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Odamex dutifully follows the guidelines of the GNU General Public License (GPL). As a result, the Odamex source will always be available for everybody to download, observe and modify.

GPL Compatibility

Origins

Odamex is based on csDoom 0.62. This was, in turn, based on ZDoom 1.22). Fly, the author of csDoom, claimed that it was GPL; however, the ZDoom codebase which he used actually contained source code under several conflicting licenses:

• The Doom source under the Doom Educational License.
• QuakeWorld, which was released under the GNU General Public License.
• Heretic and Hexen code, which was released under a separate, GPL-incompatible license.

Unfortunately, it is not possible to have a proper GNU GPL port while the codebase contains code under a GPL-incompatible license.

Solution

Odamex has taken the following steps to ensure that it is compliant with the GPL:

• All code from ZDoom 1.22 that originates from Heretic or Hexen has either been completely removed or rewritten from scratch.
• Randy Heit has agreed to relicense his own code in this version of ZDoom under the GNU GPL, provided that the above condition is met.
• The fact that Doom is now available under both Doom Educational License and the GNU Public License grants the author of a doom port the right to choose either one (assuming there are no other conflicts to the GPL option).
• Fly's own code was provided with a GPL license, so we are taking this to mean that any of his contributions are licensed under the GNU GPL.

External Links

• Wikipedia entry on the GNU GPL
• GPL License v2
• Doom Educational License