Add splash screen icon and build-time SVG-to-RGB565 generator

- pyxis-icon.svg: Pyxis constellation icon (3 stars with connecting lines)
- generate_splash.py: PlatformIO pre-build script that renders the SVG to
  a 160x160 RGB565 PROGMEM header (SplashImage.h) using cairosvg + Pillow
- .gitignore: Exclude generated SplashImage.h
- platformio.ini: Add generate_splash.py to both build environments

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitignore

@@ -2,3 +2,4 @@
 .vscode/
 *.pyc
 docs/flasher/firmware/
+lib/tdeck_ui/Hardware/TDeck/SplashImage.h

generate_splash.py

@@ -0,0 +1,98 @@
+"""
+PlatformIO pre-build script: Convert pyxis-icon.svg to RGB565 PROGMEM header.
+
+Generates lib/tdeck_ui/Hardware/TDeck/SplashImage.h containing a 160x160
+pixel splash image as a PROGMEM byte array. Skips regeneration if the
+header is already newer than the source SVG.
+
+Requires: cairosvg, Pillow (gracefully skips if not installed)
+"""
+
+Import("env")
+
+import os
+import struct
+
+ICON_SIZE = 160
+SVG_FILE = "pyxis-icon.svg"
+HEADER_FILE = os.path.join("lib", "tdeck_ui", "Hardware", "TDeck", "SplashImage.h")
+BG_COLOR = (0x1D, 0x1A, 0x1E)  # #1D1A1E — matches fill_screen in show_splash()
+
+
+def rgb888_to_rgb565(r, g, b):
+    """Convert 8-bit RGB to 16-bit RGB565 (big-endian bytes)."""
+    rgb565 = ((r & 0xF8) << 8) | ((g & 0xFC) << 3) | (b >> 3)
+    return struct.pack(">H", rgb565)
+
+
+def should_regenerate(svg_path, header_path):
+    """Return True if the header needs regeneration."""
+    if not os.path.exists(header_path):
+        return True
+    return os.path.getmtime(svg_path) > os.path.getmtime(header_path)
+
+
+project_dir = env.get("PROJECT_DIR", os.getcwd())
+svg_path = os.path.join(project_dir, SVG_FILE)
+header_path = os.path.join(project_dir, HEADER_FILE)
+
+if not os.path.exists(svg_path):
+    print(f"[generate_splash] {SVG_FILE} not found, skipping splash generation")
+elif not should_regenerate(svg_path, header_path):
+    print(f"[generate_splash] {HEADER_FILE} is up-to-date, skipping")
+else:
+    try:
+        import cairosvg
+        from PIL import Image
+        import io
+    except ImportError as e:
+        print(f"[generate_splash] Missing dependency ({e}), skipping splash generation")
+        print(f"[generate_splash] Install with: pip install cairosvg Pillow")
+    else:
+        print(f"[generate_splash] Rendering {SVG_FILE} -> {HEADER_FILE} ({ICON_SIZE}x{ICON_SIZE} RGB565)")
+
+        # Render SVG to PNG at target size
+        png_data = cairosvg.svg2png(
+            url=svg_path,
+            output_width=ICON_SIZE,
+            output_height=ICON_SIZE,
+        )
+
+        img = Image.open(io.BytesIO(png_data)).convert("RGBA")
+
+        # Composite onto background color (handles transparency)
+        bg = Image.new("RGBA", (ICON_SIZE, ICON_SIZE), BG_COLOR + (255,))
+        bg.paste(img, (0, 0), img)
+        img = bg.convert("RGB")
+
+        # Convert to RGB565 big-endian byte array
+        pixels = list(img.getdata())
+        rgb565_bytes = bytearray()
+        for r, g, b in pixels:
+            rgb565_bytes.extend(rgb888_to_rgb565(r, g, b))
+
+        # Write C header
+        os.makedirs(os.path.dirname(header_path), exist_ok=True)
+
+        with open(header_path, "w") as f:
+            f.write("// AUTO-GENERATED by generate_splash.py — do not edit\n")
+            f.write("#ifndef SPLASH_IMAGE_H\n")
+            f.write("#define SPLASH_IMAGE_H\n\n")
+            f.write("#include <Arduino.h>\n\n")
+            f.write(f"#define SPLASH_WIDTH  {ICON_SIZE}\n")
+            f.write(f"#define SPLASH_HEIGHT {ICON_SIZE}\n")
+            f.write(f"#define HAS_SPLASH_IMAGE 1\n\n")
+            f.write(f"// {ICON_SIZE}x{ICON_SIZE} RGB565 big-endian ({len(rgb565_bytes)} bytes)\n")
+            f.write("static const uint8_t PROGMEM splash_image[] = {\n")
+
+            # Write bytes, 16 per line
+            for i in range(0, len(rgb565_bytes), 16):
+                chunk = rgb565_bytes[i:i+16]
+                hex_str = ", ".join(f"0x{b:02X}" for b in chunk)
+                trailing = "," if i + 16 < len(rgb565_bytes) else ""
+                f.write(f"    {hex_str}{trailing}\n")
+
+            f.write("};\n\n")
+            f.write("#endif // SPLASH_IMAGE_H\n")
+
+        print(f"[generate_splash] Generated {len(rgb565_bytes)} bytes ({ICON_SIZE}x{ICON_SIZE} RGB565)")

platformio.ini

@@ -1,6 +1,8 @@
 ; T-Deck environment using Bluedroid BLE stack (fallback, uses more RAM)
 [env:tdeck-bluedroid]
-extra_scripts = pre:version.py
+extra_scripts =
+    pre:version.py
+    pre:generate_splash.py
 platform = espressif32
 board = esp32-s3-devkitc-1
 framework = arduino
@@ -79,6 +81,7 @@ build_flags =
 [env:tdeck]
 extra_scripts =
     pre:version.py
+    pre:generate_splash.py
     pre:patch_nimble.py
 platform = espressif32
 board = esp32-s3-devkitc-1

pyxis-icon.svg

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="utf-8"?>
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512">
+  <defs>
+    <radialGradient id="starGlow">
+      <stop offset="0" style="stop-color:#FFFFFF;stop-opacity:0.8"/>
+      <stop offset="0.5" style="stop-color:#FFFFFF;stop-opacity:0.3"/>
+      <stop offset="1" style="stop-color:#FFFFFF;stop-opacity:0"/>
+    </radialGradient>
+  </defs>
+  <circle cx="256" cy="256" r="256" fill="#1D1A1E"/>
+  <g transform="matrix(1, 0, 0, 1, 17.99218, -6.964715)">
+    <path stroke="#FFFFFF" stroke-width="4.5" fill="none" stroke-linecap="round" opacity="0.6" d="M 245.377 322.844 L 181.759 90.3"/>
+    <path stroke="#FFFFFF" stroke-width="4.5" fill="none" stroke-linecap="round" opacity="0.6" d="M 273.819 413.359 L 245.377 322.844"/>
+    <circle cx="181.759" cy="90.3" r="20" fill="url(#starGlow)"/>
+    <circle cx="181.759" cy="90.3" r="8" fill="#FFFFFF"/>
+    <circle cx="245.377" cy="322.844" r="26" fill="url(#starGlow)"/>
+    <circle cx="245.377" cy="322.844" r="10" fill="#FFFFFF"/>
+    <circle cx="273.819" cy="413.359" r="22" fill="url(#starGlow)"/>
+    <circle cx="273.819" cy="413.359" r="9" fill="#FFFFFF"/>
+  </g>
+</svg>