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- Path: nntp.teleport.com!sschaem
- From: sschaem@teleport.com (Stephan Schaem)
- Newsgroups: comp.sys.amiga.programmer
- Subject: Re: Amiga doesn`t need Planar!
- Date: 28 Jan 1996 00:42:33 GMT
- Organization: Teleport - Portland's Public Access (503) 220-1016
- Distribution: world
- Message-ID: <4eegpp$pte@maureen.teleport.com>
- References: <john.hendrikx.48yl@grafix.xs4all.nl>
- NNTP-Posting-Host: julie.teleport.com
- X-Newsreader: TIN [version 1.2 PL2]
-
- John Hendrikx (john.hendrikx@grafix.xs4all.nl) wrote:
- : I think that Chunky can still do that better. Most Chunky cards have got a
- : 16-color mode where 1 byte represents 2 16-color pixels. Although lots of
- : advantages of Chunky are lost this way it would still be faster to plot a
- : pixel, draw a vertical line and stuff like that vs 4 bitplane Planar.
-
- For gfx planar is not too cool... but like planar can save memory,
- it can also save bandwidth. A basic example is CED, only write/scroll
- 1 bitplane. Now if amiga only had chunky and it was opnened on a 8bit
- screen and had no blitter, ced would be 8 time slower for its display
- operation.
- I dont know if you do this, but if I clear a rectangle and do operation
- on the rectangle that wont overlap themself I mask out the plane that
- will be set or cleared to its already set value.
- ex: You write black onto gray... only 1 bitplane out of the 8 will
- be accessed: to blit a rendered string buffer of 128x8 would need
- 32 read/write to past the string, chunky 256 read/write (Plus 8x too
- the bandwidth to create the string buffer in chunyk format: pc card
- support 2 color text blit but maybe not all:)
- Now you want to higlight the text in 'blue' , you just need to write
- a rectangle in 1 bitplane and you have a blue highlight (of white or
- black text on gray). in chunky you would need to read & write (I assume
- there you OR or XOR)
-
- Just a counter example... That doens't mean I would choose this
- VS chunky... But I would be interested in having an xbit plannar
- overvlay.
-
- A planar index buffer + a true color buffer... I would love that.
- probably one dedicated to GUI still work the other true color work.
- (the index color of the planar buffer could be 32bit and offer 8bit
- mixing with the back true color buffer, or the other way around
- 32bit over a 256 color background)
-
- BTW I thiking of all this because of realtime multimedia...
- A bit off the subject, but a video card like this is my dream :)
-
- Stephan
-