14.1 Make a title card🔗ℹ

(define welcome

(slide #:id 'welcome #:layout 'title

[title "Solving equations"]

[subtitle "Keep both sides equal."]))

(define welcome-picture

(slide->pict welcome))

> (slide? welcome)

#t

To give the card a duration, use (hold-slide welcome #:duration 3). A plain slide and its Pict do not have a movie duration. See Pict and Scene conversion.

14.2 Reveal one bullet at a time🔗ℹ

(define build-card

(slide #:id 'layout-title+body #:layout 'title+body

[title "Explain one idea"]

[body

(bullets

[structure "Choose a layout."]

[identity "Name what matters."]

[timing "Reveal it at the right moment."])]))

(define build-clip

(build-slide build-card #:initial 'hidden

(beat 'heading #:duration 0.7

(reveal-slot 'title))

(beat 'structure #:duration 0.9

(reveal-slot '(body structure)))

(beat 'identity #:duration 0.9

(reveal-slot '(body identity)))

(beat 'timing #:duration 0.9

(reveal-slot '(body timing)))

(beat 'read #:duration 1.6)))

> (slide-clip? build-clip)

#t

Select the second settled bullet state with (slide->pict build-clip #:at '(identity end)). To hide the complete list later, append a beat containing (conceal-slot 'body #:duration 0.5). To draw attention first, use emphasize-slot on a visible item. Neither operation frees layout space. See Slot actions.

14.3 Use your own theme🔗ℹ

(define base-type

(slide-theme-typography lecture-dark))

(define course-type

(typography-theme #:id 'course-type #:extends base-type

#:styles

(hash 'title

(text-style-update (typography-ref base-type 'title)

#:font-family 'roman #:font-size 0.72))))

(define course-theme

(slide-theme #:id 'course #:extends lecture-dark

#:typography course-type

#:spacing (hash 'safe-x 0.8 'column-gap 0.7)

#:decorations (hash 'title-rule? #t)))

> (slide-theme? course-theme)

#t

Use the theme on a storyboard or when converting an unprepared slide:

(define themed-picture

(slide->pict welcome #:theme course-theme))

This changes presentation settings; it does not rewrite welcome. The comparison below uses the built-in light and dark themes so the color change is easy to see.

A prepared slide already has a measured layout. Change the original description and prepare again. See Themes and formats.

14.4 Keep a title between slides🔗ℹ

Give corresponding contents a shared key, then match that key across a transition.

(define shared-title

(paragraph-content "Keep the idea" #:align 'left))

(define title-before

(slide #:layout 'title

[title #:key 'topic #:align 'center shared-title]

[subtitle "A centered introduction"]))

(define title-after

(slide #:layout 'title+body

[title #:key 'topic shared-title]

[body "The same prepared title moves to its new position."]))

(define title-film

(storyboard #:id 'manual-title-match #:theme lecture-dark

(storyboard-shot 'before (hold-slide title-before #:duration 1.2))

(slide-transition #:effect 'match #:keys '(topic)

#:duration 1 #:easing 'smooth)

(storyboard-shot 'after (hold-slide title-after #:duration 1.8))))

> (storyboard? title-film)

#t

The content keeps the key 'topic while the layout changes. See Storyboards and transitions.

14.5 Move children as their panel changes layout🔗ℹ

Semantic part names state which children continue into the next arrangement.

(define (make-idea-panel final?)

(define row

(semantic-group #:width 10 #:height 3

(semantic-part 'observe "Observe"

#:x (if final? 6 0) #:y 0 #:width 4 #:height 1.2)

(semantic-part 'explain "Explain"

#:x (if final? 0 6) #:y 1.6 #:width 4 #:height 1.2)))

(semantic-group #:width 12 #:height 6

(semantic-part 'ideas row

#:x (if final? 0 1) #:y (if final? 1.4 0.4)

#:width (if final? 9 10) #:height 3)

(semantic-part (if final? 'conclusion 'question)

(if final? "Connect the ideas." "What do we notice?")

#:x 1 #:y 4.5 #:width 10 #:height 1)))

(define parts-before

(slide #:layout 'title+figure

[title "The parts keep their identities"]

[figure #:key 'ideas (make-idea-panel #f)]))

(define parts-after

(slide #:layout 'title+figure

[title "The parts keep their identities"]

[body "The panel moves. Its named children rearrange independently."]

[figure #:key 'ideas (make-idea-panel #t)]))

(define parts-film

(storyboard #:id 'manual-parts #:theme lecture-dark

(storyboard-shot 'before (hold-slide parts-before #:duration 2))

(slide-transition #:effect 'match #:keys '(ideas) #:depth 'semantic

#:duration 2.5 #:easing 'smooth)

(storyboard-shot 'after (hold-slide parts-after #:duration 3))))

> (storyboard? parts-film)

#t

A part’s x/y coordinates are measured from its containing group’s top-left, not its center. See Named children and frozen checkpoints.

14.6 Move an equation while doing its algebra🔗ℹ

This example is intentionally kept as one complete program. Its derivation, presentation plan, checkpoints, and storyboard belong together, and preparing it uses the math typesetting toolchain.

Prepare with prepare-storyboard! before sampling the result. The bridge replays the authored derivation; it does not infer algebra from unrelated pictures. See Freeze a point in an existing animation and Named children and frozen checkpoints.

14.7 Reuse an animated construction🔗ℹ

This is also a complete-program example: the imported construction and slide wrapper are separate reusable pieces.

play-content starts the local animation; revealing the slot alone does not. Use the ordinary slide project runner for workers. See Render a slide video with ten workers.