Exported shapefile to SVG - but can't see in browser window - svg

I've exported a shapefile from PostGIS to SVG using ST_AsSVG. I chose to use relative coordinates for the export. The result of the export is here:
http://pastebin.com/rmB89Pyw
When I put this into a very simple HTML page with an SVG path element, I don't see any of the path. I"m guessing it's something to do with the viewBox/scaling/transform - but I'm not sure where to start, this is my first foray into this area.
Any ideas?

Here is a way I found to embed your shape:
<!DOCTYPE html>
<html>
<body>
<svg xmlns="http://www.w3.org/2000/svg"
width="800"
height="600"
style="border: 1px solid red">
<path
transform="translate(400,300) scale(.01, .01) translate(-323712.401, 4848647.35)"
d="... YOUR PATH ..." />
</svg>
</body>
</html>
What I did is put a "transform" attribute to (from right to left):
translate the first point of you path to 0,0
scale the path (by 0.01), I tried a few scales
translate the 0,0 (you first point) to the middle of the svg image (400, 300)
I think you can adapt this to do exactly what you want (or even make a script to extract the bounding box informations etc).

Related

Where to put <style> inside SVG?

Sorry if that might come an opinion-based, but I hope there's a right answer..
Where an inline CSS style should be placed inside an SVG document? In the
example I provide below I have defined two styles and a circle that uses them.
The first style is defined inside defs tag and the second styles is defined right inside the svg tag.
Both styles are successfully displayed on the circle (at least in Chrome they do, didn't check other browsers though).
My question is which way is more standard?
I think keeping styles in defs keeps the whole SVG more tidy. However, one can claim that I should not use defs tag since no one references the style with <use>
Thanks!
<svg height="100" width="100">
<defs id="someDefs">
<style id="style1">
.blue-fill {
fill : blue;
}
</style>
</defs>
<style id="style2">
.red-stroke {
stroke : red;
stroke-width : 12
}
</style>
<circle cx="50" cy="50" r="40" class="blue-fill red-stroke" />
</svg>
It doesn't matter. Neither approach is "more standard". <style> elements are not renderable anyway, so there is no real need to put them in the <defs> section
As commented by Paul LeBeau.
After reading this article about style on MDN, that shows an example of a style simply under the SVG root, I am more convinced it is correct to put <style> there rather than under <defs>.
Also, since <defs> tag is indeed for reusable graphical elements that should be rendered, and <style> is not a renderable element, there's no point keeping it there.
Graphical elements defined in <defs> are not rendered directly and will be rendered only with use. Hence it is always a good practice to use <defs> if the graphical object is defined for later use. It also increases the readability of the code.
More Information

SVG shape rendering dots appears

I'm making SVG effects by combining 2 identical photos with alternate slits. When you look closely, there are dotted lines 45 degree across the whole images. Referencing this question, I already tried the option shape-rendering="optimizeQuality", shape-rendering="geometricPrecision" and shape-rendering="auto" on <polygon> tags, but the dots still appears.
How do I remove the tiny dots?
Partial HTML codes (full code is too long to post here, see JSFiddle below for full CSS, JS and HTML codes):
<div class="image_wrapper">
<svg id="svg-1" class="clip-svg">
<image class="svg-image" xlink:href="http://cdn.idigitaltimes.com/sites/idigitaltimes.com/files/styles/image_embed/public/2016/09/28/pen-pineapple-apple-pen-meaning-lyrics-ppap-piko-taro-youtube-video-watch-how-do_1.jpg" width="640" height="360" />
</svg>
</div>
<div class="image_wrapper2">
<svg id="svg-2" class="clip-svg">
<image class="svg-image" xlink:href="http://cdn.idigitaltimes.com/sites/idigitaltimes.com/files/styles/image_embed/public/2016/09/28/pen-pineapple-apple-pen-meaning-lyrics-ppap-piko-taro-youtube-video-watch-how-do_1.jpg" width="640" height="360" />
</svg>
</div>
JSFiddle demo is here
The dots are caused by anti-aliasing of the polygons that you are using for the diagonal slit clipping paths.
IMO there isn't any way to prevent that. It may or may not get better if you turn anti-aliasing off with `shape-rendering="optimizeSpeed". And even if that works on one browser, it may not work on other ones.
My suggestion is to just have a complete ("un-slitted") version of the image on top. Make it invisible initially, then show it once the animation has finished.

What counts as inline-svg

I just learned that Modernizr uses two different classes for SVG support: no-svg and no-inlinesvg. I can't seem to understand the difference between the two.
According to caniuse.com, Safari 5 and below does not support inline SVG, but does support SVG. I tested this on some D3.js visualizations (them rendering SVG) and Safari 5 displays that correctly.
My first guess was that D3 produces inline SVG, but that does not seem to be the case. So I would love to hear an explanation of the difference between the two.
Inline SVG means using <svg> (and child) tags directly in your html document:
<!DOCTYPE html>
<html>
<body>
<svg width="300px" height="300px" xmlns="http://www.w3.org/2000/svg">
<text x="10" y="50" font-size="30">My SVG</text>
</svg>
</body>
</html>
SVG Support refers to the ability to understand and display SVG files using the <embed> or <object> tags.

SVG nine-slice scaling

How could one obtain nine-slice scaling in SVG?
Specifically, I'm looking for a way to define SVG objects that behave like nine-sliced objects when resized (some elements maintain their dimension, and others scale with the container).
If you meant to apply it to an svg, then the CSS3 Borders and backgrounds spec should help you do that if you reference an svg.
If you meant you wanted to do it inside an svg file, then you might be able to use a <pattern> (possibly combined with some nested <svg> elements) to do something similar. Nested <svg> elements might be another way to do this, see e.g this example. Alternatively use 9 <use> elements with different transforms, each having a different clip-path applied.
You need something like a margin around the elements that form the edges and the center, to tell them to start X pixels from the left/top to y pixels from the right/bottom. Use a foreignObject, like this:
<foreignObject width="100%" height="100px">
<div xmlns="http://www.w3.org/1999/xhtml" style="margin: 0 100px;">
<svg>
<!-- code here -->
</svg>
</div>
</foreignObject>
I wrote about methods of applying scaling grids to SVG here: http://w3.eleqtriq.com/2014/03/the-holy-grail-of-image-scaling/
Cheers, Dirk

Stretch <svg> inside an <embed> to fit window size

I am trying to stretch an svg document inside an DOM in order to fit the window size.
like so:
<div id="y">
<div id="button"> click to zoom</div>
<embed id="x" src="s17.svg" >
<script>
var btn= document.getElementById("button");
btn.addEventListener('click',function(){
var z= document.getElementsByTagName("embed")[0];
var y = z.getSVGDocument();
y.lastChild.setAttribute("viewBox","0 0 "+window.innerWidth+" "+window.innerHeight);
},false);
</script>
</div>
css:
#x{
height:100%;
width:100%;
overflow:hidden;
}
#y{
position:absolute;
top:0;
bottom:0;
left:0;
right:0;
overflow:hidden;
}
This isn't working... What am I doing wrong?
All browsers should be able to handle this just fine:
add a viewBox to the svg element (s17.svg in your example) without using script if possible
remove the width and height attributes on the svg element if they are specified
add an attribute preserveAspectRatio="none" to the svg element to make it stretch even if the css-viewport aspect ratio doesn't match the viewBox aspect ratio.
set the width/height of the embed/iframe/object to whatever you want and the svg will automatically stretch to fit
If you don't want stretching then you can also do preserveAspectRatio="xMidYMid slice" (fill whole viewport, slicing away parts if necessary) or preserveAspectRatio="xMidYMid meet" (this is the default, center the svg in the viewport and maintain the aspect ratio).
All browsers handle SVG support completely differently. I think your best bet is to use an object tag instead of embed, and you still have to do some hacking to get it to look right on each browser. This link and this link have some useful information for getting it to work cross-browser.

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