2026-06-21  Antigravity <antigravity@google.com>

	* Version 3.9.2
	- Feature: Completed Second Generation Eurocode 2 (EN 1992-1-1:2023) Concrete Member Verification:
	  * Shear capacity without shear reinforcement ($V_{Rdc}$) based on Critical Shear Crack Theory (CSCT) using roughness/aggregate-size parameter $d_{dg}$ and minimum stress capacity limit $\tau_{Rdc,min}$.
	  * Punching shear capacity at $0.5d$ perimeter with $k_{pb}$ gradient enhancement factor.
	  * SLS crack width spacing and strain difference calculations updated to 2nd Gen factors ($k_b = 0.8$, $k_{fl} = 0.5$, $k_w = 1.3$).
	  * Dynamic column slenderness limit criteria ($\lambda_{lim}$) for second-order analysis using calculated creep ($A$), mechanical reinforcement ratio ($B$), and moment diagram curvature ratio ($C$) parameters.
	- Feature: Completed Second Generation Eurocode 3 (EN 1993-1-1:2022) Steel Stability:
	  * Implemented elasto-plastic section classification and elasto-plastic section modulus ($W_{ep}$) interpolation for Class 3 webs and Class 3 circular hollow sections (CHS).
	  * Updated shear buckling limit parameter $\eta$ for high-strength steel grades.
	- Compatibility: Maintained strict Tcl/Tk 8.0 compatibility.

2026-06-20  Antigravity <antigravity@google.com>

	* Version 3.9.1
	- Feature: Implemented Second Generation Eurocode 0 (prEN 1990:2020) load combination equations (Eq 8.12, 8.12a/b) and Consequence Class (K_FI = 0.9, 1.0, 1.1) safety factor scaling.
	- Fix: Resolved Tcl/Tk 8.0 compatibility bug in ecconcrete.tcl (avoiding unsupported canvas text -angle parameter on older Tk versions).
	- Fix: Prevented integer division in seismic.tcl CQC modal combination calculations.
	- Compatibility: Observed strict Tcl/Tk 8.0 compatibility.

2026-06-20  Antigravity <antigravity@google.com>

	* Version 3.9.0
	- Feature: Added Eurocode 5 (EN 1995-1-1 Section 8) bolted wood-to-steel plate connection design verification using Johansen's yield theory.
	- Feature: Upgraded DXF import module to support 3D coordinates parsing and added a slice projection selection dialog with 3D isometric wireframe previews.
	- Fix: Resolved optionMenu widget `.get` call crashes and braced variable scope errors in connection dialog.
	- Compatibility: Maintained strict Tcl/Tk 8.0 compatibility across all modified modules.

2026-06-19  jirka <jirka@sdf.org>

  * Version 3.8.0
  - Feature: more logical View and Toggle Menus
  - Feature: toggle for filled diagrams is saved in config
 
2026-06-19  Antigravity <antigravity@google.com>
 
	* Version 3.7.12
	- Fix: Resolved Tcl/Tk 8.0 compatibility issues in modular template engine (`pow` function type-coercion bypass) and robust startup sourcing (`catch` loop wrapper with logging).
	- Compatibility: Observed strict Tcl/Tk 8.0 compatibility.

2026-06-19  Antigravity <antigravity@google.com>
 
	* Version 3.7.11
	- Feature: Added materials_ec_2nd.tcl with database lookup support for Second Generation Eurocode concrete/steel properties, thickness-dependent yield limits up to S700, and safety factors.
	- Compatibility: Observed strict Tcl/Tk 8.0 compatibility.

2026-06-19  Antigravity <antigravity@google.com>
 
	* Version 3.7.10
	- Feature: Added a hidden menu block for Second Generation Eurocodes in the Design menu, controlled by show_second_gen_preview flag, ready for future verification module implementations.
	- Compatibility: Observed strict Tcl/Tk 8.0 compatibility.

2026-06-19  Antigravity <antigravity@google.com>
 
	* Version 3.7.9
	- Feature: Added dynamic HTML (.html) report export support under the new Reports menu, generating styled, standalone interactive documents without external libraries.
	- Docs: Updated TODO.md roadmap to mark the "shaded forces diagrams" bug as resolved.
	- Compatibility: Observed strict Tcl/Tk 8.0 compatibility.

2026-06-19  Antigravity <antigravity@google.com>
 
	* Version 3.7.8
	- UI: Replaced numeric indices in the side panel's analysis headers (e.g. "Analysis 2") with descriptive names (e.g. "Static", "Stability", "P-Delta", "LargeDef", "Dynamic", "Seismic", "Plasticity").
	- Compatibility: Observed strict Tcl/Tk 8.0 compatibility.

2026-06-19  Antigravity <antigravity@google.com>
 
	* Version 3.7.7
	- Feature: Divided the File -> Export menu into two menus: Export (retains existing exports to FEA/CAD software) and Reports (for image files, LaTeX, Markdown, and CSV).
	- Compatibility: Observed strict Tcl/Tk 8.0 compatibility.

2026-06-18  jirka <jirka@sdf.org>
 
	* Version 3.7.6
	- Fix: shaded forces diagrams in Tcl/Tk 8.0


2026-06-18  jirka <jirka@sdf.org>
 
	* Version 3.7.5
	- Fix: Resolved Tcl/Tk 8.0 compatibility bugs where coordinate lists passed to canvas creation commands resulted in option-parsing crashes ("bad screen distance -tags") or argument count mismatches. Utilized robust `eval [list ...] $coords [list ...]` list-concatenation to safely expand coordinate lists.
	- Fix: Resolved identical canvas list-passing and option-parsing crashes in the moment symbol, deformations, mode shapes, and result diagram plotting in both `fem1.tcl` and `ram.tcl`.
	- Fix: Resolved a Tcl/Tk 8.0 compatibility bug where passing negative values (such as `-1`) to `switch` commands caused option-parsing errors ("bad option -1"). Added `--` option-terminators to all relevant `switch` commands.
	- Fix: Resolved a Tcl/Tk 8.0 compatibility bug in Markdown export where Report::generate_full was invoked without a leading double-colon prefix, causing an "invalid command name" runtime error in Wish 8.0. Fully qualified the call to ::Report::generate_full.

	* Version 3.7.4
	- Feature: Enhanced the Engineering Optimization module to support weight-based optimization (sorting candidates by cross-sectional Area A instead of moment of inertia Iy).
	- Feature: Implemented Group-Aware Optimization to ensure all elements in the same structural member group (e.g. continuous beam/column stack) retain section uniformity.
	- Feature: Added User-Adjustable target utilization limits (sweet-spot configuration).
	- UI: Replaced direct optimization commands in the menus and selection dialogs with an interactive "Engineering Optimization Settings" configuration window.

	* Version 3.7.3
	- Feature: Category selections in the load case manager now display full names (such as "Gravitation (G)") instead of single letters, mapped dynamically to preserve Eurocode combination and solver compatibility.
	- Feature: Implemented "Copy..." load case function inside the Load Case Manager to duplicate loads, displacements, and metadata.

	* Version 3.7.2
	- Feature: Implemented maximum relative deflection (chord-deviation) checks using Hermite interpolation for ULS/SLS design in EC3 (steel), EC5 (timber), and EC2 (concrete).
	- Fix: Resolved canvas selection mode locking by preventing editing_mode activation.
	- Fix: Fixed "expected number but got" file-opening crash by sanitizing empty values in read_data.
	- Fix: Fixed force/deformation diagram misalignment after zooming by preserving the viewport scale and offset in get_max_def.
	- Fix: Sanitized toolbar load case and mode shape inputs to prevent invalid string/non-numeric characters.

 
	* Version 3.7.1
	- Feature: Toolbar cleaning (Paint moved to Edit menu)
	- Fix: Editing mode fixed

2026-06-17  Gemini CLI <gemini-cli@google.com>

	* Version 3.7.0
	- Feature: EN 1993-1-8 Steel Connections (Bolted Shear/Moment). Added interactive connection design dialog (right-click node), canvas visualization, and detailed Eurocode 3 joint verification (Bolt shear, bearing, tension, and interaction).
	- Feature: EN 1995-1-2 Timber Fire Design. Implemented the Reduced Cross-Section Method using standard charring rates and zero-strength layer calculations.
	- Feature: "Match Properties" Paintbrush tool added to the toolbar for rapid element property copying.
	- Feature: "Highlight Model Errors" visualizer (View menu) to flag floating nodes, duplicate elements, and invalid properties.
	- Performance: Systematic Tcl Bytecode Optimization pass (braced all high-frequency `expr` calls) for Tcl 8.0 speedups.
	- Fix: Resolved critical file format regression and type-mismatch bugs that caused loads/supports to be hidden in certain models (e.g., panelak3.df).
	- Fix: Ensured UI synchronization of active Load Case immediately upon file opening.
	- Fix: Corrected missing global variables causing crashes in element property matching.

2026-06-17  Gemini CLI <gemini-cli@google.com>

	* Version 3.6.0
	- Feature: EN 1993-1-2 Fire Design for Steel members. Implemented time-based thermal analysis using the standard ISO 834 fire curve, calculation of critical steel temperatures, and dynamic application of temperature-dependent yield/stiffness reduction factors ($k_{y,\theta}$, $k_{E,\theta}$) during EC3 verification.
	- Feature: Model Healer expanded with "Auto-Constraint" (snapping unconnected or near-miss nodes to element axes) and "Delete Duplicate Elements" tools.
	- Fix: Restored the elastic red rubber-band line during element creation by correcting 'editing_mode' side panel logic.
	- Fix: Resolved Tcl 8.0 compatibility regressions in the Modular Report Engine (`regsub` variable handling) and SAF Export plugin (`regexp -start` switch removed).

2026-06-16  Antigravity <antigravity@google.com>

	* Version 3.5.0
	- Feature: Member Bow Imperfections ($e_0$) tool (Edit menu) for automated EC3-compliant equivalent transverse loads.
	- Feature: Shaded Internal Force Diagrams (View menu toggle) providing professional shaded-polygon visualizations for bending and shear.
	- Feature: Seismic Spectrum Visualizer in the Seismic Settings dialog, providing real-time interactive plotting of the Eurocode 8 spectrum.
	- Infrastructure: Modular Report Template Engine ('reports.tcl') for structured, format-agnostic engineering documentation.
	- Refactor: Markdown and LaTeX exports now utilize the modular block template system for consistent presentation.
	- Fix: Resolved crash in Markdown export by centralizing total mass calculation in the Report Engine.
	- Fix: Ensured early initialization of result-type variables to prevent UI errors in fresh models.

2026-06-16  Antigravity <antigravity@google.com>

	* Version 3.4.1
	- Feature: Global Geometric Sway Imperfections tool (Edit menu) for automated EC3-compliant tilting ($\phi$) of frames.
	- Tests: Comprehensive complex frame regression test suite ('tests/test_complex_frame.tcl') for multi-storey frame verification.
	- Tests: Added mathematical verification test for sway imperfections ('tests/test_imperfections.tcl').
	- Fix: Corrected source path in 'tests/init.tcl'.
	- Fix: Refined UI mocks for robust headless non-linear analysis verification.

2026-06-16  Antigravity <antigravity@google.com>

	* Version 3.4.0
	- Feature: Advanced Seismic Analysis implementing Eurocode 8 Response Spectrum (Type 1 and 2).
	- Feature: CQC (Complete Quadratic Combination) modal superposition for high-accuracy seismic response.
	- Feature: Advanced Plastic Analysis with quadratic N-M interaction surface and P-Delta stability integration.
	- Fix: Robust SAF export/import compatibility (numeric values in export, improved XML parsing, and smart header detection in import).
	- Fix: Resolved several crashes in Large Deformation and P-Delta analyses related to ID mapping, expression bracing, and scope resolution.
	- Documentation: Updated USER_GUIDE.md and THEORY_MANUAL.md with technical details and usage guides for new analysis modules.

2026-06-15  Antigravity <antigravity@google.com>

	* Version 3.3.1
	- UI: Fixed Bulk Element Change in side panel by adding missing "Apply" button and ensuring selection persistence when using library dialogs.
	- UI: Added "Cancel" buttons to all side panel editing views (Node, Element, Support, Force, Load) to allow discarding changes.
	- UI: Renamed "Apply to Selection" back to "Apply" for consistency.
	- UI: Fixed a bug where the subgrade reaction field (kw) appeared empty; it now defaults to 0.0 correctly.
	- Fix: Added descriptive validation error messages (e.g., "Young modulus must be positive!") to prevent "silent" button failure.
	- Fix: Resolved crash `can't read "m_sel_rect": no such variable` by initializing selection variables at global scope and adding safety checks in 'selection_end'.
	- Fix: Ensured cot(theta) and kw properties are correctly preserved and applied during bulk changes.

2026-06-15  Antigravity <antigravity@google.com>

	* Version 3.3.0
	- Feature: Implemented exact Soil-Structure Interaction (SSI) via Winkler Foundation continuous elastic bedding. The subgrade reaction modulus ($k_w$) is analytically integrated into the element stiffness matrix using full 6x6 Hermite shape functions.
	- Feature: Expanded the material library with common Geotechnical materials (Soft/Stiff Clay, Loose/Dense Sand, Gravel) to support soil-structure interaction modeling.
	- UI: Added a "Soil" filter category to the material library selection dialog.
	- Feature: Implemented lateral wind load resistance for Masonry (EC6), including flexural strength verification ($f_{xk1}$) with the beneficial effect of vertical compressive stress.
	- Feature: Expanded the material library with standard Masonry grades (5MPa, 10MPa, 15MPa).
	- UI: Added a material filter (Steel, Concrete, Timber, Masonry, Other) to the material library selection dialog for better usability.
	- Feature: Implemented local bearing checks for Timber (EC5) compression perpendicular to grain and Masonry (EC6) concentrated load checks using standard default geometric parameters.
	- Feature: Implemented refined vertical load resistance for Masonry (EC6) using the Annex G method for second-order effects.
	- Feature: Integrated EN 1995-1-1 Lateral-Torsional Buckling (LTB) verification ($k_{crit}$) for Timber (EC5) design, including updated combined bending and compression interaction checks.

2026-06-14  Antigravity <antigravity@google.com>

	* Version 3.2.0
	- Feature: Integrated EN 1993-1-5 web shear buckling verification check for I, U, and Box sections in Steel (EC3) design.
	- Feature: Integrated EN 1993-1-1 Section 6.2.7 Saint-Venant torsion and combined torsion/bending verifications for Steel (EC3) design.
	- Fix: Updated SAF Export plugin 'plugins/export_saf.tcl' to export the actual out-of-plane cross-sectional properties (Iz, It, Iw) of the designed sections instead of dummy hardcoded placeholders, falling back to safe default values when undefined.
	- Tests: Added unit test suite in 'tests/test_ec3_new_checks.tcl' to verify the new shear buckling and torsion checks.
	- Tests: Added unit test suite in 'tests/test_export_saf.tcl' to verify that cross-sectional properties are correctly exported to SAF.
	- Tests: Added unit tests 'tests/test_timber_c90_headless.tcl' and 'tests/test_masonry_conc_headless.tcl' to verify local bearing checks.
	- Tests: Added unit test 'tests/test_masonry_wind_headless.tcl' to verify lateral wind load resistance in Masonry.

2026-06-14  Antigravity <antigravity@google.com>

	* Version 3.1.0
	- Feature: Implemented "Engineering Optimization" module. Iteratively resizes structural elements based on their active Eurocode utilization ratios, downsizing sections if utilization is under 80% or upsizing if over 99% (using moment of inertia Iy as the size metric).
	- Feature: Made the Engineering Optimization module selection-aware, optimizing only the selected elements if a selection is active, or all elements if nothing is selected.
	- UI: Added "Engineering Optimization" option to the Design menu. Repositioned the EC6 Masonry Show Utilization option for consistency.
	- UI: Enabled the Selection Info popup window when "Select All" is triggered, allowing for bulk operations on the entire model's selection.
	- UI: Added an "Optimize Selected" button to the Selection Info popup dialog when elements are selected.
	- Tests: Added comprehensive unit test suite in 'tests/test_engineering_optimization.tcl' to verify downsizing, upsizing, sweet-spot, and selection-aware optimization behaviors.
	- Tests: Added unit test in 'tests/test_select_all.tcl' to verify the Selection Info window triggers properly on "Select All".

2026-06-14  Antigravity <antigravity@google.com>

	* Version 3.0.1
	- Fix: Resolved Tcl/Tk 8.0 compatibility issues by removing unsupported '-padx' and '-pady' options from the 'frame' widget constructor in 'fem1.tcl', 'influence.tcl', and 'sections.tcl'. Applied the equivalent padding via the 'pack' geometry manager or child widgets instead.
	- Fix: Wrapped the 'mult_cached_m' call in 'solver.tcl' inside a 'catch' block to prevent runtime crashes if the C matrix cache has already been freed, gracefully falling back to non-cached calculations.

2026-06-14  Gemini CLI <gemini-cli@google.com>

	- Feature: Created project website in 'www' directory with English (index.html) and Czech (index_cz.html) versions.
	- Documentation: Expanded and converted manuals to web-native formats (user_guide.html, theory_manual.html).
	- Distribution: Assembled complete program package (fem1.tar.gz) including scripts, C accelerator, manuals, and examples.
	- UI: Removed "Indigo Magic" references from web presence.

2026-06-13  Antigravity <antigravity@google.com>

	* Version 3.0.0
	- Feature: Massive performance optimization for all structural analyses via a completely rewritten C Solver Accelerator (ANSI 89 C).
	- Optimization: Implemented a Stateful C Matrix Cache that performs matrix factorizations (LU decomposition) once per analysis instead of once per iteration.
	- Performance: Achieving up to 40x speedup in static analysis and over 10,000x speedup in stability and dynamics iteration loops for medium-sized models.
	- Portability: Added multi-threading support via pthreads with a runtime-tunable thread count (FEM_THREADS env var) and automatic serial fallback.
	- Fix: Resolved GUI hangs in dynamics analysis for small models by optimizing Tcl-C data exchange using direct Tcl_Obj list access and scoping flexibility.
	- Compatibility: Verified strict adherence to ANSI 89 C and Tcl/Tk 8.0 standards for legacy systems (e.g., SGI IRIX).

2026-06-13  Antigravity <antigravity@google.com>

	* Version 2.6.3
	- Feature: Implemented detailed design reports for steel (EC3), concrete (EC2), timber (EC5), and masonry (EC6) in Markdown, CSV, and LaTeX formats.
	- Fix: Added missing e_mat and e_sec declarations to global lists in export_csv, export_latex, and export_latex_full procedures.
	- Tests: Added comprehensive automated test suite `tests/test_design_reports.tcl` to verify format correctness and contents of design reports.

2026-06-13  Antigravity <antigravity@google.com>

	* Version 2.6.2
	- Feature: Added material-based filtering (Steel, Concrete, Timber, Masonry) to the cross-section library selection dialog.
	- Library: Added standard masonry section sizes (`Masonry 100`, `Masonry 150`, `Masonry 200`, `Masonry 300`) to the cross-section library.
	- Fix: Resolved issue where side panel model statistics did not update after opening, saving, or starting a new file.
	- Fix: Fixed a Tcl 8.0 compatibility bug where global declarations contained fully qualified variable names (e.g., `global ::sec_filter`), which caused a runtime crash when opening the section library.

2026-06-13  Antigravity <antigravity@google.com>

	* Version 2.6.1
	- Fix: Replaced `string is double` with `catch {expr {double($val)}}` in `fem1.tcl` for Tcl 8.0 compatibility.
	- Fix: Conditionalized canvas line `-dash` option based on Tk version in `ecconcrete.tcl`, `influence.tcl`, and `plugins/export_saf.tcl` to support Tk 8.0 where the option is not available.

2026-06-12  Antigravity <antigravity@google.com>

	* Version 2.6.0
	- Feature: Integrated circular concrete column support (`ConcD` sections) into EC2 design checks. This includes a circular segment N-M interaction calculation, slenderness checks, SLS crack width calculations on equivalent rectangular sections, and N-M diagram plotting.
	- Library: Added standard circular concrete profiles (`ConcD 300`, `ConcD 400`, `ConcD 500`) to the cross-section library.
	- Feature: Implemented automatic detection and grouping of continuous collinear members (supermembers) to calculate stability system lengths ($L_{sys}$) automatically.
	- Feature: Implemented EN 1990 Table A1.1 load action ψ factor lookup helper dialog and 12 new variable action subcategories.
	- UI: Added "Auto-group Continuous Members" menu option to Edit Menu.
	- UI: Added "ψ Lookup..." button next to Category option menus in "Add Load Case" and "Edit Load Case" dialogs.
	- Tests: Added unit and integration test coverage for all features, including circular column verification.
	- Fix: Corrected a Tcl list evaluation bug (`e_group` vs `$e_group`) in the select group elements loop.

2026-06-12  Antigravity <antigravity@google.com>

	* Version 2.3.0
	- Feature: Enabled SAF (Structural Analysis Format) Import plugin.
	- UI: Added a real-time interactive 3D isometric preview canvas to the SAF Import cut selection dialog, showing the entire wireframe model, the active cutting plane, and color-coded selection highlights.
	- Healer: Added "Delete Unconnected Nodes" functionality to Model Healer to automatically clean up floating nodes and their associated supports, forces, and dimension lines. Added automated test suite for the feature.
	- Healer: Added "Divide Elements by Unconnected Nodes" functionality to Model Healer to automatically split elements at intermediate unconnected nodes. Updated tests.
	- UI: Added interactive hover tooltips for nodes (showing ID, coordinates, displacements, reactions) and elements (showing ID, section, material, forces, and utilization). Added tests.
	- UI: Added an "Interactive Tooltips" checkbutton in the Toggle Menu to turn tooltips on/off, with automatic tooltip clearing.
	- Config: Added `show_tooltips` to configuration file serialization to persist user preferences.
	- EC5: Integrated Serviceability Limit State (SLS) Creep Deformation verification ($k_{def}$) based on EN 1995-1-1 Table 3.2.
	- UI: Updated the EC5 settings dialog to allow selecting Service Class 1, 2, or 3 individually, displaying the calculated $k_{def}$ factor dynamically. Added tests.

2026-06-11  Gemini CLI <gemini-cli@google.com>

	* Version 2.1.0
	- Feature: Advanced EN 1990 Load Combinations (ULS Eq 6.10a/b, SLS Frequent and Quasi-permanent).
	- Feature: Formal EC2 Crack Width Verification (EN 1992-1-1, 7.3.4) with long-term effects.
	- Feature: EC2 Second-Order Effects for slender columns (Nominal Stiffness Method).
	- Feature: Expanded Steel Profile Database (added UPN, SHS, and CHS profiles).
	- Feature: Enhanced EC3 Section Classification with exact geometric inference (web/flange checks).
	- UI: Interactive high-resolution N/M interaction diagram with numerical axes and labels.
	- Documentation: Comprehensive update of User Guide and Theory Manual with EC implementation details.
	- Fix: Resolved UI geometry manager conflict in element side panel.

2026-06-10  Gemini CLI <gemini-cli@google.com>

	* Version 2.0.3
	- Compatibility: Fixed Tcl 8.0 regressions (replaced 'lset' with 'lreplace', removed 'string match -nocase').

	* Version 2.0.2
	- Feature: Interactive Filtering (View -> Interactive Filtering...) to isolate specific materials or highly utilized members (> threshold).
	- Feature: Improved LaTeX Export with a professional template (Table of Contents, Booktabs, Colored Status).
	- Feature: Added 'Default Element Properties' to Create menu for easier member templating.
	- Feature: Implemented Member Group Visualization with color-coding and legend.
	- Feature: Configurable Seismic Analysis (added settings dialog and direction selection).
	- UI: Fixed unresponsiveness of materials dialog by improving modal grab logic.
	- UI: Fixed visual distortion (self-intersecting polygons) when plotting Influence Lines that cross the zero-axis.
	- UI: Polished Influence Line window to match main canvas colors, added Export buttons (EPS/Text), and added visual track of elements and nodes.
	- UI: Updated SGI/IRIX native color scheme to include classic dusty pink input fields (can be tested on any OS via FORCE_IRIX=1 environment variable).
	- UI: Refactored all modal dialogs to use safe 'update idletasks' + 'winfo viewable' pattern.
	- Fix: Prevented crash in EC verification when internal forces are missing (added safety checks).

2026-06-10  jirka <jirka@sdf.org>

        * Version 2.0.0
        - Feature: Seismic Analysis (SRSS modal combination, basic response spectrum).
        - Feature: Plastic Hinge Analysis (Incremental collapse mechanism for frames).
        - Feature: Influence Lines for moving loads and sensitivity analysis.
        - UI: Major overhaul of Eurocode Design GUIs (Interactive plots, real-time updates).
        - Infrastructure: Refactored TODO into a comprehensive project roadmap.

2026-06-08  jirka <jirka@sdf.org>

	* Version 1.9.9
	- Fix: IRIX font and look

2026-06-08  jirka <jirka@sdf.org>

	* Version 1.9.8
	- Feature: SAF (Structural Analysis Format) Export plugin.
	- Feature: Native XLSX generation via XML-ZIP pattern (Tcl 8.0 compatible).
	- Feature: Mapped 2D LittleDef models to 3D SAF standard (Z=0 plane).
	- Architecture: Moved SAF logic to 'plugins/export_saf.tcl' to maintain modularity.

2026-06-08  jirka <jirka@sdf.org>

	* Version 1.9.7
	- Feature: EC2: Integrated Creep Effects ($\phi_{ef}$) into Reinforced Concrete verification.
	- Feature: EC2: Added long-term deflection estimation and utilization checks.
	- Fix: Resolved GUI freeze bug during element selection/editing.
	- UI: Implemented secure modal grab pattern to prevent hangs in 'tkwait visibility'.
	- UI: Ensured 'activesel' state is reset on dialog destruction to prevent modal deadlocks.
	- Documentation: Updated User Guide and Programmer Manual with version 1.9.7 details.

2026-06-07  jirka <jirka@sdf.org>

	* Version 1.9.6
	- IRIX: Implemented Desktop Integration (Phase 2) via File Typing Rules (littledef.ftr).
	- IRIX: Added support for Drag-and-Drop, custom icons, and Alt-Double-Click solve mode.
	- Audit: Completed full codebase audit for Tcl/Tk 8.0 incompatibilities.
	- Fix: Verified and fixed potential regressions in list handling for legacy systems.
	- Documentation: Added IRIX icon compilation guide to Programmer Manual.

2026-06-07  jirka <jirka@sdf.org>

	* Version 1.9.5
	- UI: Added native IRIX (Indigo Magic) look and feel detection and integration.
	- UI: Implementation of SGI Motif color palette and font standards for IRIX platforms.
	- Performance: Repo-wide optimization of Tcl math operations using braced expressions.
	- Performance: Enabled Bytecode Compilation for critical loops in Tcl/Tk 8.0, yielding significant speedups.
	- Documentation: Updated User Guide and Programmer Manual with IRIX and performance details.

2026-06-07  jirka <jirka@sdf.org>

	* Version 1.9.4
	- Fix: Resolved matrix fill-in persistence bug in iterative stability and dynamics solvers.
	- Fix: Corrected axial force sign convention in detailed reports and exports to be consistently tension-positive.

2026-06-06  jirka <jirka@sdf.org>

	* Version 1.9.3
	- UI: Added double-click binding to canvas to trigger "Fit View" function.
	- Documentation: Updated User Guide and Manual with new interaction tips.

2026-06-06  jirka <jirka@sdf.org>

	* Version 1.9.2
	- Feature: Added Portal Frame (Pitched Roof) Wizard for industrial structures.
	- Feature: Added Continuous Beam Wizard with automated pinned/roller support placement.
	- Feature: Added Vierendeel Girder Wizard for rigid-jointed architectural frames.
	- Feature: Implemented "Auto-Connect" logic in all wizards. Selecting a node before running a wizard now seamlessly integrates the new structure using the existing node ID.
	- Refactor: Introduced add_element_internal helper in Wizard namespace to centralize element generation logic.
	- Tcl/Tk 8.0 compatibility strictly maintained across all new structural templates.

2026-06-06  jirka <jirka@sdf.org>

	* Version 1.9.1
	- Refactor: Moved EC2, Indet, and Wizard modules into Tcl 8.0 namespaces to prevent global scope pollution.
	- UI: Added keyboard shortcuts for modeling modes: N (Node), E (Element), U (Support).
	- UI: Enhanced Escape key to reset application to "Ready" state (clears selection and exits active mode).
	- UI: Updated "Create" menu with discoverable accelerator labels for shortcuts.
	- Fix: Corrected axial force sign convention in solver.tcl (critical for P-Delta and stability).
	- Fix: Resolved sparse matrix access errors ("no such element in array") in Tcl solver fallback.
	- Fix: Improved Large Deformation solver stability through geometry synchronization and internal force fixes.
	- Fix: Restored compilability and global scoping in ANSI89 C solver extension (fem_c_solver.c).
	- Testing: Added automated performance benchmark and analytical P-Delta verification tests.
	- Documentation: Added explicit C accelerator compilation guide to PROGRAMMER.md.

2026-06-05  jirka <jirka@sdf.org>

	* Version 1.9.0
	- Performance: Transitioned to Sparse Matrix representation (only non-zero entries stored).
	- Performance: Implementation of ID mapping for O(1) lookups of nodes/elements.
	- Performance: Added optional ANSI89 C accelerator for heavy math loops (up to 5x+ speedup).
	- Fix: Stability and Dynamics solvers updated for sparse matrix compatibility.
	- Tcl/Tk 8.0 compatibility strictly maintained.

2026-06-05  jirka <jirka@sdf.org>

	* Version 1.8.0
	- Performance: Major solver optimization. Transitioned core global matrices (K, M_global, Kg_global) from 1D Tcl lists to 2D Tcl arrays.
	- Performance: Gauss elimination and assembly operations now have O(1) memory access, restoring O(N^3) solver complexity and eliminating list copy-on-write overhead.

2026-05-31  jirka <jirka@sdf.org>

	* Version 1.7.8
	- Feature: Improved Utilization UI (numerical U-ratio labels on canvas)
	- Feature: Added "Clear Design Results" to Design menu
	- Feature: Automated design verification tables in Markdown/LaTeX reports
	- Refactor: EC modules now auto-activate utilization display upon run

2026-05-31  jirka <jirka@sdf.org>

	* Version 1.7.7
	- Feature: Implemented Member Groups to treat continuous elements as a single design member
	- EC3: Integrated Member Groups system length (L_sys) into flexural and LTB buckling calculations
	- EC3: Implemented Method 2 (Annex B) stability interaction factors (k_yy, k_zy)
	- EC3: Refined Section Classification (EN 1993-1-1 Table 5.2) based on actual stress gradients
	- EC6: Implemented Annex G slenderness reduction factor (Phi) using Member Groups length
	- EC6: Refined shear resistance calculation considering vertical compressive stress

2026-05-31  jirka <jirka@sdf.org>

	* Version 1.7.6
	- Feature: Implemented Headless Solver & Reporting CLI
	- CLI: Added --solve flag to process all load cases without opening GUI
	- CLI: Added --report <type> <file> flag for automated report generation
	- Refactor: Decoupled exts.tcl reporting engine from GUI-specific Tk commands
	- Fix: Prevented solver.tcl from parsing global argv when sourced as a library
	- Feature: Added optional filename argument to all export_* procedures

2026-05-31  jirka <jirka@sdf.org>
	- Feature: Added Gravitation Load Generator in Edit menu
	- Feature: Automatic self-weight calculation based on material density and section area
	- Consolidation: Standardized application to use solver.tcl as the sole solver
	- UI: Fixed File-New dialog to always show positive dimensions
	- UI: Set safe defaults for new workspace (Width: 8, Height: 6)
	- UI: Select All now automatically enters selection mode
	- Bug: Axial element loads were interpreted with reversed signs and incorrect values
	- Fix: Corrected axial load assembly and synchronized with physical diagram convention
	- Bug: Internal force diagrams were missing or invisible for models with zero nodal displacements
	- Fix: Ensured multipliers are calculated for all cases and balanced N, V, M scaling
	- Bug: Ideal hinges had non-zero moments due to equilibrium sign error and numerical noise
	- Fix: Corrected shear-moment equilibrium formula and added explicit zeroing at hinges
	- Documentation: Updated USER_GUIDE and manual with new feature details


2026-05-25  jirka <jirka@sdf.org>

	* Version 1.7.4
	- Bug: Ideal and semi-rigid hinges were too stiff under element loads
	- Fix: Implemented generalized equivalent nodal load (Fe) adjustment for hinges
	- Fix: Verified Fe adjustment for point loads, distributed loads, and temperature
	- Compatibility: Synchronized Fe adjustment logic across all solver files
	- Compatibility: Updated read_df_data to robustly handle ka/kb parameters

2026-05-25  jirka <jirka@sdf.org>
	- Fix: Element load q was not selectable by mouse

2026-05-24  jirka <jirka@sdf.org>

	* Version 1.7.2
	- Fix: Explicitly reset/unset current_result_type in make_empty_data for clean state

2026-05-24  jirka <jirka@sdf.org>

	* Version 1.7.1
	- Fix: Increased Moment plot multiplier for better visibility compared to N forces
	- Fix: Zoom/Unzoom results menu items now correctly restore result display
	- Compatibility: Refactored lsort -index for Tcl 8.0 compliance

2026-05-23  jirka <jirka@sdf.org>

	* Version 1.7.0 (571fd99)
	- Major: Eurocode 3 (Steel) Lateral-Torsional Buckling (LTB) check
	- Major: Enhanced Section Library with out-of-plane properties (Iz, It, Iw)
	- Major: Model Healer v2 with "Update Section Properties" feature
	- Fix: Further corrections to bending moment (M) computation
	- Fix: Stability analysis now correctly handles updated section properties

2026-05-23  jirka <jirka@sdf.org>

	* Version 1.6.4 (9b0e1b4)
	- Fix: M, V, N results and plotting signs corrected (tension positive for N)
	- Fix: Nodal load sign convention corrected in all solvers
	- Fix: Bending moment diagrams now physically accurate and plotted on tension side
	- Fix: Reactions are now only shown for constrained degrees of freedom
	- Fix: Support for load combinations and permanent load case (LC 0) in results and plotting
	- Fix: Reaction calculations and equivalent nodal loads signs corrected
	- Fix: Tcl 8.0 compatibility in transformation matrices and glob usage
	- Fix: Formatting of deformation labels and handling of small multipliers
	- Test: Added test_solvers.df, test_ec_steel.df, and test_large_def.df

2026-05-23  jirka <jirka@sdf.org>

	* Version 1.6.3
	- Fix: Input sanitization in check_set_node (handles commas, spaces, empty values)
	- Fix: Element side panel update logic (update_side_panel used after apply)
	- Fix: Added plot_stuff to several UI actions (Node, Element, Disp, Force)
	- Refactor: delete_elements renamed to delete_elem for consistency
	- Refactor: Removed debug prints in delete_node and change_node
	- Fix: change_node and change_elem now correctly handle processing state

2026-05-22  jirka <jirka@sdf.org>

	* Version 1.6.2 (3b724d0)
	- EC Steel update + bugfixes

2026-05-21  jirka <jirka@sdf.org>

	* Version 1.6.1 (8088842)
	- new files, plugin system
	- more EC and fixes (a523232)

2026-05-20  jirka <jirka@sdf.org>

	* Version 1.5.0 (2ecb357)
	- outputs refactored
	- docs updated (f8b3326)

2026-05-19  jirka <jirka@sdf.org>

	* Version 1.4.0 (bb1a29f)
	- new materials fixes, matrix speedup
	- large deformations and basic EC modules (untested) (6fa9130, 2bb41d6)
	- Remove unimplemented 'Plastic Collapse' menu item (164351c)
	- Fix domain error in geometric stiffness (e7167f7)
	- Fix syntax errors in mat_vec_mult6 (d7c8740, 0cbab4f)
	- Improve robustness of mat_vec_mult6 (337a6b1)
	- Update Unix man page with Large Deformation and EC features (d6a7279)
	- Update Theory Manual and presentation (58a13dc, 42689a1, d7453a6)
	- Fix Large Deformation division by zero (dc7f89d)
	- Implement Large Deformation (3rd-Order) Analysis (3bd9eb8)
	- detailed markdown report + fixes (4f10ff5)
	- bugfixes - XFig (f0cc3a3)

2026-05-18  jirka <jirka@sdf.org>

	* Version 1.3.3 (b14db0b)
	- version number update
	- Plastic Collapse Analysis, Truss/Arc Wizards, and Metadata visibility (397d855)
	- wizards (e3e7a8e)
	- TODO update (8d9030e)

2026-05-17  jirka <jirka@sdf.org>

	* Version 1.3.2 (e93317e)
	- Version number update
	- version update (274f169)
	- simple file for snow testing (94234d1)

2026-05-16  jirka <jirka@sdf.org>

	* Version 1.3.1 (456c165)
	- Version update

2026-05-15  jirka <jirka@sdf.org>

	* Version 1.3.0 (d3e0dc8)
	- new load symbolics
	- Deformations multiplier (8a60b4c)
	- materials library, model control (5bf8b08)

2026-05-14  jirka <jirka@sdf.org>

	* Version 1.2.2 (7247722)
	- sections, combinations and undo

2026-05-13  jirka <jirka@sdf.org>

	* Version 1.2.1 (cd77bff)
	- Configuration file handling and compatibility fixes
	* Version 1.2.0 (d292dd0)
	- Updated version with stability and dynamics

2020-09-04  jirka <jirka@sdf.org>

	* Version 1.1.7 (bbbafbd)
	- basic deformed stucture plot as independent function

2020-09-03  jirka <jirka@sdf.org>

	* Version 1.1.6 (04f9254)
	- version and comments update
	* Version 1.1.5 (ef4face)
	- version set
	* Version 1.1.3
	- Initial versioning in About box
	* Version 1.1.1
	- Added BIM export
	* Version 1.0.5
	- Major stable release
	* Version 0.2.2
	- Fix: Element load plotting
	* Version 0.2.1
	- Internal beta
	* Version 0.1.1
	- First release
