How to cut the cake into three pieces?

Taking the cake picture as an example, the cutting method is as follows:

Step 1: Take the center point of the cake height, make the first plane cut, and divide the cake into two equal layers.

Step 2: cut the second knife in the middle of the upper dot and cut the upper layer of the cake in half.

Step 3: Take the center point of the upper layer, cut the third knife vertically through the second knife, and divide the upper layer of the cake into four pieces on average.

Step 4: Because each step is equally divided, the top four pieces of the divided cake are the same size, and the bottom is the same. It is finished by cutting eight pieces with three knives.