Merge pull request #59 from jwetzell/speed-up

Performance enhancements

src/decoders/chunk.ts

@@ -1,16 +1,16 @@
 import { Chunk } from '../models/chunk';
 
 export default (buffer: Uint8Array): Chunk => {
-  let offset = 0;
-  const view = new DataView(buffer.buffer, buffer.byteOffset, buffer.byteLength);
-  const id = view.getUint16(offset, true);
-  offset += 2;
+  if (buffer.length < 4) {
+    throw new Error('Chunk buffer must be at least 4 bytes');
+  }
+
+  const id = (buffer[1] << 8) + buffer[0];
 
   // NOTE(jwetzell): this data is split up as 1 bit for hasSubchunks and 15 bits for the dataLen
-  const combinedLengthAndFlag = view.getUint16(offset, true);
+  const combinedLengthAndFlag = (buffer[3] << 8) + buffer[2];
   const hasSubchunks = combinedLengthAndFlag > 32768;
   const dataLen = hasSubchunks ? combinedLengthAndFlag - 32768 : combinedLengthAndFlag;
-  offset += 2;
 
   const header = {
     id,
@@ -18,7 +18,7 @@ export default (buffer: Uint8Array): Chunk => {
     hasSubchunks,
   };
 
-  const chunkData = buffer.subarray(offset, offset + header.dataLen);
+  const chunkData = buffer.subarray(4, 4 + header.dataLen);
 
   const chunk = {
     chunkData,

src/decoders/data/data-packet-chunk.ts

@@ -10,8 +10,7 @@ export default (buffer: Uint8Array): DataPacketChunk => {
   if (chunk.header.hasSubchunks && chunk.chunkData && chunk.header.dataLen) {
     let offset = 0;
     while (offset < chunk.header.dataLen) {
-      const view = new DataView(chunk.chunkData.buffer, chunk.chunkData.byteOffset, chunk.chunkData.byteLength);
-      const chunkId = view.getUint16(offset, true);
+      const chunkId = (chunk.chunkData.subarray(offset)[1] << 8) + chunk.chunkData.subarray(offset)[0];
       switch (chunkId) {
         case 0x0000:
           data.packetHeader = Decoders.PacketHeaderChunk(chunk.chunkData.subarray(offset));

src/decoders/info/info-packet-chunk.ts

@@ -10,8 +10,7 @@ export default (buffer: Uint8Array): InfoPacketChunk => {
   if (chunk.header.hasSubchunks && chunk.chunkData && chunk.header.dataLen) {
     let offset = 0;
     while (offset < chunk.header.dataLen) {
-      const view = new DataView(chunk.chunkData.buffer, chunk.chunkData.byteOffset, chunk.chunkData.byteLength);
-      const chunkId = view.getUint16(offset, true);
+      const chunkId = (chunk.chunkData.subarray(offset)[1] << 8) + chunk.chunkData.subarray(offset)[0];
       switch (chunkId) {
         case 0x0000:
           data.packetHeader = Decoders.PacketHeaderChunk(chunk.chunkData.subarray(offset));

src/decoders/info/info-system-name-chunk.ts

@@ -1,11 +1,12 @@
 import { Decoders } from '..';
 import { InfoSystemNameChunk, InfoSystemNameChunkData } from '../../models/info/info-system-name-chunk';
 
+const nameDecoder = new TextDecoder();
 export default (buffer: Uint8Array): InfoSystemNameChunk => {
   const chunk = Decoders.Chunk(buffer);
 
   const data: InfoSystemNameChunkData = {
-    systemName: new TextDecoder().decode(chunk.chunkData.subarray(0, chunk.header.dataLen)),
+    systemName: nameDecoder.decode(chunk.chunkData.subarray(0, chunk.header.dataLen)),
   };
 
   return {

src/decoders/info/info-tracker-chunk.ts

@@ -8,8 +8,7 @@ export default (buffer: Uint8Array): InfoTrackerChunk => {
   if (chunk.header.hasSubchunks && chunk.chunkData && chunk.header.dataLen) {
     let offset = 0;
     while (offset < chunk.header.dataLen) {
-      const view = new DataView(chunk.chunkData.buffer, chunk.chunkData.byteOffset, chunk.chunkData.byteLength);
-      const chunkId = view.getUint16(offset, true);
+      const chunkId = (chunk.chunkData.subarray(offset)[1] << 8) + chunk.chunkData.subarray(offset)[0];
       switch (chunkId) {
         case 0x0000: {
           const data: InfoTrackerChunkData = {

src/decoders/info/info-tracker-name-chunk.ts

@@ -1,11 +1,12 @@
 import { Decoders } from '..';
 import { InfoTrackerNameChunk, InfoTrackerNameChunkData } from '../../models/info/info-tracker-name-chunk';
 
+const nameDecoder = new TextDecoder();
 export default (buffer: Uint8Array): InfoTrackerNameChunk => {
   const chunk = Decoders.Chunk(buffer);
 
   const data: InfoTrackerNameChunkData = {
-    trackerName: new TextDecoder().decode(chunk.chunkData.subarray(0, chunk.header.dataLen)),
+    trackerName: nameDecoder.decode(chunk.chunkData.subarray(0, chunk.header.dataLen)),
   };
 
   return {

src/decoders/packet-header-chunk.ts

@@ -4,9 +4,16 @@ import { PacketHeaderChunk, PacketHeaderChunkData } from '../models/packet-heade
 export default (buffer: Uint8Array): PacketHeaderChunk => {
   const chunk = Decoders.Chunk(buffer);
 
-  const view = new DataView(chunk.chunkData.buffer, chunk.chunkData.byteOffset, chunk.chunkData.byteLength);
+  let packetTimestamp = BigInt(chunk.chunkData[7]) << BigInt(56);
+  packetTimestamp += BigInt(chunk.chunkData[6]) << BigInt(48);
+  packetTimestamp += BigInt(chunk.chunkData[5]) << BigInt(40);
+  packetTimestamp += BigInt(chunk.chunkData[4]) << BigInt(32);
+  packetTimestamp += BigInt(chunk.chunkData[3]) << BigInt(24);
+  packetTimestamp += BigInt(chunk.chunkData[2]) << BigInt(16);
+  packetTimestamp += BigInt(chunk.chunkData[1]) << BigInt(8);
+  packetTimestamp += BigInt(chunk.chunkData[0]);
   const data: PacketHeaderChunkData = {
-    packetTimestamp: view.getBigUint64(0, true),
+    packetTimestamp,
     versionHigh: chunk.chunkData[8],
     versionLow: chunk.chunkData[9],
     frameId: chunk.chunkData[10],

src/encoders/chunk.ts

@@ -1,3 +1,4 @@
+const header = new DataView(new ArrayBuffer(4));
 export default (id: number, chunkData: Uint8Array, hasSubchunks: boolean): Uint8Array => {
   if (!Number.isInteger(id)) {
     throw new Error('chunk id must be an integer');
@@ -11,7 +12,6 @@ export default (id: number, chunkData: Uint8Array, hasSubchunks: boolean): Uint8
     throw new Error('chunkData can not be greater than 32767 bytes');
   }
 
-  const header = new DataView(new ArrayBuffer(4));
   header.setUint16(0, id, true);
   const hasSubChunksBit = (hasSubchunks ? 1 : 0) << 15;
   header.setUint16(2, hasSubChunksBit + chunkData.length, true);

src/encoders/data/data-tracker-accel-chunk.ts

@@ -1,9 +1,9 @@
 import chunk from '../chunk';
 
+const floatArray = new Float32Array(3);
 export default (x: number, y: number, z: number): Uint8Array => {
-  const buf = new DataView(new ArrayBuffer(12));
-  buf.setFloat32(0, x, true);
-  buf.setFloat32(4, y, true);
-  buf.setFloat32(8, z, true);
-  return chunk(0x0004, new Uint8Array(buf.buffer), false);
+  floatArray[0] = x;
+  floatArray[1] = y;
+  floatArray[2] = z;
+  return chunk(0x0004, new Uint8Array(floatArray.buffer), false);
 };

src/encoders/data/data-tracker-ori-chunk.ts

@@ -1,10 +1,9 @@
 import chunk from '../chunk';
 
+const floatArray = new Float32Array(3);
 export default (x: number, y: number, z: number): Uint8Array => {
-  const buf = new DataView(new ArrayBuffer(12));
-
-  buf.setFloat32(0, x, true);
-  buf.setFloat32(4, y, true);
-  buf.setFloat32(8, z, true);
-  return chunk(0x0002, new Uint8Array(buf.buffer), false);
+  floatArray[0] = x;
+  floatArray[1] = y;
+  floatArray[2] = z;
+  return chunk(0x0002, new Uint8Array(floatArray.buffer), false);
 };

src/encoders/data/data-tracker-pos-chunk.ts

@@ -1,11 +1,10 @@
 import chunk from '../chunk';
 
+const floatArray = new Float32Array(3);
 export default (x: number, y: number, z: number): Uint8Array => {
-  const buf = new DataView(new ArrayBuffer(12));
+  floatArray[0] = x;
+  floatArray[1] = y;
+  floatArray[2] = z;
 
-  buf.setFloat32(0, x, true);
-  buf.setFloat32(4, y, true);
-  buf.setFloat32(8, z, true);
-
-  return chunk(0x0000, new Uint8Array(buf.buffer), false);
+  return chunk(0x0000, new Uint8Array(floatArray.buffer), false);
 };

src/encoders/data/data-tracker-speed-chunk.ts

@@ -1,11 +1,10 @@
 import chunk from '../chunk';
 
+const floatArray = new Float32Array(3);
 export default (x: number, y: number, z: number): Uint8Array => {
-  const buf = new DataView(new ArrayBuffer(12));
+  floatArray[0] = x;
+  floatArray[1] = y;
+  floatArray[2] = z;
 
-  buf.setFloat32(0, x, true);
-  buf.setFloat32(4, y, true);
-  buf.setFloat32(8, z, true);
-
-  return chunk(0x0001, new Uint8Array(buf.buffer), false);
+  return chunk(0x0001, new Uint8Array(floatArray.buffer), false);
 };

src/encoders/data/data-tracker-status-chunk.ts

@@ -1,7 +1,7 @@
 import chunk from '../chunk';
 
+const floatArray = new Float32Array(1);
 export default (validity: number): Uint8Array => {
-  const buf = new DataView(new ArrayBuffer(4));
-  buf.setFloat32(0, validity, true);
-  return chunk(0x0003, new Uint8Array(buf.buffer), false);
+  floatArray[0] = validity;
+  return chunk(0x0003, new Uint8Array(floatArray.buffer), false);
 };

src/encoders/data/data-tracker-timestamp-chunk.ts

@@ -1,7 +1,7 @@
 import chunk from '../chunk';
 
+const buf = new DataView(new ArrayBuffer(8));
 export default (timestamp: bigint): Uint8Array => {
-  const buf = new DataView(new ArrayBuffer(8));
   buf.setBigUint64(0, BigInt(timestamp), true);
   return chunk(0x0006, new Uint8Array(buf.buffer), false);
 };

src/encoders/data/data-tracker-trgtpos-chunk.ts

@@ -1,11 +1,10 @@
 import chunk from '../chunk';
 
+const floatArray = new Float32Array(3);
 export default (x: number, y: number, z: number): Uint8Array => {
-  const buf = new DataView(new ArrayBuffer(12));
+  floatArray[0] = x;
+  floatArray[1] = y;
+  floatArray[2] = z;
 
-  buf.setFloat32(0, x, true);
-  buf.setFloat32(4, y, true);
-  buf.setFloat32(8, z, true);
-
-  return chunk(0x0005, new Uint8Array(buf.buffer), false);
+  return chunk(0x0005, new Uint8Array(floatArray.buffer), false);
 };

src/encoders/info/info-system-name-chunk.ts

@@ -1,3 +1,3 @@
 import chunk from '../chunk';
-
-export default (systemName: string): Uint8Array => chunk(0x0001, new TextEncoder().encode(systemName), false);
+const nameEncoder = new TextEncoder();
+export default (systemName: string): Uint8Array => chunk(0x0001, nameEncoder.encode(systemName), false);

src/encoders/info/info-tracker-name-chunk.ts

@@ -1,3 +1,4 @@
 import chunk from '../chunk';
 
-export default (trackerName: string) => chunk(0x0000, new TextEncoder().encode(trackerName), false);
+const nameEncoder = new TextEncoder();
+export default (trackerName: string) => chunk(0x0000, nameEncoder.encode(trackerName), false);

src/encoders/packet-header-chunk.ts

@@ -1,5 +1,6 @@
 import chunk from './chunk';
 
+const packetHeader = new DataView(new ArrayBuffer(12));
 export default (
   timestamp: bigint,
   versionHigh: number,
@@ -33,7 +34,6 @@ export default (
     throw new Error('frame packet count must be >= 0 and <= 255');
   }
 
-  const packetHeader = new DataView(new ArrayBuffer(12));
   packetHeader.setBigUint64(0, BigInt(timestamp), true);
   packetHeader.setUint8(8, versionHigh);
   packetHeader.setUint8(9, versionLow);