3D House

From WFFwiki

Contents 1 Introduction 2 Where on earth is my house? 3 Drawing the 3D model 4 Landscaping

Introduction

I've always been fascinated by Google Earth and satellite imagery in general. In December of 2008 my daughter and I came up with the idea of taking pictures of our street and the surrounding area so we could geo-tag them and submit them to Google Earth.

I really liked the 3D models that were available and decided that it would be an interesting project to try and produce a model of my house. I guess it's not too difficult to produce an approximate model, but I wanted to get it as accurate as possible.

Where on earth is my house?

Well, the first problem with creating a model of the house is knowing exactly where it is and in what direction it is facing. This is not as simple as you might think, GPS and Google earth aren't exactly accurate. The first thing I did was to dig through the documentation I got when I brought the house, in the pile of papers I found a 'Tomtägaren' from 1946 which is a record of the land registration. This was made over 10 years before the house was built (in 1961) and contained a survey map of the land. In the lower left-hand corner of the map are some coordinates which (I think) are in Swedish RT38 national grid format and completely useless since they cannot be accurately mapped into modern GPS coordinates. However, by performing a little maths on them I was able to accurately reproduce the map in Visio.

The most useful thing about this was the ability to then calculate the orientation of the house's front wall, since it was parallel to the front land boundary. We are 30.8 degrees east of true north.

Once I had that done it was a laborious case of measuring everything and producing visio diagrams of the house from all aspects and on both floors. I've included a couple of the diagrams here, but in all I made 11 diagrams showing everything I could measure.

Most of the measuring was done with a long measuring tape, string and a laser-level mounted on a tripod. I also had some old drawings of the house which I was able to approximate measurements from using a vernier caliper. Luckily I was doing this over the Christmas holidays which meant my good friend Richard was around to help (and he never questions me about why, since he knows the answer is 'because').

Drawing the 3D model

With all the measuring complete it was time to fire up Google Sketchup and begin drawing. Firstly I drew the ground floor and created holes where the windows and doors were to be fitted, in this I included 400mm of foundations to avoid the house 'floating' above the ground when placed in Google Earth:

Then I added the supporting concrete floor across the centre of the building:

After this I drew the upper floor and then fitted on the roof of the building:

I then added in the doors, windows and the chimney which completed all of the major features of the building:

In order to get the correct textures for the outside of the building I went around the house and took pictures of the various surfaces. I was even able to get a picture of the roof tiles (my house is 'in' a hill, so the ground floor at the back of the house is in fact on the upper floor of the house) by standing up on the hill in the garden. I used Photoshop to remove the perspective of the images and then tiled the result onto the correct surfaces. I also measured and modelled the balcony fence (which was very time consuming as it was a complex shape):

And here is the same model, but from the back of the house, you can see in this picture how much higher the back garden is in comparison to the front garden:

Landscaping

I have now measured the front-garden and the outside steps around the house and produced visio diagrams of them. I have yet to measure the back patio and garden; I was slowed down a bit due to a large amount of snow which makes it difficult to see the boundaries.

Here is a picture of a test model, which has the front garden and the steps at the side. The shape that the house is sitting on is the actual shape of the land taken from the land registration documents shown earlier:

That was all I had time for before going back to work in January. It was a lot more work than I imagined! I hope to find time soon to finish the front garden modelling and get on to the back garden.