Advanced 12d

Version 11 of 12d Model introduced a much faster, more powerful and flexible clash detection routine. The greater flexibility is provided through the ability to create multiple rules for checking elements against one another. The rules allow strings to be filtered by model and string name, so simple and complex clash combinations can be easily created. In this post, I’ll explain how the filters are applied to the dataset to select which strings are checked against which to get you your clash results (hopefully no clashes!). The clash detection rules can be created via the Design→Check-Clash→Clash detection or Utilities→A-G→Check / clash→Clash detection menus. I won’t discuss how the rules are created in the panel or how the clash detection is actually run since the 12d Model help explains that. Instead, I’ll be explaining the concepts behind the rules and how they are used to select datasets for checking clashes.

Clash Rulesets and Rules

In order to actually run the Clash Detection, you must first select a ruleset for the check.  The ruleset defined the rule/s that 12d will use to determine whether there are any clashes.

There must be at least one clash rule in a Clash Rule Set; otherwise, there is nothing to do. If such a Clash Rule Set is used (i.e. no rules) then no results will be reported. A ruleset can, however, contain more than one rule. In such a case, when the Clash Detection is run with the ruleset, each rule will be processed separately, reported to the same, single file, but in different sections (unless the report template has been customized).

The rule defines two separate datasets for each rule – the source dataset containing the elements being checked, and the target dataset containing the elements being checked against. Elements cannot exist in both. They are in either one or the other or neither.

In order to select which elements are in the source dataset and which are in the target dataset, each rule has several filter fields. The filter fields are grouped in pairs- one for the model name, another for the string name- and there are two pairs- one for the source dataset, the other for the target dataset.  These filter fields can contain wildcards and wild characters (*, ?) and blank fields will match all elements. That is, blank fields are interpreted as the wild character * , which selects all data.

When the clash detection is run, a dataset of objects is selected by the user by using the Source Box at the top of the panel. This can be called “Dataset A“. Typically, this would contain all the modelled utilities and objects that you want to check for clashes. The source dataset and target dataset are extracted from this overall dataset. The source dataset can be called “Dataset B” and the target dataset called “Dataset C“.

The “Model to check” filter is applied first to select models from the overall dataset, Dataset A.

The “Object name to check” filter is then applied to all elements matching the “Model to check” filter. So, only strings matching both “Model to check” and “Object name to check” filters will be selected for the source dataset (Dataset B).

So, the combination of “Model to check” filter and “Object name to check” filter is applied to the overall clash detection dataset (Dataset A) selected by the user to select the source dataset (Dataset B).