Game Development Dictionary
|A generic term for graphics, sounds, maps, levels, models, and any other resources. Generally assets are compiled into large files. The file formats may be designed for fast loading by matching in-memory formats, or tight compressions for handheld games, or designed to otherwise help in-game use. It is often useful to have an asset tool chain. The original models may be high-density models with R8G8B8A8 images. You may have a model striper and image compresser that reduces the model for LOD, and compresses the texture to a DXT compressed image. These assets may then go through further transformations, and end up in the large resource file.|
|A form of a bounding box where the box is aligned to the axis therefore only two points in space are needed to define it. AABB's are much faster to use, and take up less memory, but are very limited in the sense that they can only be aligned to the axis.|
|A secondary surface where the current frame's graphics are stored before they are transferred to the primary display surface.|
|Because the polygons facing away from the viewer are not seen, and the extra time spent drawing them would have no effect on the visual quality of the scene, these backfaces are almost always removed in some manner.|
|See Backface Culling.|
|A curve that is generated from the creation of several control points.|
|See Bezier Surface.|
|A curved surface created from a mesh of control points.|
|Uses the four adjacent corners to interpolate the value of a pixel in a texture map. This decreases the jaggedness of a texture when it gets larger, but also takes more memory and gives it a blurred look.|
|When viewing a texture up close the texture becomes very aliased and ugly (for an example, in Doom get as close to a wall as possible). Bilinear Interpolation is the process of smoothing out the texture so that it is blurred and looks more smoothed when viewed up close.|
|A 2D image rotated in 3D so that its normal follows the normal of the viewing direction. Another definition would be: A 2D image that is rendered on the same plane as the viewing camera in a 3D world.|
|Usually a rectangular block of information where data is stored by the picture to make an image. For instance, if you capture the screen the data you would have is a bitmap of the screen.|
|An open-sourced 3D modeller released under the GPL. Blender was originally a commercial product, but was open-sourced when the parent company, Not a Number, folded. The Blender Foundation was formed by one of NaN's founders, with the intention of raising enough money to purchase the rights to make Blender open source, and met their goal within a matter of weeks. Blender is a powerful modeller, featuring built-in ray-trace renderer, NURBS curves and surfaces, Beziers curves and surfaces, powerful mesh modelling tools, meta-balls, skeletal animation and inverse kinematics, non-linear animation, sub-division surfaces, particle systems, etc... A Python interface allows for the creation of custom scripts for import/export, special effects, and so on. http://www.blender.org|
When an image is drawn so that images drawn before it can still be seen. This is done through blending the source colors with the destination colors at different percentages.
Also called Transparency.
|Bit Block Transfer (properly abbreviate BLT). The process of transferring a bitmap to or from a display surface via the blitter.|
|A highly specialized processor which is designed solely for working on graphics. * Usually adept at copying rectangular chunks of graphic data around from place to place. Since Operating Systems such as Windows, MacOS often deal with large rectangular chunks of stuff on a screen - such as, er, windows - a blitter has become a standard feature in today's graphics cards.|
|A method of outputting sprites by only showing non-transparent colors, without any checking during run time. This is done by precompiling a bmp into a piece of code that contains a set of screen memory writes that only include non-trasparent colors.|
|.BMP, a bitmap file format. Used as the standard file format for Windows, BMP files can display data through a number of different color depths, and is usually uncompressed. BMP format does include a Run-Length Encoding version for 8-bit files and does not support a 16-bit format.|
|Named after mathematician George Boole Boolean geometry refers to combining multiple objects. Common operations include "unions" which combine two shapes and "difference" operations. Difference operations can be used to cut one shape out of another. 3d Studio Max and the game Red Faction for the Playstation II are good examples of how Boolean geometry can be used in practical applications.|
|A box approximation of an object used for collision detection. An axis-aligned bounding box (AABB) is defined by the minimum and maximum 'x', 'y', and 'z' values. An oriented bounding box (OBB), however, generally gives a closer fit, because it is always aligned with the object.|
|An algorithm to compute which cells in a grid should be drawn in order to display a line between any two cells in the grid. Used to draw arbitrary lines to the screen.|
|Binary Space Partition Tree. This is a sorting method for sorting nonmoving polygons where polygons are either in front or behind the currently polygon. The resulting linked list gives you the proper sorting for all polygons on the screen.|
|A process of rendering polygons that gives them an illusion of depth.|
Refers to a modification to Heidmann's original stenciled shadow volumes technique generally attributed to John Carmack, although others came up with the same modification at about the same time. Rather than incrementing and decrementing for the front and back faces (respectively) when the depth test passes, the method increments for back faces and decrements for front faces when the depth test fails. This prevents shadow volumes from being clipped by the near plan, but introduces the problem of them being clipped by the far plane.
You can find out more about the algorithm here.
|The standard coordinate system. With three dimensions, there are three scalars, x, y, and z used to represent a point at a given distance from a reference point, the origin.|