ianmackenzie/elm-geometry

Add BoundingBox2d.aspectRatio

Open

#133 opened on May 30, 2020

View on GitHubContributor guide
 (1 comment) (0 reactions) (0 assignees)Elm (28 forks)auto 404
Hacktoberfest

Repository metrics

Stars
 (186 stars)
PR merge metrics
 (PR metrics pending)

Description

I've found that I've needed this function a couple times. Writing the code in a one-off fashion looks like this

( w, h ) =
    BoundingBox2d.dimensions boundingBox

aspectRatio =
    Quantity.ratio h w

safeAspectRatio = 
    if isNaN aspectRatio || isInfinite aspectRatio then
        Nothing
    else
        Just aspectRatio

This is verbose so it would be nice to just have as BoundingBox2d.aspectRatio: BoundingBox2d -> Maybe Float and possibly BoundingBox2d.aspectRatioInv: BoundingBox2d -> Maybe Float for the width over height version.

Edit: I know elm-geometry tends to avoid having functions that depend on a particular x y coordinate system but I think an exception should be made for BoundingBox2d since it's already defined in terms of an x y coordinate system.

Contributor guide

Research direction
Implement the aspectRatio function by extracting dimensions from a BoundingBox2d, computing the ratio of height to width, handling division by zero and NaN cases, and returning Maybe Float.
Tech stack
None
Domain
computer graphics
Issue type
Feature
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
ElmGit
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
75