Grids & Deformation

Connected Grids

Use MeshGridGenerator2D.GenerateConnectedGrid() to build a connected triangle grid over a texture.

var texture = Texture2D.LoadFromFile("character.png");

var grid = MeshGridGenerator2D.GenerateConnectedGrid(
    texture,
    new MeshGridOptions2D { Spacing = 64 });

The generator clamps spacing to a practical range and creates shared vertices along cell boundaries.

Mask-Guided Grids

Pass an IMeshMask2D when you want diagonal choices to better follow a visible shape while keeping the grid connected.

var mask = MeshMask2D.FromPredicate(point =>
    alphaMask.IsOpaqueAt(point.X, point.Y));

var grid = MeshGridGenerator2D.GenerateConnectedGrid(
    texture,
    new MeshGridOptions2D { Spacing = 64 },
    mask);

You can also pass a Func<Vector2, bool> directly:

var grid = MeshGridGenerator2D.GenerateConnectedGrid(
    texture,
    point => alphaMask.IsOpaqueAt(point.X, point.Y),
    new MeshGridOptions2D { Spacing = 64 });

Alpha-Map Masks

Use MeshMask2D.FromAlphaMap() when your app already decoded image pixels and has one alpha byte per pixel. The alpha data is row-major, and stride defaults to width.

var mask = MeshMask2D.FromAlphaMap(
    alpha: alphaBytes,
    width: imageWidth,
    height: imageHeight,
    threshold: 8);

Pass copy: false when you own the alpha buffer lifetime and want to avoid copying it:

var mask = MeshMask2D.FromAlphaMap(alphaBytes, width, height, threshold: 8, copy: false);

The core library still does not decode full image pixels. Decode image data in your UI/game layer, then adapt the alpha channel into IMeshMask2D with this helper.

Masked Contour Grids

Use GenerateMaskedContourGrid() when you want mesh faces only around the masked shape.

var contour = MeshGridGenerator2D.GenerateMaskedContourGrid(
    texture,
    mask,
    new MeshGridOptions2D { Spacing = 48 });

This is useful for overlays, picking, previews, or visualizing the visible alpha region of a sprite.

Deformers

IMeshDeformer2D lets you calculate deformed positions without changing the original mesh unless you explicitly apply the result.

public sealed class WaveDeformer : IMeshDeformer2D
{
    public void DeformInto(Mesh2D mesh, Span<Vector2> target)
    {
        for (var i = 0; i < mesh.Vertices.Count; i++)
        {
            var position = mesh.Vertices[i].Position;
            position.Y += MathF.Sin(position.X * 0.04f) * 8f;
            target[i] = position;
        }
    }
}

Built-in reference deformers include:

Type	Use
VertexOffsetDeformer2D	Offset selected vertices.
RadialDragDeformer2D	Drag vertices with a smooth radial falloff.

var drag = new RadialDragDeformer2D { Radius = 180f };
drag.SetDrag(origin, offset);

grid.ApplyDeformer(drag);

ApplyDeformer() commits deformed positions back into the mesh.