Boot Animation

EFI

Customize the animated boot screen displayed by the UEFI DXE driver during the 5-second delay before chainloading Windows.

Overview

The EFI driver displays a custom animated boot screen using the UEFI Graphics Output Protocol (GOP). Animation frames are pre-converted at build time and embedded in the EFI binary for maximum performance.

Technical Details

• Format: BGRA32 (matches GOP PixelBlueGreenRedReserved8BitPerColor)
• Pre-converted: No runtime GIF decoding, frames stored as raw pixels
• Display: Centered on screen, loops for 5 seconds
• Fallback: Text-only display if GOP unavailable
• Recommended: Max 256x256 resolution, 10-15 fps

Converting a GIF Animation

Use the provided Python tool to convert a GIF to the C header format:

Convert GIF

# Install requirements
pip install Pillow

# Convert GIF to C header
python efi/tools/gif_to_header.py your_animation.gif -o efi/DioProcessEfi/Animation.h

# Rebuild EFI driver
cd efi
build -a X64 -t VS2022 -p DioProcessEfi/DioProcessEfi.dsc -b RELEASE

Animation.h Format

Animation.h (generated)

#ifndef ANIMATION_H
#define ANIMATION_H

#define ANIMATION_WIDTH  128
#define ANIMATION_HEIGHT 128
#define ANIMATION_FRAME_COUNT 12
#define ANIMATION_FRAME_DELAY_MS 83  // ~12 fps

// Frame data: BGRA32 format, row-major order
static const UINT8 AnimationFrame0[] = {
    0x00, 0x00, 0x00, 0xFF,  // Pixel 0: BGRA
    0x8B, 0x5C, 0xF6, 0xFF,  // Pixel 1: Violet
    // ... (WIDTH * HEIGHT * 4 bytes per frame)
};

static const UINT8 AnimationFrame1[] = { /* ... */ };
// ... more frames

static const UINT8* AnimationFrames[] = {
    AnimationFrame0,
    AnimationFrame1,
    // ... all frames
};

#endif

Graphics Implementation

Graphics.c (excerpt)

EFI_STATUS PlayAnimation(VOID) {
    EFI_GRAPHICS_OUTPUT_PROTOCOL *Gop;
    EFI_STATUS Status;
    
    // 1. Locate GOP protocol
    Status = gBS->LocateProtocol(
        &gEfiGraphicsOutputProtocolGuid,
        NULL,
        (VOID**)&Gop
    );
    if (EFI_ERROR(Status)) {
        // Fallback to text mode
        return ShowTextBanner();
    }
    
    // 2. Get screen dimensions
    UINTN ScreenWidth = Gop->Mode->Info->HorizontalResolution;
    UINTN ScreenHeight = Gop->Mode->Info->VerticalResolution;
    
    // 3. Calculate centered position
    UINTN X = (ScreenWidth - ANIMATION_WIDTH) / 2;
    UINTN Y = (ScreenHeight - ANIMATION_HEIGHT) / 2;
    
    // 4. Animation loop (5 seconds)
    UINTN TotalFrames = (5000 / ANIMATION_FRAME_DELAY_MS);
    for (UINTN i = 0; i < TotalFrames; i++) {
        UINTN FrameIndex = i % ANIMATION_FRAME_COUNT;
        
        // 5. Blit frame to screen
        Gop->Blt(
            Gop,
            (EFI_GRAPHICS_OUTPUT_BLT_PIXEL*)AnimationFrames[FrameIndex],
            EfiBltBufferToVideo,
            0, 0,           // Source X, Y
            X, Y,           // Dest X, Y
            ANIMATION_WIDTH,
            ANIMATION_HEIGHT,
            0               // Delta (row stride)
        );
        
        // 6. Wait for next frame
        gBS->Stall(ANIMATION_FRAME_DELAY_MS * 1000);  // microseconds
    }
    
    return EFI_SUCCESS;
}

Creating Custom Animations

Tips for creating effective boot animations:

• Keep it small — Large animations increase EFI binary size
• Simple loops — 8-16 frames is usually sufficient
• Use transparency wisely — Alpha channel is preserved
• Test on real hardware — Some UEFI implementations have limitations

Alternative: Matrix Animation

The repo includes tools to generate Matrix-style falling code animation:

# Generate Matrix animation
python efi/tools/gen_matrix_animation.py -o efi/DioProcessEfi/Animation.h

# Preview in console
python efi/tools/preview_matrix.py

Default Placeholder

The default Animation.h contains a simple 2-frame blinking violet square that demonstrates the animation system without adding significant binary size.