Hands-on notes on Android development, embedded systems, firmware, and hardware DIY, written from my own projects.https://chaosgoo.com/en/https://chaosgoo.com/en/how-to-pass-adsense-from-rejection-to-approval/https://chaosgoo.com/en/how-to-pass-adsense-from-rejection-to-approval/After 13 account applications and 10 site review submissions, my blog finally got Google AdSense approval. Here is what I tried, fixed, and got wrong.Thu, 01 Oct 2026 10:06:32 GMThttps://chaosgoo.com/en/media3-video-watermark/https://chaosgoo.com/en/media3-video-watermark/Adding video watermarks on Android with Media3 and comparing the resulting app size and implementation trade-offs with FFmpeg.Sun, 09 Aug 2026 11:30:00 GMThttps://chaosgoo.com/en/android-run-executable-binary-bypass/https://chaosgoo.com/en/android-run-executable-binary-bypass/Running native executables on Android 10 and later through the jniLibs extraction mechanism while accounting for W^X restrictions and platform constraints.Fri, 12 Jun 2026 20:30:00 GMThttps://chaosgoo.com/en/pixelcompass-a-better-minecraft-compass-irl/https://chaosgoo.com/en/pixelcompass-a-better-minecraft-compass-irl/Rebuilding the Minecraft compass in real life (Project: PixelCompass). Hardware is fully open-source. This new iteration downgrades the MCU to the budget-friendly WCH CH592F to drastically cut cost and power consumption, optimizes LED diffusion, and introduces a driverless USB web dashboard for easy configuration. Includes complete bill of materials, assembly guide, and troubleshooting.Wed, 20 May 2026 20:39:32 GMThttps://chaosgoo.com/en/android-boot-animation-clock/https://chaosgoo.com/en/android-boot-animation-clock/How Android BootAnimation's drawClock and drawText functions draw time text by selecting glyphs from a font atlas.Fri, 15 May 2026 00:12:00 GMThttps://chaosgoo.com/en/android-boot-animation-shine-logo/https://chaosgoo.com/en/android-boot-animation-shine-logo/Tracing Android BootAnimation's logo shine effect in AOSP and recreating it as an interactive Canvas demo with adjustable parameters.Tue, 12 May 2026 22:34:00 GMThttps://chaosgoo.com/en/05-extract-3mf-and-cpp-opengl-rendering/https://chaosgoo.com/en/05-extract-3mf-and-cpp-opengl-rendering/Extracting geometry with lib3mf in C++, packing vertex data, calculating area-weighted smooth normals, and rendering a 3MF model with OpenGL shaders and VBOs.Mon, 06 Apr 2026 22:20:00 GMThttps://chaosgoo.com/en/04-flutter-texture-cpp-opengl-architecture/https://chaosgoo.com/en/04-flutter-texture-cpp-opengl-architecture/Connecting Flutter Texture to Android EGL and native C++ through JNI to build an OpenGL rendering pipeline without adding a PlatformView hierarchy.Tue, 24 Mar 2026 16:56:33 GMThttps://chaosgoo.com/en/03-parse-3mf-info-in-flutter/https://chaosgoo.com/en/03-parse-3mf-info-in-flutter/Reading 3MF model metadata in Flutter through lib3mf and FFI, from asset file handling and cross-platform logging to iterating model objects on Android.Sat, 14 Mar 2026 01:22:22 GMThttps://chaosgoo.com/en/02-flutter-ffi-plugin-android-integration/https://chaosgoo.com/en/02-flutter-ffi-plugin-android-integration/Creating a Flutter FFI plugin for lib3mf, configuring the Android NDK, redirecting std::cout to Logcat, and handling Android 15's 16 KB page size requirements.Tue, 10 Mar 2026 10:00:00 GMThttps://chaosgoo.com/en/01-compile-lib3mf-and-examples/https://chaosgoo.com/en/01-compile-lib3mf-and-examples/Building lib3mf from source with CMake, running its examples, and exploring the 3MF core specification and extensions before integrating it into Flutter.Tue, 03 Mar 2026 09:20:37 GMThttps://chaosgoo.com/en/flutter-deep-dive-platform-view-and-method-channel/https://chaosgoo.com/en/flutter-deep-dive-platform-view-and-method-channel/Embedding Android native views in Flutter through PlatformView and using MethodChannel for two-way communication, with notes on layout constraints.Thu, 26 Feb 2026 11:00:00 GMThttps://chaosgoo.com/en/spherical-geometry-distance-bearing-derivation/https://chaosgoo.com/en/spherical-geometry-distance-bearing-derivation/Deriving great-circle distance from 3D Cartesian coordinates, examining short-distance precision loss, and obtaining the numerically stable haversine formula.Thu, 19 Feb 2026 01:09:27 GMThttps://chaosgoo.com/en/pagespeed-optimization-journey/https://chaosgoo.com/en/pagespeed-optimization-journey/Documenting the complete process of analyzing and optimizing a Hexo blog using PageSpeed Insights. Mobile score improved from 53 to 97, and desktop score reached a perfect 100.Fri, 13 Feb 2026 10:33:00 GMThttps://chaosgoo.com/en/make-remote-streaming-on-m5stack-cardputer/https://chaosgoo.com/en/make-remote-streaming-on-m5stack-cardputer/Five years later, I return to the ESP32 streaming challenge with the M5Stack Cardputer. Moving from a breadboard setup to hard-core H.264 decoding in your palm.Sun, 08 Feb 2026 22:55:41 GMThttps://chaosgoo.com/en/android-lvgl-style-border/https://chaosgoo.com/en/android-lvgl-style-border/Implementing an LVGL-style border on Android by changing FrameLayout measurement and using PorterDuffXfermode to draw rounded borders that occupy layout space.Wed, 04 Feb 2026 13:13:02 GMThttps://chaosgoo.com/en/esp-idf-embed-txtfiles-tricks/https://chaosgoo.com/en/esp-idf-embed-txtfiles-tricks/How ESP-IDF's EMBED_TXTFILES works, including CMake resource embedding, read-only flash data, linker symbols, and TLS certificate handling.Sun, 04 Jan 2026 12:12:44 GMThttps://chaosgoo.com/en/ditherpunk-the-art-of-dithering-2-esp32/https://chaosgoo.com/en/ditherpunk-the-art-of-dithering-2-esp32/Porting dithering algorithms to an ESP32 monochrome display, with gamma lookup tables, an ST7305 driver, and Bayer, Atkinson, and blue-noise comparisons.Tue, 30 Dec 2025 13:38:00 GMThttps://chaosgoo.com/en/ditherpunk-the-art-of-dithering/https://chaosgoo.com/en/ditherpunk-the-art-of-dithering/Compare Bayer, Floyd-Steinberg and Atkinson dithering in your browser, toggle linear luminance, and download black/white PNGs. Images stay on your device.Fri, 02 Oct 2026 19:40:00 GMThttps://chaosgoo.com/en/esp32-pppos-4g-modem/https://chaosgoo.com/en/esp32-pppos-4g-modem/Connecting ESP32-C3 and Air780EG through ESP-IDF PPPoS: UART wiring, esp_modem setup, IP events, and troubleshooting power, flow control and APN.Fri, 02 Oct 2026 19:40:00 GMThttps://chaosgoo.com/en/ch58x-dma-spi-ws2812-driver/https://chaosgoo.com/en/ch58x-dma-spi-ws2812-driver/Driving WS2812 LEDs with SPI and DMA on CH592F and CH582, using four-bit expansion and GRB encoding to avoid blocking the CPU during BLE operation.Mon, 01 Dec 2025 11:20:00 GMThttps://chaosgoo.com/en/hexo-seo-gsc-canonical-301/https://chaosgoo.com/en/hexo-seo-gsc-canonical-301/Fixing duplicate-page and canonical URL problems in Google Search Console for a Hexo blog using 301 redirects, robots.txt, and configuration changes.Fri, 21 Nov 2025 13:27:47 GMThttps://chaosgoo.com/en/claude-code%E5%88%9D%E4%BD%93%E9%AA%8C/https://chaosgoo.com/en/claude-code%E5%88%9D%E4%BD%93%E9%AA%8C/Trying Claude Code on an Android serial monitor project, from API and CLI setup to letting the coding assistant implement a feature on its own.Sun, 16 Nov 2025 23:39:44 GMThttps://chaosgoo.com/en/real-life-healthpin/https://chaosgoo.com/en/real-life-healthpin/Building a CS2-inspired electronic health badge with WCH CH592F, BLE HID, and GSI, covering PCB design, power management, and a custom device script.Thu, 20 Nov 2025 18:45:00 GMThttps://chaosgoo.com/en/2025-google-play-%E4%B8%AA%E4%BA%BA%E5%BC%80%E5%8F%91%E8%80%85%E4%B8%8A%E6%9E%B6%E8%AE%B0%E5%BD%95/https://chaosgoo.com/en/2025-google-play-%E4%B8%AA%E4%BA%BA%E5%BC%80%E5%8F%91%E8%80%85%E4%B8%8A%E6%9E%B6%E8%AE%B0%E5%BD%95/My 2025 Google Play release: $25 registration, a 12-tester closed test lasting 14 days, production access, and Firebase / AdMob privacy disclosures.Fri, 02 Oct 2026 19:40:00 GMThttps://chaosgoo.com/en/android-gl14-surfaceview-zero-copy-texture-sharing/https://chaosgoo.com/en/android-gl14-surfaceview-zero-copy-texture-sharing/Forking AOSP's GLSurfaceView into GL14SurfaceView to share GPU textures between EGL14 contexts and render to multiple views without CPU copies.Thu, 10 Apr 2025 21:10:30 GMThttps://chaosgoo.com/en/dwm3001cdk-spi-ws2812-driver/https://chaosgoo.com/en/dwm3001cdk-spi-ws2812-driver/Driving a WS2812 RGB LED over SPI using the nRF52833 on a DWM3001CDK development board.Sun, 12 Jan 2025 15:05:37 GMThttps://chaosgoo.com/en/minecraft-compass-irl/https://chaosgoo.com/en/minecraft-compass-irl/Building and using MCompass, an ESP32-C3 and GPS-based Minecraft compass with lodestone targeting, overshoot animation, firmware setup, and a bill of materials.Sat, 14 Dec 2024 00:00:00 GMThttps://chaosgoo.com/en/friday-ink/https://chaosgoo.com/en/friday-ink/Building Friday Ink, a CH582F e-paper clock with approximately 3μA sleep current, including display drivers, Rust firmware, and power switching.Sat, 29 Nov 2025 11:16:59 GMThttps://chaosgoo.com/en/add-your-xiaomi-yeelight-monitor-light-bar-to-homekit-with-esp32-c3/https://chaosgoo.com/en/add-your-xiaomi-yeelight-monitor-light-bar-to-homekit-with-esp32-c3/Adding a Xiaomi Yeelight monitor light bar to HomeKit by building an ESP32-C3 replacement controller, with teardown and pin measurements.Sat, 29 Nov 2025 10:42:01 GMThttps://chaosgoo.com/en/the-death-of-onresume-declarative-ui-lifecycle/https://chaosgoo.com/en/the-death-of-onresume-declarative-ui-lifecycle/Why declarative UI frameworks use explicit lifecycle subscriptions instead of component-level onResume, with examples from Flutter and Compose.Tue, 02 Jan 2024 00:01:19 GMThttps://chaosgoo.com/en/lenovo-r720-keyboard-matrix/https://chaosgoo.com/en/lenovo-r720-keyboard-matrix/Mapping a Lenovo R720 laptop keyboard matrix and adapting it with Raspberry Pi Pico, QMK, and a 74HC165 I/O expander for a KVM project.Sun, 13 Nov 2022 20:00:00 GMThttps://chaosgoo.com/en/esp32-advanced-dev-tips/https://chaosgoo.com/en/esp32-advanced-dev-tips/Four ESP32 development notes: asynchronous HTTP, keeping PWM active during light sleep, GIF playback, and OTA updates for SPIFFS resources.Tue, 20 Sep 2022 22:45:22 GMThttps://chaosgoo.com/en/parallel-lcd-vs-spi-lcd/https://chaosgoo.com/en/parallel-lcd-vs-spi-lcd/Comparing 60 MHz SPI and 8-bit parallel LCD performance on ESP32 using TFT_eSPI and LVGL to examine rendering and bus throughput limits.Sat, 29 Nov 2025 02:46:19 GMThttps://chaosgoo.com/en/lvgl-freetype-and-esp32-2/https://chaosgoo.com/en/lvgl-freetype-and-esp32-2/Loading variable fonts on ESP32 with FreeType and LVGL, configuring PlatformIO libraries, and managing memory with LV_FREETYPE_SBIT_CACHE.Mon, 03 Jan 2022 12:40:53 GMThttps://chaosgoo.com/en/lvgl-freetype-and-esp32/https://chaosgoo.com/en/lvgl-freetype-and-esp32/Moving an LVGL variable-font demo from a desktop simulator to ESP32, configuring FreeType, and driving an ST7789 display with dynamic font weights.Sat, 18 Dec 2021 21:47:07 GMThttps://chaosgoo.com/en/freetype-and-lvgl/https://chaosgoo.com/en/freetype-and-lvgl/Getting started with variable fonts and dynamic font weights in LVGL using FreeType, with MIUI and Material You as examples of the effect.Sun, 12 Dec 2021 17:09:13 GMThttps://chaosgoo.com/en/diy-stackoverflow-3-key-macro-keyboard-with-atmega32u4/https://chaosgoo.com/en/diy-stackoverflow-3-key-macro-keyboard-with-atmega32u4/Recreating Stack Overflow's April Fools' three-key macro keyboard with ATmega32U4 USB HID, a KiCad PCB, and Arduino keyboard shortcuts.Thu, 18 Dec 2025 20:10:00 GMThttps://chaosgoo.com/en/esp32-display-remote-jpg/https://chaosgoo.com/en/esp32-display-remote-jpg/Displaying remote JPG images on ESP32 over HTTP, with AsyncTCP chunk handling, Content-Length parsing, and onData callbacks.Tue, 25 Nov 2025 00:07:26 GMThttps://chaosgoo.com/en/esp32-streaming/https://chaosgoo.com/en/esp32-streaming/Streaming PC frames to ESP32 using Python MSS capture, OpenCV JPEG encoding, a custom TCP protocol, and TFT_eSPI with DMA display rendering.Thu, 27 Nov 2025 09:40:31 GMThttps://chaosgoo.com/en/stattrak/https://chaosgoo.com/en/stattrak/Building a physical CS:GO StatTrak counter, from OLED and MAX7219 display experiments to an HDSP2072 display, ATmega32U4 board, and custom enclosure.Sun, 18 Jan 2026 00:00:00 GMThttps://chaosgoo.com/en/make-a-tiny-pixel-screen/https://chaosgoo.com/en/make-a-tiny-pixel-screen/Building a tiny desktop pixel display with a custom WS2812 2020 LED board, AWatrix-based firmware, a diffuser, and a WeMos D1 mini.Sat, 29 Nov 2025 10:52:57 GMThttps://chaosgoo.com/en/homekit-esp32-control-light-part_one/https://chaosgoo.com/en/homekit-esp32-control-light-part_one/Combining an ESP32 HomeKit LED demo with MCPWM servo control to operate a physical light switch through Siri without modifying its wiring.Sun, 28 Jun 2026 12:50:00 GMThttps://chaosgoo.com/en/homekit-esp32-control-light-part_two/https://chaosgoo.com/en/homekit-esp32-control-light-part_two/Setting up ESP32 HomeKit development in Windows WSL, building and flashing esp-homekit-demo, and accessing a serial device through ttyS3.Sun, 10 May 2020 17:03:25 GMThttps://chaosgoo.com/en/pro-micro/https://chaosgoo.com/en/pro-micro/Recovering a Pro Micro that disconnects or is not detected, investigating SoftwareSerial conflicts, and entering the bootloader by resetting RST and GND twice.Sun, 18 Jan 2026 00:00:00 GMThttps://chaosgoo.com/en/imgtag%E6%95%99%E7%A8%8B/https://chaosgoo.com/en/imgtag%E6%95%99%E7%A8%8B/Training a YOLO-Tiny object detection model with Keras-YOLO3 and Python, including CFG filter counts, weight conversion, and train.py configuration.Sun, 16 Jun 2019 22:25:47 GMThttps://chaosgoo.com/en/ffmpeg-on-android/https://chaosgoo.com/en/ffmpeg-on-android/Building FFmpeg shared libraries with the Android NDK, comparing decoding options, and troubleshooting version names and MinGW/MSYS cross-compilation.Sat, 03 Feb 2018 21:01:08 GMT