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Half-Life and Worldcraft:
the new dynamic duo
By autolycus
I recently had the pleasure of visiting Valve to see how both Half-Life and Worldcraft 2.0 (which will only be available on the Half-Life CD) are progressing. In a word, both can be described as impressive, from both a player’s and a designer’s standpoint. The combination of Half-Life and Worldcraft 2.0 will add so much to your editing capabilities, you’ll wonder how you ever designed without them, or why, for that matter.

H A L F - L I F E ,   T H E   G A M E

Half-Life isn’t a simple TC with a few .QC hacks and new textures thrown in. Though Half-Life uses the Quake engine, it is clearly an entirely new game, thanks to some major technological enhancements made by Valve.

Monster AI

First and foremost, thanks to the programming wizardry of Steve ‘Wedge’ Bond, the monster AI presents you with a very life-like challenge. The grunts in this game will not blindly charge forward in a suicide run. They act as a group and seek cover, flank you, and (as is so often mentioned) will even throw grenades in your area if you try to hide. Certain bird like monsters will even act as a flock! This AI, compounded with the excellent atmospheric effects and the astounding creations of the level designers, will make single play mode an intriguing and suspenseful experience.

Skeletal Animation

Visually, one of the coolest new things in Half-Life is its monsters and their animation. The animation is a lot more realistic than its predecessors. In fact, it is one of the only games coming out that will be using the skeletal deformation style of animation. This will allow monsters to be more flexible in their movements and, at the same time, more complex in their construction.. For example, some monsters will even turn their head to look at you. As well, monster’s have some idle sequences programmed into them. On one sequence that I saw, the security guard, after standing around for a while, will scratch his butt with his gun. The way it works is the monster is formed of a skeleton around which is stretched a texture mesh. Moving around the "bones" of the skeleton will result in a more realistic animation than what has previously been seen. This will also prove most useful when making scripted sequences.

Scripted Sequences

Scripted sequences will definitely help add to the intrigue and suspense. I only had a chance to see a couple of them, but they were very cool. In one, you walk into an area just in time to see a security guard struggling to avoid getting pulled into an air duct. After a few moments of struggling, he gets pulled in. I suspect they’ll be adding gibs flying from the vent as well. Spooky. Another time, we walked into a room just in time to see the body of a scientist get pulled through a hole in the ceiling. Scary. These sequences will greatly add to the idea of a story unfolding as you play the game. Scripted sequences can be made by the user, although it is a rather complex situation. Right now, you must import the area into 3D Studio as a .DXF file, then animate the models as you like, then save it and include it in the game as an entity. This will hopefully be simplified to make it easier for the normal user.

H A L F - L I F E   D E S I G N

Designing with Half-Life and Worldcraft 2.0

Because Worldcraft 2.0 and Half-Life are so well integrated, designers will be able to take advantage of many of Half-Life’s most interesting features.


Path toolOne of the main things to consider in game design is how the monsters will be allowed to interact with the player. Worldcraft 2.0 will allow you to have some control over the monster AI. You will be able to control whether a monster is aggressive on sight, or if it will only attack once it is triggered or wounded. This opens up all kinds of gameplay options for single player mode. Also, setting up a monster’s path has never been easier, thanks to Worldcraft 2.0’s new path creation tool. Setting up a path is as simple as clicking and dragging the points until you have the complete path. Fill out a simple dialog box, and the names of the path_corners will be interpolated from there. (If you name the first path corner "grunt", the second one will be "grunt01" and so on). Note that this also works for func_train and anything else capable of following path_corners.


One of the many atmospheric effects introduced in Half-Life is the use of DSP (Digital Signal Processed) sound. In the previous generation of 3D games, you could design a metal corridor to look realistic, but one blast of the shotgun would pretty much ruin the effect. Now, using DSP, the shotgun blast will reverberate and echo as though you were actually in the corridor. This should greatly enhance the immersion of the player. Included currently are DSP entities for metal, tunnel, chamber, bright, water, concrete, big, and cavern sounds. Hopefully, there will be some way to create your own unique sounds for inclusion in user levels. To use DSP sounds in Worldcraft, you just place the entity in its location, set a radius and room type, and you’re done. This should allow for some eerie ambience.


 decals Decals and time-based effects will also heighten the atmosphere of the game. A decal allows you to "paste" a texture (of say, a map, message, moss, blood, etc.) to a wall. These can be set to appear only after a certain amount of time has passed. Levels are linked together dynamically, allowing the player to move back and forth through them at will. A player could return to a room from a previous level, only to find a message (the decal) from a scientist scrawled upon the wall.

16-bit Colored Lighting

Colored lighting is another hallmark of Half-Life. Available in either 16-bit software mode, or 24-bit with hardware acceleration, the colored lighting lends itself well to creating a believable atmosphere. The lighting effects are certainly not overdone, and when used, add something special. As an example, one level was in a state of alarm, and there were red flashing lights that looked fantastic. Because they can be seen by every player, you can use lighting effects, transparency, fog, etc. to create puzzles that are integral to the gameplay experience.

Creating colored lights is certainly not a difficult task either. Where you fill in the brightness value, you can include four values, ie: "255 255 0 500" for a bright yellow light (where the numbers correspond to red/green/blue/brightness).

Brush Attributes

Another of the impressive new features in Half-Life is the new attributes for materials. Brushes can be of different materials (glass, wood, metal, flesh, cinder block, and ceiling tile are the current choices). Also, they can be marked as non-solid, transparent, moveable, and breakable. You can even make them buoyant so they can float in water. All of these material types are very easy to use from within Worldcraft, usually taking no more effort than setting a flag in the entity properties, or picking something from a list box. Some entities, such as func_glass, are even pre-made.

One interesting feature you’ll be seeing in Half-Life is moving entities (such as doors) with transparent sections. Dave Riller, Valve level designer, explains: "If you want to make just a transparent brush, you can assign it (or a group of brushes) to an entity (like a func_wall) and assign the effect "transparent" to it, as well as how much effect to give (0 - 255). If you want a transparent pane of glass in a rotating door, you create two different doors basically. One which has the non-transparent brushes, and the other which shares the exact same settings, but has the transparent effect. We can link two door entities together so they never become desynched by, let's say a player, catching the door the right way and blocking one section."

Rotating objects are also handled much differently than in previous games. It now takes as little as two brushes to create a rotating object. The rotating assembly forms the first part, and a second brush acts as an axis around which the assembly will rotate. Various options can be set, such as acceleration, deceleration, plane of rotation, etc. Another big improvement is that these rotating assemblies are themselves solid, and do not require a secondary entity or brush to stand in as their solid form. This rotation also works when applied to trains and platforms. Half-life will allow both rotation and forward motion simultaneously, so they can curve, flip, and ascend along an irregular path. You can also set up platforms to behave like teeter-totters, so they tilt according to how close or far weight is applied from the fulcrum. This will definitely allow for some very unique design possibilities.

W O R L D C R A F T   2 . 0

Additional Worldcraft 2.0 features

Along with the new features already mentioned above, Worldcraft 2.0 enhancements will make level design much easier and quicker. A seemingly small option like being able to ignore object groupings actually allows you to save a great deal of time, in some cases. Imagine you have a complex shaped door made up of 20 brushes. Say you needed to modify a single brush in the door. Previously, this would mean having to ungroup the door, select the brush, modify it, re-select the 20 brushes, and re-group them. Now, you press the ignore group button, select the brush, modify it, and your done.

Entity ReportAnother fine addition to the Worldcraft "utility bag" is the entity report feature. At its most basic, it displays a complete list of all the entities contained in the level. More useful though is its ability to search through those entities and only display certain ones, depending on whatever search terms you’ve specified for the attributes and values, or classname. This will help when you’re trying to locate one errant entity that needs to have a target assigned, or an attribute value corrected. A nice touch here might be the ability to specify multiple search terms.

cordon toolMany other smaller features have been added as well. For testing specific areas of your level, the cordon feature has been added. This allows you to mark off a specific section of the level, then compile only that section. A solid box with the black texture will be placed around the cordoned area to prevent leaks. This is obviously very handy when you don’t want to wait for a full compile to test only a small section of the level. Also, the texture browser has been modified to give you the option to display only the currently used textures from the level. This will help you keep a consistent theme of textures running through your level, as well as making it easy to avoid using two similar textures by mistake. These new features and enhancements, as well as those mentioned throughout the article, will make Worldcraft one of the most versatile editors available.


The combination of Worldcraft and Half-Life is going to have a great impact on the editing community and the success of the game. After the initial use of a game, its add-ons and modifications are what keep it alive. Valve will be providing a game ripe with design possibilities, one of the most intuitive and powerful environment editors, and a CD full of editing information. This will let new users create relatively complex levels within a short period of time, and experienced designers will have the tools to jump right in. I am definitely looking forward to the Half-Life release.

Note: this article was written before it was announced that the release of Half-Life would be delayed. For what it's worth, I applaud Valve for delaying the release rather than cutting out features. This is definitely going to be one of the top games in the next batch of 3D first person shooters.

autolycus is the webmaster of The Forge, along with Loki. The site contains all the information you need to know to start editing Quake levels with Worldcraft, as well as other useful general editing information. Definitely worth a look if you're designing levels.

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