Data update

Task/Draw-a-clock/XPL0/draw-a-clock.xpl0

@@ -0,0 +1,48 @@
+include xpllib;         \for DrawCircle, DrawLine, LineWidth, MovePen, Deg2Rad
+def     X0=400, Y0=300; \center coordinate
+int     Hour, Minute, Second;
+
+proc    DrawHand(Angle, Length, Width, Color);
+real    Angle, Length;
+int     Width, Color;
+int     X, Y;
+[X:= fix(Length*Sin(Angle));
+ Y:= fix(Length*Cos(Angle));
+LineWidth:= Width;
+MovePen(X0, Y0);
+DrawLine(X0+X, Y0-Y, Color);
+];
+
+proc    DrawClock;      \Show analog clock with current time
+real    Angle;
+int     N, X, Y;
+[DrawCircle(X0, Y0, 299, LCyan, true);
+Angle:= 0.;
+for N:= 0 to 59 do      \draw tick marks
+        [X:= fix(260.*Cos(Angle));
+         Y:= fix(260.*Sin(Angle));
+        DrawCircle(X+X0, Y+Y0, if rem(N/5) then 4 else 8, Black, true);
+        Angle:= Angle + 6.*Deg2Rad;
+        ];
+Angle:= float((Hour*60+Minute)/2) * Deg2Rad;
+DrawHand(Angle, 210., 8, Black);
+Angle:= float((Minute*60+Second)/10) * Deg2Rad;
+DrawHand(Angle, 240., 5, Black);
+Angle:= float(Second*6) * Deg2Rad;
+DrawHand(Angle, 260., 3, LRed);
+DrawCircle(X0, Y0, 8, Black, true);
+];
+
+int     Second0;
+char    Time;
+[SetVid($103);          \800x600x8
+InitDraw;
+repeat  Time:= GetDateTime;
+        Hour:= Time(3);
+        if Hour>=12 then Hour:= Hour-12;
+        Minute:= Time(4);
+        Second:= Time(5);
+        if Second # Second0 then
+                [Second0:= Second;  DrawClock];
+until   KeyHit;
+]