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sketchpunk/Vec3.js

Last active February 11, 2023 02:47
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Vector 3 Allocator with Mutable Slices
Raw
_test.js
const alloc = new Vec3Allocator( 3 );
alloc.push( [1,1,1] ); // idx 0
alloc.push( [2,2,2] ); // idx 1
alloc.push( [3,3,3] ); // idx 2
alloc.setAt( 2, [5,5,5] ); // Modify 3rd Vec3
alloc.resize( 4 ); // Resize to hold 4 Vec3, [0,0,0]
// Get Mutable Slice
const vmut = alloc.getMut( 0 ); // [1,1,1]
vmut[ 1 ] = 77; // [1,77,1]
// Get Mutable Vec3 Array
const v = alloc.getVec3( 1 ); // [2,2,2]
v .add( [10,10,10] ) // [12,12,12]
.scale( 0.5 ) // [6,6,6]
.x += 2 // [8,6,6]
console.log( 'Array', alloc.toArray() );
// [1, 77, 1, 8, 6, 6, 5, 5, 5, 0, 0, 0]
console.log( 'From Vec3 Like', new Vec3( [1,2,3] ) );
console.log( 'Set Components', new Vec3( 4, 5, 6 ) );
console.log( 'Mutable Slice', new Vec3( alloc.arrayBuffer, 2 ) ); // [5,5,5]
Raw
Vec3.js
class Vec3 extends Float32Array{
constructor( arg0=null, arg1=null, arg2=null ){
// Slice of an existing Array Buffer
if( arg0 instanceof ArrayBuffer && typeof arg1 === 'number' ){
super( arg0, arg1 * 3 * 4, 3 );
}else{
super( 3 );
// First Argument is a vector3 like
if( ( Array.isArray( arg0 ) || arg0 instanceof Float32Array ) && arg0.length === 3 ){
this.set( arg0 );
// Setting XYZ
}else if( typeof arg0 === 'number' && typeof arg1 === 'number' && typeof arg2 === 'number' ){
this[ 0 ] = arg0;
this[ 1 ] = arg1;
this[ 2 ] = arg2;
}
}
}
get x(){ return this[ 0 ]; }
get y(){ return this[ 1 ]; }
get z(){ return this[ 2 ]; }
set x( v ){ this[ 0 ] = v; }
set y( v ){ this[ 1 ] = v; }
set z( v ){ this[ 2 ] = v; }
add( v ){
this[ 0 ] += v[ 0 ];
this[ 1 ] += v[ 1 ];
this[ 2 ] += v[ 2 ];
return this;
}
scale( s ){
this[ 0 ] *= s;
this[ 1 ] *= s;
this[ 2 ] *= s;
return this
}
}
Raw
Vec3Allocator.js
class Vec3Allocator{
// #region MAIN
_buf = null; // Float32Array Buffer
_capacity = 0; // Max vecs possible
_size = 0; // Current vec count
_autoResize = 0; // How many vecs to auto resize allocator
_idx = 0;
constructor( size=10 ){
this.resize( size );
}
// #endregion
// #region GETTERS
get size(){ return this._size; }
get byteSize(){ return this._buf.byteLength; }
get arrayBuffer(){ return this._buf.buffer; }
toArray(){ return Array.from( this._buf ); }
// #endregion
// #region METHODS
push( v ){
if( this._size >= this._capacity ){ console.log( 'Vec3Allocator at capacity' ); return this; }
this._buf.set( v, this._idx ); // Copy contents to buffer, V must be a [0,0,0] of some kind.
this._size += 1; // Extra Vec
this._idx += 3; // Move Buffer Index by 3 Floats = 1 Vec3
return this;
}
setAt( idx, v ){
if( idx >= this._capacity ){ console.log( 'GetMut: Index out of bounds' ); return this; }
this._buf.set( v, idx * 3 );
return this;
}
getMut( idx ){
if( idx >= this._capacity ){ console.log( 'GetMut: Index out of bounds' ); return null; }
return new Float32Array( this._buf.buffer, idx * 3 * 4, 3 ); // vecIndex * 3 Float * 4Byte Per Float
}
getVec3( idx ){
if( idx >= this._capacity ){ console.log( 'GetVec3: Index out of bounds' ); return null; }
return new Vec3( this._buf.buffer, idx ); // vecIndex * 3 Float * 4Byte Per Float
}
// Resize buffer allocation
resize( size=0 ){
if( size > this._capacity ){
const newBuf = new Float32Array( size * 3 ); // Create new buffer
if( this._buf ) newBuf.set( this._buf ); // Copy old buffer contents
this._buf = newBuf;
this._capacity = size;
}
return this;
}
// #endregion
}
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