How to correctly collect pictures in the project?

Question

css

Good afternoon!
Please share your experience in assembling front projects.
I'm interested in how the pictures are assembled.
I looked at a lot of lessons and different templates... few places support sprites from dpi.
If you have implemented this correctly, share your ideas, I will be very grateful.
What specifically interests:
1 sprite assembly with support for various dpi --- if it is still relevant
2 inserting svg icons into html from a sprite
3 how to insert svg as a background? --- this is a very important question... (so that there are no unnecessary requests to the server)
Thank you all!

Answer 1

Depending on the tasks
1. gulp.spritesmith - collects png into one sprite
2. gulp-svg-sprite - collects svg into one sprite
3. Inserting svg sprites into the page
Now it may not be relevant anymore, but it has not taken root in my practice
Background svgs (bad cross-browser compatibility, cannot be styled from external styles)
base64 (Burning layout, the picture has changed - in all places you need to change the picture everywhere, I use it very rarely)
Inserting svg sprites on the page, I do it according to this practice:
On the page I make a container where I group all the sprites

<div data-ui="resources" style="display: none;">
   <svg data-ui="icon-pack">
      <g id="svg-search"><path d="M61.8,56.6l-15.1-15C50,37.2,52,31.8,52,26C52,11.7,40.3,0,26,0C11.7,0,0,11.7,0,26c0,14.3,11.7,26,26,26 c6,0,11.5-2,15.9-5.4l15,15L61.8,56.6z M26,44.9c-10.5,0-19-8.5-19-19C7,15.5,15.5,7,26,7c10.5,0,19,8.5,19,19 C45,36.4,36.4,44.9,26,44.9z"></path></g>
      <g id="svg-img"><path d="M0.8,0C0.4,0,0,0.4,0,0.8v22.9c0,0.4,0.4,0.8,0.8,0.8h24.7c1.2,1.5,3,2.5,5,2.5c3.5,0,6.4-2.9,6.4-6.5c0-2.7-1.7-5.1-4-6.1V0.8C33,0.4,32.6,0,32.2,0H0.8z M1.6,1.6h29.8V14c-0.3,0-0.5-0.1-0.8-0.1c-1.2,0-2.3,0.4-3.3,0.9l-3-3.2c-0.2-0.2-0.4-0.3-0.7-0.2 c-0.2,0-0.3,0.1-0.5,0.2l-5.7,5.1l-7.2-8.3c-0.2-0.2-0.5-0.3-0.7-0.3c-0.2,0-0.3,0.1-0.5,0.2l-7.5,7.9V1.6z M17.7,3.3 c-1.8,0-3.2,1.5-3.2,3.3c0,1.8,1.4,3.3,3.2,3.3c1.8,0,3.2-1.5,3.2-3.3C20.9,4.7,19.5,3.3,17.7,3.3z M17.7,4.9 c0.9,0,1.6,0.7,1.6,1.6c0,0.9-0.7,1.6-1.6,1.6c-0.9,0-1.6-0.7-1.6-1.6C16.1,5.6,16.8,4.9,17.7,4.9z M9.6,10.2l11.1,12.7H1.6v-4.2 L9.6,10.2z M23.7,13.4l2.3,2.5c-1.1,1.2-1.9,2.8-1.9,4.6c0,0.9,0.2,1.7,0.5,2.5h-1.7L18.6,18L23.7,13.4z M30.6,15.5 c2.7,0,4.8,2.2,4.8,4.9c0,2.7-2.2,4.9-4.8,4.9s-4.8-2.2-4.8-4.9C25.7,17.7,27.9,15.5,30.6,15.5z M30.6,16.8c-0.4,0-0.8,0.4-0.8,0.8 v2h-2c-0.4,0-0.8,0.4-0.8,0.8c0,0.5,0.4,0.8,0.8,0.8h2v2c0,0.5,0.4,0.8,0.8,0.8c0.4,0,0.8-0.4,0.8-0.8v-2h2c0.4,0,0.8-0.4,0.8-0.8 c0-0.5-0.4-0.8-0.8-0.8h-2v-2C31.4,17.1,31,16.8,30.6,16.8z"></path></g>
      <g id="svg-plus"><path d="M15.6,7.1l-5.1,0c0,0,0,0-0.1,0c0,0,0,0-0.1,0c-0.2,0-0.4-0.2-0.4-0.5l0,0l0-5.1l0-0.3C9.8,0.6,9.2,0,8.5,0 C7.7,0,7.1,0.6,7.1,1.3l0,0.2l0,5.1c0,0,0,0,0,0c0,0,0,0,0,0c0,0,0,0,0,0c0,0,0,0,0,0c0,0.3-0.2,0.5-0.5,0.5c0,0,0,0,0,0 c0,0,0,0,0,0l-5,0l-0.3,0C0.6,7.1,0,7.7,0,8.5c0,0.7,0.6,1.4,1.3,1.4h0.2l5.1,0c0,0,0,0,0,0c0,0,0,0,0,0c0,0,0,0,0,0 c0.3,0,0.5,0.2,0.5,0.5c0,0,0,0,0,0c0,0,0,0,0,0c0,0,0,0,0,0c0,0,0,0,0,0l0,5.1l0,0.2C7.2,16.4,7.8,17,8.5,17 c0.8,0,1.4-0.6,1.4-1.4l0,0l0-5.2c0,0,0,0,0,0c0,0,0,0,0,0c0-0.3,0.2-0.5,0.5-0.5l0,0l5.1,0l0.2,0C16.4,9.9,17,9.2,17,8.5 C17,7.7,16.4,7.1,15.6,7.1L15.6,7.1z"></path></g>
   </svg>
</div>

In the document I use it like this (for svg I pass the sprite id in the xlink:href="..." attribute):

<button data-ui="search">
   <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 61.8 61.5"><use x="0" y="0"  xlink:href="#svg-search"></use></svg>
</button>

As for rasta and dpi, I use 2 types of sprite for each icon (regular monitor and retina).
If support for 3 or more density types is required, svg is used.
But mostly for mobile devices (example 120dpi) I use retina sprites, I didn’t notice any problems with the quality of the icon, the only traffic volume for icons increases to ~ 5-10%