Data commit

Task/Draw-a-clock/Julia/draw-a-clock.julia

@@ -0,0 +1,83 @@
+using Gtk, Colors, Graphics, Dates
+
+const radius = 300
+const win = GtkWindow("Clock", radius, radius)
+const can = GtkCanvas()
+push!(win, can)
+
+global drawcontext = []
+
+function drawline(ctx, l, color)
+    isempty(l) && return
+    p = first(l)
+    move_to(ctx, p.x, p.y)
+    set_source(ctx, color)
+    for i = 2:length(l)
+        p = l[i]
+        line_to(ctx, p.x, p.y)
+    end
+    stroke(ctx)
+end
+
+function clockbody(ctx)
+    set_coordinates(ctx, BoundingBox(0, 100, 0, 100))
+    rectangle(ctx, 0, 0, 100, 100)
+    set_source(ctx, colorant"yellow")
+    fill(ctx)
+    set_source(ctx, colorant"blue")
+    arc(ctx, 50, 50, 45, 45, 360)
+    stroke(ctx)
+    for hr in 1:12
+        radians = hr * pi / 6.0
+        drawline(ctx, [Point(50 + 0.95 * 45 * sin(radians),
+            50 - 0.95 * 45 * cos(radians)),
+            Point(50 + 1.0 * 45 * sin(radians),
+            50 - 1.0 * 45 * cos(radians))], colorant"blue")
+    end
+end
+
+Gtk.draw(can) do widget
+    ctx = getgc(can)
+    if length(drawcontext) < 1
+        push!(drawcontext, ctx)
+    else
+        drawcontext[1] = ctx
+    end
+    clockbody(ctx)
+end
+
+function update(can)
+    dtim = now()
+    hr = hour(dtim)
+    mi = minute(dtim)
+    sec = second(dtim)
+    if length(drawcontext) < 1
+        return
+    end
+    ctx = drawcontext[1]
+    clockbody(ctx)
+    rad = (hr % 12) * pi / 6.0 + mi * pi / 360.0
+    drawline(ctx, [Point(50, 50),
+        Point(50 + 45 * 0.5 * sin(rad), 50 - 45 * 0.5 * cos(rad))], colorant"black")
+    stroke(ctx)
+    rad = mi * pi / 30.0  + sec * pi / 1800.0
+    drawline(ctx, [Point(50, 50),
+        Point(50 + 0.7 * 45 * sin(rad), 50 - 0.7 * 45 * cos(rad))], colorant"darkgreen")
+    stroke(ctx)
+    rad = sec * pi / 30.0
+    drawline(ctx, [Point(50, 50),
+        Point(50 + 0.9 * 45 * sin(rad), 50 - 0.9 * 45 * cos(rad))], colorant"red")
+    stroke(ctx)
+    reveal(can)
+end
+
+Gtk.showall(win)
+sloc = Base.Threads.SpinLock()
+lock(sloc)
+signal_connect(win, :destroy) do widget
+    unlock(sloc)
+end
+while !trylock(sloc)
+    update(win)
+    sleep(1.0)
+end