June 2018 Update

Task/Greyscale-bars-Display/Perl-6/greyscale-bars-display.pl6

@@ -2,11 +2,11 @@ my $wininfo = qx[xwininfo -root];
 my ($width,$height) = ($wininfo ~~ /'Width: ' (\d+) .*? 'Height: ' (\d+)/).list;
 ($width,$height) = 1280,768 unless $width;
 
-my $PGM = open "greybars.pgm", :w or die "Can't create greybars.pgm: $!";
+my $PGM = open "Greyscale-bars-perl6.pgm", :w or die "Can't create Greyscale-bars-perl6.pgm: $!";
 
 $PGM.print: qq:to/EOH/;
     P2
-    # greybars.pgm
+    # Greyscale-bars-perl6.pgm
     $width $height
     65535
     EOH
@@ -31,8 +31,6 @@ $PGM.say: $line for ^$h4;
 
 $PGM.close;
 
-shell "eog -f greybars.pgm";
-
 sub divvy($all, $div) {
     my @marks = ((1/$div,2/$div ... 1) X* $all)».round;
     @marks Z- 0,|@marks;

Task/Greyscale-bars-Display/Ring/greyscale-bars-display.ring

@@ -0,0 +1,61 @@
+# Project : Greyscale bars/Display
+# Date    : 2018/01/09
+# Author : Gal Zsolt (~ CalmoSoft ~)
+# Email   : <calmosoft@gmail.com>
+
+load "guilib.ring"
+
+paint = null
+
+new qapp
+        {
+        win1 = new qwidget() {
+                  setwindowtitle("Greyscale bars/Display")
+                  setgeometry(100,100,500,600)
+                  label1 = new qlabel(win1) {
+                              setgeometry(10,10,400,400)
+                              settext("")
+                  }
+                  new qpushbutton(win1) {
+                          setgeometry(150,500,100,30)
+                          settext("draw")
+                          setclickevent("draw()")
+                  }
+                  show()
+        }
+        exec()
+        }
+
+func draw
+        p1 = new qpicture()
+               color = new qcolor() {
+               setrgb(0,0,255,255)
+        }
+        pen = new qpen() {
+                 setcolor(color)
+                 setwidth(1)
+        }
+        paint = new qpainter() {
+                  begin(p1)
+                  setpen(pen)
+
+        for row=1 to 4
+              n=pow(2,(row+2))
+              w=1280/n
+              py=256*(4-row)
+              for b=0 to n-1
+                   g=floor(255*b/(n-1))
+                   if n=16 or n=64
+                      g=255-g
+                   ok
+                   color2 = new qcolor()
+                   color2.setrgb(g,g,g,255)
+                   mybrush = new qbrush() {setstyle(1) setcolor(color2)}
+                   paint.setbrush(mybrush)
+                   paint.drawrect(w*b,py,w,256)
+              next
+        next
+
+        endpaint()
+        }
+        label1 { setpicture(p1) show() }