Usage
When the Amiga was launched in 1985, HAM mode offered a significant advantage over competing systems. HAM allows display of all 4096 colors simultaneously, though with the aforementioned limitations. This pseudo-photorealistic display was unprecedented for a home computer of the time and allowed display of digitized photographs and rendered 3D images. In comparison the then IBM-PC standard EGA allowed 16 on-screen colors from a palette of 64. EGA's successor VGA released in 1987 with its flagship games mode, Mode 13h, allowed 256 on-screen colors from 262,144. HAM mode was frequently used to demonstrate the Amiga's ability in store displays and trade presentations, since competing hardware could not match the color depth. Due to the limitations described above HAM was mainly used for display of static images and developers largely avoided its use with games or applications requiring animation.
With the introduction of the Advanced Graphics Architecture a conventional planar image could have a palette of 256 colors with significantly higher color fidelity. Arguably, the original HAM mode with its limited color resolution became far less attractive to users of an AGA machine, though it was still included for backward compatibility. The new HAM8 mode was arguably far less useful to the AGA chipset than the HAM mode was to the original chipset, since a planar 256-color palette greatly increased the options to the artist without suffering from the drawbacks of HAM mode. A well-programmed sliced planar mode could prove to be more useful than HAM8. The original purpose of HAM, which was to allow more color resolution despite limited video buffer size and limited memory bandwidth, was no longer as relevant.
As modern computers are capable of high resolution truecolor displays there is no longer any need for display techniques like HAM. Planar graphics are now also obsolete for general purpose computing, since modern graphics hardware has enough memory bandwidth to used packed pixels.
Read more about this topic: Hold-And-Modify
Famous quotes containing the word usage:
“Pythagoras, Locke, Socrates—but pages
Might be filled up, as vainly as before,
With the sad usage of all sorts of sages,
Who in his life-time, each was deemed a bore!
The loftiest minds outrun their tardy ages.”
—George Gordon Noel Byron (1788–1824)
“I am using it [the word ‘perceive’] here in such a way that to say of an object that it is perceived does not entail saying that it exists in any sense at all. And this is a perfectly correct and familiar usage of the word.”
—A.J. (Alfred Jules)
“Girls who put out are tramps. Girls who don’t are ladies. This is, however, a rather archaic usage of the word. Should one of you boys happen upon a girl who doesn’t put out, do not jump to the conclusion that you have found a lady. What you have probably found is a lesbian.”
—Fran Lebowitz (b. 1951)