Hello World Example

Minimal PixelRoot32 project: UILabel text, button polling through InputManager, and a background color that cycles every few frames. Intended as the smallest “engine boots → scene draws → input works” check.

Requirements (build flags)

No special PIXELROOT32_ENABLE_* flags beyond what lib/platformio.ini / defaults pull in. Resolution is set with PHYSICAL_DISPLAY_WIDTH, PHYSICAL_DISPLAY_HEIGHT (128×128) in platformio.ini.

The scene uses extern pixelroot32::core::Engine engine from your platform file (src/platforms/native.h or esp32_dev.h) — same pattern as other examples.

Platforms

Environment	Display
native	SDL2, 128×128 logical size
esp32dev	ST7735 128×128 (GreenTab3 profile), SPI pins in platformio.ini: MOSI 23, SCLK 18, DC 2, RST 4, CS -1
esp32s3	ST7735 128×128 (GreenTab3 profile), SPI pins in platformio.ini: MOSI 12, MISO 14, SCLK 13, DC 10, RST 11, CS 9

⚠️ Note for ESP32-S3: The env:esp32s3 uses Arduino Core 2.0.14 as a workaround for DMA freeze issues (see espressif/arduino-esp32#9618). This is configured in platformio.ini via platform_packages.

Controls

• D-pad / face buttons — any press is shown in the second label (checkButtonPress() in HelloWorldScene.cpp).
• Background advances on a fixed frame interval (COLOR_CHANGE_INTERVAL).

Features

• Scene lifecycle (init / update / draw)
• UILabel and Renderer text/color APIs
• InputManager button bitmask

Documentation links

• Core API
• UI API
• Graphics / Renderer

Build

From examples/hello_world:

pio run -e native
pio run -e esp32dev
pio run -e esp32_s3

Upload (ESP32)

pio run -e esp32dev --target upload