Tutorial: Adding a New Game Object

Register a new ObjectType, map its sprite icon, and place it in a level.

Step 1 — Add the ObjectType Enum Value

File: include/GalaxyEggbert/def/ObjectType.hpp

// After ObjectType203:
ObjectType204 = 204,   // MyNewObject

Step 2 — Add an Icon Mapping in Decor::GetIcon()

File: src/GalaxyEggbert/Game/Decor.cpp

case ObjectType204:
    // element.png icon 42 — static
    return 42;

Icon indices reference the element.png sprite sheet (600×1740 px, 60×60 tiles, 10 cols × 29 rows, 290 icons). Choose an appropriate icon that visually represents your object. If the object animates, return baseIcon + (animPhase / frameDivisor) % frameCount.

Step 3 — Add Contact Behaviour in Decor::Update()

In the per-object contact check inside Decor::Update(), handle your object type:

if (obj.type == ObjectType204 && distance < 0.85f) {
    // e.g., treat it as a collectible:
    collected_++;
    obj.active = false;
    obj.node->Remove();
}

Step 4 — Place the Object in a Level

In a mobile-eggbert .txt level file, add a MoveObject entry:

MoveObject
   numObject=204
   posStart=50.0 1.0 50.0
   posEnd=50.0 1.0 50.0
   speed=0.0
   ...

Or call Decor::PlaceObject() directly from the demo world builder:

decor_->PlaceObject(ObjectType204, Vector3(50, 1, 50));

Step 5 — Build and Test

cmake --build cmake-build-debug --parallel
cd cmake-build-debug/bin && ./GalaxyEggbert

Navigate Blupi to the object. Verify it renders with the correct sprite and triggers the expected behaviour on contact.