CHANGELOG

All notable changes between the original voxmapper.py (tkinter) and the current voxmapper_qt.py (PyQt6) implementation.

This changelog summarizes refactors, new features, bug fixes, and behavioral differences introduced when the project was migrated and modernized.

v1.4.2 (migration -> PyQt6 & improvements)

Rewrote UI from tkinter (voxmapper.py) to PyQt6 (voxmapper_qt.py). The application now uses a MainWindow class and modular UI builders in ui_builder.py.
UI construction split into separate builders: build_noise_ui, build_grass_ui, build_landmass_ui, build_image_ui.
Theme handling extracted to a ThemeManager (theme_worker.py) and applied at startup.
Worker logic moved into dedicated worker threads in preview_workers.py (e.g., NoiseWorker, GrassWorker, LandmassWorker, ImageWorker, GenerateHeightmapWorker, GrassExportWorker). This replaces older inline threading/multiprocessing usage.
Executor/manager pattern introduced (executor_manager.py) to handle multiprocessing pools for chunked noise generation.

Consistent modern Qt UI with tabbed interface: Noise, Landmass, Grass Map, Image Import.
Preview canvases implemented with QLabel widgets showing scaled QPixmap/QImage from PIL conversions.
Interactive preview pan and zoom implemented using eventFilter on preview labels (mouse drag + wheel zoom) while preserving focus mapping between preview and export.
Zoom and position indicators added to UI (zoom_label, position_label) and updated during interactions.
Sliders linked to spinboxes with helper _link_slider_to_spinbox for consistent UX.

Export operations (heightmap/generations) now provide visible progress bars and cancel buttons:
- Noise heightmap export uses export_progress (universal) above the Noise preview.
- Grass export has grass_export_progress above the Grass preview and a GrassExportWorker that emits progress updates per-row.
- Landmass export now has land_export_progress above the Landmass preview and uses GenerateHeightmapWorker progress updates for multiprocess stages.
Cancel button wired to request thread interruption (requestInterruption) and sets shared flags where applicable.
Export cleanup consolidated in _export_finished_cleanup which hides and resets all progress bars and disconnects worker signals.

Noise generation moved into chunked multiprocessing via executor_manager and worker helpers; results are stitched together (np.vstack) and post-processed through create_heightmap.
GenerateHeightmapWorker reports progress across multiple stages (noise generation, postprocessing, saving) via progress signal.
GrassExportWorker added and implemented to emit progress and support cancellation; exports grass maps directly from a worker thread.
start_noise_worker helper returns a started NoiseWorker and adds a cancel convenience method.

Image import and processing use PIL with safe pil_to_qimage helper producing deep-copied QImage to avoid use-after-free crashes.
Image preview updates run in ImageWorker thread to keep UI responsive.
Grayscale conversion, green overlay, gaussian blur, and other filters handled more robustly (PIL ImageFilter, numpy operations).

Added a Qt-friendly top-level exception hook qt_exception_hook to show errors in message boxes while printing stack traces to console.
Extensive try/except usage to avoid crashing the GUI from worker exceptions.
Logging improved through Python logging calls for debug and error visibility.
Graceful worker interruption attempts: workers are requested to stop and waited for briefly before forced termination.

Fixed landmass export cleanup bug (incorrect self._export.finished_cleanup reference) -> now connects to _export_finished_cleanup.
Progress bars for Grass and Landmass exports added (user-visible progress previously absent for grass exports).
Preview-scaling mapping: preview zoom/scale accounting improved so exports match the preview view (store _last_preview_effective_scale and use to compute export scale).
Safe QImage conversion to avoid GUI crashes when worker threads exit (deep copy strategy in pil_to_qimage).

tkinter UI removed entirely; legacy voxmapper.py functions and tk widgets replaced by PyQt equivalents.
Some tightly-coupled inline functions in the old monolith split into smaller modules (e.g., ui_builder.py, preview_workers.py, executor_manager.py, workers_utils.py).

Project structure changed — new modules to review: ui_builder.py, preview_workers.py, executor_manager.py, theme_worker.py, workers_utils.py.
README version bumped to v1.4.2 and short notes added.