Use the keys 1-7 to alter the values of variables. Here are the keys description: 1) Thickness of the lines. 2) Amount of sides. 3) Radius of the Gonggi. 4) Wave amplitude on the sides of the Gonggi. 5) Wave amount. 6) Inner shape. 7) Inner shape to edge distance.
This is mobile friendly, to change the variables of the Gonggi, you tap the screen to change the key you want to press. Once you have selected the one you have in mind, hold tap and then change the variable. The top right will show you which key you are going to change. Don't worry about when your hold tapping.