Developing a Flight System

smallguy

As it stands, Brickadia does not have a system in place for facilitating flight for vehicles. However, it does introduce "exec" gates that allow us to manipulate the velocity and rotation of a grid via wires. Combining this with a clock and player input enable flight to be simulated. This has already been demonstrated by multiple players on the discord and flight systems can be seen on some of the popular freebuilds and in Fish's dogfight server.

I haven't followed how these were made and wanted to document my own process for achieving flight using these limited systems, and see if I can make any improvements along the way.

I will be using the Regulus Missile as the test bed for the flight system, as it is the only air based vehicle I've built in Brickadia.

smallguy

The only component that needs to be on the vehicle itself is the "Read Brick Grid" gate. This provides a reference or "handle" to the physics grid it is attached to, and allows us to manipulate that grid. There are two non-obvious properties of this grid handle.

1. Instead of being organized with the other "exec" gates this gate is found in the "pure" wires category
2. The grid handle can not be used to read current position, rotation, velocity, etc. It can only be used as a setter of state.

smallguy

Because we can't use the read brick gate to get the current state of the grid, we will have to keep track of it ourselves. This implies we will need a storage system. The way this is done before variable gates have been introduced is with blend gates fed back into themselves. A buffer is required for any cycle in wires v2, but can be set to 0 tick to allow sub-tick updates.

smallguy

This also means we will have to calculate the rotation of the vehicle ourselves. The simplest approach is using euler angles, which means we will need the ability to perform trigonometric functions. We don't have real gates for doing trig, but we can use approximation functions to get close enough. For my design I want to try using the Bhāskara I's sine approximation formula. Even though it uses a lot of gates it will be calculated quickly in wires v2.

smallguy

We can not use the approximation on it's own though, since it expects the input to be in the range from 0° to 180°.
To hangle negative values from 0° to -180° we check the sign and multiple the input and output by -1 if the sign is negative.

smallguy

This assumes still that our variable will be constrained to -180 to 180 degrees. Enforcing this is fairly simple, we just want to roll over from 180 degrees to -180 degrees to go full circle.

smallguy

we can now make a rotation "register" using these building blocks
the individual angles are constrained to -180 to 180 degrees, and are set simultaneously
as input it takes the delta to these angles and outputs the current angles

smallguy

Now things can get exciting. I wanted to test what I had so far, and demonstrate having complete control of the rotation of the grid in 3d space using the rotation register. A once per tick clock is used to trigger the "exec" gates for setting rotation as well as setting the velocity to 6.5 upwards per tick to keep it floating in space

smallguy

A once-per-tick clock is made by taking a normal clock and exec-unioning either side of it

Totodile

Nice, so we will get semi working planes at the end, right?

What can you guys do with wires is awesome