Drawings & snapping
Importing a DXF as a reference underlay, choosing its units and plane, and snapping model geometry onto it accurately.
Modeling 3 min read
A member that ends 3 mm from a node is not connected to anything, and nothing in the results will say so directly: the member simply carries nothing, or the model check finds a mechanism.
The fastest way to get it right is to draw over the drawing that already has it. Elementarium imports DXF files as a reference underlay and lets you snap model nodes onto their geometry.
Importing a DXF
- Open the file. The import dialog reads it and reports what it found: entities, layers, blocks.
- Confirm its units. The dialog preselects what the file claims and lets you override it.
- Choose the plane and position. A plan goes on the horizontal plane at a level you give; a section or elevation goes on a vertical one.
Placement is yours to set and to change afterwards: the drawing is an object in the model with its own properties.
Arcs, circles, polylines, splines, hatches, dimensions, text and block inserts all come through. Blocks are kept as inserts, not exploded, so a drawing with two thousand identical bolt symbols stays a drawing instead of becoming two thousand entities.
Snapping
With a drawing visible, the cursor latches onto its geometry. Snap points come from the entity definitions, not from the tessellated curves the viewer draws. A circle's centre and quadrants are exact; its rendered chords are an approximation, and snapping to a chord vertex would put the node a fraction of a millimetre off.
| Snap | What it finds |
|---|---|
| Endpoint | A line end, a polyline vertex, an arc end — the highest priority, because that is what a corner is |
| Intersection | Where two entities cross |
| Center | The centre of a circle or arc |
| Midpoint | The middle of a segment |
| Quadrant | The four cardinal points of a circle |
| Insert | A block's insertion point |
| Nearest | Anywhere on an entity, when nothing better is in range |
Where several are in range, endpoint wins, then intersection, then the rest in the order above. Snapping is switched off with the SNAP toggle in the status bar, which leaves the drawing visible.
Managing drawings
A drawing is a model object like any other. Select it to change its placement, its scale, its visibility or which layers show. Several can be loaded at once — a plan at each level, an elevation on a vertical plane — and each can be turned off when it stops being useful.
Drawings are reference geometry only. Nothing in a DXF becomes a member, a node or a load; the import gives you something accurate to draw against.
Working without a drawing
Where there is no DXF, geometry is entered by coordinate. That is exact by construction, and for a portal frame or a truss it is often faster than any drawing workflow.
Related
Your first model walks through building geometry from scratch; Supports and releases covers what happens at the nodes once they are in the right place.
Something wrong or unclear on this page? Tell us, and it gets corrected.