So, the bounty that Benchoff has put on a tutorial like this would help me move my projects forward and pay some bills. Since I'm currently unemployed, I put on my robe and a wizard hat - and dive into a vat of something smelling of frustration and bad UX, hoping that this goal is not located too deep and my tank of patience will not run out at the wrong moment. I hope to get better at Inkscape along the way, too.
Update: it wasn't that bad, and I learned a lot about Inkscape, Fritzing and SVGs along the way. A day and a half well-spent!
This tutorial is a tutorial from scratch - I'm not referring to any existing tutorials. Just downloading Fritzing, understanding how the parts work and creating my own part from zero.
We're aiming for a simple schematic symbol - a rectangle, pins from both sides matching the physical pinout and text labels with those.
New Inkscape document:
Canvas dimensions:
Width: 1 inch
Height: (number of pins from one side + 1 )*0.1, for our ATtiny it's 5*0.1 = 0.5
IC body:
Draw a rectangle, no fill, black outline with 1px stroke width. Dimension it to 0.5x0.5in and center.
IC pins:
Draw a straight line, set width to 0.25 in and height to something like 0.012. Move first row of lines to X:0.0in and Y:(0.1, 0.2, 0.3, 0.4)in. Second row goes to X:0.75in and same Y.
The SVG we'll need to draw will be a little larger though to look nice and be perfectly aligned with the grid. Let's say pin rectangle height will be 0.035.
Modifications:
IC dimensions (with pins): add 0.04 to width amd height
IC body dimensions - multiply pin rectangle height by 2 and subtract that from IC body height, body width stays the same
The footprint I got minified is a good template. I could just put "ATtiny85" into "ic_text"... come to think of it, it's already there. However, let's make it from scratch! There'll be issues like grid sizes and dimensions and it would be unfair not to get those sorted out.
Woke up, continuing work. Does the size even matter? I measured the real Tiny's dimensions and they weren't to scale with the SVG. Let's scale our ATtiny85 in Inkscape to those dimensions and find out:
Well. First of all, I enlarged that footprint but it shrinked. Second thing - Inkscape fucks up the SVG, making it unreadable:
Nothing's better than reverse-engineering, right? Well, maybe I can actually learn something from the existing parts, especially provided there are so many DIP-8 ICs shipped with Fritzing. I'm creating everything from scratch, but this saves my frustration for me and time for readers.
Fritzing is huge - 182MB archived, 360MB unpacked. I can go make hot chocolate while the archive is unpacking.