Trim

Performs a trim of a surface and retains specified regions of the surface while discarding others by projecting a curve on it.

How to use

1. Click the Trim icon or choose the Tools > Surfaces > Trim surface command.

2. The program console prompts Pick curve.

3. Pick the curve you want to be projected along a vector on the target surface. Once picked, the curve turns green.

4. The program console prompts Pick surface.

5. Pick the target surface to trim. The resulting trimmed surface turns magenta.

You have then the possibility to define the region to retain (see Loop Exterior in the Options list below).

The Construction Tree allows you to adjust any parameter in the tree at any time.

When a parameter changes, the trimmed surface will be updated accordingly.

Note: By default the curve is projected along both the curve normal and its opposite but you have several options to modify this (see Projection Direction in the Options list).

If you want to keep both the exterior and the interior regions determined by the projection of the curve, you can project the trim curve on the original surface twice: you will first keep the exterior regions, then the interior.

Options

Curve

To change the trim curve.

Views / Modeling Tool panel. Switch the Replace check button on and pick another profile curve in the scene. The trimmed surface will automatically be modified.

Surface

To change the target surface.

Views / Modeling Tool panel. Switch the Replace check button on and pick another surface to trim. Trimming will be automatically applied to the new selected surface.

Loop Exterior

To determine the area of the surface you want to keep

Modeling Tool panel. Switch on the chosen radio button to specify if you want to Keep exterior or to Trim exterior.

Projection direction

To determine the vector along which the curve will be projected.

Modeling Tool panel. Switch the chosen radio button on. You have the following options:

X axis. The curve is projected along the X-axis.

Y axis. The curve is projected along the Y-axis.

Z axis. The curve is projected along the Z-axis.

Current view. The curve is projected along the axis that is perpendicular (normal) to the current active view.

Curve normal. The curve is projected along its normal. In the following examples, the trim curve was translated along the x axis and placed in such a way to alternatively trim only one of the two halves of the target surface.

Inverse curve normal. The curve is projected to the opposite direction compared to the curve normal. The power to project the trim curve along the curve normal or its inverse gives the user the flexibility to trim a surface selectively.

Both curve normals. The curve is projected along both its normal and opposite direction.

Projection start point

Projection end point

To modify XYZ coordinates of the projection start and end points, therefore allowing you to determine a custom vector along which the curve will be projected.

Modeling Tool panel. Type the values in the XYZ data fields and confirm them by pressing Enter.

See also:

• PathCast to project a curve onto a surface in order to obtain a 3D curve on surface.

• Intersect to split surfaces along the curves resulting from the intersection between two surfaces. The output is a set of non-intersecting trimmed surfaces called faces.