> The basic idea is to densify the vertices in areas with high distortion and > possibly removing ones in areas with low distortion. For visualisation > purposes I think this is neat solution but it may not be desirable in a GIS > where you want the user to have full control over the vertices in a geometry.
Indeed. There is difference between the data vertices and how the data should be visualised. I think edges shouldn't be visualised with straight edges between vertices, but with geodesics. This means intermediate points (for visualisation only) are needed. As long as not all GIS software is visualising edges as geodesics, I recommend Dutch data creators to add intermediate points themselves. For common projections like ETRS89-LCC, LAEA, UTM etc., I analysed the required line segment length between intermediate points. For Europe the worst cases for common projections are World Mercator and Web Mercator. I made a graph for the relation between line segment length and deviation between a straight line and the geodesic for these projections: https://www.euref.eu/sites/default/files/symposia/2024Barcelona/15-01-Lesparre.pdf (slide 12) which shows for example: for 1 cm accuracy, the vertices should not more than 400 m apart in North Scandinavia and not more than 1000 m apart in the South Mediterranean. Jochem Disclaimer: De inhoud van deze e-mail is vertrouwelijk en uitsluitend bestemd voor de geadresseerde(n). Gebruik, openbaarmaking, vermenigvuldiging, verspreiding en/of verstrekking van deze informatie aan derden is niet toegestaan. Op al onze producten en diensten zijn onze algemene leveringsvoorwaarden van toepassing [https://www.kadaster.nl/algemene-leveringsvoorwaarden]. Disclaimer: This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you are not the intended recipient, you are notified that disclosing, copying, distributing or taking any action in reliance on the contents of this information is strictly prohibited. Our general terms and conditions of delivery apply to all our products and services [https://www.kadaster.com/general-terms-and-conditions].
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