[Bug]: Incorrect calculation in Typography Tokens

[Tayebsed93]

Prerequisites

• I have searched the backlog for duplicate or closed feature requests

Your test device

Iphone 14 Pro Max

OS Version

iOS 18

App version

v0.5.0

Describe the issue

There is an issue in the Design System where the lineHeight is incorrectly calculated for typography tokens.

The current formula used is:

lineHeight = Line / Size
Example: 48 / 40 = 1.2

This leads to inaccurate values across all typography tokens.

Documentation Flutter : https://api.flutter.dev/flutter/painting/TextStyle/height.html

Expected Behavior

The correct formula should be:

lineHeight = Size / Line
Example: 40 / 48 = 0.833

Example:

For the DisplayLarge token:

• Font Size: 40px
• Line Height: 48px

✅ Expected lineHeight value:

[Tayebsed93]

📣 New Firebase App Distribution ALPHA upload available 🚀 (Android)

Please, get the new build from App Tester app, or contact the project maintainers (@Tayebsed93) to get access.

Display name: DesignToolbox (alpha) (311)
Version: 0.5.0
Build type: ALPHA
Build details (GitHub): 272
cc @B3nz01d (product owner)
cc @Tayebsed93 @AhmedAmineZr @nouha06 (dev team)
cc @MaximeTonnerre @jerome-regnier (design team)

[Tayebsed93]

📣 New TestFlight ALPHA upload available 🚀 (iOS)

Please, get the new build from TestFlight app, or contact the project maintainers (@Tayebsed93) to get access.

Display name: Design Toolbox Flutter (311)
Version: 0.5.0
Build type: ALPHA
Build details (GitHub): 272
cc @B3nz01d (product owner)
cc @Tayebsed93 @AhmedAmineZr @nouha06 (dev team)
cc @MaximeTonnerre @jerome-regnier (design team)

[jerome-regnier]

@Tayebsed93 , Je viens de charger la version 0.5.0 Alpha sur Android. Impossible sur iOS qui rencontre un problème de téléchargement du package.
Toutefois, je te confirme que les textes sont bien trop proches voir, ils se chevauchent.
Je pense que ton calcul était le bon et que le ratio est inversé dans la documentation.

[Tayebsed93]

@jerome-regnier j'ai remis les valeurs comme avant.
Les textes sont affichés sur 2,3 lignes pour tes tests