Returns the type of this shader. If the type was declared in the source using a shader type token, it will have been loaded from it. Else this returns null and it must be set manually using
{@link #setType(org.spout.renderer.api.gl.Shader.ShaderType)}.
Returns the type of this shader. If the type was declared in the source using a shader type token, it will have been loaded from it. Else this returns null and it must be set manually using {@link #setType(org.spout.renderer.api.gl.Shader.ShaderType)}.
@return The shader type, or null if not set