Block and variable compression. No need to serialize uid of block and shadow if they are the same, reduce duplication of information.

This commit is contained in:
Karishma Chadha 2018-03-27 13:00:58 -04:00
parent 4b62a938c4
commit 334058b081
2 changed files with 204 additions and 16 deletions

View file

@ -8,6 +8,7 @@ const vmPackage = require('../../package.json');
const Blocks = require('../engine/blocks');
const Sprite = require('../sprites/sprite');
const Variable = require('../engine/variable');
const log = require('../util/log');
const {loadCostume} = require('../import/load-costume.js');
const {loadSound} = require('../import/load-sound.js');
@ -25,16 +26,63 @@ const {deserializeCostume, deserializeSound} = require('./deserialize-assets.js'
* @property {Map.<string, string>} extensionURLs - map of ID => URL from project metadata. May not match extensionIDs.
*/
const INPUT_SAME_BLOCK_SHADOW = 1;
const INPUT_BLOCK_NO_SHADOW = 2;
const INPUT_DIFF_BLOCK_SHADOW = 3;
// haven't found a case where block = null, but shadow is present...
const serializeInputs = function (inputs) {
const obj = Object.create(null);
for (const inputName in inputs) {
if (!inputs.hasOwnProperty(inputName)) continue;
// if block and shadow refer to the same block, only serialize one
if (inputs[inputName].block === inputs[inputName].shadow) {
// has block and shadow, and they are the same
obj[inputName] = [
INPUT_SAME_BLOCK_SHADOW,
inputs[inputName].block
];
} else if (inputs[inputName].shadow === null) {
// does not have shadow
obj[inputName] = [
INPUT_BLOCK_NO_SHADOW,
inputs[inputName].block
];
} else {
// block and shadow are both present and are different
obj[inputName] = [
INPUT_DIFF_BLOCK_SHADOW,
inputs[inputName].block,
inputs[inputName].shadow
];
}
}
return obj;
};
const serializeFields = function (fields) {
const obj = Object.create(null);
for (const fieldName in fields) {
if (!fields.hasOwnProperty(fieldName)) continue;
obj[fieldName] = [fields[fieldName].value];
if (fields[fieldName].hasOwnProperty('id')) {
obj[fieldName].push(fields[fieldName].id);
}
}
return obj;
};
const serializeBlock = function (block) {
const obj = Object.create(null);
obj.id = block.id;
// obj.id = block.id; // don't need this, it's the index of this block in its containing object
obj.opcode = block.opcode;
obj.next = block.next;
if (block.next) obj.next = block.next; // don't serialize next if null
// obj.next = if (block.next;
obj.parent = block.parent;
obj.inputs = block.inputs;
obj.fields = block.fields;
obj.inputs = serializeInputs(block.inputs);
obj.fields = serializeFields(block.fields);
obj.topLevel = block.topLevel ? block.topLevel : false;
obj.shadow = block.shadow;
obj.shadow = block.shadow; // I think we don't need this either..
if (block.topLevel) {
if (block.x) {
obj.x = Math.round(block.x);
@ -92,11 +140,48 @@ const serializeSound = function (sound) {
return obj;
};
const serializeVariables = function (variables) {
const obj = Object.create(null);
// separate out variables into types at the top level so we don't have
// keep track of a type for each
obj.variables = Object.create(null);
obj.lists = Object.create(null);
obj.broadcasts = Object.create(null);
for (const varId in variables) {
const v = variables[varId];
if (v.type === Variable.BROADCAST_MESSAGE_TYPE) {
obj.broadcasts[varId] = [v.name, v.value];
continue;
}
if (v.type === Variable.LIST_TYPE) {
obj.lists[varId] = [v.name, v.value];
continue;
}
// should be a scalar type
obj.variables[varId] = [v.name]
let val = v.value;
if ((typeof val !== 'string') && (typeof val !== 'number')) {
log.info(`Variable: ${v.name} had value ${val} of type: ${typeof val} converting to string`);
val = JSON.stringify(val);
}
obj.variables[varId].push(val);
// Some hacked blocks have booleans as variable values
// (typeof v.value === 'string') || (typeof v.value === 'number') ?
// v.value : JSON.stringify(v.value)];
if (v.isPersistent) obj.variables[varId].push(true);
}
return obj;
};
const serializeTarget = function (target) {
const obj = Object.create(null);
obj.isStage = target.isStage;
obj.name = target.name;
obj.variables = target.variables; // This means that uids for variables will persist across saves/loads
const vars = serializeVariables(target.variables);
obj.variables = vars.variables;
obj.lists = vars.lists;
obj.broadcasts = vars.broadcasts;
obj.blocks = serializeBlocks(target.blocks);
obj.currentCostume = target.currentCostume;
obj.costumes = target.costumes.map(serializeCostume);
@ -142,6 +227,59 @@ const serialize = function (runtime) {
return obj;
};
const deserializeInputs = function (inputs) {
// Explicitly not using Object.create(null) here
// because we call prototype functions later in the vm
const obj = {};
for (const inputName in inputs) {
if (!inputs.hasOwnProperty(inputName)) continue;
const inputDescArr = inputs[inputName];
let block = null;
let shadow = null;
const blockShadowInfo = inputDescArr[0];
if (blockShadowInfo === INPUT_SAME_BLOCK_SHADOW) {
// block and shadow are the same id, and only one is provided
block = shadow = inputDescArr[1];
} else if (blockShadowInfo === INPUT_BLOCK_NO_SHADOW) {
block = inputDescArr[1];
} else { // assume INPUT_DIFF_BLOCK_SHADOW
block = inputDescArr[1];
shadow = inputDescArr[2];
}
obj[inputName] = {
name: inputName,
block: block,
shadow: shadow
};
}
return obj;
};
const deserializeFields = function (fields) {
// Explicitly not using Object.create(null) here
// because we call prototype functions later in the vm
const obj = {};
for (const fieldName in fields) {
if (!fields.hasOwnProperty(fieldName)) continue;
const fieldDescArr = fields[fieldName];
obj[fieldName] = {
name: fieldName,
value: fieldDescArr[0]
};
if (fieldDescArr.length > 1) {
obj[fieldName].id = fieldDescArr[1];
}
if (fieldName === 'BROADCAST_OPTION') {
obj[fieldName].variableType = Variable.BROADCAST_MESSAGE_TYPE;
} else if (fieldName === 'VARIABLE') {
obj[fieldName].variableType = Variable.SCALAR_TYPE;
} else if (fieldName === 'LIST') {
obj[fieldName].variableType = Variable.LIST_TYPE;
}
}
return obj;
};
/**
* Parse a single "Scratch object" and create all its in-memory VM objects.
* @param {!object} object From-JSON "Scratch object:" sprite, stage, watcher.
@ -170,6 +308,13 @@ const parseScratchObject = function (object, runtime, extensions, zip) {
for (const blockId in object.blocks) {
if (!object.blocks.hasOwnProperty(blockId)) continue;
const blockJSON = object.blocks[blockId];
blockJSON.id = blockId; // add id back to block since it wasn't serialized
const serializedInputs = blockJSON.inputs;
const deserializedInputs = deserializeInputs(serializedInputs);
blockJSON.inputs = deserializedInputs;
const serializedFields = blockJSON.fields;
const deserializedFields = deserializeFields(serializedFields);
blockJSON.fields = deserializedFields;
blocks.createBlock(blockJSON);
const dotIndex = blockJSON.opcode.indexOf('.');
@ -238,18 +383,55 @@ const parseScratchObject = function (object, runtime, extensions, zip) {
const target = sprite.createClone();
// Load target properties from JSON.
if (object.hasOwnProperty('variables')) {
for (const j in object.variables) {
const variable = object.variables[j];
const newVariable = new Variable(
variable.id,
variable.name,
variable.type,
variable.isPersistent
);
newVariable.value = variable.value;
for (const varId in object.variables) {
const variable = object.variables[varId];
let newVariable;
if (Array.isArray(variable)) {
newVariable = new Variable(
varId, // var id is the index of the variable desc array in the variables obj
variable[0], // name of the variable
Variable.SCALAR_TYPE, // type of the variable
(variable.length === 3) ? variable[2] : false // isPersistent/isCloud
);
newVariable.value = variable[1];
} else {
newVariable = new Variable(
variable.id,
variable.name,
variable.type,
variable.isPersistent
);
newVariable.value = variable.value;
}
target.variables[newVariable.id] = newVariable;
}
}
if (object.hasOwnProperty('lists')) {
for (const listId in object.lists) {
const list = object.lists[listId];
const newList = new Variable(
listId,
list[0],
Variable.LIST_TYPE,
false
);
newList.value = list[1];
target.variables[newList.id] = newList;
}
}
if (object.hasOwnProperty('broadcasts')) {
for (const broadcastId in object.broadcasts) {
const broadcast = object.broadcasts[broadcastId];
const newBroadcast = new Variable(
broadcastId,
broadcast[0],
Variable.BROADCAST_MESSAGE_TYPE,
false
);
newBroadcast.value = broadcast[1];
target.variables[newBroadcast.id] = newBroadcast;
}
}
if (object.hasOwnProperty('x')) {
target.x = object.x;
}

View file

@ -256,7 +256,13 @@ class VirtualMachine extends EventEmitter {
zip.file(currCostume.fileName, currCostume.fileContent);
}
return zip.generateAsync({type: 'blob'});
return zip.generateAsync({
type: 'blob',
compression: 'DEFLATE',
compressionOptions: {
level: 9 // best compression (level 1 would be best speed)
}
});
}
/**