Here are Michael's (Got2MuchTime) comments on the Boot article - confirming what my friends thought - Chip
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Well, in a nutshell, IMO, not much was said. Let's look at it bit by bit (as it were :-)...
"3Dfx has completed the first sampling of silicon for its next 2D/3D single-board solution, called Banshee, the company confirmed today."
This is good news, but we pretty much knew this already. Still, it's awfully nice to have confirmation at the public level that it's ready and sampling.
"Company officials say they expect Banshee to offer the fastest 2D performance in the world, while offering 3D performance consumers expect from 3Dfx."
Hmmm. what does this mean? Fastest 2D - well, assuming that they think that the G200 will be out before them, or are at least allowing for that possibility, then the 2D should truly be pretty terrific. This meets my expectations, fwiw - I expect them to do better than a Millennium II and possibly better than the G200 as well. "3D performance consumers expect from 3Dfx" is another matter, though. How charmingly vague :-). The best face I can put on this one (in terms of expecting high performance from the Banshee) is that they can't really say "fastest" if they are going to provide a 100-125MHz single-texturing device since it will be fastest in some ways and not in others (at least vs. the V2 and the G200). It really doesn't mean much of anything substantive, when you come right down to it.
"Banshee provides direct hardware polygon support that allows for the immediate drawing of polygons based on vertices data rather than relying on a middle step of software rasterization or drawing each line in the polygon. Banshee would thus be able to draw a polygon in 'tens of cycles' rather than several thousand cycles."
Unless I misunderstand this, this means that it has hardware triangle setup (like the V2 and all upcoming chips) and that it does hardware rasterization (which _all_ PC 3D hardware does). This is a big "so what" for me as I read it.
Rasterization is the process of breaking a polygon into portions of scanlines (a scanline, in turn, is all of the pixels on the nth horizontal line of the screen image) and then deciding what color each pixel in that portion should be. The coloring process is known as rendering, and the scanline portions are called spans. Basically, in a software renderer, each span is painted by code - typically pixel by
pixel - involving many calculations, and thus cycles, per pixel. This is _slow_ and is the main reason that 3D hardware has become so useful: it does all or most of the rendering in silicon, vastly
accelerating the process. Unfortunately, this is hardly unique to the Banshee - pretty much every 3D accelerator out or announced does hardware assisted rendering. Fwiw, 3Dfx hardware does it fastest to date in the sense that it maintains 1 pixel per cycle with more effects turned on than anything else out there.
As for triangle setup, what I mean is that before you can render a triangle's spans, you need to calculate information about the triangle's vertices that will allow you to, in turn, calculate what the values for various things (e.g. lighting info) are at the start and end of each span. These vertex-related values (such as lighting gradients) are relatively expensive to compute: 1st generation hardware (including the V1) accelerated rendering but left the CPU to its own devices regarding things like gradient calculations. The Voodoo 2 (and some others, including all major upcoming chips I am aware of) do this setup work for the CPU, further speeding things up. Banshee is in good company in this, but it's nothing unusual in the coming market context.
Regarding "able to draw a polygon in 'tens of cycles' rather than several thousand cycles," this is also likely non-information. It completely depends on what a polygon is: 25 pixels? 2000 pixels? If
we are talking about typically used numbers in the industry, then we are looking at triangles with 10-50 pixels, which would mean 1 pixel/cycle, like we always expected. Unless they are going to do many pixels/cycle (HIGHLY unlikely with the Banshee 1.0), then their claim means 1/cycle, which is standard on pretty much all of the upcoming and many of the currently available accelerators (the TNT lays claim to up to 2 pixels per cycle, BTW). Again, it's nice to have more
corroboration of expectations, but nothing new (or even particularly exciting).
Importantly, I see _nothing_ here to suggest true "geometry" or "lighting" acceleration, which involve calculating 3D rotations & translations, angles of incidence and other things requiring high-speed floating-point matrix manipulations, etc. They may do it, but I doubt it will be in version 1.0, and there isn't anything here to intimate such capabilities.
"Banshee will also support 256 raster operations (ROPS). Banshee will perform 99 percent of the ROPS/Blit combination in hardware rather than relying on software for these frequently used calls."
In my understanding, this is regarding _2D_ functionality. ROPS are things like (source AND destination) or (source XOR destination), which are ways of combining pixels with other pixels already in the framebuffer (or in other pixel sets). For example, do you add all the pixels going to a particular location together? Do you subtract one from another and replace the current color with the result? There are tons of these kinds of operations... say 256 :-). BLIT comes, if I recall correctly, from BLT, which means Block Transfer or Bit-block Transfer (not Bacon Lettuce and Tomato). In particular, it is the process of moving/copying a (usually rectangular) region of pixels
from one location to another - this is an incredibly common operation in a windowed operating system: moving a window, most text drawing, scrolling, etc. are all examples of operations requiring "blitting."
Together, accelerated blitting and ROPS means that the low-level 2D graphics operations required by Windows (or the Mac OS, etc.) will be done pretty much entirely in hardware. Just like all the other fast 2D boards. To be fair, many of the other 2D solutions may ignore some ROPS (accelerating a subset of those most often used, for example), making the Banshee special in this regard - I really don't know one way or the other. Either way, as I see it, this bit of the
announcement means that the 2D acceleration will be good (and isn't even much info in that way).
"Cards will be compatible with both Voodoo flavors and be optimized for Microsoft's upcoming DirectX 6.0, as well as Glide and OpenGL."
God, I should hope so! :-)
"We know more, but if we spilled the beans today, we'd be dead tomorrow."
They'll certainly live through this report, as far as I can see, since it really doesn't say anything I can identify.
BTW, I am still bullish on the company, the Banshee, Q2 EPS, etc.; I just don't find this announcement to be either exciting or even really informative in any novel or particularly substantive way.
- Michael |
