Data commit

Task/Draw-a-sphere/Jq/draw-a-sphere-1.jq

@@ -0,0 +1,19 @@
+def svg:
+  "<svg width='100%' height='100%' version='1.1'
+    xmlns='http://www.w3.org/2000/svg'
+    xmlns:xlink='http://www.w3.org/1999/xlink'>" ;
+
+# A radial gradient to make a circle look like a sphere.
+# "colors" should be [startColor, intermediateColor, endColor]
+# or null for ["white", "teal", "black"]
+def sphericalGradient(id; colors):
+  "<defs>
+        <radialGradient id = '\(id)' cx = '30%' cy = '30%' r = '100%' fx='10%' fy='10%' >
+            <stop stop-color = '\(colors[0]//"white")' offset =   '0%'/>
+            <stop stop-color = '\(colors[1]//"teal")'  offset =  '50%'/>
+            <stop stop-color = '\(colors[1]//"black")' offset = '100%'/>
+        </radialGradient>
+    </defs>" ;
+
+def sphere(cx; cy; r; gradientId):
+   "<circle fill='url(#\(gradientId))' cx='\(cx)' cy='\(cy)' r='\(r)' />" ;

Task/Draw-a-sphere/Jq/draw-a-sphere-2.jq

@@ -0,0 +1,9 @@
+def draw_sphere:
+  svg,
+   "<title>Teal sphere</title>",
+    sphericalGradient("tealGradient"; null), # define the gradient to use
+    sphere(100;100;100; "tealGradient"),     # draw a sphere using the gradient
+    sphere(100;300;100; "tealGradient"),     # draw another sphere using the same gradient
+  "</svg>" ;
+
+draw_sphere

Task/Draw-a-sphere/Jq/draw-a-sphere-3.jq

@@ -0,0 +1 @@
+$ jq -r -n -f spheres.jq > spheres.svg