Smart Dimension: values, formulas and reference dimensions
Dimension a sketch with one tool: click one or two items and place the label; type a number, a formula with parameters, or name = value to create a parameter. Driving vs reference dimensions, and how dimensions show up in the Recipe.
Smart Dimension (D in sketch mode) picks the right kind of dimension from what you click, just like SolidWorks' Smart Dimension or Onshape's Dimension tool.
Click, place, type
- Press D.
- Click one item, or two.
- Click where the label should go.
- Type the value and press Enter. Esc keeps the measured value.
| You click | You get |
|---|---|
| A line | Its length (for a slanted line, place the label above or beside it for the horizontal or vertical length) |
| A circle / an arc | Diameter / radius |
| Two points (or the origin and a point) | Horizontal, vertical or aligned distance — decided by where you place the label |
| A point and a line | Perpendicular distance |
| Two parallel lines | Distance between them |
| Two lines at an angle | The angle (on the side you place the label) |
| A circle and a line, or two circles | Distance from the center(s) |
The tool stays active for the next dimension. Drag a label to move it; click it to change the value.
Values and formulas
A dimension takes the same expressions as any value in Solid Vibes:
- a number:
40 - a parameter:
width - a formula:
width / 2 - wall,2 * (bolt_d + 0.4),cos(30) * size - a new parameter:
depth = 40creates the parameter depth (40 mm) and makes the dimension use it.
The input shows what the value evaluates to as you type, and suggests matching parameter names. Dimensions that use parameters show both (width = 80) on the label.
Driving and reference dimensions
A driving dimension sets the geometry. A reference (driven) dimension only measures it and is shown in parentheses, like (48.5).
If you dimension something that is already defined, the dimension is added as a reference so the sketch doesn't become over-defined. Type a different value to make it driving — if that conflicts with other constraints it turns red and tells you which. Select any dimension to switch it between driving and reference.
In the Recipe
The sketch's Recipe sentence shows its key dimensions as editable chips — formulas and parameters first. Changing a chip re-solves the sketch in the kernel and rebuilds everything after it, exactly like changing the dimension in sketch mode. If a value makes the sketch impossible (a fillet bigger than its corner, a triangle whose sides can't meet), the step turns red with the reason.
By prompt or voice
In sketch mode, select an item and say or type "add a dimension of 40", "dimension it width / 2" or "fully define this sketch".
For SolidWorks, Fusion and Onshape users
| You know | Here |
|---|---|
| Smart Dimension / Sketch Dimension / Dimension | Smart Dimension (D) |
| Driven dimension / reference dimension | Reference dimension (parentheses) |
| Equations, linked values | Parameters and formulas in the value |
| Fully Define Sketch / Fully constrain | Fully define (wand) or "fully define this sketch" |
| Blue / black / red sketch colours | Same meaning: under-defined, fully defined, over-defined |
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