In a situation where precision is not essential, you can create a conceptual network by raising the level of basic points or make a stepped model using surfaces. In this lesson I will show you how to make a simple terrain model.

In order to create the base on which a specific object is located, we will use ArchiCAD’s Mesh tool, which you can find on the tool palette on the left side of the screen. When a new frame appears on the screen, you will see that there are different methods at your disposal to create such an element. The best solution is the so-called Solid Mesh because it can be subsequently shaped and accurately presented in orthogonal and 3D view. I’m going to go down a little bit and look for the option called Cover Fills because I’d like it to be active and the elements that make up the surface to be partially transparent. To that end, I will first confirm this option and then click on the field that represents the currently selected color and select the item named A-ED 25% from the list. After that, I can define in the same way the shade that will be used for drawing the lines (Cover Fill Pen), and it would not be bad if the background remained transparent, because that way you will be able to see what is happening under this element. In the section called Override Surface, you can choose the appropriate material, and I will choose the one that represents grass, although it is not of any great importance.

To simplify the whole process, I will choose an existing drawing as a reference. To that end, I will look for the Survey option in the Worksheets section and open the auxiliary menu by clicking the right mouse button. After that, I just need to select the Show as Trace Reference option so that the corresponding drawing appears on the screen.

Since I will use the existing contours for drawing and thus enter the exact dimensions, I can choose from this palette a method that involves drawing polygons (Polygonal Method), rectangles (Rectangular Method) or rotated rectangles (Rotated Rectangular Method). The final choice will depend on the complexity of the shape to be displayed, and if you are not sure that the terrain has the shape of a regular rectangle, it is best to choose the polygonal method.

Before I start drawing, I will zoom in on the appropriate detail and by pressing the right mouse button from the auxiliary menu, select the True Line Weight option so that all new lines have a certain thickness. After that, it won’t be difficult for me to use the mouse to locate the points that are at the opposite ends and thus limit my new network.

Now you can see that a new surface has appeared on the screen and that it is represented in light green. In order to highlight its display even better, you can temporarily turn off the drawing that is used as a reference, and this can be achieved by clicking on the icon located at the top of the screen.

Since drawing the internal contours is a long-term process, I will leave it for later and for now I will simply determine the height at which the corners and other characteristic points are located. To that end, it is necessary to first select the entire grid with one click, and if you have previously turned on the option for quick selection (Quick Selection Method), you can click anywhere on the surface that represents this object. In order to be able to see the data related to the height, I will turn on the view of the reference drawing again and then zoom in on the corresponding detail and immediately click on the point located at the very corner. After that, it is necessary to select the option from the palette that allows entering the Z coordinate and enter the appropriate numerical value in the frame that appeared on the screen. I will use millimeters as the unit instead of meters, which implies a thousand times greater value than 99730 mm. If you want the other points to be set at the same height, activate the Apply to All option, and since this is not the case for me, I will simply close this frame and move on to the next corner. If I select the appropriate point with the left button, the program will automatically activate the option to enter the Z coordinate, so it will not be difficult for me to enter its height, 98910 mm. Since I don’t know the height at which the third corner is located, I will add a new point with one click and then determine its height in the same way. In doing so, I will use the data relating to the entire line, which in this case is exactly 84500 mm. In a similar way, I can solve the problem that appeared on the upper edge, but before that I have to check at what height this line (86500) is located. After that, it will not be difficult for me to insert this data into the appropriate field and thus complete the entire procedure.

Since I am not sure that I hit the exact position of the reference point, I will first turn off the guidance function (Magnet) and then select the True Line Weight option to display the actual thickness of the line. If I then zoom in on this detail, I will be able to activate the Move Tool and finally correct my mistake.

Since I don’t know the exact height at which the last two points are located, I will have to find that information indirectly. This can be achieved most easily in 3D mode, so I will first select this element and then press the right mouse button and select Show Selection in 3D from the auxiliary menu. After that, I need to adjust the display scale by selecting the Fit to Window option and select the appropriate projection with Orbit.

As you can see, at this end the height of the grid is still very small, so I will first press the Esc key and then select this element and click on the corresponding point. After that, I need to activate the option to enter the Z coordinate and determine its new position with one click. In the same way, I will solve the problem that occurs at the fourth corner, and since I am not very satisfied with what I have achieved, I will once again select both points and move them to a height that fits better with the existing slope. Regardless of the fact that in this case I did not have the exact data, it can be said that the work was done successfully and that the entire network now occupies the correct position.

In this way, I completed the basic design of my terrain, although this element looks more like one big board. Now it is necessary to edit the space that is in the immediate surroundings, and in order to do that, I will turn off the display of the reference drawing and activate the option related to the field. After that, it is necessary to download the appropriate data from the existing element, so I will click on it while holding the Alt key and then draw a larger grid. In doing so, I will use the method that involves entering opposite points (Two Point Rectangular Method) and thus complete this part of the work.

According to the color used for covering, it is easy to determine where these elements overlap, so I will click on this grid and then select the option from the palette that allows me to remove a certain segment (Subtract from Polygon). If I then press the space bar and click on an edge belonging to another element, the program will automatically cut the corresponding segment and make a hole.

Since it is a 3D structure, it is necessary to select both elements and change the display by selecting the Show Selection in 3D option. After that, it will not be difficult for me to raise the points I just created to the appropriate level, and this can be achieved without changing the position, because in this case it is possible to see the other side of the model.

In this way, I first formed a hemmed pyramid, which means that I have completed half the work. Now I can continue and move the points on the outer edge in the same way. If after that I look at the whole structure from another angle, you will notice that it did not turn out very well, so I will use the opportunity to get a slightly more realistic picture with a few subsequent corrections. This task requires several steps, so I’ll change the view again and tweak the whole grid a bit more.

It seems to me that this will be quite enough, so I can return to the view of the complete terrain and finish this lesson.