From 9c9be25bdb0b2ec48e3078fe5e119b3d0f56631c Mon Sep 17 00:00:00 2001 From: "Danilo M." Date: Wed, 16 Sep 2026 19:39:45 +0200 Subject: fix: step text cursors by advance, not ink width The date rendered as "16 /SEP /2026", each slash jammed against the next glyph. measure() returns the ink width, which ignores leading and trailing spaces because a space carries no ink, and clock.lua was using it to advance a cursor. Measured: " / " covers 6px of ink but advances 14px, so every separator lost 8px. Splits the two uses that were conflated in one function. measure() is for centring and right-aligning, where ink width is what you want; advance() returns x_advance and is for laying out runs of text left to right. The clock's date now uses advance() and reads "16 / SEP / 2026" with even gaps, verified by screenshot. Worth the split rather than changing measure() in place: text_right is a correct caller of the ink width, so one function cannot serve both and silently returning the advance would have broken alignment instead. Co-Authored-By: Claude Opus 5 --- lib/card.lua | 15 +++++++++++++++ 1 file changed, 15 insertions(+) (limited to 'lib') diff --git a/lib/card.lua b/lib/card.lua index 474228d..4d94465 100644 --- a/lib/card.lua +++ b/lib/card.lua @@ -44,11 +44,26 @@ end -- values before the next call overwrites them. local extents = cairo_text_extents_t:create() +-- Ink size of a string: how much space the glyphs actually cover. +-- Use this to CENTRE or RIGHT-ALIGN text, never to advance a cursor. function M.measure(cr, s) cairo_text_extents(cr, s, extents) return extents.width, extents.height end +-- How far the cursor moves after drawing a string. Use this to lay out runs of +-- text left to right. +-- +-- Not measure(): that returns the INK width, which ignores leading and +-- trailing spaces because a space carries no ink. Stepping a cursor by the ink +-- width collapses the gaps, and " / " measures 6px of ink against a 14px +-- advance, so a date drawn in segments came out as "16 /SEP /2026" with each +-- slash jammed into the next glyph. +function M.advance(cr, s) + cairo_text_extents(cr, s, extents) + return extents.x_advance +end + -- Right-aligned text: x is the RIGHT edge. function M.text_right(cr, x, y, s) local w = M.measure(cr, s) -- cgit v1.2.3