3.0 KiB
\[Category Packet{{packet|name=Camera oscillate|description=Begin camera oscillation|opcode=35|type=Fixed|length=4|revision=317}} == Camera oscillate ==
=== Description === Begins camera oscillation, which is implemented using a configurable sinusoidal oscillator to offset a specific degree of freedom.
=== Packet Structure ===
{| border=2 ! Data type ! Description |- | [[Data Types#Standard data types|Byte]] | Parameter (camera X, Z, Y, yaw, pitch) |- |
\[Data Types\#Standard data types\|Byterandomization |- | Data Types#Standard data types | Amplitude |- | Data Types#Standard data types | Frequency (scaled by 100) |- |}
=== Other Information === The oscillate event enables the client to oscillate one of 5 of it's position parameters, i.e. corresponding to the camera's degrees of freedom; parameters 0, 1, and 2 refer to the location of the camera, while 3 and 4 deal with the camera's orientation. Together, these enable complex effects involving manipulation of the camera position to give rise to simulated earth-quakes and camera shock. {| border=2 ! Parameter ! Description |- | 0 | Camera location along world X axis (a horizontal axis, aligned with map grid X) |- | 1 | Camera location along world Z axis (vertical axis) |- | 2 | Camera location along world Y axis (a horizontal axis, aligned with map grid Y) |- | 3 | Camera orientation in world X plane w.r.t. world Z axis, i.e. yaw |- | 4 | Camera orientation in world Z plane w.r.t. world X axis, i.e. pitch |- |} Note there is no built-in way to manipulate camera roll, as this is not one of the camera's degrees of freedom.
=== What it's doing === Every time the world is rendered, each camera parameter that is enabled for oscillation is offset by a value computed as follows: {| border=2 ! Calculation ! Formula |- | Delta | (int) ((Math.random() * (double) (jitter * 2 + 1) - (double) jitter) + Math.sin((double) phase * ((double) frequency / 100D)) * (double) amplitude); |- |} Each parameter's phase accumulator (phase) is incremented by 1 each logic update.
=== Parameter === The offset itself is detailed as follows for each parameter: {| border=2 ! Parameter ! Action |- | 0 | camera_x += delta |- | 1 | camera_z += delta |- | 2 | camera_y += delta |- | 3 | camera_yaw = camera_yaw + delta & 0x7ff; |- | 4 | camera_pitch += delta |- |} Note that the camera's yaw is corrected modulo 0x7ff, or 2048, which is equivalent to 2{{{pi}}} radians in Jagex's binary angle system. This is not done to the camera pitch, which is instead clamped (see below).
=== Note === For oscillating the camera pitch, clamping is done to ensure the angle not out of bounds: {| border=2 |- |if (camera_pitch < 128) then camera_pitch = 128 |- |if (camera_pitch > 383) then camera_pitch = 383 |- |} This is do to Jagex restricting the possible range of orientations the camera may take.