# 21b: How does Fractint achieve its speed?

## Description

This article is from the Fractal FAQ, by Ermel Stepp stepp@muvms6.mu.wvnet.edu with numerous contributions by
others.

# 21b: How does Fractint achieve its speed?

Fractint's speed (such as it is) is due to a combination of:

1. Using fixed point math rather than floating point where possible (huge

improvement for non-coprocessor machine, small for 486's).

2. Exploiting symmetry of the fractal.

3. Detecting nearly repeating orbits, avoid useless iteration (e.g. repeatedly

iterating 0^2+0 etc. etc.).

4. Reducing computation by guessing solid areas (especially the "lake"

area).

5. Using hand-coded assembler in many places.

6. Obtaining both sin and cos from one 387 math coprocessor instruction.

7. Using good direct memory graphics writing in 256-color modes.

The first four are probably the most important. Some of these introduce

errors, usually quite acceptable.

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