ref: c172881606bfa194399a0b181b419a34488331d6
dir: /sys/src/games/galaxy/galaxy.c/
#include <u.h>
#include <libc.h>
#include <bio.h>
#include <draw.h>
#include <thread.h>
#include <mouse.h>
#include <cursor.h>
#include <keyboard.h>
#include "galaxy.h"
Cursor crosscursor = {
{-7, -7},
{0x03, 0xC0, 0x03, 0xC0, 0x03, 0xC0, 0x03, 0xC0,
0x03, 0xC0, 0x03, 0xC0, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0x03, 0xC0, 0x03, 0xC0,
0x03, 0xC0, 0x03, 0xC0, 0x03, 0xC0, 0x03, 0xC0, },
{0x00, 0x00, 0x01, 0x80, 0x01, 0x80, 0x01, 0x80,
0x01, 0x80, 0x01, 0x80, 0x01, 0x80, 0x7F, 0xFE,
0x7F, 0xFE, 0x01, 0x80, 0x01, 0x80, 0x01, 0x80,
0x01, 0x80, 0x01, 0x80, 0x01, 0x80, 0x00, 0x00, }
};
Cursor zoomcursor = {
{-7, -7},
{0x1F, 0xF8, 0x3F, 0xFC, 0x7F, 0xFE, 0xFB, 0xDF,
0xF3, 0xCF, 0xE3, 0xC7, 0xFF, 0xFF, 0xFF, 0xFF,
0xFF, 0xFF, 0xFF, 0xFF, 0xE3, 0xC7, 0xF3, 0xCF,
0x7B, 0xDF, 0x7F, 0xFE, 0x3F, 0xFC, 0x1F, 0xF8, },
{0x00, 0x00, 0x0F, 0xF0, 0x31, 0x8C, 0x21, 0x84,
0x41, 0x82, 0x41, 0x82, 0x41, 0x82, 0x7F, 0xFE,
0x7F, 0xFE, 0x41, 0x82, 0x41, 0x82, 0x41, 0x82,
0x21, 0x84, 0x31, 0x8C, 0x0F, 0xF0, 0x00, 0x00, }
};
Cursor pausecursor={
0, 0,
0x01, 0x80, 0x03, 0xC0, 0x07, 0xE0, 0x07, 0xe0,
0x07, 0xe0, 0x07, 0xe0, 0x03, 0xc0, 0x0F, 0xF0,
0x1F, 0xF8, 0x1F, 0xF8, 0x1F, 0xF8, 0x1F, 0xF8,
0x0F, 0xF0, 0x1F, 0xF8, 0x3F, 0xFC, 0x3F, 0xFC,
0x01, 0x80, 0x03, 0xC0, 0x07, 0xE0, 0x04, 0x20,
0x04, 0x20, 0x06, 0x60, 0x02, 0x40, 0x0C, 0x30,
0x10, 0x08, 0x14, 0x08, 0x14, 0x28, 0x12, 0x28,
0x0A, 0x50, 0x16, 0x68, 0x20, 0x04, 0x3F, 0xFC,
};
enum {
STK = 8192,
DOBODY = 0,
SPEED,
GRAV,
SAVE,
LOAD,
EXIT,
MEND,
};
Cursor *cursor;
Mousectl *mc;
Keyboardctl kc;
double
G = 1,
θ = 1,
scale = 30,
ε = 500,
dt = .2,
LIM = 10,
dt²;
char *file;
int showv, showa, throttle, paused;
char *menustr[] = {
[DOBODY] "new body",
[SAVE] "save",
[LOAD] "load",
[SPEED] "speed",
[GRAV] "gravity",
[EXIT] "exit",
[MEND] nil
};
Menu menu = {
.item menustr
};
Image*
randcol(void)
{
static struct {
ulong c;
Image *i;
} cols[] = {
DWhite, nil,
DRed, nil,
DGreen, nil,
DCyan, nil,
DMagenta, nil,
DYellow, nil,
DPaleyellow, nil,
DDarkyellow, nil,
DDarkgreen, nil,
DPalegreen, nil,
DPalebluegreen, nil,
DPaleblue, nil,
DPalegreygreen, nil,
DYellowgreen, nil,
DGreyblue, nil,
DPalegreyblue, nil,
};
int r;
r = nrand(nelem(cols));
if(cols[r].i == nil)
cols[r].i = allocimage(display, Rect(0,0,1,1), screen->chan, 1, cols[r].c);
return cols[r].i;
}
void
pause(int p, int id)
{
static int pid = -1;
switch(p) {
default:
sysfatal("invalid pause value %d:", p);
break;
case 0:
if(pid != -1 && pid != id)
break;
pid = id;
if(paused)
break;
paused = 1;
qlock(&glxy);
break;
case 1:
if(!paused || pid != id)
break;
pid = -1;
paused = 0;
qunlock(&glxy);
break;
}
}
void
drawstats(void)
{
Point p;
static char buf[1024];
snprint(buf, sizeof(buf), "Number of bodies: %d", glxy.l);
p = addpt(screen->r.min, (Point){5, 3});
string(screen, p, display->white, ZP, font, buf);
snprint(buf, sizeof(buf), "Avg. calculations per body: %g", avgcalcs);
p = addpt(p, (Point){0, font->height});
string(screen, p, display->white, ZP, font, buf);
snprint(buf, sizeof(buf), "Max depth of quad tree: %d", quaddepth);
p = addpt(p, (Point){0, font->height});
string(screen, p, display->white, ZP, font, buf);
}
void
drawglxy(void)
{
Point pos, va;
Body *b;
int s;
draw(screen, screen->r, display->black, 0, ZP);
for(b = glxy.a; b < glxy.a + glxy.l; b++) {
pos.x = b->x / scale + orig.x;
pos.y = b->y / scale + orig.y;
s = b->size/scale;
fillellipse(screen, pos, s, s, b->col, ZP);
if(showv) {
va.x = b->v.x/scale;
va.y = b->v.y/scale;
if(va.x != 0 || va.y != 0)
line(screen, pos, addpt(pos, va), Enddisc, Endarrow, 0, b->col, ZP);
}
if(showa) {
va.x = b->a.x/scale*50;
va.y = b->a.y/scale*50;
if(va.x != 0 || va.y != 0)
line(screen, pos, addpt(pos, va), Enddisc, Endarrow, 0, b->col, ZP);
}
}
STATS(drawstats();)
flushimage(display, 1);
}
void
setsize(Body *b)
{
Point pos, d;
double h;
pos.x = b->x / scale + orig.x;
pos.y = b->y / scale + orig.y;
d = subpt(mc->xy, pos);
h = hypot(d.x, d.y);
b->size = h == 0 ? scale : h*scale;
b->mass = b->size*b->size*b->size;
}
void
setvel(Body *b)
{
Point pos, d;
pos.x = b->x / scale + orig.x;
pos.y = b->y / scale + orig.y;
d = subpt(mc->xy, pos);
b->v.x = (double)d.x*scale/10;
b->v.y = (double)d.y*scale/10;
}
void
setpos(Body *b)
{
b->x = (mc->xy.x - orig.x) * scale;
b->y = (mc->xy.y - orig.y) * scale;
}
void
dosize(Body *b)
{
Point p;
p = mc->xy;
for(;;) {
setsize(b);
drawglxy();
drawbody(b);
readmouse(mc);
if(mc->buttons != 3)
break;
}
moveto(mc, p);
}
void
dovel(Body *b)
{
Point p;
p = mc->xy;
for(;;) {
setvel(b);
drawglxy();
drawbody(b);
readmouse(mc);
if(mc->buttons != 5)
break;
}
moveto(mc, p);
}
void
dobody(void)
{
Vector gc;
double f;
Body *b;
for(;;) {
readmouse(mc);
if(mc->buttons == 0)
continue;
if(mc->buttons == 1)
break;
return;
}
b = body();
setpos(b);
setvel(b);
setsize(b);
b->col = randcol();
for(;;) {
drawglxy();
drawbody(b);
readmouse(mc);
if(!(mc->buttons & 1))
break;
if(mc->buttons == 3)
dosize(b);
else if(mc->buttons == 5)
dovel(b);
else
setpos(b);
}
CHECKLIM(b, f);
gc = center();
orig.x += gc.x / scale;
orig.y += gc.y / scale;
}
char*
getinput(char *info, char *sug)
{
static char buf[1024];
static Channel *rchan;
char *input;
int r;
if(rchan == nil)
rchan = chancreate(sizeof(Rune), 20);
if(sug != nil)
strecpy(buf, buf+1024, sug);
else
buf[0] = '\0';
kc.c = rchan;
r = enter(info, buf, sizeof(buf), mc, &kc, nil);
kc.c = nil;
if(r < 0)
sysfatal("save: could not get filename: %r");
input = strdup(buf);
if(input == nil)
sysfatal("getinput: could not save input: %r");
return input;
}
void
domove(void)
{
Point oldp, off;
setcursor(mc, &crosscursor);
oldp = mc->xy;
for(;;) {
readmouse(mc);
if(mc->buttons != 1)
break;
off = subpt(mc->xy, oldp);
oldp = mc->xy;
pause(0, 0);
orig = addpt(orig, off);
drawglxy();
pause(1, 0);
}
setcursor(mc, cursor);
}
void
dozoom(void)
{
Point z, d;
double f, olds;
setcursor(mc, &zoomcursor);
z = mc->xy;
olds = scale;
for(;;) {
readmouse(mc);
if(mc->buttons != 2)
break;
d = subpt(mc->xy, z);
f = tanh((double)d.y/200) + 1;
pause(0, 0);
scale = f*olds;
drawglxy();
pause(1, 0);
}
setcursor(mc, cursor);
pause(1, 0);
}
void
load(int fd)
{
orig = divpt(subpt(screen->r.max, screen->r.min), 2);
orig = addpt(orig, screen->r.min);
readglxy(fd);
center();
}
void
domenu(void)
{
int fd;
char *s;
double z;
pause(0, 0);
switch(menuhit(3, mc, &menu, nil)) {
case DOBODY:
dobody();
break;
case SAVE:
s = getinput("Enter file:", file);
if(s == nil || *s == '\0')
break;
free(file);
file = s;
fd = create(file, OWRITE, 0666);
if(fd < 0)
sysfatal("domenu: could not create file %s: %r", file);
writeglxy(fd);
close(fd);
break;
case LOAD:
s = getinput("Enter file:", file);
if(s == nil || *s == '\0')
break;
free(file);
file = s;
fd = open(file, OREAD);
if(fd < 0)
sysfatal("domenu: could not open file %s: %r", file);
load(fd);
close(fd);
break;
case SPEED:
s = getinput("Speed multiplier:", nil);
if(s == nil || *s == '\0')
break;
z = strtod(s, nil);
free(s);
if(z <= 0)
break;
dt *= z;
dt² = dt*dt;
break;
case GRAV:
s = getinput("Gravity multiplier:", nil);
if(s == nil || *s == '\0')
break;
z = strtod(s, nil);
free(s);
if(z <= 0)
break;
G *= z;
break;
case EXIT:
threadexitsall(nil);
break;
}
drawglxy();
pause(1, 0);
}
void
mousethread(void*)
{
threadsetname("mouse");
for(;;) {
readmouse(mc);
switch(mc->buttons) {
case 1:
domove();
break;
case 2:
dozoom();
break;
case 4:
domenu();
break;
}
}
}
void
resizethread(void*)
{
threadsetname("resize");
for(;;) {
recv(mc->resizec, nil);
pause(0, 0);
if(getwindow(display, Refnone) < 0)
sysfatal("resize failed: %r");
drawglxy();
pause(1, 0);
}
}
void
kbdthread(void*)
{
Keyboardctl *realkc;
Rune r;
threadsetname("keyboard");
realkc = initkeyboard(nil);
if(realkc == nil)
sysfatal("kbdthread: could not initkeyboard: %r");
for(;;) {
recv(realkc->c, &r);
if(r == Kdel) {
threadexitsall(nil);
}
if(kc.c != nil)
send(kc.c, &r);
else switch(r) {
case 'q':
threadexitsall(nil);
break;
case 's':
stats ^= 1;
break;
case 'v':
showv ^= 1;
break;
case 'a':
showa ^= 1;
break;
case ' ':
if(paused) {
cursor = nil;
pause(1, 1);
} else {
cursor = &pausecursor;
pause(0, 1);
}
setcursor(mc, cursor);
}
drawglxy();
}
}
/* verlet barnes-hut */
void
simulate(void*)
{
Body *b;
double f;
threadsetname("simulate");
for(;;) {
qlock(&glxy);
if(throttle)
sleep(throttle);
drawglxy();
Again:
space.t = EMPTY;
quads.l = 0;
STATS(quaddepth = 0;)
for(b = glxy.a; b < glxy.a + glxy.l; b++) {
if(quadins(b, LIM) == -1) {
growquads();
goto Again;
}
}
STATS(avgcalcs = 0;)
for(b = glxy.a; b < glxy.a + glxy.l; b++) {
b->a.x = b->newa.x;
b->a.y = b->newa.y;
b->newa.x = b->newa.y = 0;
STATS(calcs = 0;)
quadcalc(b, space, LIM);
STATS(avgcalcs += calcs;)
}
STATS(avgcalcs /= glxy.l;)
for(b = glxy.a; b < glxy.a + glxy.l; b++) {
b->x += dt*b->v.x + dt²*b->a.x/2;
b->y += dt*b->v.y + dt²*b->a.y/2;
b->v.x += dt*(b->a.x + b->newa.x)/2;
b->v.y += dt*(b->a.y + b->newa.y)/2;
CHECKLIM(b, f);
}
qunlock(&glxy);
}
}
void
usage(void)
{
fprint(2, "Usage: %s [-t throttle] [-G gravity] [-ε smooth] [-i] [file]\n", argv0);
threadexitsall("usage");
}
void
threadmain(int argc, char **argv)
{
int doload;
doload = 0;
ARGBEGIN {
default:
usage();
break;
case 't':
throttle = strtol(EARGF(usage()), nil, 0);
break;
case 'G':
G = strtod(EARGF(usage()), nil);
break;
case L'ε':
ε = strtod(EARGF(usage()), nil);
break;
case 'i':
doload++;
break;
} ARGEND
if(argc > 1)
usage();
fmtinstall('B', Bfmt);
if(argc == 1) {
if(doload++)
usage();
file = strdup(argv[0]);
if(file == nil)
sysfatal("threadmain: could not save file name: %r");
close(0);
if(open(file, OREAD) != 0)
sysfatal("threadmain: could not open file: %r");
}
if(initdraw(nil, nil, "Galaxy") < 0)
sysfatal("initdraw failed: %r");
if(mc = initmouse(nil, screen), mc == nil)
sysfatal("initmouse failed: %r");
dt² = dt*dt;
orig = divpt(subpt(screen->r.max, screen->r.min), 2);
orig = addpt(orig, screen->r.min);
glxyinit();
quadsinit();
if(doload)
load(0);
close(0);
threadcreate(mousethread, nil, STK);
threadcreate(resizethread, nil, STK);
threadcreate(kbdthread, nil, STK);
proccreate(simulate, nil, STK);
threadexits(nil);
}