1 files changed, 29 insertions, 0 deletions
diff --git a/examples/script/context2d/scripts/translate.js b/examples/script/context2d/scripts/translate.js
new file mode 100644
index 0000000..7c94433
--- /dev/null
+++ b/examples/script/context2d/scripts/translate.js
@@ -0,0 +1,29 @@
+  var ctx = document.getElementById('tutorial').getContext('2d');
+  ctx.fillRect(0,0,300,300);
+  for (var i=0;i<3;i++) {
+    for (var j=0;j<3;j++) {
+      ctx.save();
+      ctx.strokeStyle = "#9CFF00";
+      ctx.translate(50+j*100,50+i*100);
+      drawSpirograph(ctx,20*(j+2)/(j+1),-8*(i+3)/(i+1),10);
+      ctx.restore();
+    }
+  }
+
+function drawSpirograph(ctx,R,r,O){
+  var x1 = R-O;
+  var y1 = 0;
+  var i  = 1;
+  ctx.beginPath();
+  ctx.moveTo(x1,y1);
+  do {
+    if (i>20000) break;
+    var x2 = (R+r)*Math.cos(i*Math.PI/72) - (r+O)*Math.cos(((R+r)/r)*(i*Math.PI/72))
+    var y2 = (R+r)*Math.sin(i*Math.PI/72) - (r+O)*Math.sin(((R+r)/r)*(i*Math.PI/72))
+    ctx.lineTo(x2,y2);
+    x1 = x2;
+    y1 = y2;
+    i++;
+  } while (x2 != R-O && y2 != 0 );
+  ctx.stroke();
+}