
Extra Half Brite (also referred to as Extra-Half-Brite, Extra-Halfbrite, or EHB),
is a
planar display mode of the
Amiga
Amiga is a family of personal computers produced by Commodore International, Commodore from 1985 until the company's bankruptcy in 1994, with production by others afterward. The original model is one of a number of mid-1980s computers with 16-b ...
computer.
This mode uses six
bit planes (six bits per pixel).
The first five bit planes
index
Index (: indexes or indices) may refer to:
Arts, entertainment, and media Fictional entities
* Index (''A Certain Magical Index''), a character in the light novel series ''A Certain Magical Index''
* The Index, an item on the Halo Array in the ...
32 colors selected from a
12-bit color space of 4096 possible colors. If the bit on the sixth bit plane is set, the display hardware halves the
brightness
Brightness is an attribute of visual perception in which a source appears to be radiating/reflecting light. In other words, brightness is the perception dictated by the luminance of a visual target. The perception is not linear to luminance, and ...
of the corresponding color component. This way 64 simultaneous colors are possible (32 arbitrary colors plus 32 half-bright components) while using only 32 color registers. The number of color registers is a hardware limitation of pre-
AGA chipsets in Amiga computers.
Some contemporary games (''Fusion'',
''
Defender of the Crown
''Defender of the Crown'' is a strategy game, strategy video game designed by Kellyn Beeck. It was Cinemaware's first game, and was originally released for the Amiga, Commodore Amiga in 1986, setting a new standard for graphic quality in home co ...
'',
''Agony'', ''
Lotus II'', or ''
Unreal'') and animations (''HalfBrite Hill''
) use EHB mode as a hardware-assisted means to display shadows or silhouettes.
EHB is often used as general-purpose 64 color mode with its own restrictions.
Some early versions of the first Amiga, the
Amiga 1000
The Amiga 1000, also known as the A1000, is the first personal computer released by Commodore International in the Amiga line. It combines the 16/32-bit Motorola 68000 CPU which was powerful by 1985 standards with one of the most advanced grap ...
, sold in the
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...
, lack the EHB video mode, which is present in all later Amiga models.
See also
*
Original Chip Set
The Original Chip Set (OCS) is a chipset used in the earliest Commodore Amiga computers and defined the Amiga's graphics and sound capabilities. It was succeeded by the slightly improved Enhanced Chip Set (ECS) and the greatly improved Advanc ...
*
Hold-And-Modify
References
External links
Animated demo using Halfbrite mode(requires
Java
Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...
)
Amiga Graphics Archive - Extra Half-Brite
{{Amiga hardware
Computer display standards
Amiga
Color depths