* craft-dxf: model, the drawing above the tags (header, tables, blocks, layouts)
Document::read indexes a tag list into header variables, table records,
blocks with their entities, the ENTITIES records (a POLYLINE with its
vertices, an INSERT with its attributes) and the objects, each a slice of the
tag list. The typed table records, LAYOUT and DICTIONARY are made on request.
Also the colour index palette, colour, lineweight and transparency values,
extended data lookup and the object coordinate system.
Merged from CADCraft's cadcraft-io dxf_read (5a6aa9b6) and VectorCraft's
vectorcraft-cad import (566f7208). Neither app's document types appear.
* craft-dxf: model entities (geometry, text, MTEXT columns, hatches, dimensions)
Entity::read types an entity record: the properties every entity has, and
LINE, POINT, CIRCLE, ARC, ELLIPSE, LWPOLYLINE, POLYLINE with its vertices
(2D, 3D, mesh, polyface), SPLINE, RAY, XLINE, TEXT, MTEXT with columns,
ATTDEF, INSERT with its attributes (multiline ones included), DIMENSION,
LEADER, SOLID, TRACE, 3DFACE, HATCH (polyline and edge loops, pattern lines,
seeds, gradient), VIEWPORT, IMAGE, WIPEOUT and TOLERANCE. Other types stay
readable from the record's tags. model::text has the caret encoding of
strings, both ways.
Merged from CADCraft's cadcraft-io dxf_read (5a6aa9b6) and VectorCraft's
vectorcraft-cad import (566f7208).
* craft-dxf: a hatch spline edge without fit data leaves the loop's source count
Before R2010 a spline edge has no 97 of its own, so the 97 after it counts the
loop's source entities. It was read as the edge's fit point count and the
sources were lost.
* craft-dxf: model::write, a drawing as tags (R12 to 2018)
Drawing::tags writes the header, classes, the nine symbol tables, blocks,
entities and (R2000 and later) the dictionaries, plot style placeholder and
layouts around the layers, linetypes, styles, dimension styles, blocks and
entities it is given, in the model's own types. entity_tags writes one entity
for a caller with its own file. Handles given with the content are kept;
the rest are numbered after them.
The file skeleton is VectorCraft's vectorcraft-cad writer.rs (566f7208); the
MTEXT column groups are CADCraft's dxf_read/mtext_dxf.rs column_tags
(5a6aa9b6).
* README: keep main's crate list after the merge
