BGI - Borland Graphics Interface for Rust

A modern Rust port of the classic Borland Graphics Interface (BGI) with extensible backends.

Features

• Full BGI API compatibility with modern Rust ergonomics
• Multiple graphics backends: MiniFB (visual), Pixel Buffer (headless/testing), PGM output
• Multiple graphics drivers: CGA, MCGA, EGA, VGA, IBM 8514, Hercules, AT&T 400, PC 3270
• Double-buffering support with active/visual page management
• Keyboard and mouse input handling
• 16-color EGA/VGA palette with RGB color support
• Line styles and fill patterns with custom bit patterns
• Viewport clipping and coordinate management
• Zero-cost abstractions with BatchDrawer and compile-time optimizations
• Modern Rust: Edition 2024, MSRV 1.90

Quick Start

use bgi::*;

fn main() {
    let mut driver = DETECT;
    let mut mode = VGAHI;
    
    initgraph(&mut driver, &mut mode, "");
    
    if graphresult() != GraphResult::Ok {
        eprintln!("Graphics initialization failed!");
        return;
    }
    
    setcolor(Color::RED);
    circle(320, 240, 50);
    
    outtextxy(250, 300, "Press any key to exit");
    
    getch();
    closegraph();
}

Run with visual output:

cargo run --example simple --features visual-backend

Examples

# Basic drawing demo
cargo run --example simple --features visual-backend

# Mandelbrot set visualization
cargo run --example mandelbrot --features visual-backend

# Interactive demonstration with mouse/keyboard
cargo run --example interactive_demo --features visual-backend

# BGI compatibility test
cargo run --example compatibility --features visual-backend

# Batch rendering (optimized)
cargo run --example mandelbrot_batched --features visual-backend

API Overview

Graphics Initialization

• initgraph() / closegraph() - Initialize and close graphics mode
• detectgraph() - Auto-detect best graphics driver/mode
• getgraphmode() / setgraphmode() - Get/set current mode
• graphresult() / grapherrormsg() - Error handling

Drawing Primitives

• line(), lineto(), linerel() - Line drawing
• circle() - Circle with Bresenham algorithm
• arc(), ellipse() - Arc and ellipse drawing
• rectangle() - Rectangle outline
• putpixel(), getpixel() - Pixel operations
• fillpoly() - Polygon fill (outline only)

Colors & Palettes

• setcolor(), getcolor() - Drawing color
• setbkcolor(), getbkcolor() - Background color
• setpalette(), getpalette() - Palette management
• setrgbpalette() - RGB palette entry
• 16 predefined colors: Color::BLACK, Color::WHITE, Color::RED, etc.

Line Styles & Fill

• setlinestyle() - Solid, dashed, dotted, dot-dashed, user-defined patterns
• getlinesettings() - Get current line style
• setfillstyle() - Fill pattern and color
• setfillpattern() - Custom 8x8 fill pattern
• setwritemode() - COPY_PUT, XOR_PUT, OR_PUT, AND_PUT, NOT_PUT

Viewports & Coordinates

• setviewport() / getviewport() - Clipping region
• clearviewport() / cleardevice() - Screen clearing
• getmaxx(), getmaxy() - Screen dimensions
• moveto(), moverel(), getx(), gety() - Cursor control

Text (Partial)

• outtextxy() - Display text at position (stub)
• settextstyle(), settextjustify() - Text configuration
• textwidth(), textheight() - Text measurement

Input Handling

• getch(), kbhit() - Keyboard input
• getmouse(), ismouseclick() - Mouse state
• mousex(), mousey() - Mouse position
• setmouse(), clearmouseclick() - Mouse control

Pages & Buffering

• setactivepage() / getactivepage() - Draw to off-screen page
• setvisualpage() / getvisualpage() - Display page

Utilities

• delay() - Millisecond delay
• is_headless() - Check if running without display
• set_batch_mode(), refresh() - Batch rendering optimization

Optimizations

• BatchDrawer - Batch multiple draw operations
• DrawingPool - Pre-allocated buffers for repeated operations
• PatternShape<N> - Compile-time optimized regular polygons

Supported Graphics Modes

Driver	Mode	Resolution	Colors
CGA	CGAC0-CGAC3	320x200	4
CGA	CGAHI	640x200	2
MCGA	MCGAC0-MCGAC3	320x200	256
MCGA	MCGAMED	640x200	256
MCGA	MCGAHI	640x480	256
EGA	EGALO	640x200	16
EGA	EGAHI	640x350	16
VGA	VGALO	640x200	16
VGA	VGAMED	640x350	16
VGA	VGAHI	640x480	16

Backends

MiniFB Backend (visual-backend feature)

Cross-platform windowing using minifb. Provides real-time visual output with keyboard and mouse support.

Pixel Buffer Backend (default)

Headless backend for testing and offline rendering. Stores pixels in memory without display output.

PGM Backend (pgm-backend feature)

Outputs to Portable GrayMap format files for image export.

Implementation Status

Complete:

• Graphics initialization and mode management
• All drawing primitives (line, circle, arc, ellipse, rectangle)
• Color and palette management
• Line styles with custom patterns
• Viewports and coordinate systems
• Keyboard and mouse input
• Page flipping / double buffering

Partial:

• Text rendering (outtextxy is a stub)
• Fill patterns (outline only for polygons)
• Image operations (getimage/putimage exist but limited)

Not Yet Implemented:

• Flood fill (floodfill)
• Filled shapes (bar, fillellipse, sector, pieslice)
• Font file loading

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.