Visualisation of ENVI-met results using LEONARDOcopyright 1998,2006 by Michael BruseBack to start page

Introduction This document describes how to visualise ENVI-met binary result files (.EDI/.EDT) using the WINDOWS software LEONARDO 3.0. This is a Step-by-Step guide showing how to display the ENVI-met files. Only a very few features of LEONARDO are presented here. You should also refer to the full LEONARDO manual included in your LEONARDO distribution.Unfortunately, this is available only in German at the moment..... This document refers to the combination of LEONARDO 3.75+ and ENVI-met 3.1 data files. Due to memory restrictions, at least LEONARDO Version 3.75 is required to display ENVI-met 3.1 files. Contents Step 1: Getting startedStep 2: Using the DataNavigatorStep 3: Fine-tuning the map Data layer Special layer Vector layer Isoline layer

Start LEONARDO or create a new empty map by using the "New Map" button or the menu entry "File | New Map"

Each map consists of different layers of information which can be switched on and of by clicking on the green or red dot beside the name of the map layer (see Step 7). The following layers are available: Data: Displays continuous data (e.g. temperatures)Special: Displays singular data (e.g. buildings)Vector: Displays vectors (composed out of 2 data fields, one for the x- the other for the y-component) Metafile: Displays a WINDOWS- Metafile on the mapIsoline: Displays data as isolines (contour lines)Symbol: Displays data refering to 1 (or 100%) as an empty (0) to full (1 or 100%) circle (there are no real applications in ENVI-met for this layer type) Next Step: Using the DataNavigator

Step 2: Using the DataNavigatorNext step: Fine tuning the mapBack to visualisation start page

LEONARDO includes a special interface to ENVI-met data files which allows a simple navigation through the data. This interface is called DataNavigator. Start the DataNavigator by selecting menu entry "Tools | DataNavigator". Your screen should contain the following:

Select ENVI-met file Click on the folder symbol and select an ENVI-met data file. LEONARDO will read the information file (.EDI) and creates a list of all variables stored in the file. Also the title and the dimension of the simulation data are displayed at the bottom of the list. Up to this point, no data have been read into the map.

Select variables to display LEONARDO uses 5 internal layers for displaying data and each ENVI-met file contains a collection of several data. In order to bring those two ends together, you must assign the variables in the list to the corresponding map layer. To assign a variable to a map layer, select first the variable in the list

and then click on the assign button of the layer

This will tell LEONARDO to extract the selected variable out of the data file and put it on the selected layer (Pot. Temperature on Data Layer in this case) Hint 1: Using ENVI-met defaults in LEONARDOHint 2: Selecting the correct vector component Select type of section To create a two-dimensional map out of a three-dimensional data set you must specify the type and the position of a cross section. If your selected data is only two-dimensional, no cross sections can be selected. Select the type of section you need: „X-Y" for a horizontal view, „X-Z" for a vertical view from the front and „Y-Z" for a vertical view from the left side.

Depending on the type of section, one coordinate remains constant, for example the height z in an horizontal X-Y cut.

Define the cut position by setting the "Cut at..." edit field. The actual cut position is given in grids and in absolute meter.

Extracting data and build map After you have selected all variables to be imported into the map, you can extract the data from the ENVI-met file. To extract a 2D cut, press the "Extract 2D cut" button

Next step: Fine tuning the map

Step 3: Fine-Tuning the mapBack to visualisation start page

In this section you will see, how you can adjust the map to your personal needs.To have access to the different properties of the map layer, open the "Settings 2D" dialog in LEONARDO

This dialog is composed of several pages, each dealing with a certain aspect of the map or defining the settings of a specific map layer:

Select the map layer for more information:Data layerSpecial layerVector layer

Isoline layer

Data layer setupsee also: Special layer, Vector layer, Isoline layer Back to visualisation start page

LEONARDO works with an internal color palette of 30 colors, organised in 3 groups of 10 colors each. Colors 0..9 are set#1, colors 10..19 are set#2. The colors 20..29 are reserved for a grey scale. Thing to do to adjust the Data layer: Adjusting the start color (First Index Color). By default, color #0 is for a topography scale from green to brown, Color #10 starts a scale for data from blue to cyan. The default color palette is designed to be used with 10 colors (Number Colours). If you want to use more (up to 20) colors, you'll need to create a different palette (see next step). Change color paletteTo change the color palette, press "Edit Color sets…" In the upcoming dialog, you can change colors, load new palette files or save your palette here. Use drag&drop to re-arrange colors or mix new colors in the mixer and drop them into the color set. Adjust color scale rangeIf you don't like the color scale range calculated by LEONARDO, you can define your own. Deselect the option "Optimise key to existing data range" and set the first value to start the range and the step size for the scale classes. Use more than 10 colors

In case you need more than 10 colors, you can change the number of colors in the scale by editing "Number colors". Please note: Your palette should be created for more than 10 colors then. Otherwise there will be ugly changes between the two 10-color-scale palette areas. Use a floating color scale Select the option "Use floating color scale" if you prefer a smooth color scale instead of 10 single colors. (Looks nicer, but makes it harder to identify the value by its color) Ignoring hidden data pointsSelect the option "Ignore grid points with "Special" data". This will exclude any data value hidden by a special information from being included in the color scale range. If you don't use this option and there are undefined values below special information (for example a „0" inside a building whereas the rest of the data is around 290 to 300) the color scale range will include this value.

Special layer setupsee also: Data layer, Vector layer, Isoline layer Back to visualisation start page

The special layer is designed to display singular information in the map like buildings or plants. Different to the data layer, the value of any information stored on the special layer is a link to a special information. For example, the value „1" can identify a building on this grid. In order to display this information, you must link this value to a data set which defines the display color and the meaning to the information.To edit the Special layer settings, open the Settings 2D dialog and press the Special Layer tab.

In the screen shot above you see the default settings when visualising ENVI-met data files. The special information stored in ENVI-met data files contains information about the buildings and the leaf area density in divided into 6 classes. You can load the pre-defined dataset for ENVI-met by pressing the "ENVI-met defaults" button.To show a special in your map, select the "Show Special Layer" option.LEONARDO provides a special key (legend) for the special layer. To include the key in the map, select the "Show key" option.

Vector Layer setupsee also: Data layer, Special layer, Isoline layer Back to visualisation start page

The vector layer in LEONARDO supports a huge number of options to generate a nice-looking representation of the wind flow in the model domain. Adjust vector scale In order to draw the vector arrows in the right size, they must be scaled to the grid point size. Open the vector settings page by clicking on the Vector Layer tab

Use filled vector arrowsSelecting the "Filled vector arrows" option will create solid tops of the arrow. The direction of the vector is more readable compared to the non-filled vectors, but small vectors will all look the same. Select between ordered and random vector displayLEONARDO supports two ways of drawing vectors: the ordered display and the random display. Using the "Draw random vectors" option will produce a more chaotic vector display because the vectors are placed randomly on the map (right image below) rather than in the centre of the grid (left image below).To adjust the map to your data set, define the number of vectors to be drawn in the box below the option box.

Ordered vector display (left) and random-style vector display Selecting the vector color

LEONARDO offers a wide range of possibilities to select the color of the vectors

To draw all vectors with the same color, select a color and de-select the "Use Data layer color" option. If you wish to draw vectors using the data layer colors, select the option "Use Data-Layer color". The vectors will be displayed according to the color of the data layer. To adjust the colors, you must fist adjust the data layer key settings so that the colors of the data layer are as you like them to bet (top figure in the example below). Then, switch off the data layer, and select the "Use data layer color" option. Now the vectors are drawn with the color of the data layer (bottom figure in the example below). Important: The data layer must be switched off, otherwise you won't see anything ! Example: To draw the color of the vector according to their value, the absolute wind speed is stored as variable on the Data layer. After adjusting the color scale, the data distribution might look as follows:

Now, turn off the Data layer and select "Use Data-Layer color" and you will get this result:

Isoline layer setupsee also: Data layer, Special layer, Vector layer Back to visualisation start page

The Isoline layer provides a basic functionality for drawing isolines (contour lines) into the map. The isolines are drawn grid-by-grid, not as continuous lines. Therefore the isoline output cannot compete with other professional contouring software such as SURFER from Golden Software, for example. If you need high quality isolines, we suggest to export the data, produce an isoline image in the external software package and save it as a WINDOWS Metafile. You can load this file onto the metafile layer then. This section shows you how to use the LEONARDO isoline functionality. Before you can create isolines, the data to be displayed must be loaded onto the Isoline layer using the DataNavigator. To adjust the settings for the Isoline layer, click on the Isoline Layer tab.

Find the Isolayer minimum and maximumPress "Find Min/Max…" to search for the minimum and maximum values on the isoline layer. When working with ENVI-met files, data inside of buildings (Special ID=1) are often on their initial value or not defined. You can tell LEONARDO to ignore those grids points when constructing isolines and search for the minimum and maximum value on the isoline layer. Select a reasonable interval for drawing the isolinesFor example, if the first line (minimum line) is at 0.00, the next isolines will be 10.00, 20.00, 30.00 and so on until the maximum isoline is plotted.

Adjust isolines close to buildings If the option "ignore grids with special=" is selected, no isolines will be constructed towards grids with the selected ID (select "1" here for buildings in ENVI-met). The following two pictures illustrate this concept: In the upper figure, the "ignore grids" option is not used. LEONARDO tries to build isolines including the undefined (random or initial) values below the buildings. This looks messy, because a lot of isolines are constructed around the undefined data. The figure below shows the same data set but with the "ignore grids" function enabled and ignoring data below specials=1. This looks much better.

Isolines drawn without ignoring grids with special data

Isolines with ignoring grids with special data = 1 (buildings)Select style and color of isolinesThe style and the color of the isolines can be selected in various ways

Isolines are organized in 3 classes: positive, negative and zero isolines.

For each of the 3 types, you can select the line width, the line color and the line style. (Different line styles only work with 1 pt width at the moment).The last line style is "empty" which means that the lines are not drawn. You can also color the isolines depending on their value. Check the option "Use color settings from Data-Layer key" to enable this function. In this case, the settings from the data key (number of classes, number of colors, class values) are used to determinate, in which color the isoline is drawn. Note: Different to the vector layer, where the values on the data layer are used to identify the color of the vector, the isoline layer values will be used here to select the color.

Control the isoline text labels

LEONARDO provides a very simple mechanism for labeling the isolines. Use the "Show labels at isolines" option to show or hide the labels.The associated "Label Distance in grids" is an indicative value how many labels are placed along the isolines. However, as mentioned before, the isolines are drawn grid-by-grid, not as a line object. Therefore LEONARDO cannot exactly determinate when the last label on an isoline was drawn. Low values for label distance will produce many labels, high values will produce few labels. You should test, which value fits your needs and data best. "Unit name" is the data unit name written behind the label value, "Nr of digits" tells LEONARDO how many decimal digits should be generated.

"Draw negative labels italic" and "Use same color as isoline" controls the font appearance of the labels. The "restrict labels" option is another way to control the design of the map. Selecting "medium smooth segments" will prevent very curvy isolines of being labelled, "smooth segments" will restrict labels to very smooth isoline sections. Finally "no restriction" will put labels everywhere where they should appear following the label distance value.