How to have black edge on custom plane

Hi im new to JME and I started working on a project about origami.
I used Plane object created by vertices that define the plane to represent paper:

Vector3f [] vertices = new Vector3f[4];
vertices[0] = new Vector3f(-3,0,0);
vertices[1] = new Vector3f(-3,0,3);
vertices[2] = new Vector3f(3,0,3);
vertices[3] = new Vector3f(3,0,0);
Plane f = new Plane(vertices);
Geometry front = new Geometry(“Box”, f);

I need a material to represent the visual of the paper.
I tried the unshaded material but it won’t show when two paper overlap that that is two pieces of paper. I tried using CartoonEdge Filter to highlight edge but it only highlight the outside of shapes(basically when i put two piece of paper side by side together, i appears to be 1). I tried making my own paper shade but i do know how the fragment shader realize to colour the edge differently. So I need help. Please help.

If the mesh has texture coordinates, you can apply a texture to the unshaded material to discolor the edges.

However, if I wanted to visualize origami, I’d probably use a shaded material with directional lighting, mesh normals, and shadows.

you could optionally use com.jme3.scene.shape.Quad which is already a mesh with texture coords (as suggested in the previous post), ready to be sent to geometry.

i believe com.jme3.math.Plane is a mathematical construct and as such, has no edges.

one could also create a duplicate mesh and use setMode(Mesh.Mode.Lines) to show only the edges of the duplicate mesh with a different colored unshaded material… at the cost of doubling the resource “weight” of each mesh used this way.
this method may not be suitable if there is no intention of marking folds as edges also.

And posterize the colors to increase the effect.