Tutorial 14a: Basic polygonal modeling

To access the tutorials in CityEngine, click Help > Download Tutorials and Examples.... After choosing a tutorial or example, the project is automatically downloaded and added to your workspace.

Part 1 : Polygonal Modeling

In this tutorial we will make a simple house using the polygonal modeling tools.

  1. In the navigtator, double click on 14A_Basic_1.cej from the tutorial folder to open the initial project.
  2. Select the Polygonal Shape Creation tool.
    Image before Polygonal Shape Creation
  3. Click in the viewport to set the first point on the bottom left corner of the white outline.
  4. Move the mouse to preview the line.
  5. Dashed orange lines appear when snapped.
  6. Find the snapping line to the top, and click on the top left point of the outline.
    Polygonal Shape Creation applied
  7. Move the mouse, and find the 90 degree snapping line.
  8. A small arc appears between the current and the previous line for this snap.
  9. Click to set the third point.
  10. Do the same for the fourth point.
    Setting fourth point
  11. Follow the shape outline, and click to set the fifth point.
  12. For the last point, find the intersection between the parallel snapping line (shown with small parallel signs) and the 90 degree snapping line from the first point.
    Final point set with intersection
  13. Click on the first point again to finish the shape.
  14. To create a 3D house, hover over the polygon.
    Push Pull tool activated
  15. Click the orange handle and hold the mouse. Drag up the orange handle.
    Extruded polygon
  16. Split of the back section: hover over the edge, click, go for the parallel snap combined with the edge snap, and click again.
    Split the top face
  17. Hover over the polygon, and drag it up.
    Extruded top face
  18. To create the roof, split the front polygon (polygon) like the last one. Then, hover over the edge. An orange handle appears. Drag it up, until you snap to the polygon.
    Split second top face
  19. To pull the roof out, first select the Rectangular Shape Creation tool. Snap to the corner, click, snap to the edge and click again.
    Extruded edge on 2nd top face
  20. Then drag out this polygon. Depending on what roof you want, you can drag along the green or the blue arrow. Use the blue for now.
    Extended roof face
  21. To create a garage, first draw a rectangle. Then drag it out.
    Create garage
  22. Draw another rectangle, drag it inwards a bit.
    Create garage door
  23. Now, create a door: draw a rectangle and drag it in.
    Create front door
  24. Rotate the camera to view the house from above. Click on the corner, and follow the snapline until the snapline from the top appears.
    Rotated to top view
  25. Click and then click on the other corner to finish the polygon.
    Split roof

Part 2: Texturing

The shape is now finished, let us texture it. You can continue with your scene, or alternatively open the reference 14A_Basic_2.cej.

  1. Click the selection tool, and then click on the house.
    Select house
  2. Open the texturing tool. Click browse, and select the wall_stones texture.
  3. You can find it in the asset folder of the tutorial.
    Brick texture dialog
  4. Double click to open. For a uniform texturing, select mode-dimensions and assign. To make the bricks smaller, set width and height to 10.
    Modifiy brick texture
  5. Now select all roofs. Double click on the first polygon, then hold control and click on the other ones.
    Roofs selected
  6. Browse for the roof texture and click assign.
  7. For the door, pick the door texture. Set the mode to stretch to polygon, to make the texture fit the door, and click assign.
    Texture roof
  8. Do the same for the garage, with the garage texture. The house is now completely finished.
    Texture garage door
    Note:

    You can still drag all faces and edges. The texture automatically adapts to new dimensions.