00:07Hi, this is Tom Peterson with NVIDIA, and today I want to introduce you to our next-generation GPU architecture,
00:13Maxwell.
00:14It comes in two variations, GTX 980 and GTX 970, both of which use the power of architecture to give
00:21you the best perf per watt possible.
00:23These are the world's most advanced GPUs. The GTX 980 delivers 2x performance over the GTX 680, and in fact,
00:31it's the fastest GPU we've ever created.
00:34The 970 is no slouch in its own right, with best-in-class performance stacked with cutting-edge features.
00:41Of course, since these GPUs are based on the new Maxwell architecture, they deliver performance in an incredible 165 watts,
00:49which means your PC will be whisper quiet as it crushes through the latest games.
00:53And we're delivering better gameplay experiences using cool new technologies.
01:00Multi-Frame Anti-Aliasing, or MFAA, is one example where we can deliver high-quality AA at much higher performance.
01:08It's a simple idea that says by looking at multiple frames over time, we can actually combine them and generate
01:15an image with the same quality as MSAA,
01:18but we can do that at a fraction of the performance cost of traditional multi-sampling.
01:23Let's start to understand MFAA better by understanding how AA works.
01:28This image shows a grid of 25 pixels that represents a very small area of your screen.
01:33If a game draws a straight line on this grid, the GPU must determine the correct color to use for
01:39each pixel.
01:40The way the GPU does that is by sampling, and sampling means that we pick some location, which in this
01:45case is the very center of the grid,
01:47to use as the test location to determine if a geometric shape intersects a pixel and should thus color it.
01:55You can see that we get a very jagged edge when we use one sample since each pixel needs to
02:00make a binary decision about coverage.
02:02Traditional AA improves this a lot by taking more than one sample per pixel.
02:07In this image, we're showing two sample points per pixel.
02:11Now for each pixel, the GPU calculates two coverage points.
02:14If a particular geometry covers only one of the two sample points, then the final pixel color is of course
02:20the average of the two colors.
02:22This technique dramatically improves image quality by reducing jaggies, but the cost can be high as now the GPU needs
02:29to do more calculations on each frame.
02:33MFAA dramatically improves this by recognizing that the averaging that MSAA does per pixel can actually be done over time.
02:41In the first frame, let's assume that the following grid of sample positions is used.
02:46You can see the image here is similar to what no AA looks like.
02:49Now in the next frame, we change the sample positions.
02:52You can see how the generated image is slightly different from the prior frame, with just a few pixels changing
02:58from light to dark and vice versa.
02:59We can then run a sophisticated filter on the GPU to combine the series of frames and deliver an image
03:05that's nearly identical to 2x MSAA.
03:08The great part about this tech though is that the delivered performance is nearly identical to no AA.
03:18Dynamic Super Resolution, or DSR, is a great new Maxwell technology that allows you to get a 4K experience on
03:24a 19x10 monitor.
03:26The way it works is pretty simple.
03:29GPUs use a frame buffer to store a rendered image before they're scanned onto a monitor.
03:34Most of the time, that buffer is organized at a resolution that matches the resolution of your monitor.
03:39But many gamers have found that sometimes it's desirable to lower the resolution of the frame buffer to get higher
03:45frame rates out of the GPU.
03:46In this case, the GPU scales up the rendered image as it's scanned onto the monitor.
03:51DSR, however, goes the other way.
03:54With Super Resolution technology, we allow the game to specify a resolution that's actually larger than your monitor.
04:00This means the GPU will generate a very high quality image in the local frame buffer, and then use a
04:05sophisticated filter to downscale it and put it onto your monitor.
04:09This reduces artifacts caused by rendering at low resolutions.
04:13This image, as an example, is a fragment of an image generated at 19x10.
04:19That same scene is shown again here, but now it's rendered at 4K using DSR, and then it's downscaled to
04:2519x10.
04:26The image we're showing is exactly as it would appear on your monitor, and comparing the two, you can see
04:31the improved texture and edge quality.
04:34This technology works really well with objects in motion as well.
04:38Let's take a look at this 19x10 image here, running without DSR.
04:43Notice the scintillation in the grass as textures kind of pop in and out.
04:47In the second sample, you can see the image is much clearer, and the objects look much more solid.
04:54Let me tell you a little bit about VXGI, or Voxel Global Illumination.
04:59It's a technology that allows us to simulate light inside of your game in real time.
05:04That means that shadows look better, colors bounce around, and the scene is much more realistic.
05:11You're looking at a ray-traced image of the Cornell box, which is a classic set of geometry from the
05:16early days back in 1984,
05:18when everybody was trying to figure out how to do real-time rendering.
05:21The problem with this box is that it's actually very difficult to calculate how light bounces around it in real
05:27time.
05:27So in graphics, we use simplification techniques.
05:30The easiest way to calculate light is what's called direct.
05:33That means we imagine there's a point light source that illuminates directly down onto the geometry,
05:38but only lights the surfaces that it hits directly.
05:41That's why we call it direct light.
05:42In this case, you can see the top of the balls are very bright white.
05:46The right wall is green and the left wall is red.
05:48And that direct light kind of, it looks good, but it's missing because clearly you understand that there's going to
05:54be reflections.
05:55Well, reflections and calculating reflections in real time has been a really difficult problem for graphics.
06:00And really, until now, it's been practically impossible.
06:04This image is showing a voxel view of that geometry.
06:08Now, voxels are volume pixels, and it's a way to represent geometry sort of coarser so that we can model
06:14real-time light reflectivity.
06:17In this view, you're looking at what we call an opacity model.
06:20And the opacity model is used to calculate how light is blocked by objects.
06:25And you can see that it's made up of these tiny little boxes.
06:28That simplification versus the real geometry helps us run this in real time.
06:33Now, the next view you're looking at is called an emissive view.
06:37In this view, we're taking direct light and we're lighting the voxels.
06:41And then we're going to, in the next stage, use that lit voxel to calculate the first bounce of light.
06:47In this case, you can see the right-hand wall is very green and the left-hand wall is very
06:51red.
06:51In the next stage, those surfaces are going to emit light onto the rest of the surroundings.
06:57That's effectively how we calculate reflection.
07:00Now, as I move the light around, you can see that the voxel geometry is actually changing in response to
07:06the way direct light is illuminating the scene.
07:09This is just another way to say, okay, we're going to calculate a bounce.
07:12So if you look, as that light pans from the green wall to the red wall, the white voxels appear
07:17and disappear.
07:18In this next scene, the voxels are now emitting light or reflecting the original direct light.
07:24You can see the ball on the left-hand side has this sort of reddish glow to it.
07:28That's there because, remember, the left wall is emitting red light.
07:32And on the right-hand side, you can see there's kind of a green pale to the right-hand ball.
07:37And that, again, is coming from the right-hand wall, which is emitting green light.
07:42What's interesting, though, is you can also see both walls are now kind of the opposite color that they were
07:46originally.
07:46Because, of course, each wall is gently lighting the other side.
07:50This gives you a real sense of how reflected light would work in the real world.
07:54And now we're able to do that in real time.
07:56And now let's take all those different forms of light and combine them together to get a final image.
08:01In this scene, you're looking at the direct light coming from the top and it's hitting the walls.
08:06And we're adding in that light that we calculated using VXGI.
08:10That light gives us the specular highlights.
08:13It gives us very beautiful ambient occlusion.
08:15The balls look like they're on the ground.
08:17What's really extra cool is that you can see the reflection of one ball in the other ball.
08:21If you look closely at the ball in the back, you can see this interesting silver shape,
08:25which is actually the ball in the front.
08:28VXGI is a revolutionary new dynamic lighting technology being delivered with Maxwell GPUs.
08:33It's going to change the way games look forever.
08:36And we're all going to be the better for it.
08:41The advancements extend beyond the new technologies to new ways to play.
08:45Maxwell offers the best solution for 4K gaming.
08:48With the horsepower to hit the frame rates you gotta have.
08:51And 4K surround using SLI.
08:53And even 4K shadow play.
08:55You can now take your PC gaming on the road with GameStream and our Shield family.
09:00And of course, GTX 980 is ready for the next generation of games,
09:04with full support for DX12 and virtual reality.
09:07With new technologies like MFAA, DSR and VXGI,
09:11they are simply the best choice for serious gamers.
09:14We'll be right back.
09:16Let's get started.
09:18We'll be right back.
09:19We'll be right back.
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