CashFlow, A Visualization Framework for 3D Flow - Studierstube ...

Software Design3.10. Render Nodes– Parameterization MapperData is reparameterized with a set of constant, linear and cubic intervals.• Geometry MapperThis large group of mappers include algorithms operating on grids.– Iso–value MapperCreation of polygonal surfaces using 2D & 3D cells. A scalar value callediso–value is defined as a parameter. At each vertex in each cell a scalarvalue has to be defined, which is used to create the polygonal surface or theiso–line in 2D.– Carpet Plot MapperA field of scalar values or a vector field is used to distort a surface.– Streamline MapperThis mapper is responsible for all kinds of particle tracers and streamlinesintegration using seed points.– Cutting MapperCutting planes and surfaces are used to segment data.Only one group of algorithms are not implemented as mappers namely the renderingalgorithms.3.10 Render NodesThis group of nodes implement rendering algorithms. The render nodes request datafrom the DataAccess nodes and from a Grid node. Per definition Render nodes createimages only and do not create new data, that is stored in a MultiData node. If a Rendernode also creates data, that is stored in a MultiData node it has to be derived fromMapper node.The Render algorithms can be subdivided as follows:• Point Cloud RendererThe most basic Render node draws a point where a vertex is. The point can alsobe color coded. This visualization can be useful for example to investigate thedensity of a grid.• Glyph RendererThis is the complement of the point renderer in vector fields. At each selectedpoint a glyph shows the direction of the flow. Glyphs can be also used to visualizemultidimensional data.• Cell RendererThe grid is divided into cells and each cell is rendered. One traditional cellrenderer is the cuberille renderer [LC85].• Wireframe RendererThe grid or parts of the grid are visualized using a wire–frame.62