Game of Life page element and built-in page

A new page element runs Conway's Game of Life in an area (the whole display
by default), one per page. Start: random dots, one pattern, or the icons
whose names start with a text in turn or in random order. Edges: wrap
around, dead, or a hidden margin where gliders fly out of view (leftovers
that stay put in the margin are cleared, so a glider gun runs cleanly).
It restarts when the board is still or repeats within 16 generations
and/or after a number of generations, after a hold time (an empty board
at once).

logic/life holds the board and timing (tested), display/life_player runs
the board of the shown page, ticked before each frame; frames are paced
like scrolling text. The element reuses existing fields, so the page
format stays the same. The Icons tab has a library of 17 LifeWiki
patterns (checked with a simulation), and the built-in page "Game of
Life" shuffles through the life_ icons. About 12 KB flash, 8 KB RAM.

Version 2.17.0, tested on the display over OTA.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/esp32/logic/page_render.cpp

@@ -156,6 +156,62 @@ static void drawBar(const PageElement &e, PageResources &resources, uint8_t *bit
 		drawBarPercent(e, resources, bitmap, left + inner, e.y + inner, w - 2 * inner, h - 2 * inner);
 }
 
+// Life without a running board (a preview of a page that is not shown): the start, the
+// pattern in the middle or a random fill that is always the same, in area coordinates
+static void lifeStart(const PageElement &e, int w, int h, PageResources &resources, uint8_t *start)
+{
+	memset(start, 0, BITMAP_BYTES);
+	uint32_t random = 1;
+	uint8_t pattern[BITMAP_BYTES];
+	int dx, dy;
+	if (e.input_unit == LIFE_START_PATTERN)
+	{
+		if (!resources.background(e.text, pattern) || !lifePlacement(pattern, w, h, false, random, dx, dy))
+			return;
+		for (int y = 0; y < BITMAP_HEIGHT; y++)
+			for (int x = 0; x < BITMAP_WIDTH; x++)
+				if (bitmapPixel(pattern, x, y))
+					setBitmapPixel(start, x + dx, y + dy, true);
+		return;
+	}
+	int percent = e.input_unit == LIFE_START_RANDOM ? (int)e.factor : 30;
+	for (int y = 0; y < h; y++)
+		for (int x = 0; x < w; x++)
+			setBitmapPixel(start, x, y, (int)(lifeRandom(random) % 100) < percent);
+}
+
+// Life: the running board of the shown page; returns the ms until its next generation
+static uint32_t drawLife(const PageElement &e, uint32_t now_ms, PageResources &resources, uint8_t *bitmap,
+						 ElementBox &box)
+{
+	int w = e.bar_width, h = e.bar_height;
+	int left = e.x;
+	if (e.align == Align::Center)
+		left -= w / 2;
+	else if (e.align == Align::Right)
+		left -= w;
+	box.x = left;
+	box.y = e.y;
+	box.width = w;
+	box.height = h;
+	if (e.overlay == Overlay::Box)
+		clearBox(bitmap, left - 1, e.y - 1, w + 2, h + 2);
+
+	const LifeRunner *runner = resources.life(e);
+	uint8_t start[BITMAP_BYTES];
+	if (!runner)
+		lifeStart(e, w, h, resources, start);
+	for (int y = 0; y < h; y++)
+		for (int x = 0; x < w; x++)
+		{
+			if (!(runner ? runner->board.cell(x, y) : bitmapPixel(start, x, y)))
+				continue;
+			int bx = left + x, by = e.y + y;
+			setBitmapPixel(bitmap, bx, by, e.overlay == Overlay::Invert ? !bitmapPixel(bitmap, bx, by) : true);
+		}
+	return runner ? runner->msUntilNext(now_ms) : 0;
+}
+
 // A text element; returns the ms until it scrolls on (0: it doesn't scroll)
 static uint32_t drawTextElement(const PageElement &e, const char *text, uint32_t now_ms, PageResources &resources,
 								uint8_t *bitmap, ElementBox &box)
@@ -223,6 +279,8 @@ uint32_t renderPage(const DynamicPage &page, const LocalTime &time, uint32_t now
 			drawImage(e, resources, bitmap, box);
 		else if (e.type == ElementType::Bar)
 			drawBar(e, resources, bitmap, box);
+		else if (e.type == ElementType::Life)
+			next = sooner(next, drawLife(e, now_ms, resources, bitmap, box));
 		else
 		{
 			ElementValues values;