Rez Behaviour Catalog

The $sequence behaviour takes two or more children and, when executed, it executes each of its children in turn. If any child fails then $sequence will stop at that point and fail. If all the children suceeed then the $sequence will succeed.

The effect is like a boolean and expression. Sequences are often a set of conditions followed by a set of actions.

Metaphorically a $sequence is like a recipe, a set of steps that should be following from start to finish. If you get half way through a recipe and are missing a key ingredient, the recipe cannot be finished.

The $select behaviour takes two or more children and, when executed, it executes each of its children in turn. If any child succeeds then $select will immediately succeed without executing any further children. If all the children fail then $select will fail.

The effect is like a boolean or expression. Selects often express a range of alternative behaviours where we want only the first to succeed.

Metaphorically a $select is like the mains section of a menu, you pick an choose among the options available but don’t (at least the author tries not to) order two mains.

The $select_p behaviour is a variant on $select. It takes a probability option p and before executing any child will test p. If the test succeeds it will execute that child and behaviour similar to $select. If no children get executed or all the children fail then $select_p will fail.

The $select_r behaviour is a variant on $select. When a $select_r is executed it executes its children in a random order.

The $loop behaviour takes one child and executes it a number of times specified by the option count. If the child should fail then $loop fails. If the child succeeds each time then $loop succeeds.

The $loop_until behaviour takes one child and attempts to execute it a number of times specified by the option attempts. If the child succeeds then $loop_until succeeds. If the child never succeeds then $loop_until fails.

The $maybe behaviour takes one child and based on a probability option p decides whether to attempt to execute it or not. If the p test succeeds the child gets executed and $maybe will succeed or fail based on whether the child succeeds or fails. If the p test fails then $maybe fails.

The $either behaviour takes two children and based on the probability option p decides whether to execute the first or the second child. If the p test succeeds then the first child is executed, otherwise the second child is executed. $either succeeds or fails based on whether the child it executes succeeds or fails.

The $random_choice behaviour takes at least two children and executes one child at random. If the child succeeds then $random_choice succeeds, otherwise it fails.

The $random_each behaviour takes at least two children and executes one child at random. $random_each succeeds or fails based on the selected child succeeding or failing.

Once a child has been executed it is not eligible to be selected again until all the other children of $random_each have, likewise, been executed. When all the children have been executed $random_each will begin again with a new random order of children.

The $invert behaviour takes one child and executes it. If the child succeeds then $invert fails, likewise if the child fails then $invert will succeed.

The $always behaviour takes one child and executes it. It ignores whether the child succeeds or fails and always suceeds itself.

The $never behaviour takes one child and executes it. It ignores whether the child succeeds or fails, always failing itself. It’s a shorthand for [$invert [$always …​]].

The $succeed behaviour takes no chilren and when executed it always succeeds.

The $fail behaviour takes no children and when executed it always fails.