Glossary - Revision history

EricChadwick: Moving content out of the overly-large Glossary page and back into individual pages

2015-02-14T23:55:38Z

Moving content out of the overly-large Glossary page and back into individual pages

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EricChadwick: Moving content out of the overly-large Glossary page and back into individual pages

2015-02-14T23:37:58Z

Moving content out of the overly-large Glossary page and back into individual pages

EricChadwick: /* Bit Depth */ BIT DEPTH TUTORIAL

2015-02-03T17:27:33Z

‎Bit Depth: BIT DEPTH TUTORIAL

EricChadwick: Moving content out of the overly-large Glossary page and back into individual pages

2015-02-01T15:39:37Z

Moving content out of the overly-large Glossary page and back into individual pages

EricChadwick: /* Opacity */ transparency

2014-12-12T02:42:37Z

‎Opacity: transparency

Cman2k: /* Additive Color Model */

2014-11-26T09:38:50Z

‎Additive Color Model

Cman2k: /* Rotational Axis */

2014-11-26T08:58:29Z

‎Rotational Axis

Caustic at 16:33, 11 October 2014

2014-10-11T16:33:35Z

Caustic at 16:31, 11 October 2014

2014-10-11T16:31:44Z

Caustic at 16:25, 11 October 2014

2014-10-11T16:25:03Z

← Older revision		Revision as of 23:37, 14 February 2015
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−	~~__NOTOC__~~
−	~~== 2.5D ==~~
−
−	"Two and a half-D" is an optimization trick for [[RT3D]] that fakes the [[Viewer\|viewer]] into thinking they are seeing true 3D graphics. A whole scene (or an object in a scene) is made of 2-dimensional graphics that are scaled and drawn in perspective to look like [[Polygon\|polygonal]] graphics, but there are no polygons involved. This is done by projecting displacement information onto a single [[Face\|plane]]. Accordingly, this technique is limited to 2 point perspective, not allowing any [[Pitch\|Y-axis rotation]]. The groundbreaking game Doom is built entirely on this concept. [[Billboard\|Billboards]] are 2.5D, but [[Voxel\|voxels]] can be either 2.5D or 3D.
−
−	~~Other effects classified as 2.5D can include [[Parallax_Map\|parallax]] scrolling effects or orthographic 3/4 perspective (popularized by many real-time strategy and role-playing games).~~
−
−	~~= '''A''' =~~
−
−	~~== Additive Blending ==~~
−
−	A [[TextureBlending\|texture blending]] method that uses the [[AdditiveColorModel\|Additive Color Model]]. The [[Pixel\|pixels]] of a [[BaseMap\|base map]] and a [[Light map\|light map]] are blended together to make a brighter texture.
−
−	See also [[AdditiveColorModel\|additive color model]], [[AdditiveTransparency\|additive transparency]], [[AverageBlending\|average blending]], [[BlendInvert\|invert blending]], [[BlendSubtract\|subtractive blending]].
−
−	~~see [[additive color model]]~~
−
−	~~== Additive Transparency ==~~
−
−	A way to calculate the color behind a transparent object, using the [[AdditiveColorModel\|Additive Color Model]]. In general, wherever the object is more [[Opacity\|opaque]], the brighter the background. If you use an alpha channel to change the transparency, the white areas get brighter, and the black areas have no effect on the background. This works well for flames, explosions, lens flares, etc., because it makes them look cleaner and hotter. If you use [[Material\|material]] opacity, it makes the whole background behind the object the same brightness level: the more opaque the object, the brighter the background, and the lower the opacity, the less bright the background. This works well for things like water or prisms or holograms. See also [[AverageTransparency\|average transparency]], [[SubtractiveTransparency\|subtractive transparency]].
−
	== AI ==		== AI ==

@@ Line 133: / Line 133: @@
 The number of colors at any bit depth = 2bitdepth. For instance, 8-bit = 28 = 2x2x2x2x2x2x2x2 = 256 colors.
 If game uses alpha or [[HeightMap|heightmaps]], then they are additional channels that can be added to the bitdepth number. 16-bit is 65536 colors without any additional channels, but if you want to add an alpha channel, then 16 would be divided into [[RGB]] and alpha, which can be done a number of ways. For example, if you use 4 bits each for Red, Green, and Blue, then that leaves 4 bits for the alpha, so you have 16 colors for alpha. Or else 5 bits for each RGB means you have 1-bit for alpha, which is only 2 colors, but gives you more RGB colors to work with. It's a trade-off.
 == Bitmap ==

← Older revision		Revision as of 15:39, 1 February 2015
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	When edges look jagged instead of smooth, and moiré patterns develop in fine parallel lines. The problem is most prevalent in diagonal lines. Aliasing happens when the engine tries to display an image on a portion of the screen where the resolution is too low to display its details correctly. This is solved with [[Anti-Aliasing\|anti-aliasing]], [[Mip Mapping\|mip mapping]], or [[Texture Filtering\|texture filtering]].		When edges look jagged instead of smooth, and moiré patterns develop in fine parallel lines. The problem is most prevalent in diagonal lines. Aliasing happens when the engine tries to display an image on a portion of the screen where the resolution is too low to display its details correctly. This is solved with [[Anti-Aliasing\|anti-aliasing]], [[Mip Mapping\|mip mapping]], or [[Texture Filtering\|texture filtering]].
−
−	~~== Alpha Channel ==~~
−
−	~~An optional channel in the texture file that usually defines the [[Transparency map\|transparency]] of the texture’s [[Pixel\|pixels]].~~
−
−	~~It can also be used for other things like a [[Height map\|height map]] or grey-scale [[Category:Specular map\|specular map]].~~
−
−	The alpha is usually anywhere from 1bit up to 8bits, depending on the amount of detail you need. Generally, the lower the [[BitDepth\|bit depth]] you use, the more [[Memory\|memory]] you save, but the less image quality you get. See [[Transparency map]] for more information, and some visual examples can be found on the Glossary page [[Transparency#Alpha_Bit_Depths]].
−
−	Different image channels can be extracted by a [[Category:Shaders\|shader]] to use them for particular effects, like alpha for physics info, red channel for glow and green channel for specular and blue channel for sound types, etc. In this way, a bitmap can store more information than just RGB color.

	== Ancestor ==		== Ancestor ==

@@ Line 556: / Line 556: @@
 {{:[[OutOfDate]]}}
-Opacity (opaque) is the opposite of transparency (transparent). Opacity can mean that something is partially transparent-- because you can change an object's opacity using a setting in its [[Material|material]]. But the word opaque usually means totally non-transparent.
+Opacity (opaque) is the opposite of [[Transparency_map|transparency]]. Opacity can mean that something is partially transparent-- because you can change an object's opacity using a setting in its [[Material|material]]. But the word opaque usually means totally non-transparent.
 == Overdraw ==

@@ Line 14: / Line 14: @@
 See also [[AdditiveColorModel|additive color model]], [[AdditiveTransparency|additive transparency]], [[AverageBlending|average blending]], [[BlendInvert|invert blending]], [[BlendSubtract|subtractive blending]].
-== Additive Color Model ==
+see [[additive color model]]
-−
-{{:[[OutOfDate]]}}
-−
-In the additive color model, red, green, and blue ([[RGB]]) are the primary colors, and mixing them together creates white. This is the way light blends together-- shine a red, a green, and a blue spotlight in the same place, and it will make white light. You add to get white. To get a lighter color use more of each color, or to get a darker color use less of each color. Additive is the color model used to display graphics on your computer screen, where all the colors are just combinations of the colors red, green and blue. Also called RGB space. See also [[SubtractiveColorModel|subtractive color model]], [[TextureBlending|texture blending]].
 == Additive Transparency ==

@@ Line 678: / Line 678: @@
 == Rotational Axis ==
-See [[Rotational Axis|RotationalAxis]]
+See [[Rotational Axis|Rotational Axis]]
 == RT3D ==

@@ Line 199: / Line 199: @@
 == Channel Packing ==
-See [[Channel Packing|ChannelPacking]]
+See [[ChannelPacking|Channel Packing]]
 == Child ==
@@ Line 233: / Line 233: @@
 == Color Models ==
-See [[Color Models|ColorModels]]
+See [[ColorModels|Color Models]]
 == Compile ==

@@ Line 199: / Line 199: @@
 == Channel Packing ==
-See [[ChannelPacking]]
+See [[Channel Packing|ChannelPacking]]
 == Child ==
@@ Line 233: / Line 233: @@
 == Color Models ==
-See [[ColorModels]]
+See [[Color Models|ColorModels]]
 == Compile ==
@@ Line 289: / Line 289: @@
 == Displacement map ==
-See [[Displacement_map]]
+See [[Displacement Map|Displacement_map]]
 == Draw Order ==
@@ Line 678: / Line 678: @@
 == Rotational Axis ==
-See [[RotationalAxis]]
+See [[Rotational Axis|RotationalAxis]]
 == RT3D ==
@@ Line 812: / Line 812: @@
 == Value correction ==
-See [[Value_correction]]
+See [[Value Correction]]
 == Vertex ==

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 The texture used to [[Blend|blend]] with the [[BaseMap|base map]] to create a new, darker texture. See also [[Light map|light map]], [[BlendSubtract|subtractive blending]].
 == Decal ==
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 Astronomers use only two axes (the other axis is [[Azimuth|azimuth]]), because they do not use [[Roll|roll]]. This is similar to the way most [[FPS|FPS]] games work. It is preferred in some RT3D engines because it keeps the [[Viewer|viewer]] level no matter where it points. But this system has a drawback because it suffers from [[GimbalLock|gimbal lock]] whenever the viewer points either straight up or straight down.
 == Draw Order ==
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 = '''G''' =
 == Geometry ==
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 See also [[B-Spline|b-spline]], [[BezierSpline|bezier spline]].
 == Storyboard ==
@@ Line 793: / Line 809: @@
 = '''V''' =
 == Vertex ==