(3D) Deterministic Bounce Prediction

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Introduction

This scene demonstrates the use of Trick Shot and the Trick Shot Line component to predict the path a thrown object and will take into account bounces.

The tool can be used to quickly and easily fire physically simulated projectiles from throwing a ball or grenade to shooting arrows, firing cannons and more. The Trick Shot tool handles all the calculations for you including launching the projectile via the "Shoot" method.

The projectile launched by Trick Shot uses the Ballistic Path Follow component which allows the projectile to accurately follow the pre-planned path and to optionally react to changes in the environment as required.

What do I Learn?

1. How to use Trick Shot to plan and execute shots
2. How to use Ballistic Path Follow to manage projectiles
3. How to display a trajectory using the Trick Shot Line component.

Objects

Emitter GameObject

The emitter game object does all the real work in the sample scene and houses:

Trick Shot

The trick shot component is used to predict a trajectory and "shoot" a projectile that will obey that planned path e.g. a Ballistic Path Follow projectile. This allows for accurate deterministic prediction of bounces and collisions, the ability to handle unexpected (dynamic) collisions and changes to the environment.

Trick Shot Constant Acceleration

Constant Acceleration simply calculates a new constant acceleration value to apply to the Trick Shot in each frame. It is an optional component and not really needed for this demo but is included here so you can play with it and see its effect. Try adding a Local Constant with a small effect on the x such as (1, 0, 0) ... doing so you should see that the projectile curves to the right as if under the influence of a Magnus effect (spin of the projectile)

You don't have to use this component if your game only needs a simple global value such as Gravity but it can be useful or just fun to use so give it a try.

Trick Shot Line

The trick shot line component is used to control the Line Renderer and draw the resulting path. It simply reads the prediction from the Trick Shot component and updates the points displayed by the Line Renderer.

Sphere GameObject

A simple stand-in for our projectile which uses the Ballistic Path Follow component to track the planned path. The options on Path Follow describe how the projectile will react to various conditions, such as rather or not it should resume a traditional dynamic physics simulation at the end of the path or on an unexpected collision.