EN/CityGML-Tutorial/chapter-2:-Building/LOD3.md

@@ -102,7 +102,8 @@ To demonstrate the process of creating a simple CityGML 2.0 LOD3 building model
 
 In order to make a conversion from Sketchup to CityGML 2.0 LOD3 using FME, the modeling process in Sketchup must meet some layering requirements:
 
-- All the edges must be kept in Layer0.
+- All the edges must be kept in Layer0 (see [Chapter 2.1: Building LOD1](https://transfer.hft-stuttgart.de/gitlab/coors/3d-stadtmodelle/-/wikis/EN/CityGML-Tutorial/chapter%202:%20Building/LOD1)).
+
 - New layers must be defined using the following abbreviation name for CityGML semantic elements:
 
   1. ws → WallSurface
@@ -117,18 +118,33 @@ In order to make a conversion from Sketchup to CityGML 2.0 LOD3 using FME, the m
 - All polygons must be classified to its respective SketchUp layers based on above classification.
 - Parent-child elements are separated with underscore ( _ ) and elements from their ids with dash ( – ). For example, a layer "ws-1_d-1"  interprets to “doors belonging to wall surface 1". In case of doors or windows, the parent boundary surface should hold all the individual elements. For example, if a wall surface (ws-1) has 2 doors and 3 windows, then the 2 doors should be put in a layer named ws-1_d-1 and the 3 windows in a layer named ws-1_w-1.
 
+<div align=center>
+
 **lod 3 model sketchup**  
 
+</div>
+
 A complete FME workbench along with sample input and output dataset modeled as LOD3 MultiSurface can be downloaded from **here**. The available FME workbench contains annotations for easy step by step understanding of the conversion process.
 
+<div align=center>
+
 **lod 3 FME workflow**  
 
->The SketchUp model is created using a local (cartesian)coordiante system. No coordiante trasnformation is done during its translation to CityGML as the purpose of this exercise is to demonstrate the conversion process. For 3D data reprojection, transformer 3D affiner can be used to define a coordinate transformation matrix. For defining a CRS, transformer coordinatesystemsetter or reprojector can be used. More info on working with coordinate systems in FME can be found from [here](https://community.safe.com/s/article/using-coordinate-systems-within-fme).
+</div>
+
+>The SketchUp model is created using a local (cartesian)coordiante system. No coordiante trasnformation is done during its translation to CityGML as the purpose of this exercise is to demonstrate the conversion process. For 3D data reprojection, transformer [3DAffiner](https://www.safe.com/transformers/3d-affiner/) can be used to define a coordinate transformation matrix. For defining a CRS, transformer [coordinatesystemsetter](https://www.safe.com/transformers/coordinate-system-setter/) or [reprojector](https://www.safe.com/transformers/reprojector/) can be used. More info on working with coordinate systems in FME can be found from [here](https://community.safe.com/s/article/using-coordinate-systems-within-fme).
+
+<div align=center>
+
+**lod 3 FME output in FZK** 
+
+</div>
 
-A CityGML 3.0 LOD3 building model of the above used example building can be downloaded from **here**. An automated CityGML2-to-CityGML3 convertor is used to convert the LOD3 building model from CityGML 2.0 to CityGML 3.0. 
+To correctly insert building solid either using [FME](https://gitlab.com/volkercoors/CiD4Sim/-/wikis/usefulTools/FME-Workbenches-(EN)) or a free [SolidInjector](https://github.com/tomeof/citygml-injector) please follow the [previous tutorial](https://transfer.hft-stuttgart.de/gitlab/coors/3d-stadtmodelle/-/wikis/EN/CityGML-Tutorial/chapter-2:-Building/LOD2). See [Chapter 2.2: Building LOD2](https://transfer.hft-stuttgart.de/gitlab/coors/3d-stadtmodelle/-/wikis/EN/CityGML-Tutorial/chapter%202:%20Building/LOD2).
 
-To correctly insert building solid either using [FME](https://gitlab.com/volkercoors/CiD4Sim/-/wikis/usefulTools/FME-Workbenches-(EN)) or a free [SolidInjector](https://github.com/tomeof/citygml-injector) please follow the [previous tutorial](https://transfer.hft-stuttgart.de/gitlab/coors/3d-stadtmodelle/-/wikis/EN/CityGML-Tutorial/chapter-2:-Building/LOD2).
+As an alternative to FME, free GEORES plugin for SketchUp can also be used to convert SketchUp models to CityGML 2.0 in LOD 0,1,2,3 and 4. More info on GEORES plugin can be found [here](https://github.com/GeoplexGIS/geores).
 
+A CityGML 3.0 LOD3 building model of the above used example building can be downloaded from **here**. An automated [CityGML2-to-CityGML3 convertor](https://github.com/tum-gis/citygml2-to-citygml3) is used to convert the LOD3 building model from CityGML 2.0 to CityGML 3.0.
 
 **Next Chapter** [Chapter 2.4: Appearance](https://transfer.hft-stuttgart.de/gitlab/coors/3d-stadtmodelle/-/wikis/EN/CityGML-Tutorial/chapter%202:%20Building/Appearance)