/// <summary>
/// Load initial resources.
/// </summary>
public virtual void LoadResources()
{
// - Loads essential shaders
ShaderManager.LoadShader <DefaultShader>();
var Rectangle = VertexManager.Alloc(4);
Rectangle[0] = new VertexData(new Vector3(-0.5F, -0.5F, 0F), Color4.Black);
Rectangle[1] = new VertexData(new Vector3(0.5F, -0.5F, 0F), Color4.Black);
Rectangle[2] = new VertexData(new Vector3(0.5F, 0.5F, 0F), Color4.Black);
Rectangle[3] = new VertexData(new Vector3(-0.5F, 0.5F, 0F), Color4.Black);
Rectangle.Invalidate();
var Indexes = IndexManager.Alloc(6);
Indexes[0] = 0;
Indexes[1] = 1;
Indexes[2] = 2;
Indexes[3] = 2;
Indexes[4] = 3;
Indexes[5] = 0;
Indexes.Invalidate();
}