Rendering transparent meshes in LibGDX

Rendering transparent meshes in LibGDX

Building open this tutorial -
https://code.google.com/p/libgdx/wiki/ProjectionViewportCamera I have
constructed a class for generating polygon meshes. But i cannot figure out
how to render semi transparency, even though the mesh in the tutorial
takes a color object with an alpha channel.
I am rendering with squareMesh.render(GL10.GL_TRIANGLE_STRIP, 0, 4); This
is the code used for initializing the mesh
if (squareMesh == null) {
squareMesh = new Mesh(true, 4, 4,
new VertexAttribute(Usage.Position, 3, "a_position"),
new VertexAttribute(Usage.ColorPacked, 4, "a_color"));
squareMesh.setVertices(new float[] {
-0.5f, -0.5f, 0, Color.toFloatBits(128, 0, 0, 255),
0.5f, -0.5f, 0, Color.toFloatBits(192, 0, 0, 255),
-0.5f, 0.5f, 0, Color.toFloatBits(192, 0, 0, 255),
0.5f, 0.5f, 0, Color.toFloatBits(255, 0, 0, 255) });
squareMesh.setIndices(new short[] { 0, 1, 2, 3});
}