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Gaming Beauty Is Only Pixel Deep
Thanks to NTSC-uk for its feature discussing what the new pixel and vertex shaders mean to this generation of videogames. The piece laments: "Looking back at the past few years, games have looked incredibly similar. And this is the main reason why: they all used the same tools", before going on to explain: "The hardware previously contained logic circuits to simply perform the operations needed by Gouraud and Flat shading, but now the fully Programmable Pipeline has introduced a whole new world of graphical effects for us all, limited only by the programmers' time and creativity", referencing "the water effects used in Super Mario Sunshine, cel shading effects used in Zelda, or the rippling water effects on Dead or Alive 3."
The Gamecube doesn't have a programmable function pipleline for graphics effects - it has a very robust fixed function pipeline. The effects the author emphasizes in those three Gamecube Games were more than likely done on the CPU and not with a programmable GPU. While that doesn't diminish the look or technical achievement of those games it does throw water on the author's assertion that games all looked alike before GPUs because all fixed function pipelines give the same look to their output.
It could mean less stress is on the CPU, meaning the physics can be more realistic and funner and the AI can be smarter, giving a better gaming experience.
^_^
That's like saying "because power tools are now popular, all buildings look the same". The reason why games are looking similar is that developers are sharing some of the more common code (as they should do). It's similar to when games first became color and all of them looked like blotchy squares. Over time the graphics start to vary. Give them time.
Even though I haven't thought of that when I wrote my comment, this is a very interesting thing.
In old games, to get to a high place, you need to find the correct set of crates/ledges that just "happen to be there" if such existed, or click a specific button that will let you eradicate your enemies fast.
In new games, they just put reasonable world features in a way that you can CLIMB on them and get where you want to go, even if the game designers didn't think going there could help. Or just place some barrels somewhere and u could shoot/push them and expect them to roll down on your enemies.
It becomes so that there is more than one way to achieve your goal.
It's funner to see your char doesn't need to find a teleporter to go over a 0.5meter ledge (doom2, lvl2) but do what YOU as the player would like to do at that situation.
Ofcourse the devs need to make sure you don't go to places you shouldn't go to if the storyline dictates, but not thru stupid things like tiny wall that a human could easily pass.
^_^
Different gameplay experiences are not caused by games looking different. They come from different game designs.
Games aren't going to use the standard fixed-function pipeline any more- they're all going to use the same shader programs. There's only one "best" way to implement character model normal mapping, and that's polybump, which virtually everyone is using for upcoming games. There are only 2 ways to do shadows, shadow buffers or stenciling, and both of those are very common. The only exceptions are going to be games making really unusual style choices like Jet Set Radio Future. What's really going to differentiate games in the future is going to have to be something other than graphics and physics, as those fields tend to converge onto a single "one true implementation" as they evolve (for graphics it's photorealism, for physics it's something like Havok which is available for anyone to just drop into their games).
Good article? It's terrible:
...then they are split into triangles for simpler rendering (Due to the mathematics that states that any polygon can be formed by multiple triangles)."
"Most 3D objects are made from triangles. A triangle is given by three points in space. If they are modeled as polygons, by the time they are drawn on the screen (rasterised)..."
Rasterization is the process by which an aribtrary mathematical representation is converted into a raster image (an image composed of a grid of orthogonal display elements). Rasterization is not when something is drawn on the screen.
Complex representations of three dimentional objects are not split into triangles for simpler rendering, they are split into triangles because it allowed for faster rendering.
There is no statement in mathematics that claims any polygon can be formed by multiple triangles. Furthmore, this claim is false.
"The whole process of rendering takes each triangle in 3D world space, and projects them onto the screen as 2D triangles."
This claim is false. If you are projecting three space triangles onto a cartesian plane, they do not necessarily become triangles. Lines, points, and nothing at all are not triangles.
"The most basic method of lighting is simply giving each triangle a flat colour, and by no coincidence at all, this is called Flat Shading."
This is not lighting -- it is called shading. The process of selecting the actual colour of the polygon would be considered a rudamentary lighting model, not simply the assignment of a colour. Again, shading and lighting are independant.
"Cel shading techniques can make use of the fast rendering speed to save some processing power for the pencil outlines, so it's still a relevant shading method. I, Robot was one of the first games to take advantage of this technology."
As before, the ambiguity of the last statement is enjoyable -- "I, Robot" was one of the first games to use 3D polygonal representations. It was not one of the first games to use flat shading, nor cell shading (given that it does not use cell shading).
"The next shading technique, which was common in the later days of the PlayStation, is named Gouraud Shading:..."
Gouraud shading was first presented by Henri Gouraud in 1971 and has been common in games well before PlayStation.
"...by working out the colour at each vertex, and interpolating this colour between the vertices across the triangle whilst rendering, it will give an approximate idea of how the triangle should be shaded."
Gouraud shading takes the averaged surface normals at each vertex and performs a lighting computation (originally a Lambertian diffuse calculation) upon them. The resulting vertex colours are then interpolated along the edges of triangle, then the triangle is filled by interpolating between each set of edge pixels per a scanline.
"Unfortunately, because the colours are worked out at the corners and mixed across, shadows in the middle of the triangle will be completely missed."
The production of shadows has nothing to do with Gouraud shading, or shading at all.
"Also, when using large triangles, the effect can seem quite unnatural, and it's especially noticeable in Metroid Prime when moving around in Morph Ball mode."
The problem with Gouraud shading is that it restrict light sampling to vertices taken from the world geometry. The accuracy of the shading is then directly proportional to the vertex density of the world geometry. It also performs poorly at oblique junctions. Another issue is the Gouraud shading is not perspective correct.
"Games such as Silent Hill 2, however nice the shadow generation is, still only use this basic shading model, and it's very noticeable with the 'squares' since the light hits the vertices (corners) in turn, the light tends not to spread slowly across the triangles."
But I always bristle at the notion that "games lately look so much the same" and "there's no originality anymore, not like back in the day".
Here's the deal: the reason why so many games look the same is because for every innovative game you have 20 or so derivative titles that want to cash in on the popularity of the original. Though we like to fondly look back to the early days of video games and think that they were so original, the truth is that the same problem existed back then as well. I recently got one of those 200-in-1 NES emulators for the GBA, and let me tell you that the 20-to-1 ratio of crap to innovation still applies.
The author of this article makes another mistake: thinking that games will stop looking like each other with the advent of pixel shaders. Of course this is rediculous. I do believe that technology can enable new aspects of gameplay, but to think that pixel shaders are going to make people more creative is just plain wrong.
"the water effects used in Super Mario Sunshine, cel shading effects used in Zelda, or the rippling water effects on Dead or Alive 3."
The gamecube doesn't have shader hardware, it uses a fixed function approach with many texture stages. Granted, the flexibility afforded by a dozen or so texture stages is similar to simple pixel shader hardware but there are still fundamental differences (particularly in the ability to do texture indirection) that make real shaders far more flexible. The first two games mentioned above don't use shaders at all... this guy should do a bit more research.