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Written by: David "Spunk" Grampa - January 30, 2000
Last updated by: Dan "Tweak Monkey" Kennedy - December 13, 2002
If you think of any terms to add to this dictionary, please e-mail us!
Charisma Engine - Culling
Charisma Engine - ATI's geometry processor is nicknamed "Charisma Engine", and was introduced with the Radeon 256 line. It offers a fast T&L engine, "Keyframe Interpolation", and advanced vertex skinning. Keyframe interpolation (or vertex morphing) is the name of the technology that allows for smooth transitions between frames (or the smooth morphing of vertices).
Clock Cycle - A clock cycle is one operation done by a microprocessor in which electricity goes through a processor turning transistors on or off which is parallel to the binary code (1s and 0s) that make up any computer operation at the most simplified state. Hundreds of millions of clock cycles are performed every second in the most average of microprocessors today, whether it being the CPU or the chip on your 3D graphics accelerator.
Clock Frequency - The clock frequency is how fast a chip performs internal operations. This is controlled by an oscillator that synchronizes operations inside the chip. Clock frequency is expressed in MHz or millions of cycles per second (or more recently, GHz or billions of cycles per second). For example, a 200MHz (200 megahertz) processor performs 200 million clock cycles per second.
Collision Detection - The ability of an object in 3D to react with other 3D objects in a realistic form is known as collision detection. When you see an object such as a box in a 3D game on the floor, what allows the box to 'know' not to fall through the floor is collision detection. As collision detection becomes more advanced and easier to process, games will become more realistic in that objects will become smaller just as their lifelike counterparts are and still react with other objects realistically.
Color Convergence - The colors red, green, and blue are mixed (often shortened to RGB), or converged, in a color monitor to make all other colors. This process is known as color convergence and is one of the many reasons a computer monitor has such a sharp display-- because of advanced, precise color convergence.
Colored Lighting - Colored lighting is the use of not only pure white light to cast shadows and to light up objects, yet other colors of light, hence the name-- colored lighting. This effect is one that many gamers today take for granted.
Component - A video signal standard on high-end televisions, DVD players, and game consoles, that separates the color into individual signals (red, blue, and green). The result is very high quality output from such devices to a television. Read more here.
Composite - This is a video signal often used on consoles, VCRs, and DVDs with low-end televisions. It uses a single analog RCA connector for video. The result is rather poor color compared to the S-wideo and Component standards. Read more here.
Compression - This term is becoming more and more important in today's computer industry. Anyone who listens to MP3s should be very appreciative, but what does it mean for 3D video? More than you think, when we talk about compression it is the ability to shrink file size without losing too much graphical detail, meaning your 3D accelerator spits out textures faster... For more info, check out the definition to Automatic Texture Compression technology. Also, see DivX codec definition.
CPU - Stands for Central Processing Unit. Although some sound cards and video cards independently process information for specific operations, almost all instructions of a computer must pass through the CPU to be 'processed'. If you compare a computer to the human body, this would be the brain. Some CPU types include the Intel Peotium IV, and AMD Athlon XP.
Culling - Although many types of culling exist, the general practice is that objects not on the screen are not being rendered. The most common are "backface" and "clustered" culling. Backface culling occurs when an object is behind you and does not need to be rendered. For example, in Quake 3, if you are looking at a wall, the objects behind your character (and point of view) are off-screen and so they are not rendered. Another method is sometimes called "portal culling". With portal culling, objects that are in the current point of view, but blocked by another object, are not rendered. For example, in Quake 3, when a character runs behind a box and is completely hidden from sight, the character model is no longer being rendered by the graphics card. Also see hidden surface removal.