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#include <u.h>
#include <libc.h>
#include <thread.h>
#include <draw.h>
#include <mouse.h>
#include <keyboard.h>
#include <geometry.h>
enum {
MAXMAGNITUDE = 40
};
enum {
Cbg,
Cfg,
NCOLOR
};
typedef struct Strut Strut;
struct Strut
{
Point2 v;
Strut *next;
};
RFrame worldrf;
Image *pal[NCOLOR];
Strut *struts;
Point2 origin;
Strut*
newstrut(Point2 v)
{
Strut *s;
s = malloc(sizeof(Strut));
if(s == nil)
sysfatal("malloc: %r");
setmalloctag(s, getcallerpc(&v));
s->v = v;
s->next = nil;
return s;
}
Point
toscreen(Point2 p)
{
p = invrframexform(p, worldrf);
return Pt(p.x,p.y);
}
Point2
fromscreen(Point p)
{
return rframexform(Pt2(p.x,p.y,1), worldrf);
}
void
initpalette(void)
{
pal[Cbg] = allocimage(display, Rect(0,0,1,1), screen->chan, 1, 0x000000ff);
pal[Cfg] = allocimage(display, Rect(0,0,1,1), screen->chan, 1, 0xffffffff);
}
void
redraw(void)
{
Strut *s;
Point2 p0, p1;
p0 = origin;
lockdisplay(display);
draw(screen, screen->r, pal[Cbg], nil, ZP);
for(s = struts; s != nil; s = s->next){
p1 = addpt2(p0, s->v);
line(screen, toscreen(p0), toscreen(p1), Endsquare, Endarrow, 0, pal[Cfg], ZP);
p0 = p1;
}
flushimage(display, 1);
unlockdisplay(display);
}
void
resized(void)
{
lockdisplay(display);
if(getwindow(display, Refnone) < 0)
sysfatal("resize failed");
unlockdisplay(display);
worldrf.p = Pt2(screen->r.min.x,screen->r.max.y,1);
origin = Pt2(Dx(screen->r)/2,Dy(screen->r)/2,1);
redraw();
}
void
mouse(Mouse m)
{
Strut *s;
Point2 mpos, v;
double θ;
if((m.buttons & 1) != 0){
mpos = subpt2(fromscreen(m.xy), origin);
θ = atan2(mpos.y, mpos.x);
//v = Vec2(cos(frand() * 2*PI),sin(frand() * 2*PI));
v = Vec2(cos(θ),sin(θ));
v = mulpt2(v, frand()*MAXMAGNITUDE);
s = newstrut(v);
if(struts == nil)
struts = s;
else{
s->next = struts;
struts = s;
}
}
}
void
key(Rune r)
{
switch(r){
case Kdel:
case 'q':
threadexitsall(nil);
}
}
void
usage(void)
{
fprint(2, "usage: %s\n", argv0);
exits("usage");
}
void
threadmain(int argc, char *argv[])
{
Mousectl *mc;
Keyboardctl *kc;
Rune r;
ARGBEGIN{
default: usage();
}ARGEND;
if(argc > 0)
usage();
if(initdraw(nil, nil, nil) < 0)
sysfatal("initdraw: %r");
if((mc = initmouse(nil, screen)) == nil)
sysfatal("initmouse: %r");
if((kc = initkeyboard(nil)) == nil)
sysfatal("initkeyboard: %r");
initpalette();
worldrf.p = Pt2(screen->r.min.x,screen->r.max.y,1);
worldrf.bx = Vec2(1, 0);
worldrf.by = Vec2(0,-1);
origin = Pt2(Dx(screen->r)/2,Dy(screen->r)/2,1);
display->locking = 1;
unlockdisplay(display);
redraw();
for(;;){
enum { MOUSE, RESIZE, KEYBOARD };
Alt a[] = {
{mc->c, &mc->Mouse, CHANRCV},
{mc->resizec, nil, CHANRCV},
{kc->c, &r, CHANRCV},
{nil, nil, CHANEND}
};
switch(alt(a)){
case MOUSE:
mouse(mc->Mouse);
break;
case RESIZE:
resized();
break;
case KEYBOARD:
key(r);
break;
}
redraw();
}
}
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