Draft Dimension

Description
The dimension tool creates a dimension in the current document with two points defining the distance to measure, and a third point specifying where the dimension line passes.



How to use

 * 1) Press the  button, or press  then  keys
 * 2) Click a point on the 3D view, or type a coordinate
 * 3) Click a second point on the 3D view, or type a coordinate
 * 4) Click a third on the 3D view, or type a coordinate

Available dimension types

 * Linear dimensions: by picking any 2 points or any straight edge with pressed.
 * Horizontal/vertical dimensions: by pressing after the first point is selected.
 * Diameter dimensions: by picking a curved edge with pressed.
 * Radius dimensions: by picking a curved edge with pressed, then pressing.
 * Angular dimensions: by picking 2 straight edges with pressed.

Options

 * Press, or  after a point to constrain the next point on the given axis.
 * To enter coordinates manually, simply enter the numbers, then press between each X, Y and Z component.
 * Press while drawing to force snapping your point to the nearest snap location, independently of the distance.
 * Pressing will constrain the dimension horizontally or vertically, or, when working on a circular edge, switches between diameter and radius modes.
 * Press or click the checkbox to check/uncheck the  button. If relative mode is on, the coordinates of the next point are relative to the last one. If not, they are absolute, taken from the (0,0,0) origin point.
 * Press or click the checkbox to check/uncheck the  button. If continue mode is on, you will be able to draw continued dimensions, one after the other, that share the same baseline.
 * Press or the  button to abort the current Line command.
 * By picking an existing edge with, instead of entering measurement points, the dimension will become parametric and remember which edge it is bound to. If the endpoints of that edge move later on, the dimension will follow them.

Properties

 * : The start point of the distance to measure
 * : The end point of the distance to measure
 * : A point through which the dimension line must pass
 * : Specifies if the text is aligned to the dimension lines or always faces the camera
 * : The size of the letters
 * : The size of the extension lines (between the measurement points and the dimension line)
 * : Can be used to force the text to be displayed at a certain position
 * : Specifies a text to display instead of the measurement. Use the word "dim", inside that text, to display the measurement
 * : The font to use to draw the text. It can be a font name, such as "Arial", a default style such as "sans", "serif" or "mono", or a family such as "Arial,Helvetica,sans" or a name with a style such as "Arial:Bold". If the given font is not found on the system, a generic one is used instead.

Scripting
The Dimension tool can by used in macros and from the python console by using the following functions:

makeDimension (p1,p2,[p3]) or makeDimension (object,i1,i2,p3) or makeDimension (objlist,indices,p3)
 * Creates a Dimension object with the dimension line passign through p3.
 * The Dimension object takes the Draft linewidth and color set in the command bar.
 * There are multiple ways to create a dimension, depending on the arguments you pass to it:
 * 1) (p1,p2,p3): creates a standard dimension from p1 to p2.
 * 2) (object,i1,i2,p3): creates a linked dimension to the given object, measuring the distance between its vertices indexed i1 and i2.
 * 3) (object,i1,mode,p3): creates a linked dimension to the given object, i1 is the index of the (curved) edge to measure, and mode is either "radius" or "diameter". Returns the newly created object.

makeAngularDimension (center,[angle1,angle2],p3)


 * creates an angular Dimension from the given center, with the given list of angles, passing through p3.
 * Returns the newly created object.

Example:

import FreeCAD,Draft p1 = FreeCAD.Vector(0,0,0) p2 = FreeCAD.Vector(1,1,0) p3 = FreeCAD.Vector(2,0,0) Draft.makeDimension(p1,p2,p3)

Links
Tutorial Projecting dimensions on a Drawing Page