static void Export_Emission(Material m, TextureExportManager textureManager, glTFMaterial material)
        {
            if (m.IsKeywordEnabled("_EMISSION") == false)
            {
                return;
            }

            if (m.HasProperty("_EmissionColor"))
            {
                var color = m.GetColor("_EmissionColor");
                if (color.maxColorComponent > 1)
                {
                    color /= color.maxColorComponent;
                }
                material.emissiveFactor = new float[] { color.r, color.g, color.b };
            }

            if (m.HasProperty("_EmissionMap"))
            {
                var index = textureManager.CopyAndGetIndex(m.GetTexture("_EmissionMap"), RenderTextureReadWrite.sRGB);
                if (index != -1)
                {
                    material.emissiveTexture = new glTFMaterialEmissiveTextureInfo()
                    {
                        index = index,
                    };
                }
            }
        }
        static void Export_Color(Material m, TextureExportManager textureManager, glTFMaterial material)
        {
            if (m.HasProperty("_Color"))
            {
                material.pbrMetallicRoughness.baseColorFactor = m.color.ToArray();
            }

            if (m.HasProperty("_MainTex"))
            {
                var index = textureManager.CopyAndGetIndex(m.GetTexture("_MainTex"), RenderTextureReadWrite.sRGB);
                if (index != -1)
                {
                    material.pbrMetallicRoughness.baseColorTexture = new glTFMaterialBaseColorTextureInfo()
                    {
                        index = index,
                    };
                }
            }
        }