One question that often comes up is “Should I use Blocks, or Groups in my drawings?” . On a quick glance, they might seem very similar, and/or apparently share some properties, but if you look closer to each one of them, you will find specific characteristics that will help you decide which ones to use, and when to use them.
EntityGroups
You can combine drawing entities into EntityGroups. Grouping entities lets you manipulate all entities within the group in a single operation (moving, rotating, mirroring, or scaling, for example). However, you can still edit individual entities in a EntityGroup (intersecting or stretching, for example).
You can add or remove entities from an EntityGroup any time. Entities can be members of more than one EntityGroup. EntityGroups can be contained in other EntityGroups.
Blocks
A Block is a collection of entities bound together as a single entity. After you create a Block, you can insert it whenever you need it in a drawing. When you use the MakeBlock command, the Block is recognized in the current drawing only. The ExportDrawing command lets you write a Block to an external drawing file for use in any drawing.
EntityGroups Vs Blocks
Taking a look at the definitions of each one of them, a couple of differences standout, but there are more differences to add:
- Groups combine multiple entities, allowing individual editing of these entities opposite to Blocks, that are a collection of entities bound together as a single entity .
- Blocks are always selected as a single object. Groups allow individual selection
- A Block has its own insertion point. An EntityGroup has none.
- A Block can occur multiple times in the drawing. If a Block is redefined, all of its occurrences update. EntityGroups do not behave the same way.
- You can copy groups. An EntityGroup that originates from another EntityGroup that has been copied is a separate union of entities. Each Block has a unique name, but not its references.
- Blocks are always selected as a single object. Groups allow individual selection.
- Groups are local to the current drawing/session (not transmitable to other drawings). Blocks can be copied between sessions/drawings.
- Blocks allow the use of attached information (Attributes).
As you can see, Groups are good combining entities that you might want to select more than once, during your design process. You can use it almost as an extension of a “Selection filter”, avoiding you the boring process to pick many objects again and again, in any given operationthroughout your design process. If on one end a Group provides flexibility within one drawing, providing an easy way to combine entities that you need to manipulate as an unit, Blocks provide you perhaps a not so flexible option, but on the other end, more powerful, in the sense that allows that more information is combined. It’s ideal if you have information that is repeated in your drawing, and/or different drawings/projects. As a rule of thumb, consider the Properties of each one of them :
Groups- Flexible, ideal for temporary use
Blocks- Usable in multiple drawings, can include Attributes.
For more information on Blocks and EntiyGroups, take a look at the DraftSight Help files, to the topics “Working with EntityGroups”, “Working with Blocks”, and “Working with Blocks, BlockAttributes, EntityGroups, References, and Hyperlinks”.
