Incremental Reveals

Incremental reveals let you unveil slide content step by step as you advance through the presentation, keeping the audience focused on one point at a time.

MaTiSSe provides three mechanisms:

Mechanism	Syntax	Backend support
Incremental list	::: {.incremental}	impress.js + reveal.js
Pause token	. . .	impress.js + reveal.js
Substep block	$substep … $endsubstep	impress.js only

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Incremental lists

Wrap a bullet list in a {.incremental} fenced div to reveal each item individually:

::: {.incremental}
- First claim — shown alone
- Second claim — appears next
- Third claim — appears last
:::

Each <li> receives class="substep" (impress.js) or class="fragment" (reveal.js) so the respective framework hides and reveals them on forward navigation.

Mixing with regular lists

Only the items inside the {.incremental} block are revealed incrementally. Regular lists elsewhere on the same slide appear all at once:

These points appear immediately:

- Background assumption 1
- Background assumption 2

These are revealed one by one:

::: {.incremental}
- Novel contribution A
- Novel contribution B
- Novel contribution C
:::

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Pause token

Insert . . . (three dots separated by spaces) on its own line to split slide content at that point. Everything before the pause is shown first; subsequent content is revealed on the next forward press.

#### Algorithmic idea

We start from a feasible point $x_0$.

. . .

At each step we compute the gradient $\nabla f(x_k)$.

. . .

We then set $x_{k+1} = x_k - \alpha \nabla f(x_k)$ and repeat.

The pause token works anywhere inside slide content — between paragraphs, after a list, before a figure, etc.

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Substep blocks (impress.js)

For finer control over what is hidden and when, use explicit $substep / $endsubstep blocks. Each block wraps arbitrary content in a <div class="substep"> element, which the impress.js Substep plugin hides initially and reveals on forward navigation.

$substep
This paragraph is revealed at step 1.
$endsubstep

$substep
This equation is revealed at step 2.

$$E = mc^2$$
$endsubstep

Grouped substeps

Use the order:N option to reveal multiple blocks simultaneously:

$substep[order:1]
Left column content — appears together with the right column.
$endsubstep

$substep[order:1]
Right column content — same reveal step as left column.
$endsubstep

$substep[order:2]
This appears next, after both columns are visible.
$endsubstep

Substeps are impress.js only. The reveal.js backend does not support $substep / $endsubstep. Use ::: {.incremental} or . . . for cross-backend compatible reveals.

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Backend differences

Feature	impress.js	reveal.js
{.incremental} class	substep	fragment
. . . pause	Substep split	Fragment split
$substep blocks	✓ supported	✗ not supported
Reveal order	Sequential	Sequential

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See also

• reveal.js backend — overview mode, speaker notes, fragments
• Columns — multi-column layouts (combine with incremental)
• Callout Blocks — emphasis boxes (can appear as substeps)