Dynamic Mapping of Raster-Data For 3D Geovirtual Environments: Dynamic Mapping of Raster-Data For 3D Geovirtual Environments Matthias Trapp , Jürgen Döllner Hasso-Plattner-Institute, University of Potsdam, Germany 13 th International Conference on Information Visualisation 14-17 July
motivation: motivation Using 3D geovirtual environments as scenery for visualization of dynamic geo-referenced thematic data
motivation: motivation Using 3D geovirtual environments as scenery for visualization of dynamic geo-referenced thematic data Preprocessing Time: days-hours Preprocessing Time: hours-minutes Preprocessing Time: minutes
wrap-up: challenges & goals: wrap-up: challenges & goals Strong coupling of geometry and appearance: Real-time rendering constraints Large-scale data sets require specific out-of-core renderer Results in (time-consuming) data pre-processing Cannot be used to visualize time-critical data Goals: partially decoupling geometry and appearance to… …enable dynamic multi-texture mapping …enable color transfer function …for a large number of mapping configurations …in real-time
overview: dynamic texture mapping: overview: dynamic texture mapping Given input data: 3D point (fragment) of original model Data & color layers Mapping parameterizations Requested: final color Data & color layers: 1D/2D/3D image/textures data values, masks color gradients
texture coordinate generation: texture coordinate generation Projective texture mapping [Everitt 2001] Orthogonal projection matrix: U V
color transfer functions: color transfer functions Describes color mapping of data values Define blending equations between mappings
rendering at a glance: rendering at a glance Extending OpenGL/DirectX multi-texturing pipeline Single-pass rendering: Per-fragment dynamic texturing using shader programs GPU Data representation: texture arrays Projective mappings encoded in texture-buffers Performance evaluation: # Vertex # Mappings FPS without FPS with FPS loss (%) 1,040,503 3 10.41 9.87 5.19 41,032 4 52.88 51.20 3.18 61,756 27 156.10 27.94 82.10 6 4 1063.83 236.97 77.72 37,404 16 206.21 45.70 77.84 6 6 1075.27 110.54 89.72
application examples: application examples Hierarchical combination of raster data layers Building category data Traffic frequency data Data Layer: Color Layer : Data Layer: Color Layer :
application examples: application examples Object or route highlighting Landmark objects Landmark objects Route
application examples: application examples Projective symbols to facilitate the design of interactive 3D digital maps
application examples: application examples Focus + context visualization: 2D magic lenses
conclusions: conclusions Summary: Extendable concept for dynamically mapping 2D raster-data Approach based on projective texture mapping Fully-hardware accelerated implementation Limitations: Works only for 3D GeoVE that can be approximated by a plane Limited texture resolution Future Work Extend color transfer to style transfer functions thank you...: thank you... Contact: Matthias Trapp
[email protected] Jürgen Döllner
[email protected] Computer Graphics System Group www.hpi.uni-potsdam.de/3d Researchgroup 3D-Geoinformation www.3dgi.de