Editing Hall of Mirrors

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The '''Hall of Mirrors''' effect is a rendering [[glitch]] present in many games, including ''[[Halo 3]]''. The glitch occurs when nothing is rendered to a particular region of the screen.

== Description ==
When a video game, such as ''Halo 3'', renders a 3D animation, it does so by generating frames of animation. Once the frame of animation has been created, it is then displayed on the screen -- specifically, it is drawn over the previous frame, covering it.

Sometimes, however, when a frame of 3D animation is rendered, nothing -- not even a skybox -- is rendered to a particular region of the screen. This results in parts of the affected frame being transparent. When the new frame is then drawn over the previous frame, parts of the previous frame show through. In nearly all games, this can result in a "hall of mirrors" or "afterimage" effect; if, in ''Halo 3'', it occurs on Player 2's screen during split-screen gameplay, then parts of Player 1's screen will appear on Player 2's screen.

When playing a [[Campaign]] or [[Multiplayer]] level, if a player can see outside the level -- that is, if they can see the void surrounding the level -- then they will see the hall of mirrors effect. However, when saving a screenshot or showing a Campaign [[Theater|film]], the effect is replaced with a solid color (usually sky blue in Multiplayer or off-white in Campaign). Furthermore, after taking a screenshot, the hall of mirrors effect sometimes shows part of the game's GUI (e.x. parts of the keyboard dialog box that is used to type a screenshot's name and description).

==Explanation==
To be more specific, the frames of animation are created by the rendering engine and stored in a [[Wikipedia:Framebuffer|framebuffer]]. The framebuffer is basically a storage area for frame data. When a frame is displayed, it is sent to the framebuffer.

The hall of mirrors effect results from the fact that the framebuffer is not cleared between frames.{{fact}} That is, the data from the previous frame is not deleted from the framebuffer before the next frame is drawn, so if the next frame has transparent regions, then the un-deleted data from the previous frame will show through.

There is also an explanation for the phenomenon that occurs when the hall of mirrors effect is seen during split-screen gameplay. If the same framebuffer was used for each of the split screens, then Player 1's screen would show through any transparent areas on Player 2's screen, because Player 2's screen is effectively drawn over Player 1's.{{fact}}
<!-- I'm not too sure about this, though they coulda used a virtual framebuffer? I don't get hardware. - DavidJCobb 07/28/2009 -->

==Seeing the Hall of Mirrors Effect==
There are a variety of ways to view the effect. Any time a player gets outside of the map or sees a gap in the level geometry, they may see the effect.

If [[Pan Cam]] is used to get outside of a level's boundaries, then the hall of mirrors effect is almost guaranteed to appear.

===Campaign===
====The Storm====
Start [[The Storm (Level)|The Storm]] at '''Rally Point Alpha''' on Co-op.

During the part with the [[Scarab Tank]]s, get two players on a Mongoose, and have them drive against a door <!-- which door? --> and the passenger to alight. <!-- what? --> If done correctly, the game will freeze for 10 seconds. The Scarab will disappear, and if you go to the door, you will see the hall of mirrors effect.

====The Covenant====
At the beginning of [[The Covenant (Level)|The Covenant]], after taking out the (normal) [[Wraith]], if you climb up the surface of the tower you are supposed to enter, you will find a rift in the snow that shows the hall of mirrors effect.

Another hall of mirrors effect occurs in this level. Start the level at '''Rally Point Alpha'''. Get into a [[Hornet]] and fly to the second tower. Look directly at it and hover down to the left. You will be facing a ledge; fly towards it. Park the Hornet onto the longest ledge, and face the rock wall. Turn left and move forward to a crack in the rock. When you look into it, you will see the hall of mirrors effect.

The glitch can also be seen when the [[Time Travel Glitch]] is performed.

====Halo====
Start [[Halo (Halo 3 Level)|Halo]] at '''Rally Point Alpha''' on [[Co-op]], so that you begin right after the part where you kill [[343 Guilty Spark]]. One player should move forwards and kill the [[Flood]] forces ahead; the other one should remain where they spawned. The stationary player should turn and look behind them. They will see two doors; they need to go to the bottom of the one on the left, and look straight up. There will be a small crack that displays the hall of mirrors effect.

===Multiplayer===
====Isolation====
:''These instructions need to be rewritten in terms of the default, unmodified Isolation, if possible.''
On a variant of the multiplayer map [[Isolation]], called "A Base", the glitch can be seen on the outer wall. If you venture outside the base and past the [[Mongoose]], look at your feet while sticking to the wall. So far along, your feet will start to float, like you are falling. Start to crouch and you will start to fall. Carry on crouching until you hit the grass. If you turn around so you are parallel to the wall, you will see the hall of mirrors effect.

====Sandtrap====
The glitch can be done in [[Sandtrap]] when in [[Forge]]. Go into Edit Mode, and fly into the chasm-like structure and face the high dunes that cover up the barrier. Look right, and move forward into the indention of top of the wall just below the ledge and zoom in. You should see the hall of mirrors effect here.

== External Links ==
*[http://www.youtube.com/watch?v=XDc5Pk6jIEY '''YouTube:''' FTWTF Funtage]
**This video, which was featured in [http://www.bungie.net/News/content.aspx?type=news&cid=21900 a Bungie.net news article], shows the hall of mirrors effect. The effect, which happens when a player lags beneath the ground, can be seen from [http://www.youtube.com/watch?v=XDc5Pk6jIEY#t=3m51s three minutes and fifty-one seconds into the video (3:51)] to four and a half minutes into the video (4:30).
[[Category:Glitches]]
[[Category:Halo 3 Glitches]]