3D transparency proposal

オープン
  • 何か問題がありますか？
#8,112 コメント 1 件 リアクション 0 件 担当者 0 名 GitHub で見る

メンテナーはふだん 2 日以内に返信

まだ誰も着手していません。

評価

難易度
5/5
見積もり時間
1週間以上
初心者へのやさしさ
8/100
issue の種類
機能追加
明瞭さ
おおむね明確
活発さ
活発
技術スタック
javascript
領域
data-visualization

調査の方向性

This is a design proposal for screen-space blue-noise transparency in plotly.js's 3D surfaces, and the payload names no files, tests or entry points. Start by reading the linked issues (#1267, #3243, #4918) to see what has already been tried. Done would mean a maintainer-agreed design and a prototype, so a first-time contributor should discuss the approach in the thread before writing code.

索引モデルが issue の本文から書いたものです。

説明

enhancement feature P3 plotly-internal size: 5

3D transparency has always been tricky, and has never worked very well in plotly.js. - see eg https://github.com/plotly/plotly.js/issues/1267 https://github.com/plotly/plotly.js/issues/3243 https://github.com/plotly/plotly.js/issues/4918 for just a few examples. Several years ago I played with an approach that seemed promising - treating opacity as a semi-random probability of drawing or not drawing a pixel, then oversampling / averaging to smooth the result. I never got it working well enough to include in the library, but in another project (not using plotly.js) a colleague of mine has refined the concept into what I think is a really beautiful, performant, and useful result so I'm sharing here in case someone wants to bring it into plotly.js

  • Each transparent surface gets a repeatable, screen-space random blue noise function that yields values between 0 and 1. This means if you pass through multiple layers of the same surface we will not make it as opaque as it really should be (because they all use the same screen-space function), but because of the next point, the result still looks physically reasonable, and arguably more useful than the full opacity of a complete physical model. If you don't use screen space for the noise function (use full 3D space for example) then there's a distracting amount of motion to the noise as you move the viewport.
  • The transparency at each pixel becomes T^(1/cos(theta)) where T is the given transparency and theta is the angle at that pixel between the surface normal and the camera. This makes shallow-incidence areas more opaque, modeling a physical system where you're passing through a greater thickness of the material depending on this angle.
  • Only pixels where the final opacity is greater than the blue noise function (and where we haven't already drawn a surface closer to the camera) are drawn. All the same lighting effects used for opaque surfaces can still be used.
  • During mouse interactions this is what we display, so it looks grainy but you still see the features and on average they are correct. This is one area I still think the algorithm we're using could be improved, it often looks kind of like those old "Magic Eye" books whereas I think with some experimentation we could get it a bit flatter, but it's entirely usable in this form.
  • Once the mouse stops moving we average many frames (in the video below we use 64 frames) of this with different random seeds on the blue noise functions, to smooth away the graininess. In the averaging process it's important to distinguish between sRGB and linear color.

https://github.com/user-attachments/assets/29266885-2745-4077-a7db-33d24d96daee

主要言語
JavaScript
スター
18.4k
フォーク
2.1k
平均マージ
1日 5時間
マージ済み PR（30日）
12

環境構築

はじめの一歩

  1. issue を最後まで読み、次にプロジェクトのコントリビューションガイドを読みます。
  2. 着手することを issue にコメントします — 二人が同じ作業をするのを防げます。
  3. リポジトリをフォークし、ブランチを切って変更します。
  4. issue 番号を参照したプルリクエストを送ります。

plotly/plotly.js のほかの issue

plotly/plotly.js の issue をすべて見る

似ている issue

JavaScript の issue をもっと見る

新しい issue をメールで受け取る

初心者向けの GitHub issue を短くまとめたダイジェスト。