Alain Matthes submitted an update to the

tkz-elements

package.

Version: 4.35c 2025-11-08 License: lppl1.3c

Summary description: A Lua library for drawing Euclidean geometry with TikZ or tkz-euclide

Announcement text: ----------------------------------------------------------------------

This release introduces major internal improvements, new geometric tools, and the first public integration of Apollonius-related constructions. Improved geometric engine. Numerous internal optimisations and structural clean-up of the Lua codebase. Better consistency between object interfaces (point, line, circle, path, …). Unified system for solution outputs using paths (path objects storing centres and through-points). New or enhanced methods Robust tests for circle tangency (circle:are_circles_tangents()). Improved numerical tolerance control (tkz.epsilon, tkz.approx()). Expanded geometry toolbox: pole of a line w.r.t a circle, inversion-based utilities, projections, affine transformations. Apollonius problems – experimental implementation First complete framework for solving classical Apollonius configurations (CCC, CCL, CLP, LPP, etc.). Implementations include Viète reduction, homothety and inversion approaches. Solutions are returned as paths (pa_center, pa_through) with consistent structure, ready for TikZ drawing.

Important note on Apollonius methods The methods related to Apollonius' circle problems are still experimental. Although many generic cases are already handled (disjoint circles, external/internal tangencies, equal or unequal radii), the following must be kept in mind: Some special or degenerate cases are not yet fully covered, e.g.: three mutually secant circles, double contact with equal radii and aligned centres, combinations of internal/external tangency near inversion singularities. Corner cases may still produce missing or duplicated solutions. The code is evolving: names, internal strategies, and outputs may slightly change in future releases. These additions are intended as a research and development module, not yet as a final, guaranteed solver for all configurations. Documentation & usage The user manual (doc/tkz-elements.pdf) has been updated accordingly. A dedicated section on Apollonius problems explains: Syntax, returned paths, modes ("external", "internal", "all"), Example TikZ figures using tkz-euclide, Limitations and known edge cases.

----------------------------------------------------------------------

The package’s Catalogue entry can be viewed at https://ctan.org/pkg/tkz-elements

The package’s files themselves can be inspected at https://mirrors.ctan.org/macros/latex/contrib/tkz/tkz-elements/

------------------------------------------------------------------------

Thanks for the upload.

For the CTAN Team Petra Rübe-Pugliese

------------------------------------------------------------------------

CTAN is run entirely by volunteers and supported by TeX user groups. Please join a user group or donate to one, see https://ctan.org/lugs