[Feature request] Add advanced arrow configuration (independent head size, fixed stroke width, double-headed arrows)

[alialim]

Platforms

iOS

Description

Hi Alex,

thanks again for your great work on Pro Image Editor!
While working with arrows/lines App and Web, we’ve run into a few concrete needs that would help a lot for our use cases (site plans):

1. Arrowhead size independent from stroke width

Issue: With very thin strokes, the arrowhead looks too large in proportion.
Request: Make the arrowhead’s size/geometry decoupled from lineWidth and configurable—ideally via config.

Goal: subtle, smaller black arrows — constant stroke width with a smaller/thinner head.

2. Change length without scaling thickness (all line types)

Issue: When resizing, the entire element scales, making it look thicker.
Request: Allow dragging the endpoints so only the length changes while stroke width stays constant (pixel-based).
Should apply to all line types (solid, dashed, dash-dot, arrow).

3. Optional arrowheads on both ends

Request: Option for double-headed arrows (head at start and end) using the small head dimensions above.
Example:

arrowHead: ArrowHeadConfigs(
doubleHeaded: true,
)

Happy to share:

a short recording of the save flow (with timing), and

screenshots/examples (current vs desired) for the arrows.

Thanks in advance for your thoughts—and again, big kudos for the editor!

Best regards,
Ali

Why

We use Pro Image Editor primarily for site-plan annotations in civil engineering/construction. Our teams regularly mark up trench routes, utilities, traffic management layouts, and as-built updates on PDF/PNG plans—often in the field and on older devices—so clear, consistent plan edits are critical for daily operations and documentation.

[hm21]

Hey Ali,

Yes, that's definitely a useful use case. My current plan is to search for a way to allow users to create their own path builder to create any shape they like. For example, they could add arrows on two sides and change how the arrows look, etc.

However, implementing that feature will take some time, so if you need it quickly, i recommend that you add it directly to the editor. You can follow the guide I gave to another dev last time here. It's simple, but it will require some time to implement. Currently i'm very busy, but I should have time for a quick review/merge/publish.
But don't worry, as I said, my plan is to add an option for users to define these things externally in the future too.