Creating and Using Meshes

Meshes are built from geometry classes (primitives), which define their vertex data. Each geometry can be reused across multiple meshes, and passed directly when creating a new mesh.

🔹 Example: Creating a circular terrain

terrainGeometry = new UeCircleGeometry(500);
terrain = new UeMesh(terrainGeometry, new UeMeshStandardMaterial(), { z: 50 });
// The third argument is an optional struct of properties to apply to the mesh (such as position, rotation, etc.).

🧱 Available Geometry Primitives

These are the built-in geometry types available:

• UeBoxGeometry
• UeLineGeometry
• UeLineSegmentsGeometry
• UePlaneGeometry
• UeCircleGeometry
• UeSphereGeometry
• UePyramidGeometry
• UeConeGeometry
• UeCylinderGeometry
• UeArrowGeometry
• UeTorusGeometry
• UeIcosahedronGeometry
• UeOctahedronGeometry

You can instantiate them with relevant parameters (e.g., radius, width, height), and they automatically generate the vertex buffers needed for rendering.

🛠️ Creating Custom Geometry

If you want full control, create a UeGeometry with a custom UeVertexFormat. In this example, we are going to create a triangle geometry:

Step 1: Define Vertex Format (optional)

var format = new UeVertexFormat().position().normal().uv().color().build();

Step 2: Create Geometry

var position = [
    -0.5, -0.5, 0,
     0.5, -0.5, 0,
     0.0,  0.5, 0
];

var normal = [
    0, 0, 1,
    0, 0, 1,
    0, 0, 1
];

var uv = [
    0, 0,
    1, 0,
    0.5, 1
];

var color = [
    c_white, 1,
    c_white, 1,
    c_white, 1
];

var geometry = new UeGeometry({ position, normal, uv, color, format });

🧠 The geometries also support custom attributes defined in the format by passing them as flat arrays.

🎨 Adding a Material

You can assign a material to the mesh by including it in the creation properties:

var material = new UeMaterial({
  color: make_color_rgb(200, 200, 255),
  transparent: true
});

var sphere = new UeMesh(new UeSphereGeometry(), material, { 
  position: vec3_create(0, 0, 0) 
});

✅ Note: You can still modify the mesh's transform, material, or geometry after creation if needed.