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{{Needs Example}}
Matrices are one of the most powerful features of MTA [[OOP]]. We did have a presence of Matrices before with [[getElementMatrix]], but we were given an ugly disgusting table to play with. Now, with the new Matrix class, we can make and magically manipulate Matrices.
Matrices are one of the most powerful features of MTA [[OOP]]. We did have a presence of Matrices before with [[getElementMatrix]], but we were given an ugly disgusting table to play with. Now, with the new Matrix class, we can make and magically manipulate Matrices.
__TOC__
__TOC__
==Methods==
==Methods==
===create===
===create===
This is default constructor for the Matrix class and returns a Matrix object.
This is default constructor for the Matrix class and returns a Matrix object. You can instantiate a Matrix object in several ways, as described below.
 
<syntaxhighlight lang="lua">matrix Matrix ( Vector3 position[, Vector3 rotation] )</syntaxhighlight>
* '''position''': The position vector of the matrix
* '''rotation''': The rotation vector of the matrix
 


====Syntax====
<syntaxhighlight lang="lua">matrix Matrix ( Vector3 position, Vector3 rotation )</syntaxhighlight>
<syntaxhighlight lang="lua">matrix Matrix ( Matrix matrixToClone )</syntaxhighlight>
<syntaxhighlight lang="lua">matrix Matrix ( Matrix matrixToClone )</syntaxhighlight>
<syntaxhighlight lang="lua">matrix Matrix ( )</syntaxhighlight>
* '''matrixToClone''': A matrix you want to make a clone of
 
 
<syntaxhighlight lang="lua">matrix Matrix()</syntaxhighlight>
* You can call this method without parameters to initialize a zero matrix


=====Required Arguments=====
* '''position''': The position vector of the matrix
* '''rotation''': The rotation vector of the matrix
OR
* '''matrixToClone''': A matrix you want to instantiate a clone of
OR
* You can call this method without parameters to initialize a zero matrix.


===transformPosition===
===transformPosition===
This method transforms a given position vector using the Matrix.
This method transforms a given position vector using the Matrix.


====Syntax====
<syntaxhighlight lang="lua">Vector3 Matrix:transformPosition ( Vector3 position )</syntaxhighlight>
<syntaxhighlight lang="lua">Vector3 Matrix:transformPosition ( Vector3 position )</syntaxhighlight>
=====Required Arguments=====
* '''position''': The position vector you want to transform
* '''position''': The position vector you want to transform


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local desiredRelativePosition = Vector3(0, 5, 0) -- 5 meters front of player is a y = 5 vector
local desiredRelativePosition = Vector3(0, 5, 0) -- 5 meters front of player is a y = 5 vector
local matrix = player.matrix
local matrix = player.matrix
local newPosition = matrix.transformPosition(desiredRelativePosition)
local newPosition = matrix:transformPosition(desiredRelativePosition)
player.position = newPosition
player.position = newPosition
</syntaxhighlight>
</syntaxhighlight>
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This method returns the position vector of a given matrix.
This method returns the position vector of a given matrix.


====Syntax====
<syntaxhighlight lang="lua">Vector3 Matrix:getPosition()</syntaxhighlight>
<syntaxhighlight lang="lua">Vector3 Matrix:getPosition ( )</syntaxhighlight>


====Example====
====Example====
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===getRotation===
===getRotation===
This method returns the rotation vector of a given matrix.
<syntaxhighlight lang="lua">Vector3 Matrix:getRotation()</syntaxhighlight>
====Example====
This example prints the rotation of a random player.
<syntaxhighlight lang="lua">
local player = getRandomPlayer()
local matrix = player.matrix
local rotation = matrix:getRotation()
outputChatBox("rx: " .. rotation:getX() .. ", ry: " .. rotation:getY() .. ", rz:" .. rotation:getZ())
</syntaxhighlight>
===getForward===
===getForward===
===getRight===
===getRight===
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==Using Matrices==
==Using Matrices==
Say you wanted to create a bin - object 1337 - two units in front of a player. You don't want to manually do trigonometry and you don't want to play with the complicated tables. You just want to get the position two units in front of the player whilst taking into account the rotation of the player. You only need to use '''[[Matrix.getForward]]'''. '''[[Matrix.getPosition]]''' and '''[[getElementMatrix]]'''.  It's just:
Say you wanted to create a bin - object 1337 - two units in front of a player. You don't want to manually do trigonometry and you don't want to play with the complicated tables. You just want to get the position two units in front of the player whilst taking into account the rotation of the player. You only need to use '''[[Matrix#getForward|Matrix.getForward]]''', '''[[Matrix#getPosition|Matrix.getPosition]]''' and '''[[getElementMatrix]]'''.  It's just:
<syntaxhighlight lang="lua">
<syntaxhighlight lang="lua">
Object ( 1337, player.matrix.position + player.matrix.forward * 2 )
Object ( 1337, player.matrix.position + player.matrix.forward * 2 )
</syntaxhighlight>
If you wanted the opposite of matrix.forward you'll still use matrix.forward but you minus it instead of matrix.backward which doesn't exist. Same applies with matrix.right and matrix.up. To make the bin object appear behind a player:
<syntaxhighlight lang="lua">
Object ( 1337, player.matrix.position - player.matrix.forward * 2 )
</syntaxhighlight>
</syntaxhighlight>


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[[ru:Matrix]]
[[ru:Matrix]]
[[Category:OOP]]
[[Category:OOP]]
[[Category:Incomplete]]

Revision as of 18:47, 16 February 2018

Accessories-text-editor.png Script Example Missing Function Matrix needs a script example, help out by writing one.

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Matrices are one of the most powerful features of MTA OOP. We did have a presence of Matrices before with getElementMatrix, but we were given an ugly disgusting table to play with. Now, with the new Matrix class, we can make and magically manipulate Matrices.

Methods

create

This is default constructor for the Matrix class and returns a Matrix object. You can instantiate a Matrix object in several ways, as described below.

matrix Matrix ( Vector3 position[, Vector3 rotation] )
  • position: The position vector of the matrix
  • rotation: The rotation vector of the matrix


matrix Matrix ( Matrix matrixToClone )
  • matrixToClone: A matrix you want to make a clone of


matrix Matrix()
  • You can call this method without parameters to initialize a zero matrix


transformPosition

This method transforms a given position vector using the Matrix.

Vector3 Matrix:transformPosition ( Vector3 position )
  • position: The position vector you want to transform

Example

This example teleports a random player to a location 5 meters in front of him

local player = getRandomPlayer()
local desiredRelativePosition = Vector3(0, 5, 0) -- 5 meters front of player is a y = 5 vector
local matrix = player.matrix
local newPosition = matrix:transformPosition(desiredRelativePosition)
player.position = newPosition

getPosition

This method returns the position vector of a given matrix.

Vector3 Matrix:getPosition()

Example

This example prints the position of a random player.

local player = getRandomPlayer()
local matrix = player.matrix
local position = matrix:getPosition()
outputChatBox("x: " .. position:getX() .. ", y: " .. position:getY() .. ", z:" .. position:getZ())

getRotation

This method returns the rotation vector of a given matrix.

Vector3 Matrix:getRotation()

Example

This example prints the rotation of a random player.

local player = getRandomPlayer()
local matrix = player.matrix
local rotation = matrix:getRotation()
outputChatBox("rx: " .. rotation:getX() .. ", ry: " .. rotation:getY() .. ", rz:" .. rotation:getZ())

getForward

getRight

getUp

Using Matrices

Say you wanted to create a bin - object 1337 - two units in front of a player. You don't want to manually do trigonometry and you don't want to play with the complicated tables. You just want to get the position two units in front of the player whilst taking into account the rotation of the player. You only need to use Matrix.getForward, Matrix.getPosition and getElementMatrix. It's just:

Object ( 1337, player.matrix.position + player.matrix.forward * 2 )

If you wanted the opposite of matrix.forward you'll still use matrix.forward but you minus it instead of matrix.backward which doesn't exist. Same applies with matrix.right and matrix.up. To make the bin object appear behind a player:

Object ( 1337, player.matrix.position - player.matrix.forward * 2 )

Why not stick to the good ol' tables?

Say you'd like to get find the position underneath a vehicle. This is the position at any rotation. So if it was upside down, the Z value would be higher than the vehicle Z value. If the vehicle was the right way round, the Z value for underneath car would be less than the Z value for the car.

--
-- Instead of:
--
local matrix = getElementMatrix(vehicle)
local offX = 0 * matrix[1][1] + 0 * matrix[2][1] - 1 * matrix[3][1] + matrix[4][1]
local offY = 0 * matrix[1][2] + 0 * matrix[2][2] - 1 * matrix[3][2] + matrix[4][2]
local offZ = 0 * matrix[1][3] + 0 * matrix[2][3] - 1 * matrix[3][3] + matrix[4][3]

local pX, pY, pZ = getElementPosition(vehicle)
local positionBelow = {offX-pX, offY-pY, offZ-pZ}

--
-- You only have to do:
--
local positionBelow = vehicle.position - vehicle.matrix.up