Blocks

A block combines elements into a reusable part. The geometry is stored once in the drawing as a block definition; every visible copy is a block instance that only knows its position, rotation and scale. Change the definition and all instances follow. Blocks are the basis of the parts lists and of the standard parts.

This page describes the relationships. Step by step: Create a block, Edit a block, Replace a block. Commands: Create block from selection, Edit block, Split off as variant, Replace with another block, Block manager, Load block. Dialog: Block manager. Messages: Messages about blocks, parts lists and standard parts.

Definition and instance#

The block definition has a name, the geometry in block-local coordinates (the base point lies at the origin), its own dimensions and hatches, the BOM data and a version number that increases with every edit. All definitions of a drawing are listed in the section Blocks of the panel on the right and in the Block manager.

The block instance is a single element of the drawing of type Block: insertion point, rotation angle, scale in X and Y, layer and Z level. It can be selected, moved, rotated, mirrored and scaled like any element; mirroring turns one of the two scales negative. Elements inside an instance cannot be selected individually — use the block editor or Explode instead.

A click on the name in the list or on the blue button + attaches a new instance to the mouse — see Inserting instances. The triangle in front of a row unfolds the contained sub-blocks; the eye hides and shows all instances of a definition.

Base point and insertion point#

When a block is created, the base point becomes the origin of the definition: if the gizmo pivot is set or the gizmo is visible, the program takes its position, otherwise the centre of the selection. When inserting, this point sits at the mouse. In the block editor an orange cross marks the origin — moving the geometry there means moving the insertion point. While placing, the key B picks another snap point of the block as a temporary base point (placement HUD).

Inserting instances#

After a click on a block name in the panel or on Insert in the Block manager, the block hangs at the mouse as an orange preview. Every click places an instance, the tool stays active (Block placed (n×) — keep clicking or ESC to finish). While placing, the same keys apply as for a standard part: R rotates by 90°, Shift+R back, H and V mirror, + and − scale, B resets the base point, Ctrl+wheel rotates in steps of 1°; Esc or right-click ends. Snapping applies to the base point.

A new instance lies on the active layer. Its elements keep the colour, width and line type they have in the definition; layer overrides do not affect block instances (Move layer content and On current layer leave the appearance of the instance unchanged).

Nesting#

A block definition may contain instances of other blocks: the Bearing block in the example consists of a rectangle and two instances of Hole Ø9. To do so, include instances in the selection when creating the block. A block cannot contain itself — the block editor refuses to insert the block currently being edited (A block cannot contain itself). The Block manager shows the nesting as a tree with the multiplicity ×n; the additional mark ↻ flags a cycle. Sub-blocks that only occur inside other blocks count 0× in the drawing; the Block manager lists definitions without any use under Unused blocks.

Hiding acts through the nesting: if a sub-block is hidden, it is missing in all assemblies. In that case the parts list asks whether hidden blocks should be counted (Parts lists).

Editing the definition#

The block editor opens the definition in isolation: the drawing is put aside, only the block geometry lies on the canvas in block-local coordinates, and an orange banner at the top shows Block editor · Name. All drawing and editing tools are available — including dimensions, hatches and further sub-blocks. Save writes the geometry back, increases the version number and updates all instances; Cancel discards the changes. On leaving, the drawing returns with its view and undo history. The editor cannot be opened twice (The block editor is already active).

Ways into the editor: row button 📐 in the section Blocks, Edit in the Block manager, right-click on an instance → Edit block, command search Edit block. A double-click on an instance does not open the editor but the Block manager with the block selected.

Variants#

If only some of the instances should change, split them off as a variant: the program copies the definition under the name Name (2), re-attaches the selected instances and opens the copy in the editor. The remaining instances keep the old definition. Article number and designation of the copy receive the suffix -2 and (2), so that the variant appears as its own item in the parts list. If all instances of a block are selected there is nothing to split off — then change the definition directly.

Replacing#

Replace with another block attaches selected instances to another definition; position, rotation and scale remain. From the Block manager, Replace with … replaces all instances of a block and optionally also its occurrences inside other blocks. If the old definition becomes unused, the status line reports … now unused (Clean up in the Block manager).

Block files .ldblk#

Export in the section Blocks or in the Block manager writes a definition with all its sub-blocks as file Name.ldblk into the download folder. Load block reads such a file into the current drawing: the main block immediately hangs at the mouse. If a block with the same name already exists, the program asks whether the file should be loaded as a copy; existing blocks are never overwritten. This is how you exchange blocks between drawings. For a whole library the standard part library on the server is the better choice.

Exploding#

Explode dissolves an instance into its elements: the transformed geometry becomes ordinary elements of the drawing, block-own dimensions and hatches come along. The definition remains; its row in the panel counts one instance less. Exploding is the way to change a part freely in one place without touching the other instances — the alternative with a way back is the variant. With nested blocks one step dissolves only the outermost level; the sub-blocks remain instances.

Dimensions and hatches in blocks#

When a block is created, explicitly selected dimensions and all dimensions whose references lie completely within the selection move into the definition; hatches only if they are selected. In the instance they are transformed along (the scale acts on the geometry, the dimension text shows the scaled value), but they cannot be selected individually. The eye of the system layer Dimensions and the layer Hatches also act on block-own dimensions and hatches. Details on dimensions: Dimensions in blocks.

Deleting#

A definition can only be deleted if it is not used — neither as an instance in the drawing nor inside another block. The Block manager states the reason in the window (The block is still placed n× in the drawing …, The block is contained in «…»). All unused definitions at once are removed by Clean up in the section Unused blocks. Deleting an instance (Del) leaves the definition untouched.

Layers, visibility, selection filter#

The instance lies on a layer; if it is hidden or locked, this applies to the whole instance. The eye in the section Blocks hides all instances of a definition (mark 🚫); hidden blocks also disappear from assemblies. The selection filter knows the category Blocks. In the panel Properties a selected instance shows type BLOCKREF, layer, width, colour, line style and Z level.

Print, SVG and DXF#

When printing and in SVG, instances are drawn dissolved — as on screen. In DXF the dialog DXF options, section Blocks, decides: as block (remains one part) writes a DXF block definition and one INSERT per instance with position, scale and rotation; dissolved into single parts exports as drawn. Blocks with their own dimensions or hatches carry their complete definition as payload at the INSERT, so that LiberoDraft rebuilds them as real blocks with dimensions and hatches when reading back; other CAD systems only see the graphics. On DXF import the dialog offers to explode imported blocks.

Known limits#

• Elements inside an instance cannot be selected or dimensioned individually; snap points on them work.
• The scale of an instance also acts on text and arrow sizes of block-own dimensions.
• The panel Properties shows no block-specific fields for an instance (name, insertion point, rotation, scale); change these via the gizmo, the dialog Scale or the coordinate field.