(Original Image by Valerie Everett)
It is sometime necessary to move an object in a physics simulation to a specific point. On the one hand, it can be difficult to analyse the exact force you have to apply; on the other hand it might not look so good if you animate the object’s position directly.
A compromise that works well in many situations is to use a spring-damper system to move the object.
The trick is simple: we apply two forces—the one is proportional to the displacement; the other is proportional to the velocity. Tweaked correctly, they combine to give realistic movement to the desired point.
Continue reading “A Simple Trick for Moving Objects in a Physics Simulation”
(Original Image by everyone’s idle.)
This post was a originally published on Luma Labs, now dead.
As old as stimulus-response techniques are, they still form an important part of many AI systems, even if it is a thin layer underneath a sophisticated decision, planning, or learning system. In this tutorial I give some advice to their design and implementation, mostly out of experience gained from implementing the AI for some racing games.
A stimulus response agent (or a reactive agent) is an agent that takes inputs from its world through sensors, and then takes action based on those inputs through actuators. Between the stimulus and response, there is a processing unit that can be arbitrarily complex. An example of such an agent is one that controls a vehicle in a racing game: the agent “looks” at the road and nearby vehicles, and then decides how much to turn and break.
Continue reading “Tips for Designing and Implementing a Stimulus Response Agent”