BVH

Classes

• BVH

Bounding Volume Hierarchy. Stores unsigned integer values at leaves, these are typically IDs or Index values. Highly optimized both in terms of memory usage and CPU. Most of the code is inlined for speed. No allocation are performed during usage (except for growing the tree capacity). RAM usage: 40 bytes per node, compared with V8s per-object allocation size of 80 bytes

Constants

• COLUMN_USER_DATA : number

A non-leaf node have both CHILD_1 and CHILD_2 set, when CHILD_1 is not set - it's a leaf node So we can utilize space of CHILD_2 to store USER_DATA, hence there is overlap in schema

• NULL_NODE : number

• CAPACITY_GROW_MULTIPLIER : number

• CAPACITY_GROW_MIN_STEP : number

• ELEMENT_WORD_COUNT : number

How many words are used for a single NODE in the tree One "word" is 4 bytes for the sake of alignment

• INITIAL_CAPACITY : number

How many nodes can be stored in the newly constructed tree before allocation needs to take place

• NODE_CAPACITY_LIMIT : number

Tree can not contain more than this number of nodes

BVH

Bounding Volume Hierarchy. Stores unsigned integer values at leaves, these are typically IDs or Index values. Highly optimized both in terms of memory usage and CPU. Most of the code is inlined for speed. No allocation are performed during usage (except for growing the tree capacity). RAM usage: 40 bytes per node, compared with V8s per-object allocation size of 80 bytes

Kind: global class
See: https://blog.dashlane.com/how-is-data-stored-in-v8-js-engine-memory

• BVH
  • .data_buffer ⇒ ArrayBuffer
  • .data_float32 ⇒ Float32Array
  • .root ⇒ number
  • .root
  • .size ⇒ number
  • .node_capacity ⇒ number
  • .node_capacity
  • .isBVH : boolean
  • .trim()
  • .allocate_node() ⇒ number
  • .release_node(id)
  • .node_is_leaf(id) ⇒ boolean
  • .node_get_user_data(id) ⇒ number
  • .node_set_user_data(id, value)
  • .node_get_child1(id) ⇒ number
  • .node_set_child1(node, child1)
  • .node_get_child2(id) ⇒ number
  • .node_set_child2(node, child2)
  • .node_get_parent(id) ⇒ number
  • .node_set_parent(node, parent)
  • .node_get_height(id) ⇒ number
  • .node_set_height(id, height)
  • .node_get_aabb(id, result)
  • .node_set_aabb(id, aabb)
  • .node_move_aabb(id, aabb)
  • .node_set_aabb_primitive(id, x0, y0, z0, x1, y1, z1)
  • .node_get_surface_area(id) ⇒ number
  • .node_get_combined_surface_area(index_a, index_b) ⇒ number
  • .node_set_combined_aabb(destination, index_a, index_b)
  • .insert_leaf(leaf) ⇒ void
  • .remove_leaf(leaf) ⇒ void
  • .node_assign_children(parent, child_1, child_2)
  • .node_assign_children_only(parent, child_1, child_2)
  • .release_all()
  • .traverse(callback, [ctx])
  • .collect_nodes_all(destination, destination_offset) ⇒ number
  • .swap_nodes(a, b) ⇒ boolean

bvH.data_buffer ⇒ ArrayBuffer

Access raw data Useful for serialization If you intend to modify the data directly - make sure you fully understand the implications of doing so

Kind: instance property of BVH

bvH.data_float32 ⇒ Float32Array

Kind: instance property of BVH

bvH.root ⇒ number

Kind: instance property of BVH

bvH.root

Make sure you understand what you're doing before using this

Kind: instance property of BVH

Param	Type
v	number

bvH.size ⇒ number

Number of used nodes. Note that this is not the same as number of live nodes Is the same as number of live nodes if compaction was performed recently

Kind: instance property of BVH

bvH.node_capacity ⇒ number

Kind: instance property of BVH

bvH.node_capacity

Kind: instance property of BVH

Param	Type
v	number

bvH.isBVH : boolean

Used for type checking

Kind: instance property of BVH
Read only: true

bvH.trim()

Trim allocated memory region to only contain allocated nodes

Kind: instance method of BVH

bvH.allocate_node() ⇒ number

Kind: instance method of BVH

bvH.release_node(id)

Release memory used by the node back into the pool NOTE: Make sure that the node is not "live" (not attached to the hierarchy), otherwise this operation may corrupt the tree

Kind: instance method of BVH

Param	Type
id	number

bvH.node_is_leaf(id) ⇒ boolean

Kind: instance method of BVH

Param	Type
id	number

bvH.node_get_user_data(id) ⇒ number

Kind: instance method of BVH

Param	Type
id	number

bvH.node_set_user_data(id, value)

Kind: instance method of BVH

Param	Type
id	number
value	number

bvH.node_get_child1(id) ⇒ number

Kind: instance method of BVH

Param	Type
id	number

bvH.node_set_child1(node, child1)

Kind: instance method of BVH

Param	Type
node	number
child1	number

bvH.node_get_child2(id) ⇒ number

Kind: instance method of BVH

Param	Type
id	number

bvH.node_set_child2(node, child2)

Kind: instance method of BVH

Param	Type
node	number
child2	number

bvH.node_get_parent(id) ⇒ number

Kind: instance method of BVH

Param	Type
id	number

bvH.node_set_parent(node, parent)

Kind: instance method of BVH

Param	Type
node	number
parent	number

bvH.node_get_height(id) ⇒ number

Kind: instance method of BVH

Param	Type
id	number

bvH.node_set_height(id, height)

Kind: instance method of BVH

Param	Type
id	number
height	number

bvH.node_get_aabb(id, result)

Kind: instance method of BVH

Param	Type
id	number
result	Array.<number> | Float32Array

bvH.node_set_aabb(id, aabb)

Kind: instance method of BVH

Param	Type
id	number
aabb	Array.<number> | ArrayLike.<number> | AABB3

bvH.node_move_aabb(id, aabb)

Kind: instance method of BVH

Param	Type
id	number
aabb	Array.<number>

bvH.node_set_aabb_primitive(id, x0, y0, z0, x1, y1, z1)

Kind: instance method of BVH

Param	Type
id	number
x0	number
y0	number
z0	number
x1	number
y1	number
z1	number

bvH.node_get_surface_area(id) ⇒ number

Kind: instance method of BVH

Param	Type
id	number

bvH.node_get_combined_surface_area(index_a, index_b) ⇒ number

Kind: instance method of BVH

Param	Type
index_a	number
index_b	number

bvH.node_set_combined_aabb(destination, index_a, index_b)

Kind: instance method of BVH

Param	Type
destination	number
index_a	number
index_b	number

bvH.insert_leaf(leaf) ⇒ void

Kind: instance method of BVH

Param	Type
leaf	number

bvH.remove_leaf(leaf) ⇒ void

NOTE: Leaf node is not released, make sure to call #release_node separately when you no longer need the leaf node

Kind: instance method of BVH

Param	Type
leaf	number

bvH.node_assign_children(parent, child_1, child_2)

Utility method for assigning both children at once Children must be valid nodes (non-null)

Kind: instance method of BVH

Param	Type
parent	number
child_1	number
child_2	number

bvH.node_assign_children_only(parent, child_1, child_2)

Utility method for assigning both children at once Children must be valid nodes (non-null) Does not update bounds.

Kind: instance method of BVH

Param	Type
parent	number
child_1	number
child_2	number

bvH.release_all()

Release all nodes, this essentially resets the tree to empty state NOTE: For performance reasons, released memory is not reset, this means that attempting to access cleared nodes' memory will yield garbage data

Kind: instance method of BVH

bvH.traverse(callback, [ctx])

Kind: instance method of BVH

Param	Type
callback	function
[ctx]	*

bvH.collect_nodes_all(destination, destination_offset) ⇒ number

Kind: instance method of BVH

Param	Type
destination	Array.<number>
destination_offset	number

bvH.swap_nodes(a, b) ⇒ boolean

Swap two nodes in memory

Kind: instance method of BVH

Param	Type
a	number
b	number

COLUMN_USER_DATA : number

A non-leaf node have both CHILD_1 and CHILD_2 set, when CHILD_1 is not set - it's a leaf node So we can utilize space of CHILD_2 to store USER_DATA, hence there is overlap in schema

Kind: global constant
Read only: true

NULL_NODE : number

Kind: global constant

CAPACITY_GROW_MULTIPLIER : number

Kind: global constant
Read only: true

CAPACITY_GROW_MIN_STEP : number

Kind: global constant
Read only: true

ELEMENT_WORD_COUNT : number

How many words are used for a single NODE in the tree One "word" is 4 bytes for the sake of alignment

Kind: global constant
Read only: true

INITIAL_CAPACITY : number

How many nodes can be stored in the newly constructed tree before allocation needs to take place

Kind: global constant
Read only: true

NODE_CAPACITY_LIMIT : number

Tree can not contain more than this number of nodes

Kind: global constant