shift_section_view_elevations

Code Template

var sampleLineGroupHandle = "SAMPLE_LINE_GROUP_HANDLE";
var sectionViewGroupName = "";
var mode = "shift";
var delta = 0.0;
var clearance = 0.0;
var referenceSourceHandle = "";
var height = 0.0;
var startStation = double.NaN;
var endStation = double.NaN;

var isHandle = new Func<string, bool>(value =>
    !string.IsNullOrWhiteSpace(value)
    && System.Text.RegularExpressions.Regex.IsMatch(value, "^[0-9A-Fa-f]{1,16}$"));
if (!isHandle(sampleLineGroupHandle))
    return new { success = false, error = "sampleLineGroupHandle must be a hexadecimal handle." };
if (mode != "shift" && mode != "belowLowest")
    return new { success = false, error = "mode must be \"shift\" or \"belowLowest\"." };
if (mode == "shift" && (!double.IsFinite(delta) || delta == 0 || Math.Abs(delta) > 1000))
    return new { success = false, error = "Shift mode needs a nonzero delta of at most 1000." };
if (mode == "belowLowest" && (!double.IsFinite(clearance) || clearance < 0 || clearance > 1000 || !isHandle(referenceSourceHandle)))
    return new { success = false, error = "belowLowest mode needs a clearance of 0..1000 and a referenceSourceHandle." };
if (!double.IsFinite(height) || height < 0 || height > 1000 || (height > 0 && mode != "belowLowest"))
    return new { success = false, error = "height must be 0..1000 and is only used in belowLowest mode." };
if (double.IsInfinity(startStation) || double.IsInfinity(endStation) || sectionViewGroupName == null)
    return new { success = false, error = "startStation and endStation must be finite or NaN." };

ObjectId? ResolveId(string handle)
{
    try { return Database.GetObjectId(false, new Handle(System.Convert.ToInt64(handle, 16)), 0); }
    catch { return null; }
}

var groupId = ResolveId(sampleLineGroupHandle);
var group = groupId.HasValue ? Transaction.GetObject(groupId.Value, OpenMode.ForRead) as SampleLineGroup : null;
if (group == null || group.IsErased)
    return new { success = false, error = "sampleLineGroupHandle must identify an existing sample line group." };

var viewGroups = group.SectionViewGroups.Cast<SectionViewGroup>().ToList();
var matching = sectionViewGroupName == ""
    ? viewGroups
    : viewGroups.Where(g => g.Name.Equals(sectionViewGroupName, StringComparison.OrdinalIgnoreCase)).ToList();
if (matching.Count != 1)
    return new {
        success = false,
        error = sectionViewGroupName == "" ? "The sample line group has several section view groups; name one." : "No single section view group has this name.",
        available = viewGroups.Select(g => new { g.Name, g.IsIndividual, viewCount = g.GetSectionViewIds().Count }).ToList()
    };
var viewGroup = matching[0];

ObjectId referenceSourceId = ObjectId.Null;
if (mode == "belowLowest")
{
    var id = ResolveId(referenceSourceHandle);
    // GetSectionSources needs the group open for write; on a read-open group
    // Civil 3D 2025 ends with a fatal eNotOpenForWrite. Nothing is changed.
    group.UpgradeOpen();
    foreach (SectionSource source in group.GetSectionSources())
        if (id.HasValue && source.SourceId == id.Value && source.IsSampled) referenceSourceId = id.Value;
    if (referenceSourceId.IsNull)
        return new { success = false, error = "referenceSourceHandle must be a sampled section source of this sample line group." };
}

// Plan every view first; nothing is written unless all can be changed.
var plan = new List<(ObjectId viewId, string name, double station, double oldMin, double oldMax, double newMin, double newMax, double referenceTop, bool wasAutomatic)>();
foreach (ObjectId viewId in viewGroup.GetSectionViewIds())
{
    var view = (SectionView)Transaction.GetObject(viewId, OpenMode.ForRead);
    var line = (SampleLine)Transaction.GetObject(view.SampleLineId, OpenMode.ForRead);
    if ((!double.IsNaN(startStation) && line.Station < startStation - 1e-6)
        || (!double.IsNaN(endStation) && line.Station > endStation + 1e-6)) continue;
    var oldHeight = view.ElevationMax - view.ElevationMin;
    if (!double.IsFinite(oldHeight) || oldHeight <= 0)
        return new { success = false, error = $"View '{view.Name}' has no valid elevation range." };
    double newMin;
    var referenceTop = double.NaN;
    if (mode == "shift")
    {
        newMin = view.ElevationMin + delta;
    }
    else
    {
        var sectionId = line.GetSectionId(referenceSourceId);
        var section = sectionId.IsNull ? null : Transaction.GetObject(sectionId, OpenMode.ForRead) as Autodesk.Civil.DatabaseServices.Section;
        if (section == null || !double.IsFinite(section.MinmumElevation) || Math.Abs(section.MinmumElevation) > 1e6
            || !double.IsFinite(section.MaximumElevation) || Math.Abs(section.MaximumElevation) > 1e6)
            return new { success = false, error = $"View '{view.Name}': the reference section has no usable elevation range.", station = line.Station };
        newMin = section.MinmumElevation - clearance;
        referenceTop = section.MaximumElevation;
    }
    // A sheet height replaces the view's own height; otherwise the height is kept.
    var newMax = newMin + (height > 0 ? height : oldHeight);
    plan.Add((viewId, view.Name, line.Station, view.ElevationMin, view.ElevationMax, newMin, newMax, referenceTop, view.IsElevationRangeAutomatic));
}
if (plan.Count == 0)
    return new { success = false, error = "No section views in the given station range." };

var changed = new List<object>();
foreach (var item in plan.OrderBy(p => p.station))
{
    var view = (SectionView)Transaction.GetObject(item.viewId, OpenMode.ForWrite);
    view.IsElevationRangeAutomatic = false;
    // Move the limit in the direction of travel first so min stays below max.
    if (item.newMin > item.oldMin)
    {
        view.ElevationMax = item.newMax;
        view.ElevationMin = item.newMin;
    }
    else
    {
        view.ElevationMin = item.newMin;
        view.ElevationMax = item.newMax;
    }
    if (Math.Abs(view.ElevationMin - item.newMin) > 1e-6 || Math.Abs(view.ElevationMax - item.newMax) > 1e-6)
        throw new InvalidOperationException($"View '{item.name}' did not accept the new elevation range.");
    changed.Add(new {
        item.name,
        handle = view.Handle.ToString(),
        item.station,
        oldMin = item.oldMin,
        oldMax = item.oldMax,
        newMin = view.ElevationMin,
        newMax = view.ElevationMax,
        height = view.ElevationMax - view.ElevationMin,
        referenceTop = double.IsNaN(item.referenceTop) ? (double?)null : item.referenceTop,
        referenceFits = double.IsNaN(item.referenceTop) ? (bool?)null : item.referenceTop <= view.ElevationMax + 1e-6,
        item.wasAutomatic
    });
}
// Views whose reference section rises above the new top; written anyway, reported for review.
var notFitting = plan.Where(p => !double.IsNaN(p.referenceTop) && p.referenceTop > p.newMax + 1e-6)
    .OrderBy(p => p.station)
    .Select(p => new { p.name, p.station, referenceTop = p.referenceTop, top = p.newMax, missing = p.referenceTop - p.newMax })
    .ToList();

return new {
    success = true,
    viewGroup = new { name = viewGroup.Name, viewCount = viewGroup.GetSectionViewIds().Count },
    mode,
    delta = mode == "shift" ? delta : (double?)null,
    clearance = mode == "belowLowest" ? clearance : (double?)null,
    height = height > 0 ? height : (double?)null,
    changedCount = changed.Count,
    notFittingCount = notFitting.Count,
    notFitting,
    views = changed
};