Dash pattern to penstyle

[Kanahiro]

{
    "stroke": "solid", // nopen | solid | dash | dot | dashdot | dashdotdot | customdash
    "cap": "square",
    "join": "bevel"
}

if stroke is not nopen or solid, it is good to assign dash to "stroke" and add dash_pattern prop as following:

"dash_pattern": [2, 1, 4, 2]

To be generic, it is better to treat dash | dot | dashdot | dashdotdot | customdash in one logic. We may be able to translate like: dash -> [5, 2] dot -> [1, 2] dashdot -> [4, 1, 2, 1] dashdotdot -> [4, 1, 2, 1, 2, 1]

Then my proposal is:

{
    "stroke": "solid", // nopen | solid | dash
    "cap": "square",
    "join": "bevel"
    "dash_pattern": [5, 2] // added only when stroke is dash
}

[bordoray]

Looks to become pretty simplier! Should be careful about size translation, which should be close to map portraying. Let me investigate a bit, I will teply today

[Kanahiro]

I mean:

• dash (preset)

• custom dash: [1.4, 0.7]

[Kanahiro]

We can convert any units to point!

[bordoray]

I am suspecting dash size to be linked to stroke size. Let me check.

[bordoray]

It looks to be no precision about preset Dash patterns size:

• https://doc.qt.io/qt-6/qt.html#PenStyle-enum

Here is my estimation after measurements, considering stroke_width = s

Dash line : [4s, 2s]
Dot line : [1s, 2s]
Dash dot line : [4s, 2s, 1s, 2s]
Dash dot dot line :  [4s, 2s, 1s, 2s, 1s, 2s]