ZoomXref

ZoomXref.lsp summary

• Purpose: Display a dialog listing Xrefs and zoom the view to the combined bounding box of the selected Xref inserts in Model Space.
• Key idea: LIVE wildcard filtering updates the list while typing, then ActiveX ZoomWindow zooms precisely to the Xref LL and UR corners.

Commands

• ZOOMXREF Opens the Xref selection dialog with live filter, Units and Layer columns, plus OK, Apply, Cancel, Help.
• SELECTXREF Alias that runs ZOOMXREF.
• Apply Zooms without closing the dialog.
• OK Zooms and closes the dialog.

What it does

• Collect Xrefs: Scans BlockTableRecords where IsXref is true and builds a list of items (Name, Units, Layer summary).
• Dialog UI: Shows three synchronized list boxes: Xref names, Units, and Layer (read-only display columns).
• Live filter: Filter edit box accepts * and ?, case-insensitive; list updates on every change, plus Filter and Clear buttons.
• Layer summary: Reads layer of Model Space inserts for the Xref name; returns the layer name, Multiple if mixed, or — if none exist.
• Zoom behavior: Selects all Model Space inserts of the chosen Xref, merges their bounding boxes, then calls ActiveX ZoomWindow using LL and UR points (no padding).

Helper functions used

• zx:pair Builds a two-item cons pair (used for returning LL and UR).
• zx:pt3 Builds a 3D point list (x y z).
• zx:nth Safe 0-based index accessor without NTH.
• zx:parse-int Parses digits-only integer strings (used to read list-box index).
• zx:up ASCII uppercase for case-insensitive matching.
• zx:wmatch Wildcard matcher supporting * and ? (case-insensitive).
• zx:unit-str Maps AcInsertUnits enum to readable text (Meters, Feet, Unitless, etc).
• zx:safe-get-units vla-get-Units with error trapping to avoid failures.
• zx:ss-xref-refs ssget of INSERT entities for a block name in Model Space only.
• zx:xref-layer-summary Computes layer display value: single layer, Multiple, or —.
• zx:make-dcl-file Writes a temporary DCL file defining the dialog layout.
• zx:alert-help Help dialog describing filtering, columns, and zoom behavior.
• zx:get-xref-items Builds item triplets (name unit layer) from the drawing Blocks collection.
• zx:filter-items Filters items by wildcard pattern while preserving order.
• zx:ss-bbox Merges bounding boxes across a selection set into one LL and UR pair.
• zx:zoom-ll-ur Pure ActiveX zoom via vla-ZoomWindow (no command calls).
• zx:fill-lists Populates the three list boxes and keeps selection aligned.
• zx:filter-apply Reads filter tile, normalizes empty to *, updates filtered list and refreshes UI.
• zx:apply-zoom Resolves current selection, builds selection set, computes bbox, performs zoom, prints status text.

Functionalities

• Live wildcard filter: Type to filter immediately; supports * and ?; case-insensitive matching.
• Three-column view: Xref Name, Units (from block definition), Layer (from Model Space inserts).
• Synchronized selection: Selecting a row in any list keeps the other two lists aligned to the same index.
• Apply without closing: Apply zooms and leaves the dialog open for repeated zooms.
• Precise bbox zoom: Merges all Model Space inserts into one bounding box and zooms to exact LL and UR corners.
• Robust helpers: Avoids fragile built-ins, traps units errors, and uses a custom wildcard matcher.
• Clean teardown: Unloads dialog and deletes the temporary DCL file after closing.

Result and user-facing output

• If no Xrefs exist: Alerts “No Xrefs found in this drawing.”
• If selection has no Model Space inserts: Prints “No inserts of Xref “NAME” in Model Space.”
• On successful zoom: Prints “Zoomed to Xref: NAME [Units: UNITS | Layer: LAYER]”.
• Startup prompt: Prints guidance to run ZOOMXREF or SELECTXREF for live filtering and zoom.