Physics Demo Example

Interactive physics sandbox: KinematicActor player, RigidActor boxes and circles (AABB and circle shape), StaticActor floors/walls, sensors, and ActorTouchController for dragging/spawning on touch-capable builds.

When PIXELROOT32_ENABLE_UI_SYSTEM is on (default in PlatformDefaults.h), esp32cyd builds also expose touch UI: UITouchButton (full reset), UITouchSlider (dynamic spawn count), UITouchCheckbox, and horizontal/vertical layouts — see PhysicsDemoScene.h.

Requirements (build flags)

• PIXELROOT32_ENABLE_SCENE_ARENA — pre-allocated box/circle pools and arena-safe add/remove when the slider changes.
• PIXELROOT32_ENABLE_TOUCH=1 — set for native and esp32cyd in platformio.ini so touch APIs compile and mouse/touch can drive the demo.
• esp32cyd additionally enables PIXELROOT32_ENABLE_DEBUG_OVERLAY, PIXELROOT32_DEBUG_MODE, ILI9341 240×320, and XPT2046 touch (many tuning -Ds in platformio.ini).

See platformio.ini for native, esp32dev, esp32cyd.

Platforms

Environment	Display / input
native	SDL2, 240×240; touch flag enables the same code paths with simulated touch
esp32dev	ST7789 240×240 (no PIXELROOT32_ENABLE_TOUCH in this preset — use keyboard/GPIO per your platforms/esp32_dev.h)
esp32cyd	ILI9341 240×320 + XPT2046 resistive touch

Controls / interaction

• Move player — bind your InputManager layout to the kinematic actor (see scene update / player handling).
• Touch (native + CYD) — processTouchEvents / onUnconsumedTouchEvent and ActorTouchController for world interaction; CYD also gets on-screen UI widgets when PIXELROOT32_ENABLE_UI_SYSTEM is true.

Features

• Rigid dynamics (restitution, friction), circle vs AABB collision shape
• Static scenery with bounce flag on walls
• Sensor-style regions (as wired in the demo scene)
• Optional touch HUD (slider adjusts how many boxes/circles are registered without re-running init() from scratch)

Documentation links

• Physics API
• Input API
• UI API
• Core — Scene

Build

From examples/physics:

pio run -e native
pio run -e esp32dev
pio run -e esp32cyd

Upload (ESP32)

pio run -e esp32dev --target upload
pio run -e esp32cyd --target upload