Measurements and Their Relationship to CG - An Introduction to Computer Graphics for Artists - page 58

Fig. 4.11 A caliper, compass, protractor , ruler, and triangle

objects, whose plans are often a matter of public record. If you cannot fi nd
dimensioned drawings, and quite often this will be true, the next best thing is a
group of orthographic photographs, particularly if combined with a known
measurement of something in the scene. Sometimes you will fi nd drawings of your
subject, but no photographs. These may be better than photos because they usually
contain structural information that would otherwise be obscured by a photo. A draw-
ing, if it is not dimensioned, or if it is not drawn to scale, is always subject to
interpretation. If you must work from this sort of reference, the degree to which you
are sensitive to dimensions will determine your success.
Large projects, such as the environment models in the movie The Avengers
(2012) involve costly and time-consuming reference gathering expeditions (Sumner
2012 ). For that film, a team was sent to New York City to secure permission
to gather reference from a group of previously identifi ed buildings. After the per-
missions were received, equipment was rented for use in reference gathering, such
as cherry-picker cranes that were used to photograph locations from a height of
20 ft, and then a group of artists was sent to the city to gather reference.
The expedition took more than a month to complete, and after it was over, the
255,000 photographs and measurements they gathered had to be organized. The cost
of gathering reference and taking measurements on that scale can exceed the total
budget for smaller projects, like the development budget for a video game. This
means that CG artists must often make do with less than perfect reference, or an
incomplete set of measurements. To get acceptable fi t for use results despite this
limitation, it is particularly important to develop sensitivity to dimensions. This will
improve your ability to estimate missing information. You can do this by getting
into the habit of measuring things when you can, or taking note of dimension