Tech Tips

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How to Convert a 2D Block to a 3D Block

This Tech Tip Tutorial explains how to convert a 2D block (symbol) into a 3D block.

As an example, we have a 2D Road Stop Sign block that we want to convert into a 3D sign on top of a pole:

Exploding the block results in a collection of hatches, text and lines. We want to convert the text and hatches into polyface meshes so that the sign will be most efficiently rendered in 3D views and Render View.

1. Convert the text to a hatch.

In order to convert the 'STOP' text to polylines by exploding the text, select Tool Menu > Explode > Explode Text.

Hatch the interior of the text polylines text with a white colour. Note that the hatch auto-tracking will not work if the polylines do not form a closed boundary.

Separate the hatch from the polylines as in the image below.

2. Convert the hatches to polyface meshes.

The Tessellate function creates a polyface mesh using the current pen and layer, so make sure to set the pen and layer you want before running the function. You can use the Pick function to change Pen. Press T on the keyboard and then click on the hatch to pick the pen colour.

Tessellate a hatch by going to Draw Menu > Meshed Solids > Surfaces > Tesselate. You will be asked to indicate a hatch in the drawing and you can click on the hatch you want to tessellate.

A polyface mesh will be created from the hatch. Note that it may not be visible against the hatch if the current pen colour is the same as the hatch. Separate the Polyface Mesh from the hatch as shown in the image below:

3. Delete the original hatch and polylines.

4. Rearrange the polyface meshes to make a STOP sign

5. Rotate the polyface meshes 'upright' (from top plane to front plane).

in order to create a STOP sign that is upright in 'world coordinates' select the polyface meshes and set the DP to Top view.

Run the Modify > Rotate3D function.

Set the Rotation axis to DP X-Axis and enter an angle of 90 degrees. Now use the Point snap to indicate any point on the selection. The selected polyface meshes should have been rotated to face towards the Front view.

6. Add a 3D pole.

Draw a 3D mesh tube by running the Draw > Meshed Solids > Cone function.

Specify the Base radius and Top radius as 30mm (0.03m), and the height as 2000mm (2m).

Switch to Front View and set DP = front view. Then drag the STOP sign polymeshes so they are aligned to the top of the pole. Then switch to Top view and set DP = Top view.

Switch the DP snap off and drag the STOP sign polymeshes (which are now only visible edge-on and thus appear as a line) to the front side of the pole.

Switch to SW Iso view to check that everything looks correctly aligned.

Switch to Front view and go to Settings > View Settings > Render mode to Flat Shading.

    The STOP sign should look like the image below:

You can now save the drawing.

To view the sign in Render View right-click and select Render View from the menu.

Right-click again and select Render Settings. In the Render Settings dialog, change the Render Mode to Flat Shading and then click OK.

Now you can check whether the sign has been correctly positioned in front of the pole:

You can quit the Render View by pressing Escape.

7. Create a 3D block at the correct orientation.

We want the block we create to be oriented upright when we insert it into a drawing. This means that the pole will be oriented parallel to the drawing Z axis. Therefore, we need to create the block upright.

To do this set the view direction to SW Iso so you can see the STOP sign easily.

Select View Menu > View Direction > SW Isometric.

Then set the DP to Top View by selecting View Menu > Drawing Plane > Top.

Select the stop sign polyface meshes and the pole In the Properties Bar and make sure all selected entities are set to layer '0'.

Select Tools Menu > Blocks > Create Block from the menu. Enter a name for the block, such as 'STOP SIGN', and then click OK.

You will be prompted to indicate the base point of the block. Use point snap to indicate a point at the base of the pole.

Press Spacebar when prompted to indicate a clip rectangle.

Now when you insert the block you created into the drawing (Insert Menu > Block), it will be inserted perpendicular to the current DP.


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