aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
-rw-r--r--beziers.c128
-rw-r--r--mkfile1
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();
+}
diff --git a/mkfile b/mkfile
index f54cc91..896b94c 100644
--- a/mkfile
+++ b/mkfile
@@ -3,5 +3,6 @@
BIN=/$objtype/bin/etoys
TARG=\
triangles\
+ beziers\
</sys/src/cmd/mkmany