Infinite loop when drawing large ligatures to char atlas · xtermjs/xterm.js#4362

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area/addon/ligaturesarea/addon/webglhelp wantedtype/bug

説明

some fonts provide extremely long ligatures, e.g. Fira Code for =================================================== The char atlas code tries to find a row to fit it but fails and gets stuck in an infinite loop https://github.com/xtermjs/xterm.js/blob/fe8981766769c19ab1903dffa19f1a64ad83da13/src/browser/renderer/shared/TextureAtlas.ts#L792-L799 ^Here we're checking if there's room on the current row and creating a new one if not.

Install Fira Code font, Run the xterm demo and enable ligatures
start typing =
Keep looking at the char atlas drawn below, once the glyph is almost the same width as char atlas, typing the next = will freeze everything.

技術スタック: typescript
領域: frontend
Issue 種別: bug
難度: 3
推定時間: 1-3 hours
活動状況: stale
明確さ: clear
前提条件: TypeScriptCanvas renderingTexture atlas concept
初心者向け度: 60
調査方針: Investigate the function at src/browser/renderer/shared/TextureAtlas.ts lines 792-799. The loop currently creates a new row but does not handle the case where the glyph width exceeds the atlas width, leading to an infinite loop. Consider adding a maximum row attempt check or ensuring that if a new row is still too small, the glyph is skipped or an error is thrown. Review the Canvas rendering logic to understand row dimensions.