I am using geometry nodes to make a grid of icons. I have instanced the icon object over a Grid node. How can I make the instances of the icon appear as if the grid is building from the bottom left to right then row after row? If I have to animate a material to make them appear then I was hoping to use the list of icons to alter properties like color or size as well as.
The Grid node is quite limited in terms of attributes. You can't do much with the resulting geometry after its creation unless you jump through mathematical hoops.
What we can do is use a Line mesh, and extract an index from its vertices position, which we will use to construct our own grid.
This setup will associate an incremented index for each vertex of the mesh.
Then we create the grid with x ≡ idx (modulo columns) and y = idx // columns (integer division).
Now we filter out the unwanted points by removing indices > our wanted value.
The entire node tree:
you can do this with this node setup:
for color you can use something like this (since you didn't specify your color...i took kind of random)
Video tutorial with step by step explanation: