Expose additional properties on hole/pad connectors

[follower]

For a given connector (from .connectHoles, i.e. holes and pads, as created in ._buildDepthHoles()) we want the following properties exposed (via .userData):

• Element name (already available via .userData.element?)
• Pad/Pin name
• Mirrored? or Top/Bottom Layer? [Not to be specifically handled currently (see here).]
• Signal name (Is only one signal ever connected per pin?) [see Expose signal name as connector property #40]

[follower]

Viewing in the JS Console the Sparkfun redstick from examples/complex.html as an example:

> brd.connectHoles[66].userData

Object {drill: pad, element: element}

(Note: Not all items in .connectHoles have userData.)

> brd.connectHoles[66].userData.drill

<pad name="4" x="7.62" y="0" drill="1.016" diameter="1.8796" rot="R90"/>

So, the pad/pin name can be retrieved via:

> brd.connectHoles[66].userData.drill.getAttribute("name")

"4"

The parent element (which seems to originate from .userData.drill.elementParent) can be retrieved via:

> brd.connectHoles[66].userData.element

<element name="JP8" library="SparkFun-Connectors" package="1X04_NO_SILK_ALL_ROUND" value="DNP" x="12.7" y="1.27" rot="R180"/>

So, the associated element name can be retrieved via:

> brd.connectHoles[66].userData.element.getAttribute("name")

"JP8"

[follower]

Apparently connectors have changed to not be placed on both top and bottom side individually, so it may be unnecessary to specify this in the name with the latest code.

[dave5]

top and bottom connectors are a premature optimisation. lets just got for a single connector positioned at the mid-plane

[follower]

It seems that top/bottom connectors are currently treated differently anyway (only the top hole gets the elementParent property added to it):

Eagle-Loader/src/eagle-brd-renderer.js

Line 773 in 6c576a7

connector.userData.drill = drills[ i ];

FWIW it's not immediately obvious if there's any Eagle-related functionality that requires two connectors per hole so until we run into anything I can continue with the practice of treating the top connection as canonical.

@dave5 are you able to push your single-connector version of the code? (Assuming I understood you correctly and such a modified version exists.)

[follower]

Given the primary goal of this ticket is to expose element & pin names for use with #38 it seems like this doesn't actually require additional functionality as these properties are already exposed.

Is there a need to expose these properties by a simpler mechanism than the current approach? i.e.

• Element name: .userData.element.getAttribute("name")
• Pin name: .userData.drill.getAttribute("name")

Note that currently the drill property does not exist for all elements in .connectHoles since it is not added to the bottom-side connectors.

Given that we didn't already "know" these values were exposed, I wonder if this suggests at some point we need a better way of implementing/documenting what is stored in .userData?

[follower]

(Oh, I remember now, I wondered if a stackable Arduino shield style-header (e.g. https://www.adafruit.com/product/85) would be a situation where separate top/bottom Connectors might be required.)

[follower]

Once the PRs listed in #38 & #40 are merged this issue (and the two related issues) can be closed.