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@@ -9,7 +9,7 @@ Analyzing the similarities and the differences between the video and the 3D scen
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In order to be able to perform streaming, data needs to be segmented so that a client can request chunks of data and display it to the user while requesting another chunk.
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In video streaming, data chunks typically consist in a few seconds of video.
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In mesh streaming, some progressive mesh approaches encode a a base mesh that contains low resolution geometry and textures and different chunks that increase the resolution of the base mesh.
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In mesh streaming, some progressive mesh approaches encode a base mesh that contains low resolution geometry and textures and different chunks that increase the resolution of the base mesh.
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Otherwise, a mesh can also be segmented by separating geometry and textures, creating chunks that contain some faces of the model, or some textures.
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\subsection{Data persistence}
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@@ -283,8 +283,8 @@ Some other interfaces add 2 degrees of freedom to the previous one: the user doe
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This is typically the case of the video game \emph{nolimits 2: roller coaster simulator} which works with VR devices (oculus rift, HTC vive, etc\ldots) where the only interaction the user has is turning the head.
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Finally, most of the other interfaces give at least 5 degrees of freedom to the user: 3 being the coordinates of the position of the camera, and 2 being the angle (assuming the up vector is unchangeable, some interfaces might allow that giving a sixth degree of freedom).
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The most common controls are the trackball controls where the user rotate the object like a ball \href{https://threejs.org/examples/?q=controls#misc_controls_trackball}{(live example here)} and the orbit controls, which behave like the trackball controls but preserving the up vector \href{https://threejs.org/examples/?q=controls#misc_controls_orbit}{(live example here)}.
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Another popular way of controlling a free camera in a virtual environment is the first person controls \href{https://threejs.org/examples/?q=controls#misc_controls_pointerlock}{(live example here)}.
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The most common controls are the trackball controls where the user rotate the object like a ball \href{https://threejs.org/examples/?q=controls\#misc_controls_trackball}{(live example here)} and the orbit controls, which behave like the trackball controls but preserving the up vector \href{https://threejs.org/examples/?q=controls\#misc_controls_orbit}{(live example here)}.
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Another popular way of controlling a free camera in a virtual environment is the first person controls \href{https://threejs.org/examples/?q=controls\#misc_controls_pointerlock}{(live example here)}.
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These controls are typically used in shooting video games, the mouse rotates the camera and the keyboard is used to translate it.
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\subsection{Relationship between interface, interaction and streaming}
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