Rafiki knows how to use a computer?

It's that scene where Rafiki finds out that Simba is alive. In his excitement, he quickly adds a crude mane to Simba's wiped paining on the tree.
But as he does that, the paint is added over a much larger area than his finger. In fact, it looks like when you pain in Photoshop or Gimp, where the added color is applied over an area larger then the cursor on the screen. With a computer, that's fine. They're made to do that.
But how does Rafiki manage the effect with his finger? Is Mufasa helping spread the paint?
But as he does that, the paint is added over a much larger area than his finger. In fact, it looks like when you pain in Photoshop or Gimp, where the added color is applied over an area larger then the cursor on the screen. With a computer, that's fine. They're made to do that.
But how does Rafiki manage the effect with his finger? Is Mufasa helping spread the paint?
