# How many DI trajectories are there against up-throw chain-throw?

I play Falco. Fox, Marth, and Peach each have an up-throw chain-grab/throw on him.

I know that there are differing trajectories given no DI, slightly behind, fully behind/in, or fully forward/away DI. Are those all of the trajectories, or are there more?

Melee can distinguish between a total of 352 control stick angles overall (source with image), with about a 17-degree range at the four orthogonal angles where it assumes you want pure horizontal or vertical. Each of these different angles will give you a different amount of DI. As DI is based on being orthogonal to the impending knockback, this means that in theory you have ~177 choices of DI. Obviously it isn't practical to try and pick one specifically, but it's how it is.

However, there is a wrinkle. While Fox's up throw is a perfect 90 degrees, Peach's is 88, and Marth's is 93. As a result, you don't get equal distance on either side: you can move farther sideways (but less vertically) if you DI Peach's forwards and Marth's backwards. In addition, because these angles are within 17 degrees of orthogonal, no "perfect maximum DI" angle for them exists (such angles get swallowed by the pure horizontal/vertical assumer).

In short: Treat DI as if it is analog and not digital, and realize that you get less DI out of attacks within 17 degrees of orthogonal (but not exactly orthogonal).

This GIF displays all trajectories:

In the gif Fox has DIed upthrow horizontally at possible inputs (all possible x-values from fully left to fully right). The result of each is shown sequentially.

The arrow and bar on the bottom show the position of the stick, and the result of that input.

The green region is a clear demonstration of "slight DI". Some people aren't aware of this kind of DI input, or believe that only the angle of input matters during DI, so hopefully this gif should be educational for some!

An example of using slight DI is during Marth's chaingrab on spacies. DIing slightly behind Marth forces him to have to pivot grab, which is harder to execute.