private static RenderMode GetBlendMode(GltfFormat.VrmMaterial material)
        {
            if (material.IsKeywordEnabled(MToonUtils.KeyAlphaTestOn))
            {
                return(RenderMode.Cutout);
            }
            else if (material.IsKeywordEnabled(MToonUtils.KeyAlphaBlendOn))
            {
                switch (material.GetInt(MToonUtils.PropZWrite))
                {
                case MToonUtils.EnabledIntValue:
                    return(RenderMode.TransparentWithZWrite);

                case MToonUtils.DisabledIntValue:
                    return(RenderMode.Transparent);

                default:
                    throw new ArgumentException("Invalid ZWrite Int Value.");
                }
            }
            else
            {
                return(RenderMode.Opaque);
            }
        }
        private static OutlineColorMode GetOutlineColorMode(GltfFormat.VrmMaterial material)
        {
            if (material.IsKeywordEnabled(MToonUtils.KeyOutlineColorFixed))
            {
                return(OutlineColorMode.FixedColor);
            }
            if (material.IsKeywordEnabled(MToonUtils.KeyOutlineColorMixed))
            {
                return(OutlineColorMode.MixedLighting);
            }

            return(OutlineColorMode.FixedColor);
        }
        private static OutlineWidthMode GetOutlineWidthMode(GltfFormat.VrmMaterial material)
        {
            if (material.IsKeywordEnabled(MToonUtils.KeyOutlineWidthWorld))
            {
                return(OutlineWidthMode.WorldCoordinates);
            }
            if (material.IsKeywordEnabled(MToonUtils.KeyOutlineWidthScreen))
            {
                return(OutlineWidthMode.ScreenCoordinates);
            }

            return(OutlineWidthMode.None);
        }