Project 5: ANSI Color Renderer
Extend Project 4’s terminal to interpret SGR (Select Graphic Rendition) sequences and render colored output, using a simple terminal graphics library (ncurses or direct ANSI to host terminal).
Quick Reference
| Attribute | Value |
|---|---|
| Primary Language | C |
| Alternative Languages | Rust, Go |
| Difficulty | Level 2: Intermediate (The Developer) |
| Time Estimate | 1 week |
| Knowledge Area | ANSI / Color Handling / Rendering |
| Tooling | Color Renderer |
| Prerequisites | Project 2, Project 4 |
What You Will Build
Extend Project 4’s terminal to interpret SGR (Select Graphic Rendition) sequences and render colored output, using a simple terminal graphics library (ncurses or direct ANSI to host terminal).
Why It Matters
This project builds core skills that appear repeatedly in real-world systems and tooling.
Core Challenges
- SGR parsing → Multiple parameters in one sequence
- Color model understanding → 16-color, 256-color, 24-bit RGB
- State management → Track current foreground, background, attributes
- Default handling → What “reset” means, default colors
- Attribute stacking → Bold + underline + color combined
Key Concepts
- SGR Sequences: ANSI Escape Codes Gist - fnky
- 256-Color Mode: 256 Color Chart
- True Color: 24-bit ANSI Colors
Real-World Outcome
$ ls --color | ./color_terminal
# Now you see colors!
$ ./color_terminal
$ htop
# htop displays with full color support!
$ echo -e "\x1b[1;31;44mBold Red on Blue\x1b[0m"
# Renders correctly!
Implementation Guide
- Reproduce the simplest happy-path scenario.
- Build the smallest working version of the core feature.
- Add input validation and error handling.
- Add instrumentation/logging to confirm behavior.
- Refactor into clean modules with tests.
Milestones
- Milestone 1: Minimal working program that runs end-to-end.
- Milestone 2: Correct outputs for typical inputs.
- Milestone 3: Robust handling of edge cases.
- Milestone 4: Clean structure and documented usage.
Validation Checklist
- Output matches the real-world outcome example
- Handles invalid inputs safely
- Provides clear errors and exit codes
- Repeatable results across runs
References
- Main guide:
TERMINAL_EMULATOR_DEEP_DIVE_PROJECTS.md - “Computer Graphics from Scratch” by Gabriel Gambetta