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[EphemeralDream]

There are often times members of GAF, web sites, etc. will drop graphics terminology (technical or slang) that most people understand, but I'm part of the minority who doesn't and likely never will. I understand a lot of the newer terms used like depth of field, motion blur, bloom, etc. but not the words that have been used for years. I'm sure many answers are on the internet but here it would be more concise and perhaps it could help others in the process. Also please don't troll with your console allegiances or say how as a gamer I should really know these things by now. Some of these I do understand for the most part but would just need some elaboration:

My questions are organized into a few different areas and yeah I write too much. I would also appreciate it if people tried to answer in their own words rather than refer me to some wikipedia entry. Using images/video as example would be helpful though.

Spoiler

Hopefully someone replies

1. Resolution

Anamorphic widescreen/fake (?) widescreen – These two types are used in games and I assume one is better than the other but I don't know what differentiates them. I believe RE4 GC had widescreen but not the good kind where as the PS2 version had anamorphic widescreen.
What does a developer need to do to add widescreen so late in the process? - Support multiple assets?

Interlaced vs. Progressive – I understand how they both work but without having a progressive TV, I've never been able to see the difference. Are side-by-side image comparisons possible even if all monitors render progressively?

2. Frame Rate

30 FPS / 60 FPS / Frame Rate Drop – Discussions have gone on about frame rate for years and while I can notice really bad frame rate drops, I never took much notice of the “horrible” frame rate in SotC till all the posts on it about GAF. I also am not able to tell if a game is 60/30 fps just by playing it. Probably the only time I noticed was between the 30 FPS DDR Konamix for PS1 and the 60 FPS PS2 DDRs. Are there any sites which list the frame rates that games shoot for so I could look through my own library for examples?

Screen tearing - ??

3. Aliasing

Jaggies – I believe this is simply when the hard edges on either sprites or polygons are very visible which makes it appear to be cut out from everything else. Is there any other way to deal with jaggies aside from anti-aliasing/filters?

#xAA – What is the lowest amount of AA possible and what other downsides are there to higher powers of AA aside from needing more horsepower.

On the DS – I've seen angry complaints about the inability to do AA in DS games. So is all AA done through hardware rather than the game engine?

4.Graphical Style

2.5D – The usage of 3D models in the foreground with sprites used for background. Examples: NSMB, Maverick Hunter X, MMPU, etc. Correct? How was Donkey Kong Country done?

Cel-Shading – I know what this looks like of course but I'm curious as to how it's done. Also, does it require more power to achieve this look?

5.Other

Vaseline – I've taken this to mean large, blurry textures. Is this correct and why was the N64 such a big culprit?

Dithering – No idea

Ghosting – I believe this is when a fast-moving object leaves a trail. This is often the fault of the television but can the game also be at fault?

Frame Buffer – I know this has something to do with screen captures but how are these different than other ones?

 

[Srider]

Why do you bother?

 

[davepoobond]

widescreen clarification: 16:9 is standard widescreen. also known as 1.77:1. Anything greater than that (usually around 2.2:1) would be called animophic widescreen, and it just means its got a "bigger" picture feel to it.

screen tearing means that graphics appear to "tear" iirc.

2.5D is correct. its basically 3D in a 2D world.

dithering - decrease of quality in a picture due to bad rendering/saving of a picture/texture i believe.

ghosting - in all frankness, it works with the "frame rate" thing. LCD screens have "ghosting" issues because the screen doesn't refresh fast enough and it tricks your eyes into thinking that there's a "trail" left behind.


that's all i can really explain.

 

[Fantasmo]

Dithering - while I can't explain it technically, dithering is when there isn't enough color depth to properly display a mathematical special effect: explosions, smoke, smoke screen, color flashing, color blendings, etc.

Basically when something is dithered, you get "wrong" colors in areas.

An example: a smokey room that should be all kinds of grey, has green, red, and blue pixels and variants of any other color you can imagine within the area that's supposed to be all grey.

You can catch dithering in action in just about any 16-bit color depth game like (RE4 for GC), or really old porn jpgs :lol

 

[human5892]

I'll answer a few real quick-like:

Screen tearing - This is when one half of the screen refreshes faster than the other, resulting in a choppy line going down the image as the two halves reconcile each other. See God of War.

2.5D – The usage of 3D models in the foreground with sprites used for background. Examples: NSMB, Maverick Hunter X, MMPU, etc. Correct? How was Donkey Kong Country done?

You have it backwards, actually -- 2.5D is sprite foreground objects moving through 2D levels rendered with polygons. Donkey Kong Country is a purely sprite-based game that was made using a technique called ACM, where 3D models rendered on high-end computers were compressed down into sprites that the SNES hardware could handle.

Vaseline – I've taken this to mean large, blurry textures. Is this correct and why was the N64 such a big culprit?

The N64 had a miniscule texture cache and limited storage due to using carts, so developers could not fit in large amounts of texture data. Therefore, they were forced to use simple low-res textures that looked like ass most of the time.

Dithering – Usually, this is used in games that are running in low-color modes to try and resolve the difference in shading and color gradients. It results in an effect that looks like little crosshatches on the screen, or sometimes little black dots (see some areas in Zelda: Wind Waker, particularly during sunrise/sunset on the ocean).

Ghosting – This traditionally refers to what you see when playing a game on a monitor with a low refresh rate or response time, resulting in afterimages or blurring of fast-moving objects.

 

[Naked Snake]

widescreen clarification: 16:9 is standard widescreen. also known as 1.77:1. Anything greater than that (usually around 2.2:1) would be called animophic widescreen, and it just means its got a "bigger" picture feel to it..

Sorry, but no.

 

[M3wThr33]

Dithering is the art of mixing nearby colors to create a new one when looked at from a distance. (The newspaper does this to make grayscale)

 

[Srider]

Just don't correct their errors, then this thread can be the birthplace of all kinds of hilarity in the future.

Losing is winning!

 

[Fallout-NL]

widescreen clarification: 16:9 is standard widescreen. also known as 1.77:1. Anything greater than that (usually around 2.2:1) would be called animophic widescreen, and it just means its got a "bigger" picture feel to it.

To use the term anamorphic in videogaming has always been nonsense. It means that a movie has been shot using an anamorphic lense. It captures a wide image, but fits it on a narrow strip of film. You have to use a similar lense when projecting to get the proper image on screen.

Anyway, my 2 cents. No idea why you would use the term in videogaming.

 

[Branduil]

Anamorphic widescreen/fake (?) widescreen – Anamorphic widescreen is a screen that is wide, but it's wide because it wants to be, not because it can't control its weight. Fake widescreens are those weirdos who dress up like fat people using costumes even though they're not really fat.

Interlaced vs. Progressive – Progressive screens support more liberal social and economic policy. Interlaced screens have dialogues with international nations but lace all their dialogue with sarcasm, hence the term "inter(national dialogue)laced(with sarcasm)."
2. Frame Rate

Screen tearing - What you do to your screen the first time you accidentally click on a link that leads to furry art.

Jaggies – This is when your game is infested with fanboys of the Navy courtroom-based TV drama "JAG." For some reason the PS2 has an exceptionally large amount of JAG fanboys.

Cel-Shading – Because the cell processor is so powerful, it must be shaded to prevent its awesome power from blinding onlookers. The cel-shader is all the protects us from its blinding awesomeness.

Vaseline – Jars of this were given Nintendo fans at N64 launch so they could prepare themselves for the high-priced cartridge rapeage.

Ghosting – When people still lurk on a forum despite being banned.

Frame Buffer – The coolest game players around. They get their moniker from the fact that they always wear awesome sunglasses which they keep keenly buffed at all times.

 

[imastalker co.]

shaders?

 

[Chris Remo]

Anamorphic widescreen/fake (?) widescreen – Anamorphic widescreen is a screen that is wide, but it's wide because it wants to be, not because it can't control its weight. Fake widescreens are those weirdos who dress up like fat people using costumes even though they're not really fat.

Interlaced vs. Progressive – Progressive screens support more liberal social and economic policy. Interlaced screens have dialogues with international nations but lace all their dialogue with sarcasm, hence the term "inter(national dialogue)laced(with sarcasm)."
2. Frame Rate

Screen tearing - What you do to your screen the first time you accidentally click on a link that leads to furry art.

Jaggies – This is when your game is infested with fanboys of the Navy courtroom-based TV drama "JAG." For some reason the PS2 has an exceptionally large amount of JAG fanboys.

Cel-Shading – Because the cell processor is so powerful, it must be shaded to prevent its awesome power from blinding onlookers. The cel-shader is all the protects us from its blinding awesomeness.

Vaseline – Jars of this were given Nintendo fans at N64 launch so they could prepare themselves for the high-priced cartridge rapeage.

Ghosting – When people still lurk on a forum despite being banned.

Frame Buffer – The coolest game players around. They get their moniker from the fact that they always wear awesome sunglasses which they keep keenly buffed at all times.

:lol :lol :lol :lol

 

[Grayman]

vasaline could also be used when someone releases bullshots where everything looks blurred and shiny


2.5d i would use to describe doom/duke3d/wolfenstein. A seemingly 3d world that is rendered in 2d.

 

[alr1ght]

anamorphic widescreen:
The internal image rendered is widescreen (16:9)
If it were letterbox that 16:9 image would be "pasted" into a 4:3 image, mimicking widescreen, but no extra resolution.

 

[Grayman]

shaders?

used like a texture but is a script of effects.

like water or lava in the quake 3 engine is a shader.

A shader is a computer program used in 3D computer graphics to determine the final surface properties of an object or image. This often includes arbitrarily complex descriptions of light absorption, diffusion, texture mapping, reflection, refraction, shadowing, surface displacement and post-processing effects.

...In layman's terms, a shader answers the question (that the rendering program asks), "Given the locations of all the objects, all the lights, and the camera in a scene, what color should I draw this particular object at this particular location?"

 

[gblues]

Dithering is the art of mixing nearby colors to create a new one when looked at from a distance. (The newspaper does this to make grayscale)

Actually, no, that's halftoning. But dithering is similar.

Dithering is a technique for simulating continuous tones when there aren't enough colors available to accurately render the continuous tone. It's more obvious on older 256-color games, but you still see it in modern games when 32-bit textures are rendered with only 16-bit precision.

Screen tearing is a rendering artifact where the frame is displayed before it has finished rendering. Normally, a developer will time the frame switch to happen during the vertical blank period (a technique commonly called "vsync"). But if there's too much going on, a developer may go for a performance boost and just go as fast as possible. This improves the framerate at the cost of quality, which is why it gets brought up in framerate whoring threads.

Interlaced vs Progressive: an SD television is interlaced--this means the TV draws the even-numbered rows followed by the odd numbered rows. Only half the screen is being drawn at a given time. This causes small text to appear to flicker. A VGA computer monitor is progressive. The screen is drawn from top to bottom, one line after the next. Since the entire screen is drawn at once, the image is noticably sharper.

2.5D really covers any not-quite-3d technique. It covers both 3d-rendered-2d like Contra: Shattered Soldier and NSMB and almost-but-not-quite-3d games like Duke 3d and Doom.

#xAA: Larger numbers are better. The # is the factor by which the scene is rendered internally before it is downsampled to the actual screen resolution. The larger the factor, the more effective the anti-aliasing. BTW "aliasing" is the proper term for what is often referred to as "jaggies."

The "frame buffer" is a portion of video memory set aside for storing rendered frames to be displayed on the screen. A "frame buffer grab" is a screenshot taken directly from video memory, instead of photographed or captured via video capture hardware.

Anamorphic widescreen vs. "fake" widescreen: anamorphic lets the TV worry about rendering letterboxes, if necessary. "Fake" widescreen is so despised because developers basically draw the black bars manually, which means there's less screen resolution for the actual game.

Nathan

 

[Fallout-NL]

Still dont see why you would call that anamorphic widescreen, I thought the term referred to a technigue used in the film-industry.

 

[davepoobond]

Sorry, but no.

i just worded it wrong. fallout did a better job explaining it.

 

[Syb]

Grand Theft Auto 3 ghosts like shit on my LCDTV, yet both Vice City and San Andreas are A-Okay. Yup, thats my contribution.

 

[Ranger X]

Grand Theft Auto 3 ghosts like shit on my LCDTV, yet both Vice City and San Andreas are A-Okay. Yup, thats my contribution.

Go in the options (GTA3) and turn "trails" off.

 

[Dahbomb]

I don't speak graphics either, and there a lot of terms I am not too sure on:

HDR v.s. Bloom Lighting v.s. Ray Tracing

Aliasing v.s. Shimmering

Bumped v.s. Normal Mapping

2D v.s. 3D motion blur


There are many more but these are the ones in recent memory.

 

[Chris_C]

Not to derail the thread, but I've never fully understood why filmakers shoot in anamorphic widescreen. I understand it looks good in theatres, and I've heard it increases picture clarity on DVD's (though I don't know if this is true).

What really annoys me is the fact that I have a widescreen TV and I still can't have a lot of movies fill the screen because they're shot in anamorphic.

 

[EphemeralDream]

lol at the dithering in davepoobond's avatar. Thread complete.

Otherwise there are some excellent answers in here even if some contradict others. Keep them coming.

 

[sc0la]

anamorphic widescreen is still fake widescreen btw, the image sent in anamoprhic is still a 4:3 image iirc.

An anamorphic widescreen game is stil la 640x480 image, with a different pixel shape and field of view to accomodate being stretched.

Letterboxed widescreen is a 640x480 image with black bars which when zoomed to widescreen results in less pixels being displayed.

A true widescreen image is displayed in 16x9 ratio i.e. 1280x720

So to recap
Letterbox widescreen = Resident Evil 4 GC version
Anamorphic widescreen = Resident Evil 4 PS2 version
True widescreen = Resident Evil 5

Spoiler

or I will personally punch capcoms face

I am not sure if an HDTV/EDTV is capable of receiving a "850x480" imgae for a true widescreen 480p image. i.e. I am not yet convinced Wii can output a true widescreen image. (Not that it matters in the end 480p widescreen f-zero is the shit and its animorphic)

 

[Rud13inJapan]

lolz n00b

just kidding, I don't know either

 

[Tumalu]

anamorphic widescreen:
The internal image rendered is widescreen (16:9)
If it were letterbox that 16:9 image would be "pasted" into a 4:3 image, mimicking widescreen, but no extra resolution.

I was under the impression that anamorphic widescreen simply referred to discs that were designed to have their 720x480 image stretched to a 16x9 aspect ratio. On a non-widescreen they would have to be letter boxed though. On the other hand, the other type of widescreen (what's it called, "matted"?), was a 720x480 image with black bars on top and bottom that was designed to be stretched onto a 4x3 TV. Thus anamorphic would have better resolution since it's not wasting pixels at the top and bottom of the image - as stored on the DVD.

But even anamorphic widescreen should display in a letterbox mode with a 4:3 TV if your DVD player is set up properly. As far as I'm aware, there shouldn't be any difference between anamorphic and non- unless you're using a widescreen TV, in which case, non-anamorphic widescreen would get black bars on all 4 sides unless you used the zoom feature of the TV.

Am I just confusing terms here? Does anamorphic refer to something else? This is how I've always understood it.

 

[Syb]

Go in the options (GTA3) and turn "trails" off.

Wow, Woah. Never saw that there, VERY much appreciated, its now playable. What a useless option. :lol

 

[Ranger X]

Wow, Woah. Never saw that there, VERY much appreciated, its now playable. What a useless option. :lol

Was prolly implemented for anti-jaggies douches. At that time the press was all like "ohh, the PS2 doesn't do AA... etc". It is indeed useless and suck as an option since it was making the game look worse imo.

 

[sprocket]

Just do what everyone else does . Use the term NORMAL MAPPING a lot with out any knowledge what so ever of what it really is .

 

[Fallout-NL]

What really annoys me is the fact that I have a widescreen TV and I still can't have a lot of movies fill the screen because they're shot in anamorphic.

No thats simply because widescreens are 16:9, most modern movies, however are a bit wider than that, 2.35:1 (or something like that?)

Not to derail the thread, but I've never fully understood why filmakers shoot in anamorphic widescreen. I understand it looks good in theatres, and I've heard it increases picture clarity on DVD's (though I don't know if this is true).

My guess would be that 70mm film is more expensive than 35mm stock. The anamorphic lense allows you to shoot widescreen on regular stock (35mil) You can also do it with 16mm stock, that results in really grainy film though.

 

[EphemeralDream]

So from what I'm reading here, letterbox widescreen will have black bars on the top and bottom even if it is played on a widescreen television? However letterboxed is better than nothing as widescreen televisions would have a much more squished image if it is only 4:3 correct?

 

[Sinatar]

3. Aliasing

Jaggies – I believe this is simply when the hard edges on either sprites or polygons are very visible which makes it appear to be cut out from everything else. Is there any other way to deal with jaggies aside from anti-aliasing/filters?

Jaggies are what occur when a straight polygonal surface is rendered at an angle. The sufaces basically looks like a staircase, so what should be a straight line is jagged.

#xAA – What is the lowest amount of AA possible and what other downsides are there to higher powers of AA aside from needing more horsepower.

Anti Aliasing is another term for multisampling, basically rending the same object over top of itself over and over to cover the jaggies up. The x# in AA refers to how many times this occurs. The higher the AA # the more processing power is required to do it. It's a little more technical then that, but that should give you the jist of it.

Another term you might want to learn is Anisotropic Filtering or AF. Also measured as x# (like AA). This refers to a process that keeps textures looking crisp at a distance. Games without AF have a muddy or blurry look to things out at a distance, AF fixes this.

So from what I'm reading here, letterbox widescreen will have black bars on the top and bottom even if it is played on a widescreen television? However letterboxed is better than nothing as widescreen televisions would have a much more squished image if it is only 4:3 correct?

That is right, the black bars show up irregardless. Some TV's (like mine) have special zoom features to accomodate for this though so letterbox ends up looking almost as good as anamorphic.

 

[The Friendly Monster]

That is right, the black bars show up irregardless

That isn't a word. .

 

[sc0la]

So from what I'm reading here, letterbox widescreen will have black bars on the top and bottom even if it is played on a widescreen television? However letterboxed is better than nothing as widescreen televisions would have a much more squished image if it is only 4:3 correct?

Letterboxed widescreen will show black bars depending on whether you stretch or zoom the image, and according to the source image. If you zoom a LBW image that is "16x9" after matting you will only see the image, no black bars, but you are not getting the full 480 lines of resolution since you zoom a bit of it offscreen. See RE4 gamecube version which because of dithering, poor color depth, and LB widescreen looks fairly assy blown up on a widescreen hdtv.

The image only stretches if you want it to letterbox widescreen or 4:3 (both images are 4:3 btw). The only thing that it changes is whether you are cutting of black bars or part of the image.

If you stretch a letterbox widescreen image the black bars stay, but appear smaller as the are stretched further horizontally than they are vertically.

EDIT: that is unless of course you are talking about movies, in which case there will likely still be black bars no matter what the hell you do. :lol

 

[Vaporak]

used like a texture but is a script of effects.

Kinda but no. A shader is a rendering algorithm. Most uninformed like to use shader as a synonym for "special Effect" as a buzz word, but the truth is EVERYTHING is done with a shader on modern graphics hardware; no modern graphics hardware actually has a fixed function graphics pipeline anymore.

 

[Father_Mike]

Great Thread. Now some one awnser this?

I don't speak graphics either, and there a lot of terms I am not too sure on:

HDR v.s. Bloom Lighting v.s. Ray Tracing

Aliasing v.s. Shimmering

Bumped v.s. Normal Mapping

2D v.s. 3D motion blur


There are many more but these are the ones in recent memory.

 

[Vaporak]

I'm working on it, this is a big request.

 

[Pimpbaa]

I don't speak graphics either, and there a lot of terms I am not too sure on:

HDR v.s. Bloom Lighting v.s. Ray Tracing

Aliasing v.s. Shimmering

Bumped v.s. Normal Mapping

2D v.s. 3D motion blur


There are many more but these are the ones in recent memory.

Bloom lighting is basically a faked HDR. True HDR will apply the correct lighting to all surfaces and a more accurate effect if you look at a bright object (like the sun in a game)

Aliasing refers to the jagged edges you seen on the edges of everything you see in a game. anti-aliasing gets rid of this. Shimmering on the other hand happens when a texture goes far enough in the distance that the resolution that is being displayed can't properly show all the texels (pixels which make up a texture) of a particular texture and thus makes the texture look like a mess of shimmering looking pixels. A solution to this is either mip mapping (which can be blurry) or anisotropic filtering (looks the best but can have a large performance hit).

Bump and normal mapping I think are basically the same thing as far as I know. It's just another texture layer added to an object to tell the lighting system in the game how to project light on that object (usually this texture layer is taken from a much higher polygon model and added to a low poly model).

2D vs 3D motion blur? not sure what you are talking about there.

 

[reggieandTFE]

Yeah, what the hell is HDR?

 

[Pimpbaa]

Yeah, what the hell is HDR?

High dynamic range lighting.

 

[Bojangles]

Yeah, what the hell is HDR?

If you have a scene with a bright part, and a dark part, the bright looks really bright, and the dark looks really dark.

If you go from a bright area to a dark area, it looks REALLY dark, and slowly gets back to normal.
If you go from dark to bright, it looks really bright, then slowly goes back to normal.

like simulating the way your eyes adjust to light.

Edit: Screw around in PGR3 looking/walking in and out of the garage

 

[Vaporak]

Yeah, what the hell is HDR?

Here's the first part:


1: HDR vs Bloom vs Ray Tracing.
They have nothing to do with each other, so lets tackle them separately.

HDR: Stands for “High Dynamic Range” and in simple terms uses larger variables to store color data in the frame buffer (what gets sent to the display to be... displayed). In traditional rendering architectures the frame buffer is 32 bits in size per pixel, with the dimensions of the frame buffer being the resolution set by the renderer. These 32 bits are broken up into 4 groups of 1 Byte (1 Byte == 8 bits) and are then called the RGBA color channels. That stands for Red, Green, Blue, Alpha. The first three are what are called the color channels and the last one (alpha) is called the... alpha channel .

These 4 channels determine what the final color of the pixel will be. The color channels hold 256 different values of their respective color, so you have 256 shades of Red to work with for example. And the alpha channels holds 256 values of transparency. The alpha channel is used to allow part of an object behind the closest one to partially show through.

Now HDR just means that you use larger variables than 8 bits for the color channels. This is achieved in different ways, but the main goal is that you now have a much wider and more accurate color pallet to work with. The most popular way to do this is to used 16 bit floating point variables instead of the traditional 8 bit integers. Floating point numbers have the advantage of being able to hold a wide range of numbers, but also able to be more precise since they allow for a finite amount of decimal point accuracy (which integers don't have at all).

BLOOM: Light Bloom is a technique used to simulate a surface or light being brighter than the monitor can display. The reason it is often associated with HDR is that in the vast majority of cases, the monitor doesn't actually have the greater range or accuracy that HDR rendering provides so the developer adds light bloom to the HDR rendering path to add to the visual impact.

To do Light Bloom every frame has to be rendered twice. The first rendering of the frame is done at higher brightness levels than the follow rendering. Once the first rendering is done, the result is copyed and a blur filter is applied to the saved image. Then the scene is rendered at normal brightness levels. To create the final frame buffer sent to the display, the first (brighter and blurred) frame is blended on top of the second frame.

This creates the effect of light seeming to bleed further out and around objects than it normally would.

RAY TRACING: Has absolutely no relation to HDR or Bloom Lighting. Ray Tracing is a graphics algorithm (not to be confused with shader, Ray Tracing is a much more all encompassing algorithm than a shader) which determines final pixel color by simulating light in a geometric fashion.

Every light source is assumed to give off light in every direction, and that light can bounce a infinite number of times in the scene. Strait lines are used to track the light bounces until they intersect the virtual camera. The light rays take on different color attributes based on the properties of the geometry that they had previously intersected, and this light value is what is used to determine the final pixel color to be displayed.

A more common optimization to the Ray Tracing algorithm is called REVERSE RAY TRACING. It takes every pixel on the virtual camera (which corresponds to your frame buffer to be displayed) and projects a ray into the scene for each pixel. The rays then bounce off of geometry until they come to a light source, then the normal calculations are preformed.

 

[ZombieSupaStar]

Yeah, what the hell is HDR?

you know when you go to bed and turn out the lights and cant see shit right away? or when you wake up or go outside and squint on a real bright day?



its like that

 

[Bojangles]

Bloom:

Bloom is an effect where a bright light "spreads out" over an area larger than the original light source.

Think of a light sabre, how the glow is a sort of soft halo around the supposed light of the sword.

 

[Pimpbaa]

If you have a scene with a bright part, and a dark part, the bright looks really bright, and the dark looks really dark.

If you go from a bright area to a dark area, it looks REALLY dark, and slowly gets back to normal.
If you go from dark to bright, it looks really bright, then slowly goes back to normal.

like simulating the way your eyes adjust to light.

Edit: Screw around in PGR3 looking/walking in and out of the garage

That's a part of it. But it effects every surface in the game too. Like in oblivion for example, go into a town during dawn or dusk, and try it with and without HDR, the difference is huge (and beautiful).

 

[reggieandTFE]

Here's the first part:


1: HDR vs Bloom vs Ray Tracing.
They have nothing to do with each other, so lets tackle them separately.

HDR: Stands for “High Dynamic Range” and in simple terms uses larger variables to store color data in the frame buffer (what gets sent to the display to be... displayed). In traditional rendering architectures the frame buffer is 32 bits in size per pixel, with the dimensions of the frame buffer being the resolution set by the renderer. These 32 bits are broken up into 4 groups of 1 Byte (1 Byte == 8 bits) and are then called the RGBA color channels. That stands for Red, Green, Blue, Alpha. The first three are what are called the color channels and the last one (alpha) is called the... alpha channel .

These 4 channels determine what the final color of the pixel will be. The color channels hold 256 different values of their respective color, so you have 256 shades of Red to work with for example. And the alpha channels holds 256 values of transparency. The alpha channel is used to allow part of an object behind the closest one to partially show through.

Now HDR just means that you use larger variables than 8 bits for the color channels. This is achieved in different ways, but the main goal is that you now have a much wider and more accurate color pallet to work with. The most popular way to do this is to used 16 bit floating point variables instead of the traditional 8 bit integers. Floating point numbers have the advantage of being able to hold a wide range of numbers, but also able to be more precise since they allow for a finite amount of decimal point accuracy (which integers don't have at all).

BLOOM: Light Bloom is a technique used to simulate a surface or light being brighter than the monitor can display. The reason it is often associated with HDR is that in the vast majority of cases, the monitor doesn't actually have the greater range or accuracy that HDR rendering provides so the developer adds light bloom to the HDR rendering path to add to the visual impact.

To do Light Bloom every frame has to be rendered twice. The first rendering of the frame is done at higher brightness levels than the follow rendering. Once the first rendering is done, the result is copyed and a blur filter is applied to the saved image. Then the scene is rendered at normal brightness levels. To create the final frame buffer sent to the display, the first (brighter and blurred) frame is blended on top of the second frame.

This creates the effect of light seeming to bleed further out and around objects than it normally would.

RAY TRACING: Has absolutely no relation to HDR or Bloom Lighting. Ray Tracing is a graphics algorithm (not to be confused with shader, Ray Tracing is a much more all encompassing algorithm than a shader) which determines final pixel color by simulating light in a geometric fashion.

Every light source is assumed to give off light in every direction, and that light can bounce a infinite number of times in the scene. Strait lines are used to track the light bounces until they intersect the virtual camera. The light rays take on different color attributes based on the properties of the geometry that they had previously intersected, and this light value is what is used to determine the final pixel color to be displayed.

A more common optimization to the Ray Tracing algorithm is called REVERSE RAY TRACING. It takes every pixel on the virtual camera (which corresponds to your frame buffer to be displayed) and projects a ray into the scene for each pixel. The rays then bounce off of geometry until they come to a light source, then the normal calculations are preformed.

Holy poopy, are you a computer science major or a game designer?

 

[mr jones]

Here's the first part:


*Russian Calculus*

You do realize that unless someone has taken a course in computer graphics and animation that many folks won't have ANY idea what you just said. Plus, you have to say what the finished result is after applying effects like HDR and Bloom. Or why you won't see realtime raytracing in game software.

 

[Bojangles]

Bump mapping is a technique to give an object the appearance of more surface detail than it has in actual geometry.

Normal Mapping is the most straightforward of this:

Wikipedias example of the orange is good. It would be crazy to try and model all the detail on the surface of an orange with geometry (polygons). Instead, you use a sphere, and a "bump map".

When you light the sphere, you use the bump map (which is a special kind of texturemap) to represent how the angle of the "real" surface would be, instead of the angle you calculate with the actual geometry (which is a sphere).

Another example is Parallax mapping. Where normal mapping gives the illusion of surface detail via lighting differences, parallax mapping adds to that illusion by approximating depth.

 

[mr jones]

Bump mapping is a technique to give an object the appearance of more surface detail than it has in actual geometry.

Normal Mapping is the most straightforward of this:

Wikipedias example of the orange is good. It would be crazy to try and model all the detail on the surface of an orange with geometry (polygons). Instead, you use a sphere, and a "bump map".

When you light the sphere, you use the bump map (which is a special kind of texturemap) to represent how the angle of the "real" surface would be, instead of the angle you calculate with the actual geometry (which is a sphere).

Another example is Parallax mapping. Where normal mapping gives the illusion of surface detail via lighting differences, parallax mapping adds to that illusion by approximating depth.

OK, but what would be the visual difference of an orange model using Normal mapping, and an orange model using Parallax mapping.

Hell, even I don't know anything about that stuff. I always thought parallax had to do with multiple 2 dimensional backgrounds moving in the same direction at different speeds to similate depth...

 

[Ranger X]

Holy poopy, are you a computer science major or a game designer?

How is this technical stuff related with the game designer?