Add Terminal.text_sized() kitty text sizing

.github/FUNDING.yml

@@ -0,0 +1 @@
+github: jquast

.spelling-ignore-words.txt

@@ -5,3 +5,4 @@ THIRDPARTY
 claus
 hel
 rin
+nd

bin/benchmark_sequences.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 """Benchmark blessed text manipulation functions."""
+
 import timeit
 from blessed import Terminal
 

bin/bounce.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python
 """Classic game of tennis."""
+
 # std imports
 from math import floor
 

bin/screen-scrape.py

@@ -178,7 +178,7 @@ def main():
     alt_clean = UNKNOWN_CKSUM_RE.sub(" ", alt)
 
     # If both screens are identical, the terminal doesn't support
-    # alternate buffer — store only screen 0.
+    # alternate buffer: store only screen 0.
     if normal_clean == alt_clean:
         alt_clean = None
         alt = None

bin/scroller.py

@@ -0,0 +1,163 @@
+#!/usr/bin/env python
+"""Demoscene sine-wave scroller with per-character text sizing."""
+import math
+import time
+import blessed
+from wcwidth import TextSizing, TextSizingParams, iter_graphemes, wcswidth
+
+FRACTIONS = [(n, d) for d in range(1, 16) for n in range(0, d)]
+
+
+def _nearest_fraction(numerator, denominator, fractions):
+    target = numerator / denominator
+    return min(fractions, key=lambda f: abs(target - f[0] / f[1]))
+
+
+def _scale_params(target):
+    if 0.97 <= target <= 1.03:
+        return 1, 0, 0, 0
+    if target < 1.0:
+        n, d = _nearest_fraction(round(target * 100), 100, FRACTIONS)
+        if n >= d or n == 0:
+            return 1, 0, 0, 0
+        return 1, 0, n, d
+    s = min(7, max(1, math.ceil(target)))
+    if target >= s - 0.03:
+        return s, 0, 0, 0
+    ratio = target / s
+    n, d = _nearest_fraction(round(ratio * 100), 100, FRACTIONS)
+    if n >= d:
+        return s, 0, 0, 0
+    return s, 0, n, d
+
+
+def _lerp(a, b, t):
+    return int(a + (b - a) * t)
+
+
+def _fire_color(t):
+    t = max(0.0, min(1.0, t))
+    if t < 0.5:
+        u = t / 0.5
+        r, g, b = _lerp(255, 255, u), _lerp(40, 160, u), _lerp(0, 0, u)
+    else:
+        u = (t - 0.5) / 0.5
+        r, g, b = _lerp(255, 255, u), _lerp(160, 240, u), _lerp(0, 32, u)
+    return f'\x1b[38;2;{r};{g};{b}m'
+
+
+_BLOCKS = (
+    '\u2588\u258c\u2590'
+    '\u2580\u2584'
+    '\u2591\u2592\u2593'
+    '\u2596\u2597\u2598\u259d'
+    '\u259a\u259e'
+)
+
+_MESSAGE = (
+    f'{_BLOCKS}  '
+    'Greetings to the modern terminal demoscene!  '
+    f'{_BLOCKS}  '
+    'Check out kitty\'s text sizing protocol  '
+    f'{_BLOCKS}  '
+    'unicode: \u6f22\u5b57\u30ab\u30bf\u30ab\u30ca  '
+    f'emoji: \U0001f680\U0001f47e\U0001f3b5\U0001f31f  '
+    f'{_BLOCKS}  '
+)
+
+
+def _sized_char(ch, target, term, v_align=0, h_align=0):
+    if not term.does_text_sizing().scale:
+        return ch, wcswidth(ch)
+    s, w, n, d = _scale_params(target)
+    if s == 1 and n == 0:
+        return ch, wcswidth(ch)
+    params = TextSizingParams(
+        scale=s, width=w, numerator=n, denominator=d,
+        vertical_align=v_align, horizontal_align=h_align)
+    seq = TextSizing(params, ch, '\x07').make_sequence()
+    width = TextSizing(params, ch, '\x07').display_width()
+    return seq, width
+
+
+def main():
+    term = blessed.Terminal()
+    screen_w = term.width
+    screen_h = term.height
+    vert_amp = screen_h // 3
+
+    graphemes = list(iter_graphemes(_MESSAGE))
+    graph_len = len(graphemes)
+
+    with term.cbreak(), term.hidden_cursor():
+        t = 0.0
+        scroll_pos = 0.0
+        bounce_phase = 0.0
+        paused = False
+
+        while True:
+            if term.kbhit(timeout=0):
+                key = term.inkey(timeout=0)
+                if key == 'q' or key == '\x03':
+                    break
+                if key == ' ':
+                    paused = not paused
+
+            if paused:
+                time.sleep(0.042)
+                continue
+
+            t += 1.0
+            scroll_pos += 0.003
+            bounce_phase += 0.0006
+
+            graph_offset = int(scroll_pos) % graph_len
+
+            base_freq = 2 * math.pi / screen_w
+            spatial_freq = base_freq * (0.2 + 1.8 * (math.sin(t * 0.0004) + 1.0) / 2.0)
+
+            col_scales = []
+            for col in range(screen_w):
+                norm = (math.sin(col * spatial_freq) + 1.0) / 2.0
+                col_scales.append(0.4 + norm * 3.55)
+
+            grapheme_idx = graph_offset
+            col = 0
+            buf = term.home + term.clear_eos
+
+            while col < screen_w:
+                gr = graphemes[grapheme_idx % graph_len]
+                grapheme_idx += 1
+                if col >= screen_w:
+                    break
+
+                target = col_scales[col]
+                sine_y = vert_amp * math.sin(col * spatial_freq + bounce_phase)
+                y = max(0, min(screen_h - 1, int(screen_h // 2 + sine_y)))
+
+                deriv = math.cos(col * spatial_freq + bounce_phase)
+                if deriv > 0.3:
+                    v = 1
+                elif deriv < -0.3:
+                    v = 0
+                else:
+                    v = 2
+
+                seq, cw = _sized_char(gr, target, term, v, v)
+                if col + cw > screen_w:
+                    break
+
+                lerp_t = (y - (screen_h // 2 - vert_amp)) / max(1, vert_amp * 2)
+                lerp_t += 0.15 * math.sin(t * 0.00035)
+                lerp_t = max(0.0, min(1.0, lerp_t))
+                fg = _fire_color(lerp_t)
+
+                buf += term.move_yx(y, col) + fg + seq
+                col += cw
+
+            with term.dec_modes_enabled(term.DecPrivateMode.SYNCHRONIZED_OUTPUT):
+                print(buf, end='', flush=True)
+
+
+if __name__ == '__main__':
+    main()

bin/set-xterm-title.py

@@ -0,0 +1,27 @@
+#!/usr/bin/env python3
+"""Set the xterm window title using blessed."""
+import argparse
+import sys
+
+from blessed import Terminal
+
+
+def main():
+    parser = argparse.ArgumentParser(description='Set the xterm window title.')
+    parser.add_argument('title', nargs='+', help='Title text to set.')
+    parser.add_argument('-m', '--mode', type=int, default=0, choices=[0, 1, 2],
+                        help='OSC mode: 0=both (default), 1=icon only, 2=title only.')
+    args = parser.parse_args()
+
+    term = Terminal()
+    title = ' '.join(args.title)
+    seq = term.set_window_title(title, mode=args.mode)
+    if not seq:
+        print('Terminal does not support styling.', file=sys.stderr)
+        raise SystemExit(1)
+    sys.stdout.write(seq)
+    sys.stdout.flush()
+
+
+if __name__ == '__main__':
+    main()