Repository: flutter
Issue: [flutter_svg] InkSCape MeshGradient implementation Request
Labels: package,p: flutter_svg

_Imported from https://github.com/dnfield/flutter_svg/issues/476_

Original report by @taerilan on Jan 18, 2021

Hello there, I would like to make request for implementation of InkScape meshGradient in your package,

I believe this would be beneficial for your whole project as InkScape meshGradient gives SVG images depth, 3d illusion that brings whole SVG image to life in 3d like way.

Ive included in code below simple SVG code with meshGradient so you can check it out, couldn't upload SVG image directly, Ive also uploaded PNG image of a piano key created in InkScape with meshGradient, so you could see how it looks like.

Thought that issue with meshGradient in your package is similar to linearGradient issue, though after managing to solve linearGradient issue (when saving InkScape project as Optimized SVG, it works in your package as charm), meshGradient was still not working.
In your package I've found references for linearGradient and radialGradient, though not meshGradient, so it seems meshGradient is not implemented at all? 

Hope you will consider adding it, as it would add quality and aesthetic beauty to my and other peoples projects.

Thank


![bku](https://user-images.githubusercontent.com/15383948/104908801-ef1ac000-59c1-11eb-9ba5-104144ba64de.png) ![bkd](https://user-images.githubusercontent.com/15383948/104912450-3bb4ca00-59c7-11eb-8301-36721542f85b.png) ![bku](https://user-images.githubusercontent.com/15383948/104912512-4ff8c700-59c7-11eb-9833-de95c5275cb4.png)










```xml
<?xml version="1.0" encoding="UTF-8"?>
<svg width="76.729mm" height="124.35mm" version="1.1" viewBox="0 0 76.729 124.35" xmlns="http://www.w3.org/2000/svg" xmlns:cc="http://creativecommons.org/ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
 <defs>
  <meshgradient id="meshgradient1846" x="55.184521" y="39.6875" gradientUnits="userSpaceOnUse">
   <meshrow>
    <meshpatch>
     <stop stop-color="#fff" path="c 25.5764,0  51.1528,0  76.7292,0"/>
     <stop path="c 0,41.4514  0,82.9028  0,124.354"/>
     <stop stop-color="#fff" path="c -25.5764,0  -51.1528,0  -76.7292,0"/>
     <stop path="c 0,-41.4514  0,-82.9028  0,-124.354"/>
    </meshpatch>
   </meshrow>
  </meshgradient>
 </defs>
 <metadata>
  <rdf:RDF>
   <cc:Work rdf:about="">
    <dc:format>image/svg+xml</dc:format>
    <dc:type rdf:resource="http://purl.org/dc/dcmitype/StillImage"/>
    <dc:title/>
   </cc:Work>
  </rdf:RDF>
 </metadata>
 <g transform="translate(-55.185 -39.688)">
  <rect x="55.185" y="39.688" width="76.729" height="124.35" fill="url(#meshgradient1846)"/>
 </g>
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x,e[3*t+1][3*n+1].x=(-4*e[3*t][3*n].x+6*(e[3*t][3*n+1].x+e[3*t+1][3*n].x)+-2*(e[3*t][3*n+3].x+e[3*t+3][3*n].x)+3*(e[3*t+3][3*n+1].x+e[3*t+1][3*n+3].x)+-1*e[3*t+3][3*n+3].x)/9,e[3*t+1][3*n+2].x=(-4*e[3*t][3*n+3].x+6*(e[3*t][3*n+2].x+e[3*t+1][3*n+3].x)+-2*(e[3*t][3*n].x+e[3*t+3][3*n+3].x)+3*(e[3*t+3][3*n+2].x+e[3*t+1][3*n].x)+-1*e[3*t+3][3*n].x)/9,e[3*t+2][3*n+1].x=(-4*e[3*t+3][3*n].x+6*(e[3*t+3][3*n+1].x+e[3*t+2][3*n].x)+-2*(e[3*t+3][3*n+3].x+e[3*t][3*n].x)+3*(e[3*t][3*n+1].x+e[3*t+2][3*n+3].x)+-1*e[3*t][3*n+3].x)/9,e[3*t+2][3*n+2].x=(-4*e[3*t+3][3*n+3].x+6*(e[3*t+3][3*n+2].x+e[3*t+2][3*n+3].x)+-2*(e[3*t+3][3*n].x+e[3*t][3*n+3].x)+3*(e[3*t][3*n+2].x+e[3*t+2][3*n].x)+-1*e[3*t][3*n].x)/9,e[3*t+1][3*n+1].y=(-4*e[3*t][3*n].y+6*(e[3*t][3*n+1].y+e[3*t+1][3*n].y)+-2*(e[3*t][3*n+3].y+e[3*t+3][3*n].y)+3*(e[3*t+3][3*n+1].y+e[3*t+1][3*n+3].y)+-1*e[3*t+3][3*n+3].y)/9,e[3*t+1][3*n+2].y=(-4*e[3*t][3*n+3].y+6*(e[3*t][3*n+2].y+e[3*t+1][3*n+3].y)+-2*(e[3*t][3*n].y+e[3*t+3][3*n+3].y)+3*(e[3*t+3][3*n+2].y+e[3*t+1][3*n].y)+-1*e[3*t+3][3*n].y)/9,e[3*t+2][3*n+1].y=(-4*e[3*t+3][3*n].y+6*(e[3*t+3][3*n+1].y+e[3*t+2][3*n].y)+-2*(e[3*t+3][3*n+3].y+e[3*t][3*n].y)+3*(e[3*t][3*n+1].y+e[3*t+2][3*n+3].y)+-1*e[3*t][3*n+3].y)/9,e[3*t+2][3*n+2].y=(-4*e[3*t+3][3*n+3].y+6*(e[3*t+3][3*n+2].y+e[3*t+2][3*n+3].y)+-2*(e[3*t+3][3*n].y+e[3*t][3*n+3].y)+3*(e[3*t][3*n+2].y+e[3*t+2][3*n].y)+-1*e[3*t][3*n].y)/9}}this.nodes=e,this.colors=s}paintMesh(t,e){let 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</svg>
```


---
Comment by @dnfield on Feb 25, 2021
This would require getting Flutter to support mesh gradients upstream. I think that's probably doable.

On the web it's a bit trickier.