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jwa91/twentse_ros_anim.py

Created March 10, 2026 23:01
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Ghostty style animation with "Twentse Ros"
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twentse_ros_anim.py
#!/usr/bin/env python3
"""
Twentse Ros - Pre-rendered ASCII animation for the terminal.
Ghostty-style smooth animation: pre-rendered frames, two colors,
character density for depth, subtle breathing wave.
Usage:
python3 twentse_ros_anim.py [ros_ascii.txt]
Ctrl+C to quit
"""
import math
import os
import signal
import sys
import time
from collections import deque
# --- Config ---
NUM_FRAMES = 180 # 6-second loop
FPS = 30
# --- ANSI ---
ESC = "\033"
HIDE_CURSOR = f"{ESC}[?25l"
SHOW_CURSOR = f"{ESC}[?25h"
CLEAR = f"{ESC}[2J"
HOME = f"{ESC}[H"
RESET = f"{ESC}[0m"
# Two colors: default terminal fg + Twente red accent
ACCENT = f"{ESC}[38;2;180;25;25m"
ACCENT_DIM = f"{ESC}[38;2;100;14;14m"
DEFAULT_FG = f"{ESC}[39m"
# --- Characters ---
# Body: ordered light → heavy (18 chars)
BODY_CHARS = "·.,;:-~=+*xo%S#@$W"
# Border: lighter decorative set
BORDER_CHARS = "·.+~*=-:"
# --- Density mapping from original ASCII ---
CHAR_DENSITY = {}
for c in "W": CHAR_DENSITY[c] = 1.0
for c in "#@": CHAR_DENSITY[c] = 0.9
for c in "%&$": CHAR_DENSITY[c] = 0.85
for c in "S": CHAR_DENSITY[c] = 0.75
for c in "E": CHAR_DENSITY[c] = 0.7
for c in "N": CHAR_DENSITY[c] = 0.6
for c in "AHMX": CHAR_DENSITY[c] = 0.55
for c in "0123456789": CHAR_DENSITY[c] = 0.5
for c in "abcdefghijklmnopqrstuvwxyz": CHAR_DENSITY[c] = 0.4
for c in "+=*?": CHAR_DENSITY[c] = 0.35
for c in "~-:;": CHAR_DENSITY[c] = 0.25
for c in ".,": CHAR_DENSITY[c] = 0.15
def density_to_char(d):
d = max(0.0, min(1.0, d))
return BODY_CHARS[int(d * (len(BODY_CHARS) - 1))]
def load_ascii_art(path):
with open(path) as f:
lines = [l.rstrip('\n') for l in f]
# Find bounding box of content
min_x = min_y = float('inf')
max_x = max_y = 0
for y, line in enumerate(lines):
for x, ch in enumerate(line):
if ch != ' ':
min_x = min(min_x, x)
max_x = max(max_x, x)
min_y = min(min_y, y)
max_y = max(max_y, y)
if min_x == float('inf'):
print("No content found!")
sys.exit(1)
# Add margin for the border aura
margin = 3
grid_x0 = max(0, min_x - margin)
grid_y0 = max(0, min_y - margin)
grid_x1 = max_x + margin
grid_y1 = max_y + margin
h = grid_y1 - grid_y0 + 1
w = grid_x1 - grid_x0 + 1
grid = []
for y in range(grid_y0, grid_y1 + 1):
row = []
for x in range(grid_x0, grid_x1 + 1):
ch = ' '
if 0 <= y < len(lines) and 0 <= x < len(lines[y]):
ch = lines[y][x]
row.append(ch)
grid.append(row)
return grid, w, h
def compute_outer_aura(grid, h, w, max_dist=2):
"""Find empty pixels near the OUTER edge of the horse only.
Flood-fills from the grid border to find all 'outside' empty pixels,
then computes distance from filled pixels for only those outside pixels.
Interior holes (like the eye) are excluded.
"""
# Step 1: flood-fill from edges to mark all "outside" empty pixels
outside = [[False] * w for _ in range(h)]
q = deque()
# Seed from all border cells that are empty
for y in range(h):
for x in range(w):
if (y == 0 or y == h - 1 or x == 0 or x == w - 1) and grid[y][x] == ' ':
outside[y][x] = True
q.append((x, y))
while q:
px, py = q.popleft()
for dx in (-1, 0, 1):
for dy in (-1, 0, 1):
if dx == 0 and dy == 0:
continue
nx, ny = px + dx, py + dy
if 0 <= nx < w and 0 <= ny < h and not outside[ny][nx] and grid[ny][nx] == ' ':
outside[ny][nx] = True
q.append((nx, ny))
# Step 2: BFS distance from filled pixels, but only for outside empty pixels
dist = [[999] * w for _ in range(h)]
q = deque()
for y in range(h):
for x in range(w):
if grid[y][x] != ' ':
dist[y][x] = 0
q.append((x, y))
while q:
px, py = q.popleft()
for dx in (-1, 0, 1):
for dy in (-1, 0, 1):
if dx == 0 and dy == 0:
continue
nx, ny = px + dx, py + dy
if 0 <= nx < w and 0 <= ny < h:
nd = dist[py][px] + 1
if nd < dist[ny][nx] and nd <= max_dist and outside[ny][nx]:
dist[ny][nx] = nd
q.append((nx, ny))
return dist
def generate_frames(grid, dist, h, w):
"""Pre-render all animation frames."""
frames = []
for f in range(NUM_FRAMES):
phase = f / NUM_FRAMES * 2.0 * math.pi
lines = []
for y in range(h):
parts = []
color_state = 'default'
ny = y / h
for x in range(w):
ch = grid[y][x]
pd = dist[y][x]
if ch != ' ':
# --- Body pixel: default terminal color, original char ---
if color_state != 'default':
parts.append(DEFAULT_FG)
color_state = 'default'
parts.append(ch)
elif 1 <= pd <= 2:
# --- Border aura: Twente red accent ---
# Slow traveling shimmer (whole-number multipliers = seamless loop)
s = math.sin(y * 0.15 + x * 0.1 + phase)
s += math.sin(y * 0.08 - x * 0.06 + phase * 2.0) * 0.4
# Show character when wave crest passes
thresh = 0.1 if pd == 1 else 0.5
if s > thresh:
want_color = ACCENT if pd == 1 else ACCENT_DIM
if color_state != want_color:
parts.append(want_color)
color_state = want_color
bci = int(abs(s * 5.0 + ny * 3.0)) % len(BORDER_CHARS)
parts.append(BORDER_CHARS[bci])
else:
if color_state != 'default':
parts.append(DEFAULT_FG)
color_state = 'default'
parts.append(' ')
else:
# --- Empty pixel ---
if color_state != 'default':
parts.append(DEFAULT_FG)
color_state = 'default'
parts.append(' ')
if color_state != 'default':
parts.append(DEFAULT_FG)
lines.append(''.join(parts))
frames.append(lines)
return frames
def main():
path = sys.argv[1] if len(sys.argv) > 1 else "ros_ascii.txt"
grid, w, h = load_ascii_art(path)
try:
term_w, term_h = os.get_terminal_size()
except OSError:
term_w, term_h = 120, 50
offset_x = max(0, (term_w - w) // 2)
offset_y = max(0, (term_h - h) // 2)
dist = compute_outer_aura(grid, h, w, max_dist=2)
sys.stderr.write("Generating frames...")
sys.stderr.flush()
frames = generate_frames(grid, dist, h, w)
sys.stderr.write(f" {NUM_FRAMES} frames ready.\n")
sys.stderr.flush()
# Setup terminal
sys.stdout.write(HIDE_CURSOR + CLEAR)
sys.stdout.flush()
def cleanup(sig=None, _frame=None):
sys.stdout.write(SHOW_CURSOR + RESET + CLEAR + HOME)
sys.stdout.flush()
sys.exit(0)
signal.signal(signal.SIGINT, cleanup)
signal.signal(signal.SIGTERM, cleanup)
frame_idx = 0
try:
while True:
frame_lines = frames[frame_idx % NUM_FRAMES]
buf = []
for y, line in enumerate(frame_lines):
row = offset_y + y + 1
if 1 <= row <= term_h:
buf.append(f"{ESC}[{row};{offset_x + 1}H{line}")
sys.stdout.write(''.join(buf))
sys.stdout.flush()
frame_idx += 1
time.sleep(1.0 / FPS)
except KeyboardInterrupt:
cleanup()
if __name__ == "__main__":
main()
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jwa91 commented Mar 10, 2026

ros_ascii.txt



                                                    SSN
                                                NS NSSSSSNS                  SJS
                                                SSSSWWWWWWSSSSSSSNNNS         SN
                                             SSSSWWWWWWWWWWWWWWS    NN     2  SN
                                            SSSSSSSSWWWWWWWWWWWSS          SNSN
                                           SSWSo   SWWWWWWWWWWWWSSS          NS
                                          SSSWSSSNSSWWWWWWWWWWWWWSN           SSj
                                        NSSWWWWWWWW2WWWWWWWWWWWSSSSSN         SSSS   NS
                      NNSNS           NSSWWWWWWWWWWSSSWWWWWWWWWS   S       Nf aSSSN  SSS
                    SSSSWSSJ        ESSWWWWWW2WWSSSW SWWWWWWWWWSSJ         SS SSWSS  SSJ
                  SSNSSSSSSS        NSSSSSSSSSSSW  SSSWWWWWWWWWSSSSSJ      SN SSSSN  SSS
               NSSSS     SSSSW       SSS        SSSSWWWWWWWWWWWN  2SSf    SSSSSSSa  SSSN
             SSSSS        SSSSS        fSSSSSSSSSW2WWWWWWWWWWWWN   NSW   SSWWWSS  SSSSS
           NSSWS          sSSWSSN   SSSSSWWWWWWWWWWWWWWWWWWWWSSSSN  a   SSWWWWWsfSSSSN
           SSWWSS          NSSSS  NSSSWWWWWWWWWWWWWWWWWWWWWWSSSSSSS     NSWWWWSSSS2SS    xNS
            NSWSS           SS  SSSWWWWWWWWWWWWWWWWWWWWWWSSSS   NSN      SSWWWWWWWSS      SS
             SSSS              NSSWWWWWWWWWWWWWWWWWWWWWWWS SNNJ  SSS      SSSWWWWWSS     NSS
            aNN               oSWWWWWWWWWWWWWWWWWWWWWWWWWS                 SSSWWWWSS  oNSSSS
                              SSWWWWWWWWWWWWWWWWWWWWWWSSSSNSJNNS        SNS  SSWWWSS SSSSSS
                 SSNSSSSSSSSSSSSWWWWWWWWWWWWWWW2WWWWW2S   x   7J         aSS  SSWWWSSSWWS
                 NSSSSNSSSSSSSSSSWWW2WWWWWSSSSSWWWWWWWSN                  SS   NSWWWWWWSS
                 SSSW          xSNSSSSSSSSSS  SWWWWWWWWSSj               SSS   xSWWWWWWSN
                 SSS                       2SSSWWWWWWWWWSSN              SSS    SWWWWWWSS
                 SS            SNSSSSSSSSSSSSWWWWWWWWWWWWSSS             SSSSS  S2W2WSSSW
                oSN              NSWWW2WWWWWWWWWWWWWWWWWWWWSSS            NSSSSSSWWSSS2
                SSS  7            NSSWWWWWWWWWWWWWWWWWWWWWWWSSSS           NSSW2WSSS  SSNS
                SSSSS2             2SSWWWWWWWWWWWWWWWWWWWWWWWWSSSSSSs        SSWWSS  SSN
                SS2SS                SSSWWWWWWWWWWWWWSSSSWWWWWWWWWSSSSSS      SWWS   SS
                SSSSS                  SSSWWWWWWWWWSSS  SWWWWWWWWWWWWWSSSS    SWWSS  SSo
                  SSSSSJ                 SSSSWWWWWSS SSSSWWWWWWWWWWWWWWWSSS   SWSSN  SSS
                    SSSS                   SSSSSSSSW SWWWWWWWWWWWWWWWWWWWSSSSSSWS2  sSSS
                      S                        fSSW 7SWWWWWWWWWWWWWWWWWWW2SSSNSSSSSSSSNJ
                                             SSSWSS SSWWWWWWWWWWWWWWWWWWWSS     SNSSS
                                             fSSWWS  SWWWWWWWWWWWWWWWWWWSSS
                                              NSSWSN SSWWWWWWWWWWWWWWSSSS
                                               SSWWS  SSWWWWWWWWWSSSNSN
                                sox            jS2WSS  SSWWWWWWSSNs
                              SSSSSSSSSSSSo  x SSWWWSS  SSWWWSSS
                              SSWWSSSSSSSSSSSSSSSWWWSS  NSSWWSS
                             SSWSSSS        fSSSSSSSSS   SSWWSs
                            SSW2SSS                      sSWWS
                            SSSSSj                      NSSSSS
                           oNSN                       SSSSNSS
                                                    SSSSS
                                                  SNSS
                                                SSSS
                                               SSWWSSS
                                               SSWSSW
                                               WSSS
                                                 SSSSS
                                                 SSSS
                                                  SS

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