BSP

This is v5.2 of BSP, the popular node builder for Doom.

BSP is maintained by Colin Phipps cph@moria.org.uk, though it is not actively developed.

What are Nodes?

Before you can play a Doom level that you have created, you must use a node builder to create the data that Doom will use to render the level. Doom uses a rendering algorithm based on a binary space partition, otherwise known as a BSP tree. This is stored in a data lump called NODES in the WAD file. This data structure must be precalculated and stored in the WAD file befor the level can be played; the tool that does this is called a node builder.

BSP is one of several node builders that can do this; BSP was the best known and most widely used node builder throughout the height of the Doom editing craze in the mid 1990s. There are others: idbsp is the original node builder that id Software used on the original Doom levels, for instance. ZenNode is also popular.

Features

• Fast Doom node builder.
• Supports a number of special effects.
• Supports multi-level WADs. Preserves non-level data in WADs.
• Includes an optional alternative algorithm for choosing the nodes which reduces the chance of visplane overflows.
• Optional support for compressing the blockmap.
• Compiles on DOS, Win32, Linux, UNIX.
• Supports big endian & 64-bit systems.

Getting BSP

The current releases of BSP are available at the BSP website.

For Linux and UNIX systems, you download and compile the BSP source code. See the included file INSTALL for instructions.

For DOS and Win32 systems, download bsp51.zip, which contains binaries for DOS and Win32 (that is, Windows 95/98/NT/ME/2000/XP). bsp.exe is the version for DOS (note: it requires the accompanying dos4gw.exe). bsp-w32.exe is the version for Win32. Note that I have not released BSP 5.2 on DOS/Windows, because there were no changes in this version that would affect the DOS/Windows release.

Usage

bsp [ -noreject ] [-factor nn ] [ -q ] [ -picknode { traditional | visplane } ] [ -blockmap { old | comp } ] inwad [ [ -o ] outwad ]

Where:

• -noreject Causes any existing REJECT lump in the WAD file not to be replaced.

• -factor nn Used for tuning the node builder. The number supplied is the weighting applied when a choice of nodeline requires other lines to be split. Increasing this value from the default of 17 will reduce the number of extra line splits, but this will generally cause a less balanced node tree. The default is usually fine.

• -q Causes BSP to run quietly, only printing output if there are errors or warnings.

• -picknode Determines the nodeline selection algorithm. The traditional option is best for most Doom levels. For levels which are intended for the original doom2.exe and suffer from some marginal visplane overflows, the visplane algorithm is designed to minimise these and may help in some cases. See the included visplane.txt for more information.

• -blockmap Selects the blockmap generation algorithm. The default old algorithm generates a simple and correct blockmap. The newer comp version produces a compressed blockmap, by reusing identical blocks which should be equivalent in actual use. The comp version is therefore better but it relatively untested so is not yet enabled by default.

• `inwad`` is the input WAD file. This may contain any number of levels and other lumps. The nodes and associated data resources will be built for every level in this WAD. Any other data present in the WAD will be copied to the output WAD unchanged.

• outwad is the output WAD file. If the output file already exists, BSP will write it's output to a temporary file while it is working, and will only overwrite the output file once it is finished. In particular, it is safe for outwad to be the same as inwad, although this is not recommended unless you keep other backups :-).

Either inwad or outwad can be pipes or special files. On most UNIX systems, you can have BSP read from STDIN and write to STDOUT by using it as follows: bsp -q /dev/stdin /dev/stdout

Special Effects

HOM-free transparent doors

Simply make the sector referenced by the doortracks have a sector tag of >= 900. No need to remember sector numbers and type them in on a command line -- just use any sector tag >= 900 to permanently mark the sector special. See TRANSDOR.WAD for an example of sector tags in the 900's being used to create

Precious lines:

If a linedef has a sector tag >= 900, then it is treated as "precious" and will not be split unless absolutely necessary. This is good to use around borders of deep water, invisible stairs, etc.

Furthermore, just for grins, if the linedef's tag is 999, then the sidedefs' x-offsets set an angle adjustment in degrees to be applied -- you can look straight at a wall, but it might come right at you on both sides and "stretch".

Copyright

Node builder for DOOM levels (c) 1998 Colin Reed, Lee Killough (c) 2001 Simon Howard (c) 2000,2001,2002,2006 Colin Phipps

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. See the file COPYING for details.

See the included file AUTHORS for a complete list of contributors.