Question: If you're working from pictures or illustrations and do not have accurate 'blueprints', how do you do it? Are there any tricks or techniques for reproducing a design by eye? In particular, how do you accurately capture proportions? Is it all just experience and guesswork?

For example, there are many designs in traditional Chinese construction that I just love, including many of the patterns on doors, windows and balustrades. But, not speaking Chinese, and not living within a convenient distance of a genuine Chinese temple, I have to rely on the Google Image:

(Some windows from a garden in Suzhou, the Zhuo Zheng Yuan)



Playing around, I was luckily able to figure out this first window by dividing a square up into 4x4 smaller squares and then cutting out a series of circles and ovals, although I'm still not sure if the proportions are right. (If you look closely at the image, you can see the circles and ovals; the blue glass is what's left. Compare with the next window, also found in the same garden.)



This gave a systematic and simple recipe for (mostly) reproducing the window design. Nifty.



This more box-like design has resisted analysis. I have an attempt in the right direction, but the proportions are definitely off; their inner panel is rectangular whereas mine is square, and I'm not sure "how" rectangular it is (i.e. the ratio of the sides.)

I would especially love to be able to decode the illustrations I've found in the old Yingzao Fashi, even if only approximately