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From: BLuRry on 24 May 2006 16:16 >Let's talk about Java 2 !!! :-) **vomits** Ok, I'll give the critics that much. Java 1.2 was far from fantastic in terms of performance. ;-) But if anyone has still neglected to update to at least 1.3, I have no pity... (hey, when is this thread gonna die?!)
From: Cameron Kaiser on 24 May 2006 18:42 "Michael J. Mahon" <mjmahon(a)aol.com> writes: >>>>The C64 mainly needed it for its text mode. Unlike the Apple, the >>>>character shapes reside within the Video chip's AND the CPUs normal >>>>memory map, are read over the normal address bus, and can be redefined >>>>by pointing a register to RAM instead of ROM. >>>It was a conscious choice to make the Apple character set fixed. >>>(And it's nice to have a character set fully defined at power-up.) >>This is a marginal diversion, but I'm not sure what you mean by "fully >>defined" since the C64's is, of course, also fully defined in the sense >>that it's there. :) >I meant that there was no SRAM to initialize to provide a character >set--but perhaps I misunderstood the explanation of character generation >in the C=64. Ah, okay. In the C64's case, there isn't a need to copy to RAM either; the VIC-II video chip can simply use Character ROM as it is positioned in the default memory map. The sole difference is that the character set doesn't *have* to come from the Character ROM; it can come from most other places in RAM, too. But it is fully defined and ready to go on start-up without loading it into RAM, yes. -- Cameron Kaiser * ckaiser(a)floodgap.com * posting with a Commodore 128 personal page: http://www.armory.com/%7Espectre/ ** Computer Workshops: games, productivity software and more for C64/128! ** ** http://www.armory.com/%7Espectre/cwi/ **
From: Eric Smith on 24 May 2006 19:11 "Michael J. Mahon" <mjmahon(a)aol.com> writes: > Of course, the character generator ROM could have been an SRAM, and > could have been made visible (byte sequentially, say) on an Apple. > > It was a conscious choice to make the Apple character set fixed. > (And it's nice to have a character set fully defined at power-up.) The Apple III used an SRAM for the character generator, but it wasn't directly memory mapped. The boot ROM contained a very crude partial character set which was decompressed and loaded into the character generator RAM at power-up. Once the operating system was booted, the SOS driver for .CONSOLE was responsible for the character generator. It loads a default character set, and provides a way for an application to change it. The Apple II emulation disk loads the Apple II character set. The way the hardware works is that you load the character set image into main RAM, then set a bit on one of the VIA ports. This makes the video hardware copy the character set from main RAM into the character generator RAM. Pretty clever, and it avoids needing faster main RAM that would be needed if the character generator was mapped in main RAM.
From: sicklittlemonkey on 24 May 2006 22:49 > Lol, yeah Java on mobile is an especially cool example of "Java power" > where Giana Sisters runs jerky as hell on a ~300 MHz CPU, while a lame > old 1 MHz 8 bit computer could do it smooth in 50 fps. It's not clear what you're criticisizing here. A poor re-implementation of a particular game; a poor JVM implementation on a particular platform ... > I have yet to see an example of pure rendering where a JIT comes even > close to lame C++ programming. This is why I mentioned Java Quake (Jake2) which in some cases exceeds the framerate of the original C version: http://www.bytonic.de/html/benchmarks.html Anyway, we seem to have strayed off the path ... Cheers, Nick.
From: Paul Schlyter on 25 May 2006 02:42
In article <1148507979.618765.249330(a)j73g2000cwa.googlegroups.com>, BLuRry <brendan.robert(a)gmail.com> wrote: > I mean, with all those non-standard compiler directives you know they were > going to try to poison java's portability anyway so they stay at the top. What "Java portability" ???? Java is not a portable language. Java is less portable than both FORTRAN, C or C++, which runs on several platforms. Java runs on one single platform only: the Java platform. The Java platform doesn't exist in hardware - it must be simulated in software. "But that means Java is portable: I can run my JVM on several other platforms" -- true, but if you define "portability" in such a way, then all Windows software becomes equally portable: just start your favourite Windows emulator on either your Mac or your Linux machine, and run your Windows software on it.... -- ---------------------------------------------------------------- Paul Schlyter, Grev Turegatan 40, SE-114 38 Stockholm, SWEDEN e-mail: pausch at stockholm dot bostream dot se WWW: http://stjarnhimlen.se/ |