diff options
| -rw-r--r-- | beziers.c | 128 | ||||
| -rw-r--r-- | mkfile | 1 |
2 files changed, 129 insertions, 0 deletions
diff --git a/beziers.c b/beziers.c new file mode 100644 index 0000000..24c801a --- /dev/null +++ b/beziers.c @@ -0,0 +1,128 @@ +#include <u.h> +#include <libc.h> +#include <draw.h> +#include <event.h> +#include <keyboard.h> + +typedef struct Point2 Point2; +typedef struct Bézier Bézier; + +struct Point2 +{ + double x, y, w; +}; + +struct Bézier +{ + Point2 p0, p1, p2, p3; +}; + +enum { + Cbg, + Cctl, + Cbez, + NCOLOR +}; + +Image *pal[NCOLOR]; +Bézier *bezs; +Point2 pts[4]; +ulong nbez, npt; + +Point2 +Pt2(double x, double y, double w) +{ + return (Point2){x,y,w}; +} + +Point +toscreen(Point2 p) +{ + return addpt(screen->r.min, Pt(p.x,p.y)); +} + +Point2 +fromscreen(Point p) +{ + p = subpt(p, screen->r.min); + return Pt2(p.x,p.y,1); +} + +void +initpalette(void) +{ + pal[Cbg] = allocimage(display, Rect(0,0,1,1), screen->chan, 1, 0x000000ff); + pal[Cctl] = allocimage(display, Rect(0,0,1,1), screen->chan, 1, 0x00ff00ff); + pal[Cbez] = allocimage(display, Rect(0,0,1,1), screen->chan, 1, 0xff0000ff); +} + +void +redraw(void) +{ + int i; + + draw(screen, screen->r, pal[Cbg], nil, ZP); + for(i = 0; i < nbez; i++) + bezier(screen, toscreen(bezs[i].p0), toscreen(bezs[i].p1), toscreen(bezs[i].p2), toscreen(bezs[i].p3), Endsquare, Endsquare, 0, pal[Cbez], ZP); + for(i = 0; i < npt; i++) + fillellipse(screen, toscreen(pts[i]), 2, 2, pal[Cctl], ZP); + flushimage(display, 1); +} + +void +usage(void) +{ + fprint(2, "usage: %s\n", argv0); + exits("usage"); +} + +void +main(int argc, char *argv[]) +{ + Event e; + Bézier b; + + ARGBEGIN{ + default: usage(); + }ARGEND; + if(argc > 0) + usage(); + if(initdraw(nil, nil, nil) < 0) + sysfatal("initdraw: %r"); + initpalette(); + einit(Emouse|Ekeyboard); + redraw(); + for(;;) + switch(event(&e)){ + case Emouse: + if((e.mouse.buttons&1) != 0){ + pts[npt++] = fromscreen(e.mouse.xy); + if(npt >= nelem(pts)){ + b.p0 = pts[0]; + b.p1 = pts[1]; + b.p2 = pts[2]; + b.p3 = pts[3]; + bezs = realloc(bezs, ++nbez*sizeof(Bézier)); + bezs[nbez-1] = b; + npt = 0; + } + redraw(); + } + break; + case Ekeyboard: + switch(e.kbdc){ + case 'q': + case Kdel: + exits(0); + } + break; + } +} + +void +eresized(int) +{ + if(getwindow(display, Refnone) < 0) + sysfatal("resize failed"); + redraw(); +} @@ -3,5 +3,6 @@ BIN=/$objtype/bin/etoys TARG=\ triangles\ + beziers\ </sys/src/cmd/mkmany |