6. GEOMETRY

An inkprint geometrical drawing is a set of dots, lines and shapes: the figure, accompanied by identifiers like characters, and symbols like indicating a 90° angle etc.
Inkprint symbols are often graphical, in relief these might easily be mistaken for 'real' parts of the drawing: so I think they had better be replaced by braille code, or their meaning described, to avoid probably confusing images.
Take care your identifiers are unambiguous, make sure they point at one item only.
For ease in reading, draw lines belonging to different items or of different meaning in different widths, like a triangle fat-lined, the lines inside thin. Take special care of intersecting lines.

    Basic Editing in Geometry
    inkprint (ca 35K)
    braille (ca 80K)

In general, grid has to be copied, but don't let it get too fine-meshed, squares with sides smaller than 1½ cm make no sense, preferably go over 2cm. Use very thin or dotted lines for your grid. A very fine grid could either be simplified by rendering only the even lines, have the odd lines represented by a small dash on the axes only, or leave out the lines altogether, and put dots at the (imaginary) intersections. (Consult appendix Autocad on dotted lines and hatch: grid.)

    Fine Grid (ca 65K)
Some figures carry very small details: if necessary zoom in on a separate drawing.
For clarity, or even perceptibility, we sometimes have to make changes, overdoing distances etc.: just as long as we don't change its meaning.
Geometry graphics sometimes sport real-life elements: I prefer to edit those parts, as in general they're just there to brighten up the picture. Occasionally a formalized form with an explanation or a description will be necessary.
    Formalize (ca. 80K)
You may have seen these examples in earlier chapters:
    ball projected on screen (ca. 60K)
    winding road with distances given (ca. 50K)
    giraffe and kangaroo formalized (ca 170K)
This also applies to drawings showing tools like scissors, plastic triangles, rulers etc.: in general just mentioning their presence and describing their use makes more sense than trying to reproduce their outline.
    Drawing Tools for The Sighted (ca 65K)
Replace inkprint colors by our different hatches or linetypes; don't forget to have the text changed too.
In simple geometry open and filled dots sometimes have a specific meaning, so copy them in a perceptible way.

Spatial geometry, or in fact its twodimensional renderings, are very hard to the blind student, as a slanting line will not indicate a possible change of plane to him. I think a cube or pyramid are as far as we can go, and even in these our reader will need help, so I have a figure like these preceded (once in a volume) by a like figure with an explanation as which plane is in front, which on top etc.

    Orientation Cube (ca 65K)

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© 1989, 2002 Marco Schuffelen All rights reserved


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Last modified: Thu May 15 10:30:29 PDT 1989