||||
al=al&252; // and al,252 ; thicker sierpinksi
|
||||
if (al==0) zf=1;
|
||||
else zf=0;
|
||||
cf=0; of=0;
|
||||
// salc ; set pixel value to black
|
||||
if (cf==0) al=0;
|
||||
else al=0xff;
|
||||
|
||||
/* NOTE: remove the line below and the background becomes a rainbow */
|
||||
ax=al;
|
||||
// jnz fx4q ; leave black if not sierpinksi
|
||||
if (zf==0) goto fx4q;
|
||||
|
||||
ax=ax&0xff00; // mov al,0x2a ; otherwise: a nice orange
|
||||
ax|=0x2a;
|
||||
fx4q:
|
||||
;
|
||||
}
|
||||
|
||||
|
||||
/* raycast bent tunnel */
|
||||
static void fx5(void) {
|
||||
|
||||
unsigned char al,cl;
|
||||
unsigned short temp;
|
||||
|
||||
cx=cx&0xff00;
|
||||
cx|=(-9&0xff); // mov cl,-9 ; start with depth 9 (moves backwards)
|
||||
fx5L:
|
||||
cl=cx&0xff;
|
||||
|
||||
push(dx); // push dx ; save DX, destroyed inside loop
|
||||
al=(dx>>8)&0xff;// mov al,dh ; get Y into AL
|
||||
al-=100; // sub al,100 ; centering Y manually
|
||||
|
||||
ax=ax&0xff00;
|
||||
ax|=(al&0xff);
|
||||
|
||||
imul_8(cl); // imul cl ; multiply AL=Y by current distance to get projection
|
||||
// xchg ax,dx ; gt X into AL while saving DX
|
||||
temp=ax;
|
||||
ax=dx;
|
||||
dx=temp;
|
||||
|
||||
al=ax&0xff;
|
||||
al+=cl; // add al,cl ; add distance to projection (bend right)
|
||||
|
||||
ax=ax&0xff00;
|
||||
ax|=(al&0xff);
|
||||
imul_8(cl); // imul cl ; multiply AL=X by the current projection
|
||||
al=(dx>>8)&0xff;// mov al,dh ; get projection(1) in AL
|
||||
al^=(ax>>8); // xor al,ah ; combine with projection(2)
|
||||
al+=4; // add al,4 ; center the walls around 0
|
||||
if (al&-8) { // test al,-8 ; test if the wall is hit
|
||||
zf=0;
|
||||
}
|
||||
else {
|
||||
zf=1;
|
||||
}
|
||||
|
||||
dx=pop(); // pop dx (restore dx)
|
||||
cx&=0xff00;
|
||||
cx|=(cl&0xff);
|
||||
cx--;
|
||||
if ((cx!=0) && (zf==1)) goto fx5L;
|
||||
// loopz fx5L (repeat until "hit" or "iter=max"
|
||||
|
||||
cx=cx-bp; // sub cx,bp ; offset depth by time
|
||||
al^=(cx&0xff); // xor al,cl ; XOR pattern for texture
|
||||
// ah=al/6;
|
||||
al=al%6; // aam 6 ; irregular pattern with MOD 6
|
||||
al+=20; // add al,20 ; offset into grayscale pattern
|
||||
ax=al&0xff;
|
||||
}
|
||||
|
||||
/* ocean night */
|
||||
static void fx6(void) {
|
||||
char dh;
|
||||
double f;
|
||||
int edx;
|
||||
char scratch[64];
|
||||
|
||||
// bx coming in is the address of the effect
|
||||
// this is a guess, too lazy to hexdump
|
||||
bx=0x1d5;
|
||||
|
||||
// si=?? based on sound playing?
|
||||
// ax (sky color) is ?
|
||||
|
||||
dh=dx>>8;
|
||||
// sub dh,120 ; check if pixel in the sky
|
||||
dh=dh-120;
|
||||
sf=!!(dh&0x80);
|
||||
// js fx6q ; quit if that's the case
|
||||
if (sf) goto fx6q;
|
||||
|
||||
dx&=0xff;
|
||||
dx|=dh<<8;
|
||||
|
||||
// mov [bx+si],dx ; move xy to memory location
|
||||
// fild word [bx+si] ; read as integer
|
||||
// fidivr dword [bx+si] ; reverse divide by constant
|
||||
// Divide m32int by ST(0) and store result in ST(0)
|
||||
// fstp dword [bx+si-1] ; store result as floating point
|
||||
// mov ax,[bx+si] ; get result into ax
|
||||
|
||||
memcpy(&scratch[32],&dx,sizeof(short));
|
||||
f=dx;
|
||||
memcpy(&edx,&scratch[32],sizeof(int));
|
||||
f=f/edx;
|
||||
memcpy(&scratch[31],&f,sizeof(double));
|
||||
memcpy(&ax,&scratch[32],sizeof(short));
|
||||
|
||||
|
||||
|
||||
|
||||
ax+=bp; // add ax,bp ; modify color by time
|
||||
ax&=0xff80; // and al,128 ; threshold into two bands
|
||||
ax--; // dec ax ; beautify colors to blue/black
|
||||
fx6q: ;
|
||||
}
|
||||
|
||||
|
||||
int main(int argc, char **argv) {
|
||||
|
||||
int temp;
|
||||
|
||||
set_vga_pal();
|
||||
|
||||
mode13h_graphics_init();
|
||||
|
||||
di=0; // ??
|
||||
|
||||
ax=0x13; // mov al,0x13
|
||||
// int 0x10 ; set 320x200x256 color mode
|
||||
bp=ax; // xchg bp,ax ; set bp to 0x13
|
||||
|
||||
push(0xa000-10); // write screen address to es
|
||||
es=pop(); // pop es
|
||||
ax=0x251c; // mov ax,0x251c param for timer interrupt
|
||||
dx=0xdead; // mov dl, timer set up timer interrupt
|
||||
// int 0x21
|
||||
|
||||
top:
|
||||
ax=0xcccd; // load rrrola constant
|
||||
mul_16(di); // multiply
|
||||
temp=(ax&0xff)+((ax>>8)&0xff); // add al,ah
|
||||
ax=ax&0xff00;
|
||||
ax|=(temp&0xff);
|
||||
ax=ax&0xff; // xor ah,ah
|
||||
ax=ax+bp; // add ax,bp
|
||||
ax=ax>>9; // shr ax,9
|
||||
ax=ax&0xff0f; // and al,15
|
||||
temp=ax; // xchg bx,ax
|
||||
ax=bx;
|
||||
bx=temp;
|
||||
bx=bx&0xff; // mov bh,1
|
||||
bx|=1<<8;
|
||||
// printf("%x: bx\n",bx);
|
||||
// mov bl,[byte bx+table]
|
||||
// call bx
|
||||
switch (bx&0xff) {
|
||||
case 0: fx2(); break;
|
||||
case 1: fx1(); break;
|
||||
case 2: fx0(); break;
|
||||
case 3: fx3(); break;
|
||||
case 4: fx4(); break;
|
||||
case 5: fx5(); break;
|
||||
case 6: fx6(); break;
|
||||
case 7: goto end;
|
||||
default: printf("Trying effect %d\n",bx&0xff);
|
||||
}
|
||||
// stosb
|
||||
write_framebuffer((es<<4)+di, ax&0xff);
|
||||
di++;
|
||||
|
||||
// printf("Writing %d to %x (%x:%x)\n",ax&0xff,(es<<4)+di,es,di);
|
||||
di++; // inc di
|
||||
di++; // inc di
|
||||
if (di!=0) goto top;
|
||||
// printf("Done frame\n");
|
||||
mode13h_graphics_update(framebuffer,&pal);
|
||||
|
||||
// timer emulate
|
||||
usleep(10000);
|
||||
bp=bp+1;
|
||||
// mov al,tempo
|
||||
// out 40h,al (set timing?)
|
||||
// in al,0x60 read keyboad
|
||||
// dec al
|
||||
|
||||
if (graphics_input()) {
|
||||
return 0;
|
||||
}
|
||||
|
||||
// jnz top
|
||||
|
||||
goto top;
|
||||
end:
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
|
@ -0,0 +1,746 @@
|
|||
/* A Linux/SDL/C version of Hellmood's amazing 256B DOS Memories Demo */
|
||||
|
||||
/* See http://www.sizecoding.org/wiki/Memories for a rundown on how it works */
|
||||
|
||||
/* This is a conversion to C I did in an attempt to see how it works */
|
||||
/* and also to see if I could port any of this to the Apple II */
|
||||
|
||||
/* x86 has amazing code density with powerful instructions */
|
||||
/* stos, mul, div, FPU, lots of 1-byte instructions */
|
||||
/* and old x86 hardware made it really easy to program with limited code */
|
||||
/* VGA/MCGA Mode13h (320x200 256 colors linear framebuffer) */
|
||||
/* soundblaster MIDI with only a few out instructions */
|
||||
|
||||
/* Anyway this is a rough attempt to getting things going in C */
|
||||
/* The last effect (ocean) is doing lots of sketchy stuff and */
|
||||
/* depending a bit on undefined behavior so it's hit or miss */
|
||||
/* whether it will work for you */
|
||||
|
||||
/* deater -- Vince Weaver -- vince@deater.net -- 23 April 2020 */
|
||||
|
||||
#include <stdio.h>
|
||||
#include <unistd.h>
|
||||
|
||||
#include <SDL.h>
|
||||
|
||||
static unsigned short stack[128];
|
||||
static unsigned short ax,bx,cx,dx,di,bp,es;
|
||||
static int cf=0,of=0,zf=0,sf=0;
|
||||
static int sp=0;
|
||||
static unsigned char framebuffer[320*200];
|
||||
|
||||
static SDL_Surface *sdl_screen=NULL;
|
||||
|
||||
struct palette {
|
||||
unsigned char red[256];
|
||||
unsigned char green[256];
|
||||
unsigned char blue[256];
|
||||
};
|
||||
|
||||
static struct palette pal;
|
||||
|
||||
static int mode13h_graphics_init(void) {
|
||||
|
||||
int mode;
|
||||
|
||||
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(320, 200, 32, mode);
|
||||
|
||||
if ( sdl_screen == NULL ) {
|
||||
fprintf(stderr, "ERROR! Couldn't set 320x200 video mode: %s\n",
|
||||
SDL_GetError());
|
||||
return -1;
|
||||
}
|
||||
SDL_EnableKeyRepeat(SDL_DEFAULT_REPEAT_DELAY, SDL_DEFAULT_REPEAT_INTERVAL);
|
||||
|
||||
SDL_WM_SetCaption("memories -- Linux/C/SDL","memories");
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int mode13h_graphics_update(unsigned char *buffer, struct palette *pal) {
|
||||
|
||||
unsigned int *t_pointer;
|
||||
|
||||
int x,temp;
|
||||
|
||||
/* point to SDL output pixels */
|
||||
t_pointer=((Uint32 *)sdl_screen->pixels);
|
||||
|
||||
for(x=0;x<320*200;x++) {
|
||||
|
||||
temp=(pal->red[buffer[x]]<<16)|
|
||||
(pal->green[buffer[x]]<<8)|
|
||||
(pal->blue[buffer[x]]<<0)|0;
|
||||
|
||||
t_pointer[x]=temp;
|
||||
}
|
||||
|
||||
SDL_UpdateRect(sdl_screen, 0, 0, 320, 200);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void set_vga_pal(void) {
|
||||
|
||||
/* output of vgapal https://github.com/canidlogic/vgapal */
|
||||
unsigned char raw_pal[3*256]=
|
||||
{ 0, 0, 0, 0, 0, 170, 0, 170, 0, 0, 170, 170,
|
||||
170, 0, 0, 170, 0, 170, 170, 85, 0, 170, 170, 170,
|
||||
85, 85, 85, 85, 85, 255, 85, 255, 85, 85, 255, 255,
|
||||
255, 85, 85, 255, 85, 255, 255, 255, 85, 255, 255, 255,
|
||||
0, 0, 0, 20, 20, 20, 32, 32, 32, 44, 44, 44,
|
||||
56, 56, 56, 69, 69, 69, 81, 81, 81, 97, 97, 97,
|
||||
113, 113, 113, 130, 130, 130, 146, 146, 146, 162, 162, 162,
|
||||
182, 182, 182, 203, 203, 203, 227, 227, 227, 255, 255, 255,
|
||||
0, 0, 255, 65, 0, 255, 125, 0, 255, 190, 0, 255,
|
||||
255, 0, 255, 255, 0, 190, 255, 0, 125, 255, 0, 65,
|
||||
255, 0, 0, 255, 65, 0, 255, 125, 0, 255, 190, 0,
|
||||
255, 255, 0, 190, 255, 0, 125, 255, 0, 65, 255, 0,
|
||||
0, 255, 0, 0, 255, 65, 0, 255, 125, 0, 255, 190,
|
||||
0, 255, 255, 0, 190, 255, 0, 125, 255, 0, 65, 255,
|
||||
125, 125, 255, 158, 125, 255, 190, 125, 255, 223, 125, 255,
|
||||
255, 125, 255, 255, 125, 223, 255, 125, 190, 255, 125, 158,
|
||||
255, 125, 125, 255, 158, 125, 255, 190, 125, 255, 223, 125,
|
||||
255, 255, 125, 223, 255, 125, 190, 255, 125, 158, 255, 125,
|
||||
125, 255, 125, 125, 255, 158, 125, 255, 190, 125, 255, 223,
|
||||
125, 255, 255, 125, 223, 255, 125, 190, 255, 125, 158, 255,
|
||||
182, 182, 255, 199, 182, 255, 219, 182, 255, 235, 182, 255,
|
||||
255, 182, 255, 255, 182, 235, 255, 182, 219, 255, 182, 199,
|
||||
255, 182, 182, 255, 199, 182, 255, 219, 182, 255, 235, 182,
|
||||
255, 255, 182, 235, 255, 182, 219, 255, 182, 199, 255, 182,
|
||||
182, 255, 182, 182, 255, 199, 182, 255, 219, 182, 255, 235,
|
||||
182, 255, 255, 182, 235, 255, 182, 219, 255, 182, 199, 255,
|
||||
0, 0, 113, 28, 0, 113, 56, 0, 113, 85, 0, 113,
|
||||
113, 0, 113, 113, 0, 85, 113, 0, 56, 113, 0, 28,
|
||||
113, 0, 0, 113, 28, 0, 113, 56, 0, 113, 85, 0,
|
||||
113, 113, 0, 85, 113, 0, 56, 113, 0, 28, 113, 0,
|
||||
0, 113, 0, 0, 113, 28, 0, 113, 56, 0, 113, 85,
|
||||
0, 113, 113, 0, 85, 113, 0, 56, 113, 0, 28, 113,
|
||||
56, 56, 113, 69, 56, 113, 85, 56, 113, 97, 56, 113,
|
||||
113, 56, 113, 113, 56, 97, 113, 56, 85, 113, 56, 69,
|
||||
113, 56, 56, 113, 69, 56, 113, 85, 56, 113, 97, 56,
|
||||
113, 113, 56, 97, 113, 56, 85, 113, 56, 69, 113, 56,
|
||||
56, 113, 56, 56, 113, 69, 56, 113, 85, 56, 113, 97,
|
||||
56, 113, 113, 56, 97, 113, 56, 85, 113, 56, 69, 113,
|
||||
81, 81, 113, 89, 81, 113, 97, 81, 113, 105, 81, 113,
|
||||
113, 81, 113, 113, 81, 105, 113, 81, 97, 113, 81, 89,
|
||||
113, 81, 81, 113, 89, 81, 113, 97, 81, 113, 105, 81,
|
||||
113, 113, 81, 105, 113, 81, 97, 113, 81, 89, 113, 81,
|
||||
81, 113, 81, 81, 113, 89, 81, 113, 97, 81, 113, 105,
|
||||
81, 113, 113, 81, 105, 113, 81, 97, 113, 81, 89, 113,
|
||||
0, 0, 65, 16, 0, 65, 32, 0, 65, 48, 0, 65,
|
||||
65, 0, 65, 65, 0, 48, 65, 0, 32, 65, 0, 16,
|
||||
65, 0, 0, 65, 16, 0, 65, 32, 0, 65, 48, 0,
|
||||
65, 65, 0, 48, 65, 0, 32, 65, 0, 16, 65, 0,
|
||||
0, 65, 0, 0, 65, 16, 0, 65, 32, 0, 65, 48,
|
||||
0, 65, 65, 0, 48, 65, 0, 32, 65, 0, 16, 65,
|
||||
32, 32, 65, 40, 32, 65, 48, 32, 65, 56, 32, 65,
|
||||
65, 32, 65, 65, 32, 56, 65, 32, 48, 65, 32, 40,
|
||||
65, 32, 32, 65, 40, 32, 65, 48, 32, 65, 56, 32,
|
||||
65, 65, 32, 56, 65, 32, 48, 65, 32, 40, 65, 32,
|
||||
32, 65, 32, 32, 65, 40, 32, 65, 48, 32, 65, 56,
|
||||
32, 65, 65, 32, 56, 65, 32, 48, 65, 32, 40, 65,
|
||||
44, 44, 65, 48, 44, 65, 52, 44, 65, 60, 44, 65,
|
||||
65, 44, 65, 65, 44, 60, 65, 44, 52, 65, 44, 48,
|
||||
65, 44, 44, 65, 48, 44, 65, 52, 44, 65, 60, 44,
|
||||
65, 65, 44, 60, 65, 44, 52, 65, 44, 48, 65, 44,
|
||||
44, 65, 44, 44, 65, 48, 44, 65, 52, 44, 65, 60,
|
||||
44, 65, 65, 44, 60, 65, 44, 52, 65, 44, 48, 65,
|
||||
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
|
||||
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
|
||||
};
|
||||
|
||||
int i;
|
||||
|
||||
for(i=0;i<256;i++) {
|
||||
pal.red[i]=raw_pal[i*3];
|
||||
pal.green[i]=raw_pal[(i*3)+1];
|
||||
pal.blue[i]=raw_pal[(i*3)+2];
|
||||
|
||||
}
|
||||
return;
|
||||
|
||||
}
|
||||
|
||||
static int graphics_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 27;
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
return 0;
|
||||
|
||||
}
|
||||
|
||||
|
||||
static void write_framebuffer(int address, int value) {
|
||||
int real_addr;
|
||||
|
||||
real_addr=address-0xa0000;
|
||||
if ((real_addr<0) || (real_addr>320*200)) return;
|
||||
|
||||
framebuffer[real_addr]=value;
|
||||
|
||||
}
|
||||
|
||||
/* unsigned multiply */
|
||||
static void mul_16(unsigned short value) {
|
||||
unsigned int result;
|
||||
|
||||
result=ax*value;
|
||||
|
||||
// printf("%x*%x=%x ",value,ax,result);
|
||||
|
||||
ax=result&0xffff;
|
||||
dx=result>>16;
|
||||
|
||||
// printf("%x:%x x=%d y=%d\n",dx,ax,
|
||||
// dx&0xff,(dx>>8)&0xff);
|
||||
|
||||
|
||||
|
||||
|
||||
if (dx==0) {
|
||||
of=0;
|
||||
cf=0;
|
||||
}
|
||||
else {
|
||||
of=1;
|
||||
cf=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/*
|
||||
static void imul(short value) {
|
||||
int result;
|
||||
|
||||
result=ax*value;
|
||||
|
||||
ax=result&0xffff;
|
||||
dx=result>>16;
|
||||
|
||||
}
|
||||
*/
|
||||
|
||||
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_8(char value) {
|
||||
|
||||
short result;
|
||||
char src;
|
||||
|
||||
src=ax;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
ax=result;
|
||||
|
||||
if (ax==(ax&0xff)) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_16(short value) {
|
||||
|
||||
int result;
|
||||
short src;
|
||||
|
||||
src=ax;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
ax=(result&0xffff);
|
||||
dx=((result>>16)&0xffff);
|
||||
|
||||
if (dx==0) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_16_bx(short value) {
|
||||
|
||||
int result;
|
||||
short src;
|
||||
|
||||
src=bx;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
bx=(result&0xffff);
|
||||
|
||||
if (bx==result) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
/* signed multiply */
|
||||
static void imul_16_dx(short value) {
|
||||
|
||||
int result;
|
||||
short src;
|
||||
|
||||
src=dx;
|
||||
|
||||
result=src*value;
|
||||
|
||||
// printf("imul: %d*%d=%d ",src,value,result);
|
||||
|
||||
dx=(result&0xffff);
|
||||
|
||||
if (dx==result) {
|
||||
cf=0;
|
||||
of=0;
|
||||
}
|
||||
else {
|
||||
cf=1;
|
||||
of=1;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
/* unsigned divide */
|
||||
static void div_8(unsigned char value) {
|
||||
|
||||
unsigned char r,q;
|
||||
unsigned int result,remainder;
|
||||
|
||||
// printf("Dividing %d (%x) by %d (%x): ",ax,ax,value,value);
|
||||
|
||||
if (value==0) {
|
||||
printf("Divide by zero!\n");
|
||||
return;
|
||||
}
|
||||
|
||||
result=ax/value;
|
||||
remainder=ax%value;
|
||||
|
||||
q=result;
|
||||
r=remainder;
|
||||
|
||||
// printf("Result: q=%d r=%d\n",q,r);
|
||||
|
||||
ax=(r<<8)|(q&0xff);
|
||||
|
||||
}
|
||||
|
||||
|
||||
|
||||
static void push(int value) {
|
||||
//printf("Pushing %x\n",value);
|
||||
stack[sp]=value;
|
||||
sp++;
|
||||
}
|
||||
|
||||
static short pop(void) {
|
||||
if (sp==0) {
|
||||
printf("Stack underflow!\n");
|
||||
return 0;
|
||||
}
|
||||
|
||||
sp--;
|
||||
|
||||
//printf("Popping %x\n",stack[sp]);
|
||||
|
||||
return stack[sp];
|
||||
|
||||
}
|
||||
/* tilted plane */
|
||||
/* DH=Y, DL=X */
|
||||
static void fx0(void) {
|
||||
|
||||
char ah,al,dh,dl;
|
||||
unsigned short temp;
|
||||
|
||||
ax=0x1329; // mov ax,0x1329 init
|
||||
|
||||
al=ax&0xff; ah=(ax>>8)&0xff;
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
|
||||
dh=dh+al; // add dh,al ; prevent divide overflow
|
||||
div_8(dh); // div dh ; reverse divide AL=C/Y'
|
||||
|
||||
dx=((dh&0xff)<<8)|dl;
|
||||
|
||||
temp=ax;
|
||||
ax=dx; dx=temp; // xchg dx,ax ; DL=C/Y' AL=X
|
||||
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
imul_8(dl); // imul dl
|
||||
dx=dx-bp; // sub dx,bp
|
||||
dl=dx&0xff;
|
||||
|
||||
ah=(ax>>8)&0xff;
|
||||
ah=ah^dl; // xor ah,dl
|
||||
al=ah; // mov al,ah
|
||||
ax=((ah&0xff)<<8)|(al&0xff);
|
||||
|
||||
ax&=0xff1c; // and al,4+8+16
|
||||
}
|
||||
|
||||
/* circles? */
|
||||
/* DH=Y, DL=X */
|
||||
static void fx1(void) {
|
||||
|
||||
int temp;
|
||||
char al,dh,ah;
|
||||
|
||||
// mov al,dh ; get Y in AL
|
||||
al=(dx>>8)&0xff;
|
||||
// sub al,100 ; align Y vertically
|
||||
al=al-100;
|
||||
ax=ax&0xff00;
|
||||
ax=ax|al;
|
||||
// imul al ; AL=Y*Y
|
||||
imul_8(al);
|
||||
// xchg dx,ax ; Y*Y/256 in DH, X in AL
|
||||
temp=ax;
|
||||
ax=dx;
|
||||
dx=temp;
|
||||
// imul al ; AL=X*X
|
||||
imul_8(ax&0xff);
|
||||
// add dh,ah ; DH=X*X+Y*Y/256
|
||||
dh=(dx>>8)&0xff;
|
||||
ah=(ax>>8)&0xff;
|
||||
dh=dh+ah;
|
||||
// mov al,dh ; AL = X*X+Y*Y/256
|
||||
al=dh;
|
||||
|
||||
dx=dx&0xff;
|
||||
dx|=(dh<<8);
|
||||
ax=(ah<<8)|(al&0xff);
|
||||
|
||||
// add ax,bp ; offset color by time
|
||||
ax=ax+bp;
|
||||
// and al,8+16 ; select special rings
|
||||
ax=ax&0xff18;
|
||||
}
|
||||
|
||||
/* checkers */
|
||||
static void fx2(void) {
|
||||
int temp;
|
||||
unsigned char al;
|
||||
|
||||
temp=ax;
|
||||
ax=dx; dx=temp; // xchg dx,ax
|
||||
ax=ax-bp; // sub ax,bp
|
||||
temp=((ax>>8)&0xff)^(ax&0xff);
|
||||
ax=ax&0xff00;
|
||||
ax|=temp; // xor al,ah
|
||||
ax|=0xdb; // or al,0xdb
|
||||
al=ax&0xff;
|
||||
al=al+0x13;
|
||||
ax=ax&0xff00;
|
||||
ax=ax|al; // add al,13h
|
||||
// ret
|
||||
|
||||
}
|
||||
|
||||
|
||||
/* parallax checkrboard */
|
||||
static void fx3(void) {
|
||||
|
||||
cx=bp; // mov cx,bp ; set init point to time
|
||||
bx=-16; // mov bx,-16 ; limit to 16 iterations
|
||||
fx3L:
|
||||
cx=cx+di; // add cx, di ; offset by screenpointer
|
||||
ax=819; // mov ax,819 ; magic, related to Rrrola
|
||||
imul_16(cx); // imul cx ; get X',Y' in DX
|
||||
cf=dx&1; // ror dx,1 ; set carry flag on "hit"
|
||||
dx=dx>>1;
|
||||
if (cf) {
|
||||
dx|=0x8000;
|
||||
}
|
||||
else {
|
||||
dx&=0x7fff;
|
||||
}
|
||||
|
||||
bx++; // inc bx ; increment iteration count
|
||||
if (bx==0) zf=1;// does not affect carry flag
|
||||
else zf=0;
|
||||
// ja fx3L ; loop until "hit" or "iter=max"
|
||||
// jump above, if cf==0 and zf==0
|
||||
if ((cf==0) && (zf==0)) goto fx3L;
|
||||
|
||||
ax=bx+31; // lea ax,[bx+32] ; map value to standard gray scale
|
||||
//printf("%d %d\n",ax,bx);
|
||||
}
|
||||
|
||||
/* sierpinski rotozoomer */
|
||||
static void fx4(void) {
|
||||
|
||||
unsigned char dl,dh,bh,al;
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
cx=bp-2048; // lea cx,[bp-2048] ; center time to pass zero
|
||||
cx=cx<<3; // sal cx,3 ; speed up by factor of 8!
|
||||
ax=(dh&0xff); // movzx ax,dh ; get X into AL
|
||||
// movsx dx,dl ; get Y into DL
|
||||
if (dl&0x80) {
|
||||
dx|=0xff00;
|
||||
}
|
||||
else {
|
||||
dx&=0x00ff;
|
||||
}
|
||||
|
||||
bx=ax; // mov bx,ax ; save X in BX
|
||||
imul_16_bx(cx); // imul bx,cx ; BX=X*T
|
||||
|
||||
/* bl=bx&0xff; */ bh=(bx>>8)&0xff;
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
bh=bh+dl; // add bh,dl ; bh=x*t/256+Y
|
||||
|
||||
imul_16_dx(cx); // imul dx,cx ; dx=Y*T
|
||||
|
||||
dl=dx&0xff; dh=(dx>>8)&0xff;
|
||||
|
||||
// sub al,dh ; al=X-Y*T/256
|
||||
al=ax&0xff; // ah=(ax>>8)&0xff;
|
||||
al=al-dh;
|
||||
|
||||
// and al,bh ; AL=(X-Y*T/256)&(x*T/256+Y)
|
||||
al=al&bh;
|
||||
al=al&252; // and al,252 ; thicker sierpinksi
|
||||
if (al==0) zf=1;
|
||||
else zf=0;
|
||||
cf=0; of=0;
|
||||
// salc ; set pixel value to black
|
||||
if (cf==0) al=0;
|
||||
else al=0xff;
|
||||
|
||||
/* NOTE: remove the line below and the background becomes a rainbow */
|
||||
ax=al;
|
||||
// jnz fx4q ; leave black if not sierpinksi
|
||||
if (zf==0) goto fx4q;
|
||||
|
||||
ax=ax&0xff00; // mov al,0x2a ; otherwise: a nice orange
|
||||
ax|=0x2a;
|
||||
fx4q:
|
||||
;
|
||||
}
|
||||
|
||||
|
||||
/* raycast bent tunnel */
|
||||
static void fx5(void) {
|
||||
|
||||
unsigned char al,cl;
|
||||
unsigned short temp;
|
||||
|
||||
cx=cx&0xff00;
|
||||
cx|=(-9&0xff); // mov cl,-9 ; start with depth 9 (moves backwards)
|
||||
fx5L:
|
||||
cl=cx&0xff;
|
||||
|
||||
push(dx); // push dx ; save DX, destroyed inside loop
|
||||
al=(dx>>8)&0xff;// mov al,dh ; get Y into AL
|
||||
al-=100; // sub al,100 ; centering Y manually
|
||||
|
||||
ax=ax&0xff00;
|
||||
ax|=(al&0xff);
|
||||
|
||||
imul_8(cl); // imul cl ; multiply AL=Y by current distance to get projection
|
||||
// xchg ax,dx ; gt X into AL while saving DX
|
||||
temp=ax;
|
||||
ax=dx;
|
||||
dx=temp;
|
||||
|
||||
al=ax&0xff;
|
||||
al+=cl; // add al,cl ; add distance to projection (bend right)
|
||||
|
||||
ax=ax&0xff00;
|
||||
ax|=(al&0xff);
|
||||
imul_8(cl); // imul cl ; multiply AL=X by the current projection
|
||||
al=(dx>>8)&0xff;// mov al,dh ; get projection(1) in AL
|
||||
al^=(ax>>8); // xor al,ah ; combine with projection(2)
|
||||
al+=4; // add al,4 ; center the walls around 0
|
||||
if (al&-8) { // test al,-8 ; test if the wall is hit
|
||||
zf=0;
|
||||
}
|
||||
else {
|
||||
zf=1;
|
||||
}
|
||||
|
||||
dx=pop(); // pop dx (restore dx)
|
||||
cx&=0xff00;
|
||||
cx|=(cl&0xff);
|
||||
cx--;
|
||||
if ((cx!=0) && (zf==1)) goto fx5L;
|
||||
// loopz fx5L (repeat until "hit" or "iter=max"
|
||||
|
||||
cx=cx-bp; // sub cx,bp ; offset depth by time
|
||||
al^=(cx&0xff); // xor al,cl ; XOR pattern for texture
|
||||
// ah=al/6;
|
||||
al=al%6; // aam 6 ; irregular pattern with MOD 6
|
||||
al+=20; // add al,20 ; offset into grayscale pattern
|
||||
ax=al&0xff;
|
||||
}
|
||||
|
||||
/* ocean night */
|
||||
static void fx6(void) {
|
||||
char dh;
|
||||
double f;
|
||||
int edx;
|
||||
char scratch[64];
|
||||
|
||||
// bx coming in is the address of the effect
|
||||
// this is a guess, too lazy to hexdump
|
||||
bx=0x1d5;
|
||||
|
||||
// si=?? based on sound playing?
|
||||
// ax (sky color) is ?
|
||||
|
||||
dh=dx>>8;
|
||||
// sub dh,120 ; check if pixel in the sky
|
||||
dh=dh-120;
|
||||
sf=!!(dh&0x80);
|
||||
// js fx6q ; quit if that's the case
|
||||
if (sf) goto fx6q;
|
||||
|
||||
dx&=0xff;
|
||||
dx|=dh<<8;
|
||||
|
||||
// mov [bx+si],dx ; move xy to memory location
|
||||
// fild word [bx+si] ; read as integer
|
||||
// fidivr dword [bx+si] ; reverse divide by constant
|
||||
// Divide m32int by ST(0) and store result in ST(0)
|
||||
// fstp dword [bx+si-1] ; store result as floating point
|
||||
// mov ax,[bx+si] ; get result into ax
|
||||
|
||||
memcpy(&scratch[32],&dx,sizeof(short));
|
||||
f=dx;
|
||||
memcpy(&edx,&scratch[32],sizeof(int));
|
||||
f=f/edx;
|
||||
memcpy(&scratch[31],&f,sizeof(double));
|
||||
memcpy(&ax,&scratch[32],sizeof(short));
|
||||
|
||||
|
||||
|
||||
|
||||
ax+=bp; // add ax,bp ; modify color by time
|
||||
ax&=0xff80; // and al,128 ; threshold into two bands
|
||||
ax--; // dec ax ; beautify colors to blue/black
|
||||
fx6q: ;
|
||||
}
|
||||
|
||||
|
||||
int main(int argc, char **argv) {
|
||||
|
||||
int temp;
|
||||
|
||||
set_vga_pal();
|
||||
|
||||
mode13h_graphics_init();
|
||||
|
||||
di=0;
|
||||
bp=0x13; // xchg bp,ax ; set bp to 0x13
|
||||
es=0xa000-10;
|
||||
|
||||
while(1) {
|
||||
|
||||
ax=0xcccd; // load rrrola constant
|
||||
mul_16(di); // multiply
|
||||
temp=(ax&0xff)+((ax>>8)&0xff); // add al,ah
|
||||
ax=ax&0xff00;
|
||||
ax|=(temp&0xff);
|
||||
ax=ax&0xff; // xor ah,ah
|
||||
ax=ax+bp; // add ax,bp
|
||||
ax=ax>>9; // shr ax,9
|
||||
ax=ax&0xff0f; // and al,15
|
||||
temp=ax; // xchg bx,ax
|
||||
ax=bx;
|
||||
bx=temp;
|
||||
bx=bx&0xff; // mov bh,1
|
||||
bx|=1<<8;
|
||||
|
||||
switch (bx&0xff) {
|
||||
case 0: fx2(); break;
|
||||
case 1: fx1(); break;
|
||||
case 2: fx0(); break;
|
||||
case 3: fx3(); break;
|
||||
case 4: fx4(); break;
|
||||
case 5: fx5(); break;
|
||||
case 6: fx6(); break;
|
||||
case 7: goto end;
|
||||
default: printf("Trying effect %d\n",bx&0xff);
|
||||
}
|
||||
// stosb
|
||||
write_framebuffer((es<<4)+di, ax&0xff);
|
||||
di++;
|
||||
|
||||
di++; // inc di
|
||||
di++; // inc di
|
||||
if (di!=0) continue;
|
||||
|
||||
mode13h_graphics_update(framebuffer,&pal);
|
||||
|
||||
usleep(10000);
|
||||
bp=bp+1;
|
||||
|
||||
if (graphics_input()) {
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
end:
|
||||
|
||||
return 0;
|
||||
}
|
||||
Loading…
Reference in New Issue