[Feature request] Export as SVG

[Jolanrensen]

[Feature request] Export as SVG

[Jolanrensen]

I started working on it here https://github.com/Jolanrensen/data2viz/tree/svg-export
It's a first draft, but some basic things seem to work already!
Gradients don't work yet, images probably never will work and I've still got some render issues with entire plots (I probably missed some attributes), but, it's a start :)
Will continue with it later

[gzoritchak]

I created a branch with a first commit to initiate the work: https://github.com/data2viz/data2viz/compare/svg-export

[gzoritchak]

I merged the current work, and I'm going to release it in version 0.8.17.

We'll have to wait for the HeadlessVizContainer to implement the export for VizContainer (to do some tests).

[gzoritchak]

In fact, there is no need to create a per-platform code. The idea is to generate an SVG string representing the whole node tree. This can be done in the common code with an extension on Viz:

fun Viz.toSvg(): String {
  //...
} 

The first implementation of data2viz was based on D3JS and used SVG. The initial code can be used as an inspiration on how to do the transformation from nodes to SVG string: https://github.com/data2viz/data2viz/blob/aa1f9a3b2ffa1babc470569a95405fb51a9e17bb/viz/d2v-viz-js/src/main/kotlin/io/data2viz/viz/SvgViz.kt

[Jolanrensen]

I agree. In theory an SVG is nothing more than a string, so no platformspecific code is needed, although having a SVG building library could save us some time. I did find https://github.com/nwillc/ksvg, but it hasn't been updated in a while so I guess we'll have to do it ourself. I'll see what I can do in my spare time, because it does seem very doable indeed :)

[Jolanrensen]

I created a branch with a first commit to initiate the work: https://github.com/data2viz/data2viz/compare/svg-export

Small question: How efficient should it be? It might be a lot less error-prone to use a class with maps to represent an "SvgComponent", but I can understand this would result in a lot of overhead compared to simply using a string builder... I'll try to figure out something clever yet fast.

[gzoritchak]

The goal is to generate an export from a visualization. The exported SVG will be a subset of the SVG elements and attributes. So the code doesn't have to represent all the possible attributes. You can write idiomatic clever but simple code ;-).

[LouisCAD]

I think we can close this issue as the latest released fixed most text rendering problems, and added support to generate SVG out of a VizContainer?