Modelling Shadow Using 3D Tree Models in High Spatial and Temporal Resolution
2. Materials and Methods
2.1. The Scanned Tree and Its Location
2.2. Input Data
2.4. Computing Vertices of Cylinders as a Base for Tree Shadow Projections
2.5. Projecting the Cylinder Shadow onto the Ground and Calculating Energy Loss Due to Shading
2.6. Computing Ellipsoids to Simulate Leaves
- Improvement of the leaf simulations. Leaf parameters vary between tree species, within the tree crown and throughout the growing season [15,16,17]. Thus, to generate realistic shadow projections of tree crowns, it is crucial to simulate leaves as realistically as possible. At present, our model simulates leaves by adding a single ellipsoid to the end of branches of a radius of less than 0.5 cm, and the ellipsoids increase in their radius each month to simulate leaf growth. We will replace these ellipsoids with more realistic leaf-like polygons, taking also their spatial distribution within tree crowns into account.
- Validation of the results generated by the model by comparing them with on-site light measurements. In case of discrepancies, the model needs to be adapted accordingly.
Conflicts of Interest
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Rosskopf, E.; Morhart, C.; Nahm, M. Modelling Shadow Using 3D Tree Models in High Spatial and Temporal Resolution. Remote Sens. 2017, 9, 719. https://doi.org/10.3390/rs9070719
Rosskopf E, Morhart C, Nahm M. Modelling Shadow Using 3D Tree Models in High Spatial and Temporal Resolution. Remote Sensing. 2017; 9(7):719. https://doi.org/10.3390/rs9070719Chicago/Turabian Style
Rosskopf, Elena, Christopher Morhart, and Michael Nahm. 2017. "Modelling Shadow Using 3D Tree Models in High Spatial and Temporal Resolution" Remote Sensing 9, no. 7: 719. https://doi.org/10.3390/rs9070719