Apollo

Apollo is an experimental text editor written from scratch in C for Windows.

The project is focused on editor architecture, rendering, text layout, and systems programming rather than wrapping an existing GUI text control. It is not production-ready yet, but it already includes the core pieces of a custom editor stack: file-backed buffers, editing commands, multi-cursor state, fuzzy search, font rasterization, table-driven theming, and a D3D11 renderer backend.

Screenshots

Status

Apollo is under active development and should be treated as a personal systems project, not a finished daily editor.

Current priorities:

• Stabilize the buffer/edit model
• Improve UTF-8 handling
• Replace the flat text buffer with a more scalable representation
• Expand automated tests
• Polish the public build/demo workflow

Features

• From-scratch C codebase with a small platform abstraction layer
• Win32 windowing, input, file dialogs, clipboard, timing, and filesystem support
• D3D11-based renderer abstraction
• Font loading, TTF rasterization, glyph atlas pages, and raster cache
• Text layout and viewport caching for visible editor lines
• File-backed buffers with save-state tracking
• Cursor movement, selection, clipboard operations, undo/redo, and multi-cursor state
• Fuzzy search providers for commands, buffers, files, and unsaved buffers
• Table-based configuration format used for theme data
• Toggleable editor UI elements such as status bar and gutter

Architecture

Apollo is organized into small modules under src/:

• base/ - core types, strings, arenas, math, colors, paths, logging, profiling
• os/ - Windows platform layer for windows, input, memory, files, time, and dialogs
• renderer/ - GPU resource model and D3D11 backend
• fonts/ - TTF loading/rasterization and glyph cache
• text/ - text layout, render runs, and viewport cache
• buffer/ - buffer identity, file loading/saving, revisions, line indexing, undo data
• edit/ - editor commands, cursor state, selections, clipboard, undo/redo integration
• views/ - editor layout, scrolling, gutter/status UI, and active view state
• search/ - fuzzy-search UI and provider model
• table/ and theme/ - table parser/runtime and theme loading

See docs/architecture.md for more detail.

Building

Requirements:

• Windows
• clang-cl
• Windows SDK

From the repository root:

build.bat

The build script currently produces apollo.exe in the repository root. Generated executables, debug symbols, Visual Studio metadata, and common build output directories are ignored by Git.

Running

After building:

apollo.exe

The editor currently opens the guided demo file under data/demo/demo.txt by default.

Current Limitations

• Windows-only
• Debug/development build workflow
• The buffer is currently a flat byte buffer with full line rescans
• UTF-8 support exists in parts of the stack but is not complete everywhere
• Automated test coverage is still growing
• Some systems still use fixed-size global arrays while the architecture settles
• Large-file editing is not a primary goal yet

Roadmap

• Replace the flat buffer with a piece table, gap buffer, or similar editor-friendly representation
• Add focused tests for buffer operations, undo/redo, search ranking, and text movement
• Improve Unicode correctness and text navigation
• Expand syntax highlighting through the plugin/lexer path
• Improve save/reload conflict handling
• Add a short demo recording for the public repository

License

Apollo is licensed under the terms in LICENSE.