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Give it some wings.

Introduction

Racer v0.8.35 introduced the start of a generalized parameter & signals system. The abstract view of the Racer application can help in tweaking parameters 'live' and checking out the results live.

The idea is that a system is created, with subsystems. Each (sub)system contains a number of parameters and signals. For example, the top system is the Racer app itself, called the 'root' system. Underneath this, loaded cars are called 'car0' for example. The cars contain subsystems, such as 'wing0'. Not all systems contains parameters and/or signals, but most lower-level systems do. The wings for example expose 'coeff_drag' and 'coeff_down' parameters. You can tweak these live using console commands.

The 'system' is a dynamically created & maintained objects; it grows as cars are added, and also the parameters exposed can vary based on how cars and other objects are configured (through car.ini for example).

The future is then to create a tool which helps in navigating and modifying the system tree parameters, possibly also logging signals.

System console commands

The system can be tweaked using these console commands:

• 'system export' - exports the system to a HTML file and opens this. More on this below.
• 'set <path> <value>' - sets a parameter value. Normally all parameters should support live editing. An example is 'set car0.wing0.coeff_down 10' to tune the downforce coefficient of the car's first wing.
• 'get <path>' - shows the parameter value. If a system is specified, it displays the child system, parameters and signals defined for that subsystem. For a full overview, use 'system export'.

System export

The system export is very useful to see what's going on inside the Racer engine. This tree can be expanded between Racer versions, so there is no one static version of the tree. However, some common properties always apply.

• The tree exposes the hierarchical parameter tree as is currently available in Racer for tweaking. Here, 'currently' means the state Racer is in at the time of a race. It may vary according to the cars being loaded.
• Each parameter can be clicked, at which it will directly go to the ccompanying Racer webpage, which explains the parameter.

(last updated November 13, 2012 )