DXF Viewer plugin 1.5.0.0 for Total Commander
===============================================

 * License:
-----------

Copyright (C) 2026 by Thomas Beutlich

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
https://www.gnu.org/licenses/old-licenses/gpl-2.0.txt


 * Installation:
----------------

Open the plugin archive using Total Commander and installation will start.


 * Description:
---------------

DXF Viewer is a lister plugin (WLX) for Total Commander to display DXF/DWG files
as interactive 2-D views using GDI+.

Supported file formats:
 o DXF (Drawing Exchange Format)
 o DWG (Drawing)

Features:
 o 2-D GDI+ rendering of DXF/DWG geometry
 o TrueType font support for TEXT/MTEXT rendering
 o Mouse interaction: left-drag to pan, wheel to zoom
 o CTRL + left-drag to zoom to selection
 o Right-click context menu for layer visibility control
 o Double-click to fit view
 o Keyboard navigation: arrow keys for panning, +/- for zoom, HOME to reset view
 o Copy to clipboard
 o Dark mode support
 o Background file loading


 * ChangeLog:
-------------

 o Version 1.5.0.0 (21.06.2026)
   - added entity hover highlight: green semi-transparent overlay around hovered entity
   - added handle-based bbox aggregation for HATCH hover highlight (full hull, not just fill line)
   - added click-to-cycle through overlapping entities (left click, like ezdxf Qt viewer)
   - improved LWPOLYLINE hit test: per-segme  nt distance (straight + bulge arc) instead of bbox only
   - added hit test for LWPOLYLINE in block primitives
   - added Aligned (halign=3) text: height and angle now computed from alignment points
   - added Fit (halign=5) text: width scale and angle computed from alignment points
   - added text generation flags (code 71): backward and upside-down mirroring
   - added XCLIP (SPATIAL_FILTER) entity support for block reference clipping (INSERT)
   - changed resize behavior: re-fit drawing to viewport on every resize (like ezdxf Qt viewer)
   - fixed Fit (halign=5) text bounding box to account for width scale
   - fixed ATTDEF rendering: ATTRIB values from INSERT now override the ATTDEF default text
   - fixed ATTDEF standalone display: show TAG instead of default VALUE (raw ATTDEF in modelspace)
   - fixed MINSERT: expand grid (colcount × rowcount) into individual INSERT primitives
   - fixed HATCH spline boundary: evaluate B-spline curves via De Boor's algorithm instead of using raw control points
   - fixed multiple solid HATCH (SOLID pattern) boundaries: outer fill combined with inner holes via GraphicsPath FillMode::Alternate instead of separate overlapping filled polygons
   - fixed MTEXT caret encoding (^c): all DXF caret control codes now decode via chr(c ^ 0x40) matching AutoCAD/ezdxf — ^J = 0x0A (line break), ^I = 0x09 (tab→space since GDI+ can't render control chars), ^[space] = literal caret, ^A..^Z = control chars 1-26, ^a..^z = !..:, etc.
   - fixed MTEXT default width: only apply explicit width (data.widthscale != 1.0) to prevent spurious word-wrap with 1-unit maxWidth
   - fixed TEXT rendering transform order: mirror (textgen) applied in local text space first, then scale (width factor), then rotate — fixes condensed rotated text being sheared
   - fixed TEXT rotation sign: restored correct GDI+ RotateAt direction for clockwise text rotation
   - fixed TEXT width factor (group code 41): now properly populated from DXF data for non-Aligned/Fit text, supporting condensed/expanded text
   - fixed MTEXT word distribution for wide layout rectangles: multi-word content with width much larger than natural text width now distributes words evenly across the full layout rectangle, matching DXF intent for left-aligned MTEXT
   - fixed MTEXT vertical text (flow direction code 72 = 3, Top-to-Bottom): characters stack vertically in columns with proper column advance based on fontSize × 1.25 × lineSpacingFactor
   - fixed Aligned (halign=3) and Fit (halign=5) text position: text baseline now starts at basePoint instead of midpoint, so the rendered text aligns with the reference line as in AutoCAD/ezdxf
   - libdxfrw: added SPATIAL_FILTER object raw data capture
   - libdxfrw: fixed DXF CLASS record parsing to skip malformed records
 o Version 1.4.0.0 (19.06.2026)
   - added MESH (AcDbSubDMesh) entity wireframe rendering
   - added DIMARC entity support
   - added MTEXT paragraph alignment (\pq formatting code)
   - added MTEXT Unicode codepoint escape (\U+XXXX)
   - added MTEXT non-breaking space (\~ renders as U+00A0)
   - fixed ellipse bounding box using minor axis length
   - fixed SPLINE rendering to prefer control points over fit points when both are present
   - fixed MTEXT line spacing to use AutoCAD convention (factor × 5/3 × height)
   - improved MTEXT rendering with paragraph alignment and word-wrapping for width-constrained text
   - libdxfrw: added initial DWG 2013/2018 format support
   - libdxfrw: added TOLERANCE entity read/write support
   - libdxfrw: added proxy graphics decoding for legacy DWG blocks
   - libdxfrw: added MESH (AcDbSubDMesh) decode and polyline face rendering
   - libdxfrw: added AcDbSurface family dispatch for DWG read coverage
   - libdxfrw: added SHAPE entity DWG encode and write API
   - libdxfrw: added HELIX entity DWG read and encode
   - libdxfrw: added OLE2FRAME entity DWG encode (R2000+)
   - libdxfrw: added IMAGE encode with imagedefreactor and display properties
   - libdxfrw: added GROUP entity members emitted as hard pointers
   - libdxfrw: added LEADER block-color, annotation, and direction/offset groups
   - libdxfrw: added LAYOUT object read from OBJECTS section for paper-space tab names
   - libdxfrw: added block-attribute ATTRIBs read/write on INSERT entities
   - libdxfrw: added ATTRIB field-length (code 73) and valign (code 74) read/write
   - libdxfrw: added DICTIONARY, GROUP, SCALE, MLINESTYLE, SUN, WIPEOUTVARIABLES, RASTERVARIABLES, DICTIONARYVAR object readers
   - libdxfrw: added PLOTSETTINGS full field set read/write (shared with LAYOUT prefix)
   - libdxfrw: added DIMSTYLE handle and R2007/R2010 members with dedup
   - libdxfrw: added UCS full DWG parse (origin/axes/elevation/orthoType)
   - libdxfrw: added MINSERT column/row/spacing grid DWG write
   - libdxfrw: added lossless raw-passthrough for unmodeled ENTITIES and OBJECTS
   - libdxfrw: added collision-free handle allocator with $HANDSEED emission
   - libdxfrw: added CLASSES records for unmodeled custom entities and objects
   - libdxfrw: added entity invisibleFlag (code 60) DWG read/write
   - libdxfrw: added entity reactor/xdict handle persistence
   - libdxfrw: fixed MTEXT group-3/1 chunking on codepoint boundaries (DBCS-safe)
   - libdxfrw: fixed POINT xAxisAngle (code 50) degree/radian conversion
   - libdxfrw: fixed LTYPE dash pattern rendering (one style handle per dash)
   - libdxfrw: fixed HATCH boundary spline interpolation and per-loop boundary handles
   - libdxfrw: fixed DWG R2004+ section read buffer model and LZ77 decompression
   - libdxfrw: fixed LZ77 AC18 bit-3 offset extension (opcodes 0x12-0x1F)
   - libdxfrw: fixed DWG IMAGE clip boundary type (code 71) handling
   - libdxfrw: fixed IMAGE/XRECORD truncation hardening and diagnostic logging
   - libdxfrw: fixed DIMENSION rotation guard and R2010 gate
   - libdxfrw: fixed CIRCLE/ARC thickness and extrusion emission in DXF
   - libdxfrw: fixed SORTENTSTABLE handle-stream desync
   - libdxfrw: fixed OLE2FRAME trailing RC byte to prevent handle-stream desync
   - libdxfrw: fixed DXF entity material (347) and plotstyle (390) version gating
   - libdxfrw: fixed CLASSES CRC mismatch as warn-only instead of whole-drawing-fatal
   - libdxfrw: fixed LWPolyline copy/assign to carry vertexnum and reset build pointer
   - libdxfrw: fixed broken pre-2004 entity-chain link no longer fails BLOCKS
   - libdxfrw: fixed LAYOUT viewportCount bounded before reserve (corrupt-input DoS)
   - libdxfrw: fixed handle-wrap assertion via HandleAllocator
   - libdxfrw: fixed DWG codepage mapping for non-Western locales (Cyrillic, Chinese, Japanese, Korean)
   - libdxfrw: fixed LAYOUT viewport_count bit-length decoding for AC1018+ files
   - libdxfrw: fixed MLINESTYLE per-element linetype index version gate for R2000–R2013 files
   - libdxfrw: fixed raw-net numeric-group capture corruption on DXF read
   - libdxfrw: fixed raw-net binary-chunk capture and reactor owner mis-latch on DXF read
   - libdxfrw: fixed POLYLINE_MESH smooth M/N subdivision density discarded on DWG read
   - libdxfrw: fixed DimOrdinate coordinate-type flag bit alignment (X/Y ordinate type)
   - libdxfrw: fixed ATTRIB/ATTDEF lockPosition read version gate (R2007+)
   - libdxfrw: fixed DWG header key names for DIMADEC/DIMFRAC
   - libdxfrw: fixed IMAGEDEF pixel dimensions discarded on DWG read
   - libdxfrw: improved DWG file parsing robustness (CRC validation, buffer bounds, truncation checks)
 o Version 1.3.0.0 (14.06.2026)
   - added status bar toggle (press B) with zoom, viewport and entity information
   - added IMAGE/IMAGEDEF entity support (raster image references)
   - fixed HATCH boundary collection for lines, circles, polylines, and arcs
   - fixed ACAD_TABLE entity rendering
   - improved MTEXT rendering with GDI+ word-wrapping for width-constrained text
   - libdxfrw: added ACAD_TABLE entity dispatch
   - libdxfrw: fixed MTEXT Embedded Object (code 101) handling
   - libdxfrw: fixed HATCH arc complementary angle conversion for CW arcs
   - libdxfrw: fixed HATCH DWG pattern line angle/offset to use world-frame convention
 o Version 1.2.1.0 (03.06.2026)
   - fixed: optimize rendering performance
   - fixed HATCH pattern lines
   - libdxfrw: fixed reading pattern lines from DWG file
 o Version 1.2.0.0 (01.06.2026)
   - added TrueType font support using XDATA font family names
   - fixed ByBlock and ByLayer color inheritance for entities on layer "0" in blocks
   - fixed: optimize rendering performance
   - fixed MLINE justification (offset positioning for Top/Bottom styles)
   - fixed 3D projection for circles, arcs, ellipses, 3DFACE, LWPolyline
   - fixed: keep center point invariant on +/- zoom
   - improved line type rendering with global LTSCALE, dot support, and custom patterns
   - libdxfrw: added ATTDEF, 3DSOLID entity dispatch and ACDSDATA section parsing
   - libdxfrw: fixed HELIX entity parsing to capture entity-level properties
   - libdxfrw: fixed parsing HATCH pattern definition lines
   - libdxfrw: improved load performance
 o Version 1.1.0.0 (27.05.2026)
   - added right-click context menu for layer visibility toggle
   - added zoom-to-selection via Ctrl+Left-drag
   - added layer visibility filtering for block (INSERT) entities
   - added auto-discovery of layers not defined in the LAYER table
   - fixed layer "0" entities in blocks to correctly inherit INSERT layer
   - fixed arrow key navigation direction
   - libdxfrw: fixed DIMENSION block name resolution with offset-based handles
   - libdxfrw: fixed Dynamic Block name resolution for INSERT entities
   - libdxfrw: fixed entity visible property from invisible flag
   - libdxfrw: fixed out-of-bounds access and buffer checks
 o Version 1.0.2.0 (25.05.2026)
   - added support for MLINE/XLINE
   - fixed Unicode path issue
   - fixed: do not reset zoom on resize
   - improved HATCH support
   - improved heuristic on initial zoom scale
   - rebuilt with patched libdxfrw from LibreCAD
   - libdxfrw: added wide-string file path support
   - libdxfrw: fixed DWG codepage mapping for non-Western encodings
 o Version 1.0.1.1 (22.05.2026)
   - rebuilt with patched libdxfrw
 o Version 1.0.1.0 (21.05.2026)
   - added DWG (Drawing) file format support
   - added font family matching for text rendering
   - added true color (24-bit) support for entities and layers
   - added solid fill rendering for HATCH
   - fixed line weight rendering
   - fixed MTEXT formatting codes leaking into displayed text
   - fixed arc direction rendering
   - fixed text width estimation for multi-byte (CJK) characters
   - libdxfrw: fixed text encoding corruption when viewing multiple DWG files
 o Version 1.0.0.1 (19.05.2026)
   - first public version
   - built with libdxfrw, win-iconv


 * References:
--------------

 o libdxfrw: C++ library to read and write DXF/DWG files
   - https://github.com/LibreCAD/LibreCAD/commits/master/libraries/libdxfrw
 o win-iconv: Lightweight iconv implementation for Windows
   - https://github.com/win-iconv/win-iconv
 o WLX Writer's Reference by Christian Ghisler
   - https://ghisler.github.io/WLX-SDK


 * Trademark and Copyright Statements:
--------------------------------------

 o Total Commander is Copyright (C) 1993-2026 by Christian Ghisler, Ghisler Software GmbH.
   - https://www.ghisler.com


 * Feedback:
------------

If you have problems, questions, suggestions please contact Thomas Beutlich.
 o Email: support@tbeu.de
 o URL: http://tbeu.totalcmd.net