[Blindmath] Announcing SVGExplore01 from the creator of SVGDraw01

[Richard Baldwin]

SVGExplore01 is a program designed to allow blind users to explore drawings
created using SVGDraw01 by using sound in conjunction with an embossed grid
system on a computer touchpad. This message describes a prototype "mouse"
version of the program.

Version 0.0.1 20111028
Table of contents

    Welcome to the prototype version of SVGExplore01
    This is a mouse version of the program
    User instructions
    This is not an SVG drawing
    Packaging
    Downloading and running the program
    Please provide feedback


Welcome to the prototype version of SVGExplore01

This is a prototype version of the program.

The program is posted at
http://www.austincc.edu/baldwin/SWT-SVG/SVGDraw01.zip and is available for
immediate downloading.

This program makes it possible for blind users to trace out the shapes in a
drawing by moving a finger on an embossed grid system while listening to
stereo sounds emitted by the program.

Audio hints are provided to help the user acquire the different shapes in a
drawing. Once the user has touched a location on the touchpad that
corresponds to the border of a shape, a series of stereo audio pulses makes
it possible for the user to trace out the shape with the finger on the
embossed grid.

My hope is that this will provide an economical "quick look" alternative to
the use of fully embossed drawings for the purpose of allowing the user to
form a mental image of the shapes in the drawing.

Each shape in the drawing emits pulses with a different audio frequency.
This is the mechanism by which the user can distinguish one shape in the
drawing from the other shapes in the drawing.


This is a mouse version of the program

A fully operational touchpad version of the program is still in development.
I am providing a mouse version at this time to allow potential users of the
program to get a taste of how it works. I am hopeful that those users will
try it out and provide feedback and suggestions for improvement.


User instructions

I will explain how to download and run the program later in this document.

In addition to a Windows computer with stereo speakers or headphones, you
will need a mouse and (optionally) a sheet of paper embossed with a
rectangular grid system. Emboss horizontal and vertical grid lines on the
paper at approximately one-half-inch intervals. If you don't have an
embosser, use a tracing wheel, a straight edge and an ice pick, or whatever
works for you to create tactile grid lines. It will probably work best if
you tape the grid paper to the tabletop to keep it from moving.

Start the program running using the instructions provided later in this
document.

Grasp the mouse in your right hand with your thumb touching the upper-left
corner of the grid. Try to hold the mouse so that the front-to-back axis of
the mouse is parallel to the left edge of the grid.

Press the 'h' key with your left hand. That will position the mouse pointer
in the upper-left corner of the drawing. Any time you feel lost you can
repeat that procedure to reposition the mouse pointer in the upper-left
corner to get your bearings again.

If you move the mouse to the right while dragging your thumb along the top
edge of the grid (or along any horizontal grid line), you will (sometimes)
hear a deep rumble in both ears similar to a motorcycle idling. Whenever you
hear that sound, it means that there is a shape somewhere along a vertical
line that is parallel to the left edge of the grid and below (or above) the
mouse pointer. Note that you will only hear sounds when the mouse pointer is
moving.

To acquire a shape with the mouse pointer (when you hear the motorcycle),
slowly move the mouse in a zig-zag pattern from the top of the grid towards
the bottom of the grid. Pay attention to the position of your thumb in the
grid system in order to identify the location of the shape.

When you have acquired the boundary of a shape with the mouse pointer, you
will hear a series of pulses with a frequency or pitch that is higher than
the motorcycle sound.

There are three pitches associated with each shape. In addition, the three
pitches associated with one shape are readily distinguishable from the three
pitches associated with each of the other shapes.

When you have placed the mouse pointer squarely on the center line of the
boundary of a shape, you will hear a series of pulses at a pitch that I will
refer to as the center pitch. When the mouse pointer is slightly below the
center line, you will hear a slightly higher pitch. This means that you
should slowly move the mouse toward the top of the grid to place the mouse
pointer on the center line. When the mouse pointer is slightly above the
center line, you will hear a pitch that is slightly below the center pitch.
This means that you should slowly move the mouse toward the bottom of the
grid to put the pointer on the center line.

You will also hear the pulses in your left ear, your right ear, and evenly
in both ears. When the mouse pointer is positioned squarely on the center
line, you should hear the pulses with equal intensity at the center pitch in
both ears. If you hear the sound in your left ear only, you need to move the
mouse slowly to the left in order to place the mouse pointer on the center
line. Similarly, if you hear the pulses in your right ear only, you need to
move the mouse slowly to the right to acquire the center line.

Once you acquire the center line of the boundary of a shape with the mouse
pointer, your task is to move the mouse on the grid in such a way as to
follow the boundary of the shape that you have acquired, while feeling the
embossed grid with your thumb to form a mental image of the geometry of the
shape. As you move along the boundary, use the pitch variations and stereo
variations to keep the mouse pointer centered on the center line of the
boundary.

In order to help you maintain your orientation, all shapes are forced to be
closed, even if they weren't originally closed when the drawing was created
in SVGDraw01. By this I mean, for example, that if you plot a series of
points using the Polyline action in SVGDraw01, a line will be drawn that
automatically connects the last point back to the first point in this
program. That will help you to identify the ends of a curve and avoid
falling off the end of a curve only to search in vain for the rest of the
curve.

On the other hand, this is not completely without its problems. The return
stroke can sometimes cross the curve and create a crossroads where there is
no difference in the pitch of each of the four directions of travel at the
intersection. (Think of the center of a figure 8.) I'm still thinking about
how to solve this problem and suggestions are welcome.


This is not an SVG drawing

This prototype version does not make it possible to explore an actual SVG
drawing. Instead, this prototype draws the following four hard-coded shapes
for the purpose of giving you an opportunity to evaluate and provide
feedback on the process.

    A circle with a wide border near the upper-left corner.
    A rectangle with a very thin border in the lower-left quadrant.
    A clipped and rotated ellipse in the lower-right quadrant.
    A cubic Bezier S-shaped curve that begins in the lower-left corner and
ends in the upper-right corner. (Note that the return stroke on this shape
is a straight line from the upper-right corner to the lower-left corner that
crosses the Bezier curve near the center of the drawing. The curve and the
return stroke will sound the same so make sure to distinguish between them.)

The borders on the ellipse and the Bezier curve are thicker than the border
on the rectangle but not as thick as the border on the circle.

The overall drawing is a rectangle that is 1000 pixels wide and 700 pixels
high. Therefore, it should fit on most modern computer monitors

See how many of the shapes you can find and trace out with your mouse. In
doing so, try to keep the front-to-back axis of the mouse parallel to the
left side of the grid.


Packaging

As mentioned earlier, the program is posted at
http://www.austincc.edu/baldwin/SWT-SVG/SVGDraw01.zip and is available for
immediate downloading. I elected to encapsulate this program in the same zip
file with the program named SVGDraw01 in order to share libraries and
conserve disk and server space.


Downloading and running the program

Download and extract all of the material from the zip file into an empty
folder being careful to preserve the directory tree structure. Don't extract
into the root directory. One user has reported problems accessing the Help
file for the program named SVGDraw01 when the contents of the zip file were
extracted into the root folder.

Execute the file named RunSVGExplore01.bat to run the program named
SVGExplore01.

As before, execute the file named RunSVGDraw01.bat to run the program named
SVGDraw01.

As of the date of this writing, this document contains all of the Help
information that is available for the prototype version of SVGExplore01.


Please provide feedback

Please let me know if you find errors in these instructions, or you find
areas that deserve a more thorough explanation.

I would also like to know if there are features that you would like to see
added to this program, or hear suggestions for better ways to accomplish the
existing features.

Dick Baldwin
baldwin at dickbaldwin.com

-- 
Richard G. Baldwin (Dick Baldwin)
Home of Baldwin's on-line Java Tutorials
http://www.DickBaldwin.com

Professor of Computer Information Technology
Austin Community College
(512) 223-4758
mailto:Baldwin at DickBaldwin.com
http://www.austincc.edu/baldwin/