Creating a surface element and cutting out a part of it

Entering polylines

You can use the polyline entry tools to quickly and easily create surface elements (e.g. hatching) and cut out parts thereof.

The following options are provided:

• In most cases, you can use Area detection together with Island detection: closed outlines within an area are detected and cut out automatically. To apply a surface element to the outline within the area, use Inverse island detection.
• You can enter the parts to be cut out separately using Multi and Minus.

To use area detection for creating a surface element and cutting out a part of it

1. After having selected a tool for entering an area (for example, hatching), click Single and Area detection in the Input Options.
2. Switch on Island detection.
3. Click in the area. Make sure that you do not click within the part you want to cut out.
4. Press ESC to quit the tool.

To create a surface element using the conventional approach

1. After having selected a tool for entering an area (for example, hatching), click Multi in the Input Options.
2. Enter the outline of the area to which you want to apply hatching.
3. Click Minus in the Input Options.
4. Enter the outline of the area you want to cut out and press ESC to finish.

   Note: If you enter the first point of the area to be cut out and you see the "You have already entered this polygon. Would you like to subtract it again?" message, check whether Area detection is selected in the input options for entering polylines.

Note: You can create areas composed of any number of polylines. Use Minus and Plus to define whether each new polygon is to be added to or subtracted from the overall area.
Example

Tip: To subtract an area from an existing surface element at a later stage, use the Reshape Surface Element, Architectural Area tool.