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De-mystifying LiDAR data: 3D topography solutions for CAD and GIS users

Contents. Introduction to the companyOverview of how FME is used across the companyDetailed case study into of how FME enables Landmark to provide data solutionsKey benefits of using FME. Who are we?. ArchitectsEngineersSurveyorsEnvironmental ConsultantsDevelopersEstate agentsConveyancersLocal governmentUtility companies.

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De-mystifying LiDAR data: 3D topography solutions for CAD and GIS users

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    1. De-mystifying LiDAR data: 3D topography solutions for CAD and GIS users Matt Wills GIS Analyst 07th April 2011 Introduction: Name Role Title of presentation Next Slide: Introduction to presentationIntroduction: Name Role Title of presentation Next Slide: Introduction to presentation

    2. Contents Introduction to the company Overview of how FME is used across the company Detailed case study into of how FME enables Landmark to provide data solutions Key benefits of using FME Introduction Introduction to the company Overview of how FME is used across the company Detailed case study into of how FME enables Landmark to provide data solutions Key benefits of using FME Next Slide: Who are Landmark?Introduction Introduction to the company Overview of how FME is used across the company Detailed case study into of how FME enables Landmark to provide data solutions Key benefits of using FME Next Slide: Who are Landmark?

    3. Who are we? Architects Engineers Surveyors Environmental Consultants Developers Estate agents Conveyancers Local government Utility companies Who is Landmark? What is our market? Landmark was established in 1995 and provides a wide range of data and services relating to the property market. We provide information, data and services to a broad range of environmental and property professionals: Different fields Different requirements Range of skills/software Key Point - Data accuracy is important Next Slide: what do we do?Who is Landmark? What is our market? Landmark was established in 1995 and provides a wide range of data and services relating to the property market. We provide information, data and services to a broad range of environmental and property professionals: Different fields Different requirements Range of skills/software Key Point - Data accuracy is important Next Slide: what do we do?

    4. What do we do? Ordnance Survey Partner What do we do? Environmental data & reports (environmental professionals, conveyancers) Current and historic mapping (environmental professionals, conveyancers) Floor plans (for estate agents) Valuation information (for lenders) Geospatial solutions and managed services (Landmark Solutions) Partner Ordnance Survey company (re-selling OS Data) Next Slide: How do we use FME? What do we do? Environmental data & reports (environmental professionals, conveyancers) Current and historic mapping (environmental professionals, conveyancers) Floor plans (for estate agents) Valuation information (for lenders) Geospatial solutions and managed services (Landmark Solutions) Partner Ordnance Survey company (re-selling OS Data) Next Slide: How do we use FME?

    5. How do we use FME? How do we use FME? Key Point - FME used at many levels in the company: Bespoke data conversion/translation using FME Workbench (2009/2010) Loading and extracting data to/from corporate Oracle Spatial database Bulk data conversion using FME Server Next Slide: Take one specific example of how we use FME to provide data solutions for customers How do we use FME? Key Point - FME used at many levels in the company: Bespoke data conversion/translation using FME Workbench (2009/2010) Loading and extracting data to/from corporate Oracle Spatial database Bulk data conversion using FME Server Next Slide: Take one specific example of how we use FME to provide data solutions for customers

    6. Case Study - 3D topography solutions for CAD and GIS users Landmark are re-sellers of the Environment Agencys LiDAR Digital Elevation Data Case Study - Employing FME to provide 3D topography solutions for CAD and GIS users LIG are re-sellers of the Environment Agencys LiDAR Digital Elevation Data What is LiDAR? Stands for Light Detection and Ranging Similar to Radar, but uses beams of light (higher precision and weather independent) Used to quickly survey and produce detailed elevation models (aerial surveys of entire landscapes, or detailed localised surveys from ground mounted capture devices) Key Point high density, high accuracy data covering large extents The EA DEM covers large areas of the country (areas at risk of flooding) and is available in 2 forms: DSM DTM (explain differences) How is it Used? Range of uses flood modelling, civil engineering, planning, line of sight and visualisation Range of users from simple context to detailed site analysis Next Slide: What does the EA provide?Case Study - Employing FME to provide 3D topography solutions for CAD and GIS users LIG are re-sellers of the Environment Agencys LiDAR Digital Elevation Data What is LiDAR? Stands for Light Detection and Ranging Similar to Radar, but uses beams of light (higher precision and weather independent) Used to quickly survey and produce detailed elevation models (aerial surveys of entire landscapes, or detailed localised surveys from ground mounted capture devices) Key Point high density, high accuracy data covering large extents The EA DEM covers large areas of the country (areas at risk of flooding) and is available in 2 forms: DSM DTM (explain differences) How is it Used? Range of uses flood modelling, civil engineering, planning, line of sight and visualisation Range of users from simple context to detailed site analysis Next Slide: What does the EA provide?

    7. Case Study - 3D topography solutions for CAD and GIS users Case Study - Employing FME to provide 3D topography solutions for CAD and GIS users Key Point - Data only supplied in limited formats ASCII grid/Text points (JPEG does not actually contain any elevation information) ASCII grid is simply a regular array of height values (cell size varies with resolution) Key Point - Data only supplied in full NG tiles (500m or 1km depending on resolution) What are the problems/limitations associated with the data? File sizes ASCII/txt formats for use in GIS and dedicated 3D modelling software Limited use to CAD users in its native format Too many features for CAD to ingest easily (1km2 of data can easily contain 1,000,000 features) GIS users may require additional software/add-ons to get the full benefit from the data Next Slide: At this stage we didnt have the solution What can FME do? Case Study - Employing FME to provide 3D topography solutions for CAD and GIS users Key Point - Data only supplied in limited formats ASCII grid/Text points (JPEG does not actually contain any elevation information) ASCII grid is simply a regular array of height values (cell size varies with resolution) Key Point - Data only supplied in full NG tiles (500m or 1km depending on resolution) What are the problems/limitations associated with the data? File sizes ASCII/txt formats for use in GIS and dedicated 3D modelling software Limited use to CAD users in its native format Too many features for CAD to ingest easily (1km2 of data can easily contain 1,000,000 features) GIS users may require additional software/add-ons to get the full benefit from the data Next Slide: At this stage we didnt have the solution What can FME do?

    8. Case Study - 3D topography solutions for CAD and GIS users Case Study - Employing FME to provide 3D topography solutions for CAD and GIS users Merge data into a single file Clip data to site Customer only pays for the data they need Key Point particularly useful if site located across multiple tiles Next Slide: What other solutions can Landmark offer using FME?Case Study - Employing FME to provide 3D topography solutions for CAD and GIS users Merge data into a single file Clip data to site Customer only pays for the data they need Key Point particularly useful if site located across multiple tiles Next Slide: What other solutions can Landmark offer using FME?

    9. Case Study - 3D topography solutions for CAD and GIS users Using FME, Landmark are able to offer the following additional outputs: How do we use FME to provide solutions? In addition to the ASCII, TXT and JPEG formats, LIG can use FME to offer the following outputs: Points Contours TIN model 2D data suitable for both CAD & GIS users 3D data suitable for CAD users What is a TIN Model? TIN triangulated irregular network (or triangular inferred network) Efficient method of representing a surface (in this case a terrain) using triangles Derived 3D model for use in CAD packages (not just a straight format translation) CAD users can easily create surfaces from TIN/Contours Some CAD systems can ingest the source ASCII grid and generate a TIN, but this creates a pair of triangles for each cell in the source file as well as the following problems: Inflated file size Not clipped to site Problems around the edge of the tile FMEs SurfaceModeller produces an optimised TIN Model (and contours) suitable for CAD users Large triangles for flat areas, more & smaller triangles to represent complex terrain Because LIG are offering the facility to clip the ASCII data to an irregular shape, this facility is also offered for the AutoCAD dwg formats (TIN, Contours)How do we use FME to provide solutions? In addition to the ASCII, TXT and JPEG formats, LIG can use FME to offer the following outputs: Points Contours TIN model 2D data suitable for both CAD & GIS users 3D data suitable for CAD users What is a TIN Model? TIN triangulated irregular network (or triangular inferred network) Efficient method of representing a surface (in this case a terrain) using triangles Derived 3D model for use in CAD packages (not just a straight format translation) CAD users can easily create surfaces from TIN/Contours Some CAD systems can ingest the source ASCII grid and generate a TIN, but this creates a pair of triangles for each cell in the source file as well as the following problems: Inflated file size Not clipped to site Problems around the edge of the tile FMEs SurfaceModeller produces an optimised TIN Model (and contours) suitable for CAD users Large triangles for flat areas, more & smaller triangles to represent complex terrain Because LIG are offering the facility to clip the ASCII data to an irregular shape, this facility is also offered for the AutoCAD dwg formats (TIN, Contours)

    10. Case Study - 3D topography solutions for CAD and GIS users Clip the full TIN How do we use FME to provide solutions? Not straightforward Use the clipped ASCII grids as the input: SurfaceModeller has problems resolving the extents Clip the full TIN: Clipping extents are 2D Triangles on edge are pinned to zero elevation Triangles within site are 3D Clip using 3D clipping extents: Breaks the triangles on the edge No longer a Triangular network Next Slide: How do we use FME to provide these additional options? How do we use FME to provide solutions? Not straightforward Use the clipped ASCII grids as the input: SurfaceModeller has problems resolving the extents Clip the full TIN: Clipping extents are 2D Triangles on edge are pinned to zero elevation Triangles within site are 3D Clip using 3D clipping extents: Breaks the triangles on the edge No longer a Triangular network Next Slide: How do we use FME to provide these additional options?

    11. Case Study - 3D topography solutions for CAD and GIS users FME Transformer in detail Main transformer used to clip the source ASCII file and produce the clipped TIN and Contours 2D and 3D points created from the clipped ASCII using a separate FME workspace Feed in customers sites extents (MapInfo/DXF/SHP) & source data (ASCII and/or JPG) Remove unnecessary attributes and mosaic source ASCII files into a single input Create bounding box Create surface using SurfaceModeller Clip extents Apply text labels to contour outputs Write output formats Next Slide: Resolving the problems when creating a clipped surface modelFME Transformer in detail Main transformer used to clip the source ASCII file and produce the clipped TIN and Contours 2D and 3D points created from the clipped ASCII using a separate FME workspace Feed in customers sites extents (MapInfo/DXF/SHP) & source data (ASCII and/or JPG) Remove unnecessary attributes and mosaic source ASCII files into a single input Create bounding box Create surface using SurfaceModeller Clip extents Apply text labels to contour outputs Write output formats Next Slide: Resolving the problems when creating a clipped surface model

    12. Case Study - 3D topography solutions for CAD and GIS users Creating a clipped 3D Surface Flexibility of FME enables us to build a process in stages, replicating the processes that would be undertaken in CAD/GIS to achieve the same result Use the SurfaceDraper in conjunction with the SurfaceModeller Perform multiple iterations Read in the source site extents as a 2D vector The full rectangular TIN model is generated from the source ASCII grids The source digitised area used for the clipping extents is draped over the model in order to derive a 3D vector model of the clipping boundary This 3D clipping extent is then fed into a second SurfaceModeller as a Breakline, along with the source ASCII grid in order to recreate the TIN based on these new extents. This Breakline introduces a hard boundary in the TIN model and ensures that all triangles neatly butt up to these extents The resulting TIN model is then clipped using this 3D clipping boundary in order to output the final irregular TIN Next Slide: Transformers used, and key features Creating a clipped 3D Surface Flexibility of FME enables us to build a process in stages, replicating the processes that would be undertaken in CAD/GIS to achieve the same result Use the SurfaceDraper in conjunction with the SurfaceModeller Perform multiple iterations Read in the source site extents as a 2D vector The full rectangular TIN model is generated from the source ASCII grids The source digitised area used for the clipping extents is draped over the model in order to derive a 3D vector model of the clipping boundary This 3D clipping extent is then fed into a second SurfaceModeller as a Breakline, along with the source ASCII grid in order to recreate the TIN based on these new extents. This Breakline introduces a hard boundary in the TIN model and ensures that all triangles neatly butt up to these extents The resulting TIN model is then clipped using this 3D clipping boundary in order to output the final irregular TIN Next Slide: Transformers used, and key features

    13. Case Study - 3D topography solutions for CAD and GIS users Transformers Used and Key Features Simple transformers, used in a particular order Raster Mosaicker Surface Modeller (x2) Surface Draper Clipper Key Features: Clip to site Multiple formats Key benefits to customer: Ready to use data Clipped to site Optimised files size Different options depending on application Saves customer time and money Next Slide: Key benefits of using FME Transformers Used and Key Features Simple transformers, used in a particular order Raster Mosaicker Surface Modeller (x2) Surface Draper Clipper Key Features: Clip to site Multiple formats Key benefits to customer: Ready to use data Clipped to site Optimised files size Different options depending on application Saves customer time and money Next Slide: Key benefits of using FME

    14. Case Study - 3D topography solutions for CAD and GIS users Key Benefits (to Landmark) Confidence we know there will be a solution Flexible we can develop the solution iteratively as the situation/resources allow Accuracy as data resellers we need to ensure we are not removing information Scalable using FME Server we can incorporate solutions into repeatable packages Key Point - Similar benefits apply to other areas where FME is used Next Slide: End Key Benefits (to Landmark) Confidence we know there will be a solution Flexible we can develop the solution iteratively as the situation/resources allow Accuracy as data resellers we need to ensure we are not removing information Scalable using FME Server we can incorporate solutions into repeatable packages Key Point - Similar benefits apply to other areas where FME is used Next Slide: End

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