A group whose only unlocked member is a shape (its other members
locked) kept a centre of (0,0), so Centrer horizontalement and
Centrer verticalement pulled every item toward the folio origin and
the shape itself landed off the line. The rule that turns a group's
members into one item now lives in Alignment::combined(), where every
member, shapes included, brings its own centre, and tst_alignment
covers it.
Also comments why unitFor()'s returned reference is safe, as asked in
the review of #1087.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01G2d2Zi8BfrYRPX88zhaoFG
Edit > Aligner gains six commands, also in the selection's context menu
and the command search: Aligner à gauche, Centrer horizontalement,
Aligner à droite, Aligner en haut, Centrer verticalement, Aligner en bas.
One undo step; wires follow their symbols. Second stage of discussion
#1069, on top of "Aligner sur la grille".
Left/right/top/bottom line the edges up on the outermost one. The two
centre commands line the items up on the mean of their centres, and a
symbol's centre is its origin point, not the middle of its drawing: in
the collection, vertical two-terminal symbols almost always have their
terminals on the origin's axis, so this puts their wires on one line.
A picture is aligned by the picture itself, without its caption
(imageRect() becomes public for this).
A group (#1070) lines up as one piece: its edges are its members'
together, and every member moves by the same amount, so the group keeps
its shape; shapes inside a group come along.
Each item moves only across the line it is aligned on, and lands on the
grid its drag uses, so aligning never takes a symbol off the grid. Two
symbols whose edges sit at different distances from their origins
cannot both be exactly on the line and on the grid; they end up within
half a grid step of it.
The commands need two items (Aligner sur la grille still needs one).
Locked items stay put and the status bar says so. If nothing moves, no
undo step is pushed and the status bar says the selection is already
aligned as far as the grid allows. The geometry is in alignment.h,
tested by tst_alignment.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Edit > Aligner > Aligner sur la grille, also in the selection's
context menu and the command search, puts each selected item back where
dragging it would have left it: symbols and pictures on the folio grid,
free texts on the text grid. One undo step; wires follow their symbols.
Symbols leave the grid through the fine nudge (Alt+arrow, 1 px), and
nothing put them back: 508 of the 3,678 symbols in the example projects
are off the 10 px grid. First stage of discussion #1069.
The status bar says how many items moved, or that the selection was
already on the grid, and how many locked items were left in place.
Shapes are left out: they are made of several points and no single one
is the obvious one to snap.
The snap never reads the keyboard, unlike Diagram::snapToGrid(), so a
user who binds the action to a shortcut with Ctrl gets the grid, not
pixel rounding. The geometry is in alignment.h, tested by tst_alignment.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01G2d2Zi8BfrYRPX88zhaoFG
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