Hot answers tagged

24

There's something of a conflation here of antialiasing and filtering, I think. Antialiasing is literally preventing things from adopting aliases — e.g. if a diagonal line looks like a staircase rather than a diagonal line, it has adopted an alias. So you can imagine the same thing happening to textures as they rotate or take awkward angles. But it's always ...


19

The NES did not use an extra bit for sprite positions. A sprite's X-position was the position of its left edge, which means that sprites cannot be placed partially off the left side of the screen: However, the NES did actually provide the feature you're suggesting, in a way: bits 1 and 2 of the PPUMASK register can be used to keep the leftmost 8 pixels of ...


11

The first generation of consoles use proprietary APIs; I can speak directly as to the PS1. In the PS1's case there's a vector coprocessor for performing 3d transformations and one is subsequently responsible for compiling and supplying list of triangles in direct screen coordinates for drawing. Usually calculated via the vector coprocessor, but it's up to ...


11

On paper, based on the fill rate only, all the high-end graphics adapters available on PC in 1999 were at least as powerful as the Dreamcast’s PowerVR2: the CLX2 in the Dreamcast ran at 100MHz, with one operation/pixel/texture per clock, and memory bandwidth of 0.8GB/s; the PMX1 (PC-compatible PowerVR2) ran at 125MHz, again with one operation per clock, and ...


11

The price difference was indeed entirely in the packaging. The important thing to remember about mask ROMs is that, though the setup costs and lead times were high, they had the lowest marginal cost of any form of memory. The reasons behind this are fairly clear if you look through this ROM, EPROM, & EEPROM Technology document from Integrated Circuit ...


9

[not a complete answer, but some remarks too big for a comment] [also it focuses on games, as they are the most complex, real time application. Antialiasing for desktop UI and editors are a fairly insensitive issue and a subset thereof] Need for Colours A point, often forgotten from today's view is that antialiasing does need a video system systems with ...


7

Those companies did implement their own graphics APIs that were very light weight and didn't have too much complex functionality. This was done because their libraries could be tailored to the strengths or weaknesses of their system. They also had very unique architectures that took different approaches to producing 3D graphics. Later on, consoles and PC ...


6

This was in no way part of a hardware assisted 3D pipeline, but there were attempts made in PC-class hardware to achieve anti-aliasing even as early as 1990. Edsun Labs made a drop in replacement RAMDAC for VGA boards that used some of the 256 possible color values as opcodes that would enable color blending between pixels on a line. This let a nominally ...


6

They have different memory and IO maps. The ColecoVision has a boot ROM at address 0000h and an inserted cartridge appears at 8000h. The Sega has no boot ROM so just maps the inserted cartridge at 0000h. RAM is at C000h on the Sega, 6000h on the Coleco. The Coleco's TMS is addressable between ports 40h and 7fh (including mirroring) but the Sega's is at BE ...


4

256 is the maximum number of pixels per row, but most games used fewer. Using fewer pixels allowed for partially off-screen sprites with only 8 bits of position information. Most hardware of that era allowed some flexibility with screen resolutions. While the timing for the display (PAL or NTSC) was fairly well nailed down, the programmer could choose to ...


3

I heard "on the grapevine" that Sega, with their benchmarks, felt CLX2 outperformed the PC parts of that era. Although CLX2 'only' had peak texture & shading fill rate of 100Mp/s, it performed rasterisation and hidden surface removal at a peak rate 32x higher, i.e. 3.2Gp/s. Thus for 3D worlds where there is nearly always a reasonable amount of ...


3

the stuff you are describing has nothing to do with x resolution selection. In the 8 bit era CPUs didn't have mul , div instructions so computing *,/ was really expensive. That is why the x resolution is usually power of 2. That allows to compute pixel address from x,y coordinates using just basic ALU operations. For example on 256 pixels per line and 1 ...


3

But the first systems didn't run an OS like that? Well, they did, some kind of proprietary OS. So how graphics were programmed to these machines? Using functions of said OS, or bare bone. Did the companies developed and implemented their own graphics APIs (like OpenGL)? Exactly. Just usually a lot less advanced than that. It might be useful to keep ...


3

Furthermore, (correct me if I'm wrong) the Commodore Amiga can also read a joystick button wired this way being pushed, as although it treats pin 9 as an analog input, the Amiga's analog pins are active low. All the "early" Atari-derived systems read pins 5 and 9 as analog. There may be later designs, like MSX, that work differently, but the Atari, C64 and ...


1

In addition to the above explanations re: sprites actually only having 8 bits of position resolution, the first column blanking option etc, the NES - and others following its same general design - actually had another, simpler, more physical tactic to address the problem: Overscan. The pixel generator clock, derived from the NTSC colourburst crystal by some ...


1

According the the German Wiki there was no game successor but a rather rare fan-manga called "Landstalker 2 - Heart of Diamond". Maybe thats where your memory is based on? There where several games based on the same engine/principles on other systems, but no direct follow up. Another candidate may be a revival in 2006, called "Landstalker 3D", for the ...


Only top voted, non community-wiki answers of a minimum length are eligible