screenshot: simplify capture workflow

Author: mitander

.gitignore

@@ -0,0 +1,2 @@
+screenshot_raw.png
+Session.vim

screenshot.png

@@ -0,0 +1,102 @@
+from pathlib import Path
+
+from PIL import Image, ImageDraw, ImageFilter
+
+ROOT_DIR = Path(__file__).resolve().parent.parent
+BACKGROUND_SOURCE = ROOT_DIR / "scripts" / "assets" / "flume_glitch_bg.jpg"
+RAW_SCREENSHOT = ROOT_DIR / "screenshot_raw.png"
+BACKGROUND_OUTPUT = ROOT_DIR / "background.png"
+SCREENSHOT_OUTPUT = ROOT_DIR / "screenshot.png"
+
+MAX_WINDOW_WIDTH = 0.88
+MAX_WINDOW_HEIGHT = 0.86
+CORNER_RADIUS = 16
+SHADOW_PADDING = 10
+SHADOW_OFFSET_Y = 2
+SHADOW_COLOR = (12, 10, 18, 30)
+
+
+def crop_to_opaque_bounds(image):
+    alpha = image.split()[-1]
+    opaque_mask = alpha.point(lambda p: 255 if p == 255 else 0)
+    bounds = opaque_mask.getbbox()
+    return image.crop(bounds) if bounds else image
+
+
+def fit_inside(source_size, target_size):
+    source_width, source_height = source_size
+    max_width, max_height = target_size
+    source_ratio = source_width / source_height
+
+    width = max_width
+    height = int(width / source_ratio)
+
+    if height > max_height:
+        height = max_height
+        width = int(height * source_ratio)
+
+    return width, height
+
+
+def round_corners(image, radius):
+    mask = Image.new("L", image.size, 0)
+    draw = ImageDraw.Draw(mask)
+    draw.rounded_rectangle((0, 0, image.width, image.height), radius, fill=255)
+
+    rounded = Image.new("RGBA", image.size)
+    rounded.paste(image, (0, 0), mask=mask)
+    return rounded
+
+
+def make_shadow(size, radius):
+    width, height = size
+    shadow = Image.new(
+        "RGBA",
+        (width + SHADOW_PADDING * 2, height + SHADOW_PADDING * 2),
+        (0, 0, 0, 0),
+    )
+    draw = ImageDraw.Draw(shadow)
+    draw.rounded_rectangle(
+        (SHADOW_PADDING, SHADOW_PADDING, SHADOW_PADDING + width, SHADOW_PADDING + height),
+        radius,
+        fill=SHADOW_COLOR,
+    )
+    return shadow.filter(ImageFilter.GaussianBlur(2))
+
+
+def compose_header(background, window):
+    max_window_size = (
+        int(background.width * MAX_WINDOW_WIDTH),
+        int(background.height * MAX_WINDOW_HEIGHT),
+    )
+    window_size = fit_inside(window.size, max_window_size)
+    window = window.resize(window_size, Image.Resampling.LANCZOS)
+    window = round_corners(window, CORNER_RADIUS)
+    shadow = make_shadow(window_size, CORNER_RADIUS)
+
+    window_x = (background.width - window.width) // 2
+    window_y = (background.height - window.height) // 2
+    shadow_x = window_x - SHADOW_PADDING
+    shadow_y = window_y - SHADOW_PADDING + SHADOW_OFFSET_Y
+
+    background.alpha_composite(shadow, (shadow_x, shadow_y))
+    background.alpha_composite(window, (window_x, window_y))
+    return background
+
+
+def main():
+    if not RAW_SCREENSHOT.exists():
+        raise SystemExit(f"Missing {RAW_SCREENSHOT}. Run scripts/screenshot-window.sh first.")
+
+    background = Image.open(BACKGROUND_SOURCE).convert("RGBA")
+    window = Image.open(RAW_SCREENSHOT).convert("RGBA")
+    window = crop_to_opaque_bounds(window)
+
+    background.convert("RGB").save(BACKGROUND_OUTPUT, "PNG", optimize=True)
+    compose_header(background, window).convert("RGB").save(SCREENSHOT_OUTPUT, "PNG", optimize=True)
+
+    print(f"Saved {SCREENSHOT_OUTPUT}")
+
+
+if __name__ == "__main__":
+    main()

scripts/assets/flume_glitch_bg.jpg

@@ -1,88 +1,143 @@
 #!/bin/bash
+set -euo pipefail
 
-# Script to automatically spawn Ghostty with the Flume theme,
-# open Neovim with the sample file, position the cursor,
-# and take a screenshot of the window.
-
-# Ensure we are in the repository root
 cd "$(dirname "$0")/.."
 
-# Check if Ghostty is installed
-if ! osascript -e 'id of application "Ghostty"' &>/dev/null; then
-    echo "Error: Ghostty is not installed or not in Applications."
+GHOSTTY_COLUMNS=102
+GHOSTTY_ROWS=26
+GHOSTTY_FONT_SIZE=19
+GHOSTTY_PID=""
+INPUT_FILE=""
+
+fail() {
+    echo "Error: $*" >&2
     exit 1
-fi
-
-# Resolve absolute paths
-NVIM_PATH=$(command -v nvim)
-if [ -z "$NVIM_PATH" ]; then
-    NVIM_PATH="nvim"
-fi
-
-EXAMPLE_DIR="$(pwd)/examples"
-FILE_NAME="flume.zig"
-WORKING_DIR="$EXAMPLE_DIR"
-
-# Ghostty is launched via macOS `open`, so the terminal process may not inherit
-# the PATH from the shell that ran this script. Capture the user's login-shell
-# PATH and pass it explicitly so Neovim can find tools such as zig and zls.
-TERMINAL_PATH=$(/bin/zsh -lc 'print -r -- "$PATH"')
-if [ -z "$TERMINAL_PATH" ]; then
-    TERMINAL_PATH="$PATH"
-fi
-
-# Avoid Ghostty's macOS "Allow Ghostty to execute ...?" prompt by not using
-# -e/--command. Instead, start the normal login shell and send the nvim command
-# as startup input. Leave the temp file in /tmp long enough for Ghostty to read it.
-INPUT_FILE=$(mktemp "${TMPDIR:-/tmp}/flume-screenshot-input.XXXXXX")
-printf '%q %q %q %q %q\n' \
-    "$NVIM_PATH" \
-    "+18" \
-    "+normal! w" \
-    "+lua vim.defer_fn(function() vim.o.autochdir = false; pcall(vim.cmd, 'lcd %:p:h'); pcall(vim.cmd, 'Gitsigns detach') end, 500)" \
-    "$FILE_NAME" >"$INPUT_FILE"
-
-echo "Opening Ghostty with the Flume theme and screenshot settings..."
-open -na Ghostty.app --args \
-    --window-save-state=never \
-    --quit-after-last-window-closed=true \
-    --theme=flume \
-    --font-size=19 \
-    --window-width=102 \
-    --window-height=28 \
-    --window-padding-x=16 \
-    --window-padding-y=16 \
-    --working-directory="$WORKING_DIR" \
-    --env="PATH=$TERMINAL_PATH" \
-    --input="path:$INPUT_FILE"
-
-# Give Ghostty and Neovim time to load LSP/Tree-sitter and draw
+}
+
+cleanup() {
+    if [ -n "$GHOSTTY_PID" ] && kill -0 "$GHOSTTY_PID" &>/dev/null; then
+        echo "Closing Ghostty..."
+        kill "$GHOSTTY_PID" &>/dev/null || true
+    fi
+
+    if [ -n "$INPUT_FILE" ]; then
+        rm -f "$INPUT_FILE"
+    fi
+}
+
+screen_recording_allowed() {
+    local probe
+    probe=$(mktemp "${TMPDIR:-/tmp}/flume-screenshot-probe.XXXXXX.png")
+
+    if screencapture -x -R 0,0,1,1 "$probe" &>/dev/null && [ -s "$probe" ]; then
+        rm -f "$probe"
+        return 0
+    fi
+
+    rm -f "$probe"
+    return 1
+}
+
+require_screen_recording() {
+    if screen_recording_allowed; then
+        return
+    fi
+
+    echo "macOS denied Screen Recording permission for this terminal."
+    echo "Grant permission, quit/reopen the terminal, then retry."
+    echo ""
+    echo "System Settings -> Privacy & Security -> Screen Recording"
+    echo ""
+    echo "sudo/password cannot grant this macOS privacy permission."
+    open "x-apple.systempreferences:com.apple.preference.security?Privacy_ScreenCapture" &>/dev/null || true
+    exit 1
+}
+
+capture_ghostty_window() {
+    local err_file
+    err_file=$(mktemp "${TMPDIR:-/tmp}/flume-screenshot-error.XXXXXX")
+
+    echo ""
+    echo "=========================================================="
+    echo " ACTION REQUIRED: click the Ghostty window with the camera."
+    echo "=========================================================="
+    echo ""
+
+    if screencapture -o -w screenshot_raw.png 2>"$err_file" && [ -s screenshot_raw.png ]; then
+        rm -f "$err_file"
+        return 0
+    fi
+
+    cat "$err_file" >&2
+    rm -f "$err_file" screenshot_raw.png
+
+    echo "Retrying with screen-backed window capture. Click Ghostty again."
+    screencapture -i -W -S -o screenshot_raw.png && [ -s screenshot_raw.png ]
+}
+
+launch_ghostty() {
+    local nvim_bin terminal_path example_dir input_cmd ghostty_app ghostty_bin
+
+    nvim_bin=$(command -v nvim || true)
+    if [ -z "$nvim_bin" ]; then
+        nvim_bin="nvim"
+    fi
+
+    terminal_path=$(/bin/zsh -lc 'print -r -- "$PATH"')
+    if [ -z "$terminal_path" ]; then
+        terminal_path="$PATH"
+    fi
+
+    example_dir="$(pwd)/examples"
+    INPUT_FILE=$(mktemp "${TMPDIR:-/tmp}/flume-screenshot-input.XXXXXX")
+    input_cmd="+lua vim.defer_fn(function() vim.o.autochdir = false; pcall(vim.cmd, 'lcd %:p:h'); pcall(vim.cmd, 'Gitsigns detach') end, 500)"
+
+    printf '%q %q %q %q %q\n' \
+        "$nvim_bin" \
+        "+18" \
+        "+normal! w" \
+        "$input_cmd" \
+        "flume.zig" >"$INPUT_FILE"
+
+    ghostty_app=$(osascript -e 'POSIX path of (path to application "Ghostty")')
+    ghostty_bin="${ghostty_app}Contents/MacOS/ghostty"
+
+    echo "Opening Ghostty with the Flume theme and screenshot settings..."
+    "$ghostty_bin" \
+        --window-save-state=never \
+        --quit-after-last-window-closed=true \
+        --theme=flume \
+        --font-size="$GHOSTTY_FONT_SIZE" \
+        --window-width="$GHOSTTY_COLUMNS" \
+        --window-height="$GHOSTTY_ROWS" \
+        --window-padding-x=16 \
+        --window-padding-y=16 \
+        --working-directory="$example_dir" \
+        --env="PATH=$terminal_path" \
+        --input="path:$INPUT_FILE" &
+    GHOSTTY_PID=$!
+    disown "$GHOSTTY_PID" 2>/dev/null || true
+}
+
+trap cleanup EXIT
+trap 'exit 130' INT
+trap 'exit 143' TERM
+
+osascript -e 'id of application "Ghostty"' &>/dev/null || fail "Ghostty is not installed or not in Applications."
+
+require_screen_recording
+launch_ghostty
+
+rm -f screenshot_raw.png
+
 echo "Waiting for window to render..."
-sleep 2.5
-
-# Bring Ghostty to front and capture its window ID
-WINDOW_ID=$(osascript -e '
-tell application "Ghostty"
-    activate
-    try
-        return id of window 1
-    on error
-        return ""
-    end try
-end tell')
-
-if [ -n "$WINDOW_ID" ]; then
-    echo "Capturing Ghostty window ID $WINDOW_ID..."
-    # Capture only the window, omitting the drop shadow (-o)
-    screencapture -o -l "$WINDOW_ID" screenshot.png
-    echo "Screenshot successfully saved to screenshot.png"
-    
-    # Gracefully close the Ghostty window
-    osascript -e '
-    tell application "Ghostty"
-        close window 1
-    end tell'
-else
-    echo "Error: Could not retrieve Ghostty window ID. Please take screenshot manually."
-fi
+sleep 1.0
+osascript -e 'tell application "Ghostty" to activate'
+
+capture_ghostty_window || fail "Capture cancelled or failed."
+
+cleanup
+trap - EXIT
 
+python3 "$(dirname "$0")/compose_header.py"
+echo "Updated screenshot.png"