The Bézier Drawing Program began as an attempt to emulate something my daughter had been doing for a number of years, making Christmas cards and birthday cards using various geometrical constructions superimposed on each other, usually with a radial symmetry, to produce intricate and interesting designs. I decided to try to do the same thing on a computer, and began with standard shapes like hyperbolas, ellipses, polygons, and vaguely teardrop-like shapes, always enclosed upon each other so they could be filled with color. The emphasis was on being able to manipulate the objects with a mouse, clone the objects easily, and produce radial symmetry about a centre point. The original intent was to produce a monochrome wireframe display which could be printed at high resolution, and perhaps colored by hand after printing. Subsequently the following changes in scope were made :

• Library of objects was expanded to include some of the more complex closed-form shapes like cardioids and trochoids.
• Added support for a coloring operation which operates like a floodfill in a bitmap, with a color-picker.
• Added support for a zoom feature, for more precise positioning of objects.
• Added support for SVG output, to make it more web-compatible.
• The corollary to SVG output is that color-filling can be done using other programs, such as Inkscape, which use a completely different set of rules for filling objects: totally vector-based, not bitmap-based.

  The word Bézier is used in the program title because almost all the drawing is done using Bézier curves, the only exception being the occasional ellipse. The Bézier curves are spliced together in various ways to produce the desired object. These curves were chosen for two reasons: firstly, they are rendered extremely rapidly by the graphics engine, so it is possible to do live manipulation with a mouse; secondly, the standard vector graphics file formats such as SVG have full support for them. Since Bézier curves were used, the resulting shapes are not absolutely true 'hyperbolas' or 'trochoids'; however, in most cases you would be hard-pressed to tell the difference. If you detect a significant deviation from a 'true' shape, let me know and I'll investigate it to see if it can be fixed.

    The program is written in Visual Basic 6, and has no special installation procedures. However, the operating system should be newer than Windows 98, and you must set the color depth of your monitor to be 24-bit or higher, sometimes called 'True Color'. (Check the Display Properties under Color Quality.) If you encounter any problems running it, let me know, and I can probably email you the necessary support files. Also, try to keep the help (.chm) file in the same directory as the executable (.exe) file.

    To view an example of Bézier curves by Pierre himself, click here.

    This is a work in progress: if you have ideas for new features you would like to see, let me know, and I'll put them onto my list of things to do.

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