Difference between revisions of "Category:LSL Vector"

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Each element can be accessed individually by appending .x, .y, or .z to the variable name.   
Each element can be accessed individually by appending .x, .y, or .z to the variable name.   


<lsl>vector vec;
<syntaxhighlight lang="lsl2">
float x = vec.x;
vector vec = <1, 2, 3>;
float y = vec.y;
float x = vec.x; // 1.0
float z = vec.z;</lsl>
float y = vec.y; // 2.0
float z = vec.z; // 3.0
</syntaxhighlight>
 
Note that components can be only accessed with vector variables. Attempting to access the components of a vector literal or a return value from a function is illegal.
<syntaxhighlight lang="lsl2">
// These are not valid component accesses
float f1 = <0, 1, 2>.z;
float f2 = llGetScale().x;
</syntaxhighlight>


===Uses===
===Uses===
Vectors can be used to hold the following:
Vectors are often used for...
* {{LSLGC|Movement|Position}}: x, y and z are in metres.
* {{LSLGC|Movement|Position}}: x, y, and z are in metres.
* {{LSLGC|Movement|Velocity}}: x, y and z represent speeds.
* {{LSLGC|Movement|Velocity}}: x, y, and z are in meters per second.
* {{LSLGC|Color|Colour}}: Red is x, Green is y and Blue is z.
* {{LSLGC|Color|Colour}}: x is Red, y is Green, and z is Blue.


===Operators===
===Operators===
Vectors support the following operations:
Vectors support the following operations:
* Addition, Operator "+"
==== Addition, Operator "+" ====
* Subtraction, Operator "-"
<syntaxhighlight lang="lsl2">
* Multiplication (Dot Product), Operator "*"
vector v = <1, 2, 3> + <0.5, 0.0, 3>; // <1.5, 2.0, 6.0>
* Cross Product, Operator "%"
</syntaxhighlight>
 
==== Subtraction, Operator "-" ====
<syntaxhighlight lang="lsl2">
vector v = <1, 1, 1> - <0.5, 0.0, 3>; // <0.5, 1.0, -2.0>
</syntaxhighlight>
 
==== Dot Product, Operator "*" ====
<syntaxhighlight lang="lsl2">
float f = <9, 2, 7> * <4, 8, 10>; // 122.0
</syntaxhighlight>
 
==== Cross Product, Operator "%" ====
<syntaxhighlight lang="lsl2">
vector v = <2, 3, 4> % <5, 6, 7>; // <-3, 6, -3>
</syntaxhighlight>
 
==== Scalar ====
A vector can be multiplied or divided by a [[Float]] or [[Integer]] to scale it.
 
Each component of the vector will be multiplied or divided by the same value.
<syntaxhighlight lang="lsl2">
vector v = <1, 2, 3> * 1.5; // <1.5, 3.0, 4.5>
vector v = <1, 2, 3> / 1.5; // <0.666667, 1.333333, 2.000000>
</syntaxhighlight>


==== Rotation ====
A vector can be multiplied or divided by a [[Quaternion]] to rotate it.
A vector can be multiplied or divided by a [[Quaternion]] to rotate it.
<syntaxhighlight lang="lsl2">
// 45-degree rotation around the Z (up) axis
rotation r = llEuler2Rot(<0, 0, 45> * DEG_TO_RAD);
// Vector whose direction is 1 meter to the east
vector v = <1, 0, 0>;
// Vector whose direction is north-east
vector rotated = v * r; // <0.707107, 0.707107, 0.000000>


===Example===
// Vector whose direction is south-east
<lsl>vector test=<1.0, 2.0, 3.0>;
// (division performs a rotation in the opposite direction)
llOwnerSay((string)test.z); // Outputs 3.0</lsl>
vector rotated = v / r; // <0.707107, -0.707107, 0.000000>
</syntaxhighlight>


===Useful Snippets===
===Useful Snippets===
<lsl>integer IsVector(string s)
Check whether a string value is a valid vector:
<syntaxhighlight lang="lsl2">integer IsVector(string s)
{
{
     list split = llParseString2List(s, [" "], ["<", ">", ","]);
     list split = llParseString2List(s, [" "], ["<", ">", ","]);
     if(llGetListLength(split) != 7)//we must check the list length, or the next test won't work properly.
     if(llGetListLength(split) != 7)//we must check the list length, or the next test won't work properly.
         return 0;
         return FALSE;
     return !((string)((vector)s) == (string)((vector)((string)llListInsertList(split, ["-"], 5))));
     return !((string)((vector)s) == (string)((vector)((string)llListInsertList(split, ["-"], 5))));
     //it works by trying to flip the sign on the Z element of the vector,
     //it works by trying to flip the sign on the Z element of the vector,
Line 42: Line 87:
     //if the vector was already broken then the sign flip will have no affect and the values will match
     //if the vector was already broken then the sign flip will have no affect and the values will match
     //we cast back to string so we can catch negative zero which allows for support of ZERO_VECTOR
     //we cast back to string so we can catch negative zero which allows for support of ZERO_VECTOR
}//Strife Onizuka</lsl>
}//Strife Onizuka</syntaxhighlight>

Latest revision as of 16:01, 15 October 2023

Vector

A vector is a data type that contains a set of three float values.

Components

Each element can be accessed individually by appending .x, .y, or .z to the variable name. 

vector vec = <1, 2, 3>;
float x = vec.x; // 1.0
float y = vec.y; // 2.0
float z = vec.z; // 3.0

Note that components can be only accessed with vector variables. Attempting to access the components of a vector literal or a return value from a function is illegal. 

// These are not valid component accesses
float f1 = <0, 1, 2>.z;
float f2 = llGetScale().x;

Uses

Vectors are often used for...

  • Position: x, y, and z are in metres.
  • Velocity: x, y, and z are in meters per second.
  • Colour: x is Red, y is Green, and z is Blue.

Operators

Vectors support the following operations:

Addition, Operator "+"

vector v = <1, 2, 3> + <0.5, 0.0, 3>; // <1.5, 2.0, 6.0>

Subtraction, Operator "-"

vector v = <1, 1, 1> - <0.5, 0.0, 3>; // <0.5, 1.0, -2.0>

Dot Product, Operator "*"

float f = <9, 2, 7> * <4, 8, 10>; // 122.0

Cross Product, Operator "%"

vector v = <2, 3, 4> % <5, 6, 7>; // <-3, 6, -3>

Scalar

A vector can be multiplied or divided by a Float or Integer to scale it.

Each component of the vector will be multiplied or divided by the same value. 

vector v = <1, 2, 3> * 1.5; // <1.5, 3.0, 4.5>
vector v = <1, 2, 3> / 1.5; // <0.666667, 1.333333, 2.000000>

Rotation

A vector can be multiplied or divided by a Quaternion to rotate it. 

// 45-degree rotation around the Z (up) axis
rotation r = llEuler2Rot(<0, 0, 45> * DEG_TO_RAD);

// Vector whose direction is 1 meter to the east
vector v = <1, 0, 0>;

// Vector whose direction is north-east
vector rotated = v * r; // <0.707107, 0.707107, 0.000000>

// Vector whose direction is south-east
// (division performs a rotation in the opposite direction)
vector rotated = v / r; // <0.707107, -0.707107, 0.000000>

Useful Snippets

Check whether a string value is a valid vector: 

integer IsVector(string s)
{
    list split = llParseString2List(s, [" "], ["<", ">", ","]);
    if(llGetListLength(split) != 7)//we must check the list length, or the next test won't work properly.
        return FALSE;
    return !((string)((vector)s) == (string)((vector)((string)llListInsertList(split, ["-"], 5))));
    //it works by trying to flip the sign on the Z element of the vector,
    //if it works or breaks the vector then the values won't match.
    //if the vector was already broken then the sign flip will have no affect and the values will match
    //we cast back to string so we can catch negative zero which allows for support of ZERO_VECTOR
}//Strife Onizuka

Subcategories

This category has the following 2 subcategories, out of 2 total.

D

V

Pages in category "LSL Vector"

The following 6 pages are in this category, out of 6 total.

T

V

Z

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