These techniques make atmospheric lighting and bright light sources more realistic. For example, muzzle flashes, ion beams, and bright sunlight cause "glare" that obscures the outlines of intermediate objects and throws them into sharp silhouetted contrast.
Clay Fowler from TBG Software explains how HDR works.
A device's "dynamic range" is the difference between the darkest color it can display (or detect) and the brightest color it can display. Monitors have far less dynamic range than the human eye. Images displayed on our monitors, even in 32 bit color, only have 8 bits of precision for each color component (red, green, blue). That means there are only 256 levels of "brightness" possible on our screens! The human eye, in contrast, has either millions of levels of brightness or an infinite number of levels, depending on who you believe, but either way it's much greater than 256. When you stand outside and look through the trees at the sun, you're seeing some very dark colors in the shadows of the leaves all the way up to searing bright colors from the sun itself - a high RANGE of intensities.
Hence the graphic industry's quest for "High Dynamic Range" rendering. HDR is an attempt to render an image where the dynamic range is closer to the human eye's - so the bright parts of the image are really WAY brighter than the other parts, etc. As stated above, consumer grade video displays are only capable of rendering 256 different levels of brightness, so how can we really increase the dynamic range of that image on the monitor to attain this vaunted "High Dynamic Range?"
Of course, we can't. The hardware's not capable. But what we can do is this commonly used post-processing effect which the industry calls "High Dynamic Range Rendering":
- Render the scene to a floating point texture instead of to the screen. Colors in this texture have a truly High Dynamic Range (beyond the normal 0...1 range of normal textures, e.g. the sun can have an intensity of 2.0 or 3.0).
- Do a separable Gaussian blur on the bright regions of the float texture to obtain a "glow" map.
- Add the float texture and glow texture together (so now the glow has been added to each pixel).
- "Tone map" the "glowed", high range floating point texture back down into the normal 0...1 range. Tone mapping is a way to map the high range float values down into the normal 0...1 range for displayable textures (basically by decreasing the contrast of the darker parts of the scene and darkening those areas even more than they already are). There's no magic here - information IS LOST in the mapping, 'cuz we only have the normal 0...1 range of intensities to work with now. Tone mapping usually is as simple as saying newColor = original color to the power of 0.555 or some other fraction.
- Render this tone mapped texture to the screen as the final image.
For DropTeam, Pixel Shader 3.0 is not required for HDR to work. It runs even on low end NVidia 5200 cards and older Radeons (though it does hit performance on those older architectures, as ANY shaders do!)
- Play in a universe complete with a rich back story and detailed history.
- Realistic combat system that models projectile/armor penetration, various munition types, and interior vehicle damage in detail.
- Huge, detailed and varied alien landscapes each planet accurately modeling its own gravity and atmospheric density, radically changing the tactical situation.
- Map sizes up to a massive 1000 (!) square kilometers.
- Terrain height resolutions from small ridges and vehicle fighting positions to towering hills and mountains.
- Deformable terrain with engineering vehicles digging out trenches in real time, ordnance created surface cratering and even trees toppling over under artillery fire.
- Dynamic environmental effects include building destruction and vehicles exploding and flipping over.
- Game includes 20 scenarios plus a 10 mission single player campaign. New scenarios will be offered for download after the game's released plus you can create you own battles and share them with others.
- Up to 16 human players or more supported, depending on system specs. Maximum online players realistically only limited by game server bandwidth, CPU and RAM.
- Game launcher allows you to browse a list of servers that shows the servers’ current scenario, current number of players, game time remaining, and connect to the game sessions at will.
- Server management functions allow administrators to login and exercise special privileges on the server, such as kicking players and moving players between teams. This interface is within the GUI of the game itself.
- Various game types include "Capture the Flag" and "Objective" based missions.
MODDING AND EXPANDABILITY
- Highly extensible, open architecture makes the game easy to modify, even by non-programmers.
- Game uses XML (Extensible Markup Language) files for game objects. Allows for an incredible wealth of modding options and capabilities. All information about 3D models, physics, control mechanics is encapsulated and allows specification of any arbitrary texture data for terrains, skies, and models.
- Add new vehicles, change their physics, change turrets, swap one gun for another or put a brand new gun on a existing unit and more. All of this can be achieved by editing the associated the XML files. You can also create entirely new models and textures that weren't originally included. You can even just drop in your own 3D Studio models if you want!
- Game engine reads data from professional GIS (Geographic Information Systems) packages such as ArcGIS and Terragen. This is the same industry standard data formats that are used by the Department of Defense for simulations and by engineers for land work, surveying, etc...
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