By Martin Phelps
Please note this may not be the only method to carry out this process, however this procedure works reasonably well.
Make sure that the “Google Maps” image is 2D.
Find the required location in Google maps, as Figure 1.
The area shown in this example is Junction 6 of the M5. The potential area to be developed is the lower right field below the motorway roundabout as shown in Figure 2.
Right mouse click to display the menu in Google maps select “Measure Distance” as in Figure 3.
Using “Measure Distance” place a dimension on the display, for example use an object with a known length i.e. the width of a road, or single carriageway of a motorway is approximately 10m or the know length of a wall of a building, etc.
Note: - This will be part of the screen grab image.
Make sure that the area required is displayed on screen.
“Screen Grab” the view, for example, in the case of most laptops to screen grab the display press “FM + PRT SC”.
Open an image edit programme i.e. “Paint” or “Photo shop”, start a new file press “Ctrl + V” to paste the screen grab into the new file.
Using the image editing software to “Crop” the image as required, as shown in Figure 4.
Once “Cropped,” save the image as a suitable format i.e. JPEG (*.jpg) and to a suitable hard drive location.
In the Revit Project working on “Level 0” or the equivalent level, draw “Model Lines” or “Reference Lines” to represent the boundary lines of the site.
In the “Project Browser” change the “Floor Plan” to “Site”.
Select the “Image” command from the “Insert” tab on the “Ribbon” menu to import the saved image.
Place the “Image” anywhere in the “Site” view. The “Image” now requires “Rotating” and “Scaling” to suit the model.
It may be better to first “Rotate” the image, so that the previously defined dimension is horizontal.
Draw to model lines from the approximate centres of the dimension points as shown in Figure 5.
Offset the line on the dimension shown to the true dimension as shown in Figure 6.
Select the “Image” and then the “Scale” command to rescale the image. Select the end point on the first line on the left, then the end point on the next line to the right and finally the line furthest to the right, this will rescale the image to as near a possible to the full size.
Roll the scroll wheel to “Zoom” out to see the result, as per Figure 7.
The map image is now scaled as near as possible to the size of the building.
Note: - Important do not “Move” or “Rotate” the Revit model, “Move” and “Rotate” the image to suit the model.
Use the “Reference Lines” previously created that represent the plot boundary to line up the site boundaries with the boundaries in the map, as shown in Figure 8.
Delete or Hide in view objects not required in the display i.e. dimensions and construction lines, as per Figure 9.
Note: - This is only an approximation and the accuracy will depend on the points and measurements specified by the user.
Change the “Display Style” to “Realistic” and “Hide” both the “Project Origin Point” and “Survey Point” as shown in Figure 10.
This is not lining the proposed building with real work co-ordinates, it’s showing the proposed building in relation to existing roads etc.