How to update v-for output in Vue?

Question

Vue.js

I am making a square map editor based on a regular array.
I wrote down the following, on the top panel, select the type of block that will be placed and click on the map in the center, however, after clicking, the output of the array using v-for is not updated, although the console shows that the array has been updated.
How to fix it? Please help.

Answer 1

You should still read the documentation :
Accordingly, instead of let it be

this.$set(this.terain[x], y, Number(this.cursorBlock))