commit 218876a9c1d446e99f769452e8d7de0a88ca359f
from: ale <ale_bnes@tuta.com>
date: Sun Aug 30 01:07:42 2026 UTC

Size figures from the measured height of the slide's prose

computeMediaBudget now renders the slide's text alone -- images and $$
blocks removed, captions kept -- and measures how many rows it actually
occupies at the current width, then splits the remaining height across
the media items. Replaces the fixed reservedRows guess, which was too
small when a slide carried a paragraph or a bullet list around the
figure, so the figure overran the text beneath it (or pushed it off the
bottom). Cached in Model.mediaRows and refreshed on every page change and
resize, so the fit re-measures as Kitty's font size changes.

commit - 502e0d5bb61287accc4380aa23b380a8929faf1b
commit + 218876a9c1d446e99f769452e8d7de0a88ca359f
blob - df3e4fec2c678e864b42e6ab4ee50929f564c3b0
blob + 2ee9d2b5ee2c3bfcbc86cc955df2f4c4e32814a9
--- internal/model/model.go
+++ internal/model/model.go
@@ -66,7 +66,13 @@ type Model struct {
 	images     *image.Cache
 	graphicsOK bool
 	darkBG     bool
-	spinner    spinner.Model
+	// mediaRows is the per-item row budget for the current slide's images
+	// and $$ blocks. Recomputed (from the measured height of the slide's
+	// prose) whenever the page or the viewport size changes, so figures
+	// shrink to leave room for whatever text shares the slide and follow
+	// Kitty's font-size / zoom live.
+	mediaRows int
+	spinner   spinner.Model
 	// step is the current slide's reveal progress, an index into
 	// reveal.Steps(current slide).
 	step int
@@ -156,22 +162,38 @@ func (m *Model) leftMargin() int {
 }
 
 // mediaSize returns the column/row budget for one media item on the
-// current slide. See mediaBudget.
+// current slide: the full content width, and the per-item row budget
+// computed by refreshMediaBudget (with a conservative fallback for the
+// first frame, before any WindowSizeMsg has arrived).
 func (m *Model) mediaSize() (maxCols, maxRows int) {
-	slide := ""
-	if m.Page >= 0 && m.Page < len(m.Slides) {
-		slide = m.Slides[m.Page]
+	contentWidth, contentHeight := m.contentSize()
+	maxRows = m.mediaRows
+	if maxRows < 3 {
+		maxRows = contentHeight - 10
+		if maxRows < 3 {
+			maxRows = 3
+		}
 	}
-	return m.mediaBudget(slide)
+	return contentWidth, maxRows
 }
 
-// mediaBudget splits the slide's usable height across every media item it
-// carries -- each ![](…) image and each $$…$$ block is a real graphic --
-// so several stacked figures/equations all fit inside the viewport
-// instead of the last one being clipped off the bottom. It is recomputed
-// on every resize (WindowSizeMsg), so the budget tracks Kitty's
-// font-size / zoom changes live.
-func (m *Model) mediaBudget(slide string) (maxCols, maxRows int) {
+// refreshMediaBudget recomputes mediaRows for the current slide. Call it
+// whenever the page or viewport size changes, before mediaSize is read.
+func (m *Model) refreshMediaBudget() {
+	if m.Page < 0 || m.Page >= len(m.Slides) {
+		return
+	}
+	m.mediaRows = m.computeMediaBudget(m.Slides[m.Page])
+}
+
+// computeMediaBudget returns how many rows one image or $$ block on slide
+// may use. It renders the slide's prose alone -- every image and display
+// block removed -- to measure how many rows the surrounding text really
+// occupies at the current width, then splits what's left evenly across
+// the media items. This is what keeps a figure from overrunning the
+// caption or paragraph beneath it, and it re-measures on every resize so
+// the fit tracks Kitty's zoom.
+func (m *Model) computeMediaBudget(slide string) int {
 	contentWidth, contentHeight := m.contentSize()
 
 	n := len(image.Parse(slide))
@@ -179,24 +201,40 @@ func (m *Model) mediaBudget(slide string) (maxCols, ma
 		n += len(blocks)
 	}
 	if n < 1 {
-		n = 1
+		return contentHeight
 	}
 
-	// Fixed allowance for text sharing the slide (title, intro line,
-	// status bar) plus, per media item, its caption and a blank line of
-	// separation. Fixed rather than a fraction of the viewport, so it
-	// still leaves room for fixed-size text once the viewport gets small
-	// after zooming in.
-	reserved := 6 + 2*n
+	textRows := 3
+	if r, err := glamour.NewTermRenderer(m.Theme, glamour.WithWordWrap(contentWidth)); err == nil {
+		if out, rerr := r.Render(code.HideComments(stripMedia(slide))); rerr == nil {
+			textRows = lipgloss.Height(strings.TrimRight(out, "\n"))
+		}
+	}
+
+	// styles.Slide's Padding(1) (2 rows) + the status bar and its padding
+	// (~3 rows) + one row of separation per media item + a small cushion so
+	// a slightly-off prose measurement never spills past the last row.
+	reserved := textRows + 7 + n
 	budget := contentHeight - reserved
 	if budget < 3*n {
 		budget = 3 * n
 	}
-	maxRows = budget / n
-	if maxRows < 3 {
-		maxRows = 3
+	return budget / n
+}
+
+// stripMedia removes a slide's images and $$ blocks but keeps each
+// image's caption as a line of text, so computeMediaBudget measures the
+// prose that will actually surround the figures.
+func stripMedia(slide string) string {
+	_, slide = latex.ParseDisplay(slide) // display blocks -> equal-length spaces
+	for _, ref := range image.Parse(slide) {
+		repl := ""
+		if ref.Caption != "" {
+			repl = "*" + ref.Caption + "*"
+		}
+		slide = strings.Replace(slide, ref.Raw, repl, 1)
 	}
-	return contentWidth, maxRows
+	return slide
 }
 
 // execMediaSize is the column/row budget for a code execution's plot: half
@@ -427,6 +465,7 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd
 	case tea.WindowSizeMsg:
 		m.viewport.SetWidth(msg.Width)
 		m.viewport.SetHeight(msg.Height)
+		m.refreshMediaBudget()
 		if !m.graphicsOK || len(m.Slides) == 0 {
 			return m, nil
 		}
@@ -535,6 +574,7 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd
 				}
 			}
 
+			m.refreshMediaBudget()
 			if !m.graphicsOK {
 				return m, nil
 			}
@@ -545,6 +585,7 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd
 	case uv.KittyGraphicsEvent:
 		if msg.Options.ID == image.ProbeID && string(msg.Payload) == "OK" {
 			m.graphicsOK = true
+			m.refreshMediaBudget()
 			maxCols, maxRows := m.mediaSize()
 			return m, loadImagesCmd(m.images, m.imageBaseDir(), m.Slides[m.Page], maxCols, maxRows, m.darkBG)
 		}
@@ -586,6 +627,7 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd
 			if m.Page >= len(m.Slides) {
 				m.Page = len(m.Slides) - 1
 			}
+			m.refreshMediaBudget()
 		}
 		return m, fileWatchCmd()
 	}