public override void IssueDrawCall_BackStencil(LightWithStencilShadow light, CommandBuffer commands)
 {
     var renderer = GetComponent<Renderer>();
     int n = m_stencil_materials.Length;
     for (int i = 0; i < n; ++i)
     {
         commands.DrawRenderer(renderer, m_stencil_materials[i], i, 1);
     }
 }
        void EnableKeywords(LightWithStencilShadow light)
        {
            switch(light.m_type)
            {
                case LightWithStencilShadow.Type.Point:
                    m_stencil_materials[0].EnableKeyword("PROJECTION_POINT");
                    break;
                case LightWithStencilShadow.Type.Line:
                    m_stencil_materials[0].EnableKeyword("PROJECTION_LINE");
                    break;
            }

            if (light.m_inverse)
            {
                m_stencil_materials[0].EnableKeyword("ENABLE_INVERSE");
            }
            else
            {
                m_stencil_materials[0].DisableKeyword("ENABLE_INVERSE");
            }
        }