support svg defining currentColor without color

[Klumbumbus]

The first was added in wiki:Maps/Argentina?action=diff&version=86

data:image/svg+xml;base64,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

and is displayed fine at least in Firefox. It decodes to:

<svg class="svg-inline--fa fa-download fa-w-16" aria-hidden="true" data-fa-processed="" data-prefix="fas" data-icon="download" role="img" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512"><path fill="currentColor" d="M216 0h80c13.3 0 24 10.7 24 24v168h87.7c17.8 0 26.7 21.5 14.1 34.1L269.7 378.3c-7.5 7.5-19.8 7.5-27.3 0L90.1 226.1c-12.6-12.6-3.7-34.1 14.1-34.1H192V24c0-13.3 10.7-24 24-24zm296 376v112c0 13.3-10.7 24-24 24H24c-13.3 0-24-10.7-24-24V376c0-13.3 10.7-24 24-24h146.7l49 49c20.1 20.1 52.5 20.1 72.6 0l49-49H488c13.3 0 24 10.7 24 24zm-124 88c0-11-9-20-20-20s-20 9-20 20 9 20 20 20 20-9 20-20zm64 0c0-11-9-20-20-20s-20 9-20 20 9 20 20 20 20-9 20-20z"></path></svg>

• It is not displayed within JOSM
• SyncEditorLayerIndex.java#L1083 doesn't support it too

[Don-vip]

Error in logs:

2019-08-31 13:19:36.589 WARNING: Could not parse path svgSalamander:/currentColor
java.net.MalformedURLException: unknown protocol: svgsalamander
	at java.net.URL.<init>(URL.java:600)
	at java.net.URL.<init>(URL.java:490)
	at java.net.URL.<init>(URL.java:439)
	at java.net.URI.toURL(URI.java:1089)
	at com.kitfox.svg.SVGUniverse.getElement(SVGUniverse.java:345)
	at com.kitfox.svg.SVGUniverse.getElement(SVGUniverse.java:310)
	at com.kitfox.svg.ShapeElement.renderShape(ShapeElement.java:163)
	at com.kitfox.svg.Path.render(Path.java:94)
	at com.kitfox.svg.Group.render(Group.java:205)
	at com.kitfox.svg.SVGRoot.render(SVGRoot.java:335)
	at com.kitfox.svg.SVGRoot.renderToViewport(SVGRoot.java:266)
	at com.kitfox.svg.SVGDiagram.render(SVGDiagram.java:111)
	at org.openstreetmap.josm.tools.ImageProvider.createImageFromSvg(ImageProvider.java:1671)
	at org.openstreetmap.josm.tools.ImageResource.getImageIcon(ImageResource.java:163)
	at org.openstreetmap.josm.tools.ImageResource.getImageIconBounded(ImageResource.java:276)
	at org.openstreetmap.josm.tools.ImageResource.getImageIconBounded(ImageResource.java:229)
	at org.openstreetmap.josm.tools.ImageResource.attachImageIcon(ImageResource.java:104)
	at org.openstreetmap.josm.actions.AddImageryLayerAction.lambda$1(AddImageryLayerAction.java:83)
...
	at org.openstreetmap.josm.tools.ImageProvider.getResourceAsync(ImageProvider.java:749)
	at org.openstreetmap.josm.actions.AddImageryLayerAction.<init>(AddImageryLayerAction.java:81)
	at org.openstreetmap.josm.gui.ImageryMenu.refreshImageryMenu(ImageryMenu.java:173)

[stoecker]

In 15326/josm:

see #18102 - better support for data: url images

[stoecker]

To me the fill="currentColor" looks very strange. Is this really correct? I'd say JOSM is right and the image needs to be fixed.

[stoecker]

It is an HTML+SVG interlinking method. As we have no HTML here it makes little sense. currentColor should simply be replaced by a proper color definition for the JOSM use case.

[Klumbumbus]

It could fall back to e.g. black.

[stoecker]

Yeah, but why support it in the first place? Changing the image is the better solution.

[Don-vip]

This has nothing to do with base64.

currentColor is valid, as per ​https://www.w3.org/TR/SVG11/painting.html#SpecifyingPaint

Indicates that painting is done using the current animated value of the color specified by the ‘color’ property. This mechanism is provided to facilitate sharing of color attributes between parent grammars such as other (non-SVG) XML. This mechanism allows you to define a style in your HTML which sets the ‘color’ property and then pass that style to the SVG user agent so that your SVG text will draw in the same color.

svgSalamander supports it:

        if (styleAttrib.getStringValue().equals("currentColor"))
        {
            StyleAttribute currentColorAttrib = new StyleAttribute();
            if (getStyle(currentColorAttrib.setName("color")))
            {
                if (!currentColorAttrib.getStringValue().equals("none"))
                {
                    return currentColorAttrib.getColorValue();
                }
            }
            return null;
        }

But the SVG is invalid as it doesn't define any color. It must be fixed.

[stoecker]

Replying to Don-vip:

This has nothing to do with base64.

currentColor is valid, as per ​https://www.w3.org/TR/SVG11/painting.html#SpecifyingPaint

Indicates that painting is done using the current animated value of the color specified by the ‘color’ property. This mechanism is provided to facilitate sharing of color attributes between parent grammars such as other (non-SVG) XML. This mechanism allows you to define a style in your HTML which sets the ‘color’ property and then pass that style to the SVG user agent so that your SVG text will draw in the same color.

svgSalamander supports it:

        if (styleAttrib.getStringValue().equals("currentColor"))
        {
            StyleAttribute currentColorAttrib = new StyleAttribute();
            if (getStyle(currentColorAttrib.setName("color")))
            {
                if (!currentColorAttrib.getStringValue().equals("none"))
                {
                    return currentColorAttrib.getColorValue();
                }
            }
            return null;
        }

But the SVG is invalid as it doesn't define any color. It must be fixed.

Hmm. I don't understand this comment. "currentColor" is defined outside the SVG, which we don't have, as there is no "outside" in our case.

[Klumbumbus]

SVG fixed: wiki:Maps/Argentina?action=diff&version=91

[Don-vip]

Replying to stoecker:

Hmm. I don't understand this comment. "currentColor" is defined outside the SVG, which we don't have, as there is no "outside" in our case.

I understand all the "parent grammar" stuff as an additional possibility of the simple case where a parent SVG tag defines the color property (which is what svgSalamander expects).

[stoecker]

Replying to Don-vip:

Replying to stoecker:

Hmm. I don't understand this comment. "currentColor" is defined outside the SVG, which we don't have, as there is no "outside" in our case.

I understand all the "parent grammar" stuff as an additional possibility of the simple case where a parent SVG tag defines the color property (which is what svgSalamander expects).

So essentially you also suppose to replace currentColor with a fixed definition for this image?

[Don-vip]

I suppose nothing, I just see this image is not compatible with what svgSalamander expects, thus needed to be changed, and Stefan changed it :)