You know how they say that the internet is a series of tubes? We used to think that was just a funny old man. Turns out, it is the literal truth. The internet is made up of SVG files!
You know how they say that the internet is a series of tubes? We used to think that was just a funny old man. Turns out, it is the literal truth. The internet is made up of SVG files!
I remember when XHTML was supposed to replace HTML. Everything was going to be standardized and web designers would run their HTML code against a validator...it was going to be glorious! And of course it never happened, because demanding that all websites conform to the XHTML standard would've broken a lot of websites.
So, HTML5 ate XHTML's lunch because it was much more forgiving, and...oh yeah, you could watch videos and play games in it, too.
More precisely, both are flavors of XML.
Ok—to the extent that SVG is HTML, the variant of HTML that it is is a flavor of XML.
Technically it's not browser tolerance but spec tolerance. It's built into the html5 spec to tolerate different tags closing and other things invalid in xml.
This was an important design that grew out of one of the largest failings of xhtml that such failures would make the entire page unrenderable.
Age doesn't matter. XML is a super-set of XHTML's spec.
That is - all XHTML is valid XML but not all XML is valid XHTML.
Note I'm saying XHTML not HTML since the later need not be valid XML.
...which is derived from SGML.
litghter, as in smaller, yess. but keep in mind, that vector graphics need to be rendered, wich depending on circumstance and graphic might become inefficient.
i never crunched the numbers, but basically youre outsourcing the generation of a rastergraphic to those who open up your website.
Though this also has advantages - not only will they be drawn at an appropriate resolution, they can also be styled & modified by the user. If I'm using Dark Reader and your icons are SVGs using currentColor, they'll render with the same color as other text. The best you can do for raster graphics is inverting them.
One should always optimize assets for the web, this includes svg as well.
For critical paths I use https://optimize.svgomg.net/ a svg file optimizer. Svgs that are coming directly from illustrator or sketch are getting better these days but this little tool is invaluable regardless.
I think you can run this local too
They can include runnable JavaScript too, which can cause vulnerabilities in certain contexts. One example from work some years back: We had a web app where users could upload files, and certain users could view files uploaded by others. They had the option to download the file or, if it was a file type that the browser could display (like an image or a PDF), the site would display it directly on the page.
To prevent any XSS (scripts from user-provided files), we served all files with the CSP sandbox header, which prevents any scripts from running. However, at the time, that header broke some features of the video player on certain browsers (I think in Safari, at least), so we had to serve some file types without the header. Mistakenly, we also included image files in the exclusion, as everyone through image files couldn't contain scripts. But the MIME type for SVG files is image/svg+xml... It was very embarrassing to have such a simple XSS vuln flagged in a security audit.
Oooh, neat! [Cunningham's Law] (https://en.m.wikipedia.org/wiki/Ward_Cunningham#Cunningham's_Law) in action!
Ommigod, these kids :)
SVG comes XML (a more coherent/simple version of the SGML that is behind HTML), and specifically from a time where people took XML and made it hyper-complicated with a flurry of extensions and specifications (look up "xml namespaces" "xslt" "xml schema").
The most apparent difference between SGML and XML is than in the former you write tags like <br> without a corresponding </br>, and in the latter you have to close them like <br/> (which is shorthand for <br></br>).
So... today you learned that what you learned earlier today was close to truth, but not true :)
PS: A lot of document formats are undercover/zipped XML (eg. the libre office documents, IIRC microsoft's .xlsx and .docx). This is not dissimilar to how json/yaml are widely used today.
So, my Lemmy app - and I think a lot of Lemmy, renders markdown, so whenever you write "<...>" It disappears for me!
It all looks good now :-)
No, it's XML. It's an ancestor of HTML and, unlike HTML, it can be losslessly converted.
Not quite. XML came several years after HTML! Both are descendants of SGML.
Oh, ok.
main difference between raster graphics and vector graphics was the quality
It's not. The primitives, the most basic constitutive building blocks, are different, for raster it's the pixel (a mix of colors, e.g. red/green/blue) whereas for vector it's the ... vector (a relative position elements, e.g. line, circle, rectangle or text start with).
This is a fundamental distinction on how you interact with the content. For raster you basically paint over pixels, changing the values of pixels, whereas for vector you change values of elements and add/remove elements. Both can be lossless though (vector always is) as for raster can have no compression or lossless compression. That being said raster does have a grid size (i.e. how many pixels are stored, e.g. 800x600) whereas vector does not, letting you zoom infinitely and see no aliasing on straight lines.
Anyway yes it's fascinating. In fact you can even modify SVG straight from the browser, no image editor or text editor needed, thanks to your browser inspector (easy to change the color of a rectangle for example) or even the console itself then via JavaScript and contentDocument you can change a lot more programmatically (e.g. change the color of all rectangles).
It's a lot of fun to tinker with!
I'm not sure that lossy compression on vectors is strictly impossible.
You can do things like store less colour information and simplify splines so that curves are less complex.
True, in fact I've done so myself (simplifying a curve resulting of hand sketching). Still I'd argue that's not the expected behavior of storing the vector file but rather explicitly modifying it.
we could modify the desktop environment and make it waaaaay lighter by getting rid of jpg or png icons and just using pure svg on it
That's already happening.
You can also change the main color of many SVGs (icons or even desktop backgrounds) with one simple edit, one command, one click.
In web sites, you can assign CSS classes to SVG graphics and thus e.g. change their color according to a theme.
That's my extent of fiddling with it.
IIRC they also use fonts the same way CSS/HTML does.
BTW, there are situations where an SVG is significantly larger than a corresponding raster image. It depends on the content.
for example, on a linux distro, we could modify the desktop environment and make it waaaaay lighter by getting rid of jpg or png icons and just using pure svg on it.
Isn't that how it already works? GNOME system icons are all SVG - that's what allows them to change colors when you change themes or switch between light and dark mode.
for example, on a linux distro, we could modify the desktop environment and make it waaaaay lighter by getting rid of jpg or png icons and just using pure svg on it.
this has largely happened; if you're on a dpkg-based distro try running this command:
dpkg -S svg | grep svg$ | sort
...and you'll see that your distro includes thousands of SVG files :)
dpkg -S svg - this searches for files installed by the package manager which contain "svg" in their pathgrep svg$ - this filters the output to only show paths which end with svg; that is, the actual svg files. the argument to grep is a regular expression, where $ means "end of line". you can invert the match (to see the paths dpkg -S svg found which only contain "svg" in the middle of the path) by writing grep -v svg$ instead.sort command does what it says on the tin, and makes the output easier to readyou can run man dpkg, man grep, and man sort to read more about each of these commands.
Is this the same as pacman -Ql?
Edit: the dpkg part is.
for alpine linux users:
apk info -L $(apk info) | grep -v contains | grep 'svg'
I made an interactive map: drew in Inkscape, gave the interactive elements numbers for ids, then substituted the id='xxx' in vim with the php code and js function calls, picking up the number from the id tag and inserting it appropriately in php code and function arguments. 250 interactive elements taken care of in a single vim substitute. My bestest development power move yet :D
Hold on now. If an svg will render as valid html in browsers, does that mean I can use Inkscape as a wysiwyg webpage editor, and just export that to html?
Damn, I actually did not know that. I thought it was just an image file.
It's both of those things
Yeah, it depends on if you view source
thanks for using Leebra!
go to feed...
No, SVG files are not HTML.
Please change this post title (currently "today i learned: svg files are literally just html code"), to avoid spreading this incorrect factoid!
I suggest you change it to "today i learned: svg files are just text in an html-like language" or something like that. edit: thanks OP
SVG is a dialect of XML.
XML and HTML have many similarities, because they both are descendants of SGML. But, as others have noted in this thread, HTML is also not XML. (Except for when it's XHTML...)
Like HTML, SVG also can use CSS, and, in some environments (eg, in browsers, but not in Inkscape) also JavaScript. But, the styles you can specify with CSS in SVG are quite different than those you can specify with CSS in HTML.
Lastly, you can embed SVG in HTML and it will work in (modern) browsers. You cannot embed HTML in SVG, however.
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