Camera Demo Example

Side-scrolling platformer-style demo that showcases Camera2D (smoothing and horizontal bounds), parallax background layers, KinematicActor movement with tile-based ground and one-way platforms (StaticActor, collision layers), and directional iris scene transitions between two scenes. The world is wider than the screen so the camera follows the player.

Requirements (build flags)

• PIXELROOT32_ENABLE_SCENE_ARENA
• PIXELROOT32_ENABLE_SCENE_TRANSITIONS (enabled by default in PlatformDefaults.h)

Additional engine features (physics actors, tilemaps) follow defaults from PlatformDefaults.h. See platformio.ini in this folder for native and esp32dev presets.

The scene expects extern pixelroot32::core::Engine engine (see src/platforms/native.h / esp32_dev.h and main.cpp).

Platforms

Environment	Notes
native	SDL2 window, 240×240 logical size. Transitions work via RGB565 pixel buffer path.
esp32dev	ST7789 TFT 240×240, TFT_eSPI-style pin defines in platformio.ini. Transitions work via 8bpp sprite buffer path.

The engine version or Git branch is set in lib_deps in platformio.ini.

Controls

• Left / Right — move (buttons 2 and 3 in InputManager order).
• Jump — button 4 (edge-triggered after release so hold does not spam jump).

Scenes

The demo contains two scenes with identical gameplay but different color palettes:

	CameraDemoScene (Scene 1)	CameraDemoScene2 (Scene 2)
Parallax far	DarkBlue	Teal
Parallax mid	DarkGreen	Orange
Tilemap color	Brown	Gold

Both scenes share the same tilemap layout (ground + 3 platforms), player physics, and camera follow.

Scene Transitions

• Scene 1 → Scene 2: Iris transition closes from the right edge, opens from the left edge. Triggered when the player reaches the rightmost end of the level.
• Scene 2 → Scene 1: Iris transition closes from the left edge, opens from the right edge. Triggered when the player reaches the leftmost edge (position ≤ 0).

The iris effect uses directional centers (irisOutCx/Cy, irisInCx/Cy) stored in SceneManager and re-applied after each TransitionEffect::init() call.

Transition Rendering Paths

The engine automatically selects the correct rendering path:

• ESP32 (8bpp): TransitionEffect::apply() operates on the TFT_eSPI sprite buffer (palette-indexed).
• Native/SDL2 (RGB565): TransitionEffect::applyRGB565() operates directly on the SDL2 pixel buffer when getSpriteBuffer() returns nullptr.

Features

• Camera2D: follow target, bounds, locked vertical scroll in this demo
• Parallax layers + tilemap strip for ground/platforms
• KinematicActor player cube (PlayerCube), gravity and one-way platform collision masks
• Scene arena for stable entity storage (fixed-size array, no heap allocation)
• Directional iris transitions between two scenes with opposite center directions
• TransitionEffect: Fade (palette LUT) and Iris (circle wipe), zero-allocation

File Structure

src/
├── CameraDemoScene.h/.cpp     — Scene 1 (platformer, transitions to Scene 2)
├── CameraDemoScene2.h/.cpp    — Scene 2 (identical gameplay, different colors, back to Scene 1)
├── PlayerCube.h/.cpp          — KinematicActor with gravity/jump/movement
├── GameConstants.h            — Tile size, player dimensions, physics constants
├── GameLayers.h               — Collision layer bitmasks
└── platforms/
    ├── native.h               — SDL2 engine wiring
    └── esp32_dev.h            — ESP32 engine wiring

Documentation links

• Graphics — Camera2D
• Graphics — TransitionEffect
• Core — Scene / entities
• Core — SceneManager transitions
• Physics — kinematic & static actors
• Architecture

Build

Run from examples/camera:

pio run -e native
pio run -e esp32dev

Upload (ESP32)

pio run -e esp32dev --target upload

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Source code: https://github.com/PixelRoot32-Game-Engine/PixelRoot32-Game-Engine/tree/main/examples/camera