DSM Sketching - How to use Cartesian, Polar and Base point aids

Polar or Cartesian dimensions used with Base point - Functionality summary

Examples of Polar or Cartesian used with Base Point

Procedure:

From within a sketch select a curve type, then there are 3 options:

The Sketch option panel > Dimensions ( feedback or input) is activated:

There are 3 options:

1. Create curves immediately
2. Select Cartesian or Polar option
3. Select Lock base point

Option 1: Create curves immediately:

Line

Select a start position > curve end, arc centre, grid position etc.

Enter length and angle, either to the 0 degree reference or relative to any preceded connected curve end.

Sweep Arc

For a sweep arc start position, references are made to either the 0 degree reference or relative to the preceded connected curve end.

Option 2: Select Cartesian or Polar dimensions: This permits an initial offset (optional) from a start position.

Example shows the Cartesian method:

A blue-coloured source target shows > select the initial start position for the selected curve.

Note: Shown below is how to start a curve from an existing curve end, select the start point twice, then select position for the curve end.

Option 3: Select Lock base point: This permits a persistent reference to a nominated position or to a curve start and end position.

Example shows the Cartesian method

Note this command can be used in two ways:

a) At the start of a new curve command placement: Select curve type, then in any order, Lock base point and either Cartesian or Polar > then select base point reference position, offset or 2nd select ( offset 0,0) reference position for curve start, then curve end position.

Shown is an offset start curve position from the locked base point.

b) During mid command

Shown is a base point commanded during the placement sequence of line curves.

The Lock base point can also be disabled during curve placement sequences and then enabled again. This allows for the continuation of curves being referenced from the preceding curve, then with enabling on again, the last curve end reference, becomes the new base point position.

Note to establish a new base point position that isn't on the connected chain, the current curve command must be stopped ( esc, esc, etc ) and then restarted by curve command and a Cartesian or Polar selection with base point enabled. The blue target should then be showing at cursor position: