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Xara Home Construction Kit

We are now in a position to take a house plan and create a 3D view. I have used two files - one for the elevations and the other for the plan and picture.

Creating plan and elevations

Prepare a plan of the house to scale, sized to fit your picture at the angle you want (not too shallow an angle or one of the main vanishing points will be a long way from the picture). If you already have a front elevation set it to the same scale and line it up underneath. If you don't have one don't worry - I didn't. Use vertical guides to mark any positions on the plan of significance. Underneath the plan, construct your front view from these positions. You can measure the heights of your windows and doors and make a good stab at the floor and roof heights. Make sure the heights are in proportion to the widths.

You can easily make an end elevation. Clone and rotate your house plan by 90 degrees and move it to one side. Drop vertical guides as you did for the front and set horizontal ones from the front elevation. You will only need to do this for parts of the end that will be visible.

Now you can fill in your two elevations. Consider and group each flat surface independently. In the case of my own plan that meant the main front wall and gables, the slightly recessed front door wall, the further recessed alcove above and the front porch, not forgetting chimneys and roof. Repeat the procedure for the side elevation. If you are filling your surfaces with bricks you will need to make the heights and edges match. In my case I prepared a large area of bricks adjacent to the elevations and grouped them. Then I cloned the outlines of the elevations' brick surfaces, nudged them across (thus maintaining vertical positions) and used arrange/combine/slice shapes to cut out what I needed (not very well!). Now all that remains is to assemble the picture.

Creating the picture

Open a copy of the grid template file saved on Page 3 or create a similar one with your desired horizon, angle of view etc. Copy over your house plan and angle it on the plan grid; it simplifies matters if one corner touches the front (bottom) of the grid). Copy the front and side elevation sections you have prepared and paste them onto the outer margin (resize this margin with page options if necessary), on a new layer. (Exit the previous drawing and save it in case of rework). Draw an empty rectangle exactly round the plan grid and group this with a clone of the angled plan. With the mould tool apply a default floor perspective and resize the mould and its vanishing point to exactly fit the foreshortened grid, just as you did on Page 3. Now create the two vanishing points for your building. Carefully draw a line along one of the main front faces of the building and extend it until it crosses the horizon. Repeat with one of the end faces to get the other vanishing point. If you have, say, an angled bay window you'll have more lines to project and more vp's

Back on the new layer, copy the most significant surface from the front or side elevation and apply a right or left perspective (in my case, left). Align the front edge with its point on the floor plan, squeeze until the other edge lines up horizontally with its end on the plan and finally draw its vanishing point out to line up with the picture's vanishing point. If the front edge lines up with the front of the plan you shouldn't have to make adjustments to the height. If it doesn't you will need to reduce its height using Alberti's method explained on Page 4.

Once you have the first surface in place you can add the others in the same way. Adjust their heights so that they line up with the adjacent surfaces already in place, squeeze their widths to fit the plan as on Page 4, then use Ctrl-Shift b to move them backwards to their correct position in the stack. You could go on to add window ledges, etc. When you place the chimney stack you will need to convert to editable shapes and cut off the part obscured by the roof.

When complete, pick out surfaces in shadow and cover with a black shape set to 50% brightness transparency. In the final illustration on the front, the left gable roof looked odd, perhaps Leonardo's effect was kicking in, so I adjusted it by eye. Finally add sky and trim the borders.

If you wanted to, you could replace the windows with cut-outs and develop the surfaces behind them from the plan, using an additional layer for convenience.

Having created the elevation sections, you can always adjust viewing angle, viewing height or field of vision and so place these same elements in a different picture.

Questions? Comments? Criticisms? Please use the form on the next page to send me your comments.

Suggested reading:

Alison Cole, Perspective 1992, Dorling Kindersley

Charts the development of perspective techniques in painting through the ages with examples of the masters, and includes a summary of the principles.

John Montagu Basic Perspective Drawing 3rd Ed 1998 John Wiley & Sons

A comprehensive compendium of perspective techniques from simple to complex, all clearly illustrated with pen and ink sketches. If there is one book on the subject for the artist, this is it.