SPUI - Feedback welcome

[timl2k12]

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This is my first shot at creating a SPUI according to the style guide. I think I got it all right. I wish I had taken a screenshot of the way it was before (on second thought I guess you can see that in the live map), but I think this is definitely an improvement.

[AlanOfTheBerg]

Looks really good to me. A couple items:

1. Southbound exit 6A doesn't have a colon in the name per naming standard for exits.
2. The two segments of Waters under the freeway each have an extra geometry node which isn't needed.
3. On the northbound side, would it make sense to extended the two ramps segments for the west/east-bound onto Waters back to the toll booth so that drivers can get instructions to get into the left/right side of the plaza ahead of time? Or is it safe/slow enough after going through the plaza to get into the correct lane after? (I go through the left side of the plaza but then need to turn right onto Waters, for example.)
4. Can this SPUI be used to do a u-turn onto the freeway? Some SPUI interchanges allow use of the offramp-to-onramp move to get back onto the freeway going the other direction. If so, that's just another turn restriction to open up.

[CBenson]

I would raise one issue that I don't see addressed in the wiki and is applicable to all ramps with splits at the end. If there is a sharp turn at the end of the ramp to the road you should get a "turn" instruction. If there is a slight turn at the end of ramp to the road you get no instruction. Thus, if exiting I-97 here if turning left on Quarterfield Rd, you get an instruction to "Exit right at Exit 13: MD-174 Quarterfield Rd," an instruction to "stay left to MD-174 W Severna" (if exiting from I-97 N) and an instruction to "turn left at Quarterfield Rd." If you are turning right on Quarterfield Rd, you only get the exit instruction and the stay instruction: you get no "turn right at Quarterfield Rd" instruction.

I'm not sure whether you want both stay and turn at W Waters road instructions. But the basic problem is that the angles are so close to 45 degrees that I'm not sure whether you will get the turn instructions or not at the end of the ramps.

[AlanOfTheBerg]

I'm not sure whether you want both stay and turn at W Waters road instructions. But the basic problem is that the angles are so close to 45 degrees that I'm not sure whether you will get the turn instructions or not at the end of the ramps.

Good points. Now that I look at angles more closely, the westbound Waters onramp to NB 589 might give a turn, but it's counterpart on eastbound Waters onramp to SB 589 may give a "turn" instruction.

Also, FYI, and there's nothing you can do about this, because Waters is defined as a highway, you can only get "exit" instructions for any slight-angled segment coming from it. It looks like most of those angles will give a "turn" command based on the angle being closer to 90 degrees.

[timl2k12]

Thanks for the feedback! My responses in red.

1. Southbound exit 6A doesn't have a colon in the name per naming standard for exits. FIXED
2. The two segments of Waters under the freeway each have an extra geometry node which isn't needed. FIXED
3. On the northbound side, would it make sense to extended the two ramps segments for the west/east-bound onto Waters back to the toll booth so that drivers can get instructions to get into the left/right side of the plaza ahead of time? Or is it safe/slow enough after going through the plaza to get into the correct lane after? (I go through the left side of the plaza but then need to turn right onto Waters, for example.) Nice catch. The toll lane you go through will depend on which one(s) are open and whether or not you use cash or "SunPass" (e-Toll) (See attachment)

Toll configuration

SunPass.jpg (105.12 KiB) Viewed 90 times

4. Can this SPUI be used to do a u-turn onto the freeway? Some SPUI interchanges allow use of the offramp-to-onramp move to get back onto the freeway going the other direction. If so, that's just another turn restriction to open up. Uturns are not allowed.

[timl2k12]

I'm not sure whether you want both stay and turn at W Waters road instructions. But the basic problem is that the angles are so close to 45 degrees that I'm not sure whether you will get the turn instructions or not at the end of the ramps.

Good points. Now that I look at angles more closely, the westbound Waters onramp to NB 589 might give a turn, but it's counterpart on eastbound Waters onramp to SB 589 may give a "turn" instruction.

Also, FYI, and there's nothing you can do about this, because Waters is defined as a highway, you can only get "exit" instructions for any slight-angled segment coming from it. It looks like most of those angles will give a "turn" command based on the angle being closer to 90 degrees.

So ultimately they should be as close to 90 degrees as possible to avoid stay on waters commands is what I think the import is.
EDIT: This is fixed now with little 90 degree hooks as suggested by the style manual.

[timl2k12]

If you are turning right on Quarterfield Rd, you only get the exit instruction and the stay instruction: you get no "turn right at Quarterfield Rd" instruction.

I'm not sure I see the issue, since if you are going right in this case, you are basically merging with traffic and following the ramp onto the road and not going across traffic, whereas if you are going left you are likely going thru a traffic light and making a sharp left turn across traffic.

[CBenson]

I'm not saying there is issue per se with the Quarterfield Rd interchange. I'm just using it to illustrate that the merge gives no turn instruction while the sharp left gives a "turn left" instruction. In your example, the angles are so close to 45 degrees, I don't whether waze will treat them as a merge with no instruction or treat them as sharp turn and give the "turn" instruction.

[timl2k12]

I'm not saying there is issue per se with the Quarterfield Rd interchange. I'm just using it to illustrate that the merge gives no turn instruction while the sharp left give a "turn left" instruction. In your example, the angles are so close to 45 degrees, I don't whether waze will treat them as a merge with no instruction or treat them as sharp turn and give the "turn" instruction.

Got it. I see what you are saying. The style manual leaves this unaddressed. I've adjusted the angles for the intended outcome.
EDIT: Here is the tweak I ended up making (among others).

SPUI tweak

SPUI tweak.jpg (18.81 KiB) Viewed 70 times

[AlanOfTheBerg]

3. On the northbound side, would it make sense to extended the two ramps segments for the west/east-bound onto Waters back to the toll booth so that drivers can get instructions to get into the left/right side of the plaza ahead of time? Or is it safe/slow enough after going through the plaza to get into the correct lane after? (I go through the left side of the plaza but then need to turn right onto Waters, for example.) Nice catch. The toll lane you go through will depend on which one(s) are open and whether or not you use cash or "SunPass" (e-Toll) (See attachment)

SunPass.jpg

Hmmm... So no real use to extending the ramps then you still may need to change lanes after.