{clone, typedArraySupport} = require './world_utils' Vector = require './vector' if typedArraySupport FloatArrayType = Float32Array # Better performance than Float64Array bytesPerFloat = FloatArrayType.BYTES_PER_ELEMENT ? FloatArrayType.prototype.BYTES_PER_ELEMENT else bytesPerFloat = 4 module.exports = class ThangState @className: "ThangState" @trackedPropertyTypes: [ "boolean" "number" "string" "array" # will turn everything into strings "object" # grrr "Vector" "Thang" # serialized as ids, like strings ] hasRestored: false constructor: (thang) -> @props = [] # parallel array to @thang's trackedPropertiesKeys/Types return unless thang @thang = thang for prop, propIndex in thang.trackedPropertiesKeys type = thang.trackedPropertiesTypes[propIndex] value = thang[prop] if type is 'Vector' @props.push value?.copy() # could try storing [x, y, z] or {x, y, z} here instead if this is expensive else if type is 'object' @props.push = clone(value, true) else @props.push value # Either pass storage and type, or don't pass either of them getStoredProp: (propIndex, type, storage) -> # Optimize it unless type type = @trackedPropertyTypes[propIndex] storage = @trackedPropertyValues[propIndex] if type is "Vector" value = new Vector storage[3 * @frameIndex], storage[3 * @frameIndex + 1], storage[3 * @frameIndex + 2] else if type is 'string' specialKey = storage[@frameIndex] value = @specialKeysToValues[specialKey] else if type is 'Thang' specialKey = storage[@frameIndex] value = @thang.world.getThangByID @specialKeysToValues[specialKey] else if type is 'array' specialKey = storage[@frameIndex] value = @specialKeysToValues[specialKey] value = value.split('\x1E') # Record Separator else value = storage[@frameIndex] value getStateForProp: (prop) -> # Get the property, whether we have it stored in @props or in @trackedPropertyValues. Optimize it. # Figured based on http://jsperf.com/object-vs-array-vs-native-linked-list/13 that it should be faster with small arrays to do the indexOf reads (each up to 24x faster) than to do a single object read, and then we don't have to maintain an extra @props object; just keep array propIndex = @trackedPropertyKeys.indexOf prop return null if propIndex is -1 value = @props[propIndex] return value if value isnt undefined or @hasRestored return @props[propIndex] = @getStoredProp propIndex restore: -> # Restore trackedProperties' values to @thang, retrieving them from @trackedPropertyValues if needed. Optimize it. return @ if @thang._state is @ unless @hasRestored # Restoring in a deserialized World for first time props = [] for prop, propIndex in @trackedPropertyKeys type = @trackedPropertyTypes[propIndex] storage = @trackedPropertyValues[propIndex] props.push(@thang[prop] = @getStoredProp propIndex, type, storage) #console.log @frameIndex, @thang.id, prop, propIndex, type, storage, "got", @thang[prop] @props = props @trackedPropertyTypes = @trackedPropertyValues = @specialKeysToValues = null # leave @trackedPropertyKeys for indexing @hasRestored = true else # Restoring later times for prop, propIndex in @trackedPropertyKeys @thang[prop] = @props[propIndex] @ serialize: (frameIndex, trackedPropertyIndices, trackedPropertyTypes, trackedPropertyValues, specialValuesToKeys, specialKeysToValues) -> # Performance hotspot--called once per tracked property per Thang per frame. Optimize the crap out of it. for type, newPropIndex in trackedPropertyTypes originalPropIndex = trackedPropertyIndices[newPropIndex] storage = trackedPropertyValues[newPropIndex] value = @props[originalPropIndex] if value # undefined, null, false, 0 won't trigger in this serialization code scheme anyway, so we can't differentiate between them when deserializing if type is "Vector" storage[3 * frameIndex] = value.x storage[3 * frameIndex + 1] = value.y storage[3 * frameIndex + 2] = value.z else if type is 'string' specialKey = specialValuesToKeys[value] unless specialKey specialKey = specialKeysToValues.length specialValuesToKeys[value] = specialKey specialKeysToValues.push value storage[frameIndex] = specialKey storage[frameIndex] = specialKey else if type is 'Thang' value = value.id specialKey = specialValuesToKeys[value] unless specialKey specialKey = specialKeysToValues.length specialValuesToKeys[value] = specialKey specialKeysToValues.push value storage[frameIndex] = specialKey storage[frameIndex] = specialKey else if type is 'array' value = value.join '\x1E' # Record Separator specialKey = specialValuesToKeys[value] unless specialKey specialKey = specialKeysToValues.length specialValuesToKeys[value] = specialKey specialKeysToValues.push value storage[frameIndex] = specialKey storage[frameIndex] = specialKey else storage[frameIndex] = value #console.log @thang.id, "assigned prop", originalPropIndex, newPropIndex, value, type, "at", frameIndex, "to", storage[frameIndex] null @deserialize: (world, frameIndex, thang, trackedPropertyKeys, trackedPropertyTypes, trackedPropertyValues, specialKeysToValues) -> # Optimize like no tomorrow--most performance-sensitive part of the whole app, called once per WorldFrame per Thang per trackedProperty, blocking the UI ts = new ThangState ts.thang = thang ts.frameIndex = frameIndex ts.trackedPropertyKeys = trackedPropertyKeys ts.trackedPropertyTypes = trackedPropertyTypes ts.trackedPropertyValues = trackedPropertyValues ts.specialKeysToValues = specialKeysToValues ts @transferableBytesNeededForType: (type, nFrames) -> bytes = switch type when "boolean" then 1 when "number" then bytesPerFloat when "Vector" then bytesPerFloat * 3 when "string" then 4 when "Thang" then 4 # turn them into strings of their ids when "array" then 4 # turn them into strings and hope it doesn't explode? else 0 # We need to be a multiple of bytesPerFloat otherwise bigger-byte array (Float64Array, etc.) offsets won't work # http://www.kirupa.com/forum/showthread.php?378737-Typed-Arrays-Y-U-No-offset-at-values-other-than-multiples-of-element-size bytesPerFloat * Math.ceil(nFrames * bytes / bytesPerFloat) @createArrayForType: (type, nFrames, buffer, offset) -> bytes = @transferableBytesNeededForType type, nFrames storage = switch type when "boolean" new Uint8Array(buffer, offset, nFrames) when "number" new FloatArrayType(buffer, offset, nFrames) when "Vector" new FloatArrayType(buffer, offset, nFrames * 3) when "string" new Uint32Array(buffer, offset, nFrames) when "Thang" new Uint32Array(buffer, offset, nFrames) when "array" new Uint32Array(buffer, offset, nFrames) else [] [storage, bytes] unless typedArraySupport # Fall back to normal arrays in IE 9 ThangState.createArrayForType = (type, nFrames, buffer, offset) -> bytes = @transferableBytesNeededForType type, nFrames elementsPerFrame = if type is 'Vector' then 3 else 1 storage = (0 for i in [0 ... nFrames * elementsPerFrame]) [storage, bytes]