Filtering

Importing a DWG File

Importing a DWG file into a CivilCAD project is typically the first step in building the project. You will import the file to use it as a working background or to extract various data, such as coordinates, as explained later in this chapter.

1. Open a New Project

2. From the main menu bar in ACAD, go to: File → Open.

3. In the window that opens, select the desired DWG file.

4. Save the project by selecting: File → Save.

5. After saving, CivilCAD will copy the selected file into the project directory and rename it to the project name with an added suffix _. From now on, every time you open the project, the software will automatically open the copied DWG file as well.

Note: If various actions have already been performed in the project, such as uploading survey points, creating contour lines, etc., this action will delete the layers that have already been created. In such a case, you will need to restore the project layers by clicking the Refresh button.

Filter (Extract) Points and Lines from a DWG File

CivilCAD needs the coordinate file of the existing state to create a 3D model. Often, this file is not available, and we only have a background file in DWG format. CivilCAD provides a convenient and efficient tool to "extract" elevation points from a DWG file:

1. Open a New Project and import a DWG file as explained at the beginning of the chapter (see - Importing a DWG File).

2. From the main menu bar, go to: General → Filtering. The filter window will open on the right with two lists: the drawing layers list and the entities list for selection.

3. Select the list where you want to filter the points by choosing Topography/Design.

4. In the drawing, locate the layer containing the survey points and identify the type of entity that characterizes them (Point, Block, etc.).

   Note: There may be multiple attributes for survey points such as Point and Text. You must identify the most precise entity (an entity of type Text, for example, is not in the exact location of the point but slightly shifted).

5. In the list on the right, select the layer and entity type chosen or click Select, select one of the shapes in the drawing representing the layer and entity type, and press ENTER. Using Select, the software will automatically highlight the layer and entity type in the list.

6. Click the Apply button. The software will now scan the selected layers and filter the survey points from them. At the end of the process, a list of survey points will appear in the bottom window (`Topography/Design → coordinates`).

7. Click Refresh, and the software will add the created point layers to the drawing.

8. If you want to filter a specific area in the drawing, click the Select inside window button in the window on the right, go to the drawing, and click on two corners representing the window where the software will scan the points.

From here, you can continue working as usual, including creating contour lines, etc.

Naming Filtered Points

If you filtered points from the drawing into a list and want to name the points based on a text layer containing names next to each point or based on a layer containing blocks with defined point names, follow these steps before clicking the Apply button in the Filtering window:

1. Click the Options button.

2. Check the box next to Set points names by layer.

3. From the dropdown list under Scan from layer, select the layer containing the names.

4. Next to Scan names radius, enter the maximum scan radius value.

   - The software will scan within the given radius for each point and search for text in the selected layer. If found, the software will use the text value as the point name.

5. If filtering blocks and the name is in the Block's Attribute, check the Attribute option and select the layer containing the Attribute under Scan from layer.

6. Click OK to exit the Options window and apply the point filtering by clicking Apply.

Setting Heights for Filtered Points

To filter points from the drawing into a list and set the heights of the points based on a text layer containing height labels next to each point or based on a layer containing blocks with defined point heights, follow these steps before clicking the Apply button in the Filtering window:

1. Click the Options button.

2. Check the box next to Set points height by layer.

3. From the dropdown list under Scan from layer, select the layer containing the height labels.

4. Next to Scan heights radius, enter the maximum scan radius value.

   - The software will scan within the given radius for each point and search for text in the selected layer. If found, the software will use the text value as the point height.

5. If filtering blocks and the height is in the Block's Attribute, check the Attribute option and select the layer containing the Attribute under Scan from layer.

6. Click OK to exit the Options window and apply the point filtering by clicking Apply.

Reducing the Number of Filtered Points

In situations where you want to filter a survey file consisting of many lines with numerous closely spaced points, CivilCAD will filter every point on the line. In heavy drawings, this action can burden the computer's processor and increase the file size. Therefore, you can reduce the number of these points by setting a minimum distance between points as follows:

1. After selecting the desired layers and line type (as explained in the previous sections), click the Options button in the Filtering window.

2. Check the box next to Reduce polyline points.

3. Enter the minimum distance between points that the software will filter (in meters) next to Minimum distance.

4. Click OK to exit the Options window and apply the point filtering by clicking Apply.