whatwg/html

Small clarity improvements to canvas transform methods

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#2,848 建立於 2017年7月19日

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 (7 留言) (1 反應) (0 負責人)HTML (7,654 star) (2,520 fork)batch import
clarificationgood first issuetopic: canvas

描述

While in the area for #2845, I noticed the following small tweaks that we could make to improve that section of the spec:

  • Replace "abort these steps" with "return" everywhere. (The latter is a more modern convention, per Infra.)
  • Link "multiplying" in the definition of transform(a, b, c, d, e, f) to https://drafts.fxtf.org/geometry/#matrix-multiply
  • Re-do setTransform(a, b, c, d, e, f) steps 2-3 to reset the current transformation matrix to the appropriate matrix (a c e / b d f / 0 0 1), instead of resetting the matrix to the identity matrix then invoking the transform() method. It's bad practice to invoke methods from other methods.

This is a good first bug :)

貢獻者指南

技術棧
htmlcssjavascript
領域
documentation
議題類型
documentation
難度面向新貢獻者的預計實作難度，1 表示很小改動，5 表示專家級工作。
2
預計時間有經驗貢獻者完成調查、實作、測試並準備 pull request 的粗略時間範圍。
1-3 hours
活動狀態議題目前的可參與程度：新鮮、活躍、陳舊、阻塞或等待維護者輸入。
stale
清晰度議題是否清楚說明預期改動、驗收標準和下一步。
clear
前置要求
understanding of HTML specification stylebasic knowledge of canvas transformations
新手友善度1-100 的估計分數，表示該議題對首次貢獻者的友善程度。
80
研究方向
The issue requests three small changes to the canvas transformations section of the HTML spec (https://html.spec.whatwg.org/#transformations). First, replace 'abort these steps' with 'return' throughout, following the Infra spec convention (https://infra.spec.whatwg.org/). Second, add a link to 'multiplying' in the definition of transform(a, b, c, d, e, f) pointing to https://drafts.fxtf.org/geometry/#matrix multiply. Third, rewrite setTransform(a, b, c, d, e, f) steps 2-3 to directly reset the transformation matrix instead of invoking transform(). Check the spec source (likely in the whatwg/html repository) to locate the relevant text and make these edits. The issue has some strike throughs indicating partial completion, so verify which items remain.