RNDF SplineLane::GetPositionToLane fix

[agalbachicar]

A bug was introduced as part of #6349. SplineLane::GetPositionToLane is a private method and it's used by SplineLane::do_driveable_bounds().

When the Lane belongs to a Segment with multiple Lanes, we should compute the projected GeoPosition of the Lane over the Lanes at the lateral extents of the segment. This projection is done using the curvature radius. SplineLane::GetPositionToLane is in charge of that computation.

Further test coverage for this bug will be covered in a future PR which includes the Builder.

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This change is 

[agalbachicar]

+@liangfok for feature review please.

[liangfok]

+@liangfok for feature review.

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Review status: 0 of 1 files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable

[liangfok]

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Reviewed 1 of 1 files at r1.
Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable

[sherm1]

+@sherm1 for platform review

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Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable

[sherm1]

The existence of this bug suggests that there is a missing unit test. Can you add one to this PR to verify that it is working now and to make sure no one messes this up in the future?

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Review status: all files reviewed at latest revision, 1 unresolved discussion.

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drake/automotive/maliput/rndf/spline_lane.cc, line 162 at r1 (raw file):

  // Gets the beginning and ending of the other lane, and then computes the
  // respective GeoPositions.
  const SplineLane* other_lane = static_cast<const SplineLane*>(

This should be a dynamic_cast to verify that the Lane is actually a SplineLane.

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Comments from Reviewable

[agalbachicar]

Review status: 0 of 2 files reviewed at latest revision, 2 unresolved discussions.

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drake/automotive/maliput/rndf/spline_lane.cc, line 162 at r1 (raw file):

Previously, sherm1 (Michael Sherman) wrote…

This should be a dynamic_cast to verify that the Lane is actually a SplineLane.

Done.

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drake/automotive/maliput/rndf/test/spline_lane_test.cc, line 320 at r2 (raw file):

}

// Performs geometric tests over the bounds of a pair of straight lanes.

The proposed test uses driveable_bounds() since that public call, when two or more lanes belong to the same segment, goes through the affected piece of code.

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Comments from Reviewable

[agalbachicar]

I have addressed all the comments and added a test. PTAL.

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Comments from Reviewable

[sherm1]

Great, thanks Agustin! Platform .

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Reviewed 2 of 2 files at r2.
Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable