Developer commentary/Half-Life 2: Lost Coast

	This is a quote article.
	This article is a transcript of all of the quotes from a given character or entity. Unless noted otherwise, these transcripts are sourced directly from the official scripts, closed captions, or internal text data with only minimal modifications for typos and formatting purposes.

The following is a list of all of the developer commentary from Half-Life 2: Lost Coast's commentary mode.

Commentary

Filename	Speaker	Subtitle
comm_beach	Viktor Antonov	When the art team started to think about a location that would demonstrate the power of HDR, a beach was one of the first choices we made. The visual relationship between the sky, the water, and the rocks is something we could not achieve without HDR. In order for high dynamic range to correctly simulate the light's interaction with the surfaces around you, like these wet rocks, we needed more precise information about the surfaces than we've had in the past. So now, going forward, we're modelling textures in 3D packages to ensure that the physical information encoded in the texture allows HDR to correctly bounce light off the surface. We also design the colors and values of each surface to ensure they will be correct across all exposure levels.
comm_character	Randy Lundeen	The process of building characters in Half-Life 2 taught us many things. By the end, we believed we'd figured out a more effective process for designing and constructing characters. This fisherman is the first character we've built using that process. Design-wise, the fisherman was focused on showcasing HDR, and the way light falls on human skin. The highlights on his forehead and nose are good examples of specularity on human skin. You can see how the wrinkles on his cheeks, and around his eyes, are an example of how we can use normal maps to add depth. Production-wise, the fisherman was built using a similar process to the rocks you saw on the beach. We model the 3D character at a very high detail, then extract much of the physical information and store it in the textures.
comm_cliffside	Robin Walker	The area you're currently entering is called the cliffside arena. We were particularly happy with the vertical cliffside in Half-Life 1, and regretted that we didn't iterate further on that concept in Half-Life 2. Vertical space allows us to force the player to deal with threats from above and below. We find that players focus their view on the direction they're travelling, so by using a cliffside, and having the player ascend it, we ensure the player will look up and be prepared for enemies. If the player's path was to move past the bottom of the cliffside, it would be unlikely he would notice the soldiers rappelling down from above. Dying from unknown threats never feels fair, and certainly isn't fun.
comm_courtyard	Robin Walker	The courtyard in front of you is a space we call an Arena. Arenas are built to hold the player for a period of time, and usually contain combat or some other challenge. They often have multiple entry-points for enemies, along with a gate of some kind to prevent the player moving on, until the challenge has been completed. In this case, the arena is free of enemies until the player solves a puzzle, and triggers an alarm. This is a method that allows the player to explore the arena, and get a sense of its space before being forced to fight in it. It adds a sense of uneasiness to the player, who's expecting to be attacked now that they've reached the goal set for them at the start of the map. The break in action here is also a crucial part of the level's pacing. It allows the player to recover and explore the world a little, after being attacked on the way up the cliffside.
comm_hdr	Gary McTaggart	With conventional rendering, seen here on the left, if something on the screen is 20% reflective, like the wet sand, then the maximum reflected brightness could only be 20% of the maximum brightness of your monitor. HDR's more accurate simulation of light ensures that the sun's reflection on this wet sand appears as it would in the real world, which could potentially use 100% of the maximum monitor brightness. HDR uses bloom to simulate light that is beyond 100% of a monitor's maximum brightness.
comm_intro	Gabe Newell	Welcome to the Lost Coast. In this tour, we're going to be talking about a new graphics technology we've been developing, called High Dynamic Range Lighting, or HDR. We'll also be giving you some insight into the design and production challenges we faced during the construction of the Lost Coast. First, a quick explanation of the commentary system. To listen to a commentary node, put your crosshair over the floating commentary symbol and press the +USE key. To stop the commentary, put your crosshair over the rotating node and press your +USE key again. Some commentary nodes may take control of the game for the purpose of showing something to you. In these cases, simply pressing your +USE key will stop the commentary.
comm_intro_nohdr	Gabe Newell	Welcome to the Lost Coast. In this tour, we'll be talking about a new graphics technology we've been developing, called High Dynamic Range, or HDR for short. We'll also be giving you some insight into the design and production challenges we faced during the construction of the Lost Coast. It appears that you either have HDR disabled, or your video hardware does not support HDR. You're still welcome to take a look around the level. First, a quick explanation of the commentary system. To listen to a commentary node, put your crosshair over the floating lambda symbol and press your use key. To stop a commentary node, put your crosshair over the rotating node and press the use key again. Some commentary nodes may take control of the game for the purpose of showing something to you. In these cases, simply pressing your use key again will stop the commentary.
comm_monastery01	Viktor Antonov	We wanted to transition from a bright, wide-open space into a tighter, closed one to showcase HDR’s dynamic tonemapping. We also like to focus on contrasting elements in our settings, like ancient human architecture and futuristic combine technology. A monastery fit these requirements perfectly. Monastery's are generally isolated, unlit, and built ages ago. They provide a great backdrop for the contrasting combine technology. When we build fictional settings, we try to ground them by basing them off a real-world location. We use this location as a design constraint that forces a logical consistency behind the art choices.
comm_monastery02	Viktor Antonov	Churches are great dramatic spaces. They’re often lit naturally, with extremes of darkness and brightness, which makes them a great showcase for HDR. Gothic churches are the sober, monochromatic spaces that you’ve seen in almost every horror movie or game. Byzantine churches, on the other hand, are very colourful and have a large variety of materials. We wanted that color & material variety to show off our HDR reflections.
comm_normal (unused)	Randy Lundeen	The rock texture is an example of using normal maps. Our texture artists in the past have just had to be illustrators, mainly use Photoshop, painted the textures by hand, or use photographic reference. But what we're finding now is we're moving into next-generation content we want to have them also have the ability to model the texture in three-dimensions. So, they'll often use a package like XSI to actually build geometry for these rocks. So the normal map is basically taking a high-res, 3D model and rendering that onto a 2D surface. This way we can create the illusion of an object having much higher polycount than it actually does. So, for instance for these rocks, it's completely flat surface, but the normal map is creating the illusion of them bumping up out of the sand.
comm_puzzle	Robin Walker	Our games are filled with things we call “gates”, which are essentially just challenges that the player must overcome to drive the experience forward. We used a puzzle here, since the player has been through combat and exploration recently. When we design challenges, we try to ensure that the player’s goal and the action required by the player are both fun. It’s not hard to create interesting goals for the player, like stopping this machine from shelling the nearby village. But the action required by the player to solve the challenge needs to be fun as well. So instead of something menial, such as hitting an off switch, the player gets to use physics to jam the gun’s mechanism and cause it to break.
comm_shader	Chris Green	The Source engine supports a wide variety of shaders. The refraction shader on the window here requires us to copy the scene to a texture, refract it, and then apply it the window surface. To fully support HDR, every shader in the engine needed to be updated, so this refraction shader was improved to the support the full range of contrast.
comm_shipnode	Robin Walker	The remains of the ship in front of you were once part of a puzzle we cut out of the Lost Coast. The original design of the puzzle was based on the idea of the player and the fisherman co-operating together to solve something. This was a type of puzzle we’d always wanted to attempt in HL2. Unfortunately, as development on Lost Coast neared the end, and this puzzle still wasn’t finished, we decided to cut it. It’s always painful to remove work, so we’ve tried to evolve a process for making those kinds of decisions. For example, with this puzzle we asked ourselves 'Is this puzzle actually fun?', 'If not, how much work does it need to be fun?', 'Does this puzzle fit within the purpose of Lost Coast?', 'Would our customers appreciate this puzzle being finished more than they would appreciate, say, soldiers rappelling off the cliffside?'. In the end, it made the most sense to put this problem on the shelf with other interesting ideas, and come back to it later.
comm_tone	Chris Green	One of the features of our HDR solution is dynamic tonemapping. The easiest way to think about dynamic tonemapping is that it is a method of simulating the way the human eye reacts to light. In the real world, you’ve probably walked into a dark room and noticed your eye adjusting to the darkness, letting your see better after some time. Or you’ve walked out into a bright day, and been blinded by the sun, only to have your eye adjust and allow you to see normally. Your iris is adjusting itself in response to the amount of light hitting your eye. Dynamic tonemapping simulates this, by automatically adjusting the exposure of the scene to mimic the behavior of your iris. You can see this as the view moves from the dark tunnel to the bright sun, and back again. Here you can see the way we calculate the amount of light hitting the player’s eyes. We take a snapshot of the scene, and extract the brightness levels to get the average level of light. Additionally, we consider light at the center of the screen more important than that at the edges, to better simulate the geometry of the eye.
comm_water	Gary McTaggart	Water presents us with a lot of rendering challenges. In fact, we have to render the scene 3 times. Once for the refraction of what’s under the water, once for the reflection of everything above the water, and once from the player’s view. You can see the reflection & refraction scenes in the two small windows onscreen. In the refraction, we calculate, per-pixel, how much water you’re looking through to do a volumetric underwater fog, to simulate particulate matter. For our full HDR solution, we had to go through the entire engine and modify every bit of code that calculated light and color. For example, these water reflection & refraction renderings had to be improved to support the full range of contrast values.
comm_outro	Gabe Newell	This marks the end of the Lost Coast tour. This has been an experiment on our part to see if our community would find it interesting to learn more about our development process. As always, we're interested your feedback. I can be reached at gaben@valvesoftware.com. If people like this, we’ll keep producing this kind of content for all of our games going forward. Thanks for listening!

List of speakers

• Gabe Newell
• Viktor Antonov
• Randy Lundeen
• Robin Walker
• Gary McTaggart
• Chris Green