Click and hold to create circles. Update: 20180209: space key can be used to generate a random circle. Update: 20180209: "c" key can be used to generate a random circle at origin.
Purely pen Update: 20181218: Add round to mouse xy-coordinates so that it is compatible with Scratch 3.0's decimal precision in coordinates Update: 20180209: The array is finally changed to 240x360, while each element stores 2 characters, so now every single pixel can be stored and it becomes smoother. Color detection always fails since it detects all directions, therefore a list is used instead to achieve this. However, array with length of 480x360 is not supported, so 240x180 is used instead.