Daylon Graphics Ltd.

Mmm more firepower for Leveller. A new tool called Gradient Select was added. It lets heightfield effects be modulated gradually by creating a selection with linear or radial selection transparencies. What had to be done with a grayscale editor and mask import can now be done with a few clicks.

Somehow in all the excitement, I overlooked including an Intersect mode for Leveller's raster selection modifying. This is being rectified, starting with the Integrate Selection dialog and the Rectangular, Elliptical, and Arbitrary Select tools. Intersect lets you limit a selection to the intersection of the previously selected area and the new area being created. Since I'm out of keys for choosing modification modes via keyboard, the aforementioned tools now include a Style menu in their settings panel which makes any of the modification styles available (Replace, Union, Subtract, Invert, and now Intersect).

Leveller has a new plug-in filter called Slope Cutter, which combines the effects of its Lakebed and Mesa plug-ins. One can flatten an area within a selection, and connect to its edges using a constant slope regardless of whether the flat area is above or below the edge.

Leveller gains a new filter called Flatten. It lets the selected area be flattened to a particular elevation, or to the average/min/max/midpoint/percentage of the selected area's span. If nothing is selected, the entire heightfield's span is used.

The GDAL and PROJ libraries used by Leveller to implement many import/export operations and geographic coordinate system support have been updated to 3.11.3 and 9.6.2, respectively. The Datum/Projection dialog has also been revamped to make using predefined coordinate systems easier and more informative, and prevent errors from ground extents being out of bounds. More GDAL drivers are also available, but will be enabled on an ongoing basis.

Leveller's Text tool now has a "vector" option to let the text glyphs be rendered as vector shapes. This can be useful when using a symbol or dingbat font to quickly and easily create shapes from common geometries.

Leveller now features slope map visualization. The picture below shows an eroded gforge terrain with a simple snow slope map where steep areas are dark gray and gentle slopes are white. Like colormaps, slope color tables can be customized.

Leveller now uses an Undo buffer keyframe for each document's initial state, cutting document memory use in half which can be hundreds of MB for large heightfields.

One of Leveller's long-standing annoyances has finally been overcome. With the use of keyframes, edits that normally take a long time to perform (as part of action playback when undoing, redoing, or arbitrarily moving to a particular edit) can now be automatically replaced by an edit that uses disk space to store a complete copy of the modified document state. Creating and reading back these temporary files takes little time thanks to today's SSD and NVMe disk technology. You can e.g. run an Erosion filter that takes several seconds or a minute, and then be able to undo/redo in under a second.

As part of ongoing efforts to make Leveller's Undo command faster, heightfield modification actions now use compression to increase the probability of being immediately undoable.