diff options
Diffstat (limited to 'node_modules/xterm/src/browser/renderer/atlas/CharAtlasCache.ts')
-rw-r--r-- | node_modules/xterm/src/browser/renderer/atlas/CharAtlasCache.ts | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/node_modules/xterm/src/browser/renderer/atlas/CharAtlasCache.ts b/node_modules/xterm/src/browser/renderer/atlas/CharAtlasCache.ts new file mode 100644 index 0000000..257835b --- /dev/null +++ b/node_modules/xterm/src/browser/renderer/atlas/CharAtlasCache.ts @@ -0,0 +1,95 @@ +/** + * Copyright (c) 2017 The xterm.js authors. All rights reserved. + * @license MIT + */ + +import { generateConfig, configEquals } from 'browser/renderer/atlas/CharAtlasUtils'; +import { BaseCharAtlas } from 'browser/renderer/atlas/BaseCharAtlas'; +import { DynamicCharAtlas } from 'browser/renderer/atlas/DynamicCharAtlas'; +import { ICharAtlasConfig } from 'browser/renderer/atlas/Types'; +import { IColorSet } from 'browser/Types'; +import { ITerminalOptions } from 'common/services/Services'; + +interface ICharAtlasCacheEntry { + atlas: BaseCharAtlas; + config: ICharAtlasConfig; + // N.B. This implementation potentially holds onto copies of the terminal forever, so + // this may cause memory leaks. + ownedBy: number[]; +} + +const charAtlasCache: ICharAtlasCacheEntry[] = []; + +/** + * Acquires a char atlas, either generating a new one or returning an existing + * one that is in use by another terminal. + */ +export function acquireCharAtlas( + options: ITerminalOptions, + rendererId: number, + colors: IColorSet, + scaledCharWidth: number, + scaledCharHeight: number +): BaseCharAtlas { + const newConfig = generateConfig(scaledCharWidth, scaledCharHeight, options, colors); + + // Check to see if the renderer already owns this config + for (let i = 0; i < charAtlasCache.length; i++) { + const entry = charAtlasCache[i]; + const ownedByIndex = entry.ownedBy.indexOf(rendererId); + if (ownedByIndex >= 0) { + if (configEquals(entry.config, newConfig)) { + return entry.atlas; + } + // The configs differ, release the renderer from the entry + if (entry.ownedBy.length === 1) { + entry.atlas.dispose(); + charAtlasCache.splice(i, 1); + } else { + entry.ownedBy.splice(ownedByIndex, 1); + } + break; + } + } + + // Try match a char atlas from the cache + for (let i = 0; i < charAtlasCache.length; i++) { + const entry = charAtlasCache[i]; + if (configEquals(entry.config, newConfig)) { + // Add the renderer to the cache entry and return + entry.ownedBy.push(rendererId); + return entry.atlas; + } + } + + const newEntry: ICharAtlasCacheEntry = { + atlas: new DynamicCharAtlas( + document, + newConfig + ), + config: newConfig, + ownedBy: [rendererId] + }; + charAtlasCache.push(newEntry); + return newEntry.atlas; +} + +/** + * Removes a terminal reference from the cache, allowing its memory to be freed. + */ +export function removeTerminalFromCache(rendererId: number): void { + for (let i = 0; i < charAtlasCache.length; i++) { + const index = charAtlasCache[i].ownedBy.indexOf(rendererId); + if (index !== -1) { + if (charAtlasCache[i].ownedBy.length === 1) { + // Remove the cache entry if it's the only renderer + charAtlasCache[i].atlas.dispose(); + charAtlasCache.splice(i, 1); + } else { + // Remove the reference from the cache entry + charAtlasCache[i].ownedBy.splice(index, 1); + } + break; + } + } +} |