GIS Editor

Map Mode

In Map mode the editor connects via Internet to the SNSB Google Maps service or alternatively to the Open Street Maps service, regarding on the GIS-Editor Settings, and displays an online map which can be moved, zoomed and switched as usual. The status area shows the or respectively the symbol. The size of the map area adapts to the size of the working area, even when resizing the window.

In case of Google the controls for moving, zooming and map type are displayed by default. The overview window in the bottom right corner can be switched manually. The map can be adjusted to the user’s needs as follows:

• Select map area: Press and hold left mouse button and move the mouse
• Zoom map: Turn the mouse wheel (if any), double click (left or right mouse button) on a location
• Switch map type: Use Google map type control
• Hide Google controls: Click right mouse button to hide, left mouse button to show them again

In case of Open Street Maps the pan and zoom control is displayed by default. It can be switched off or on by clicking the left mouse button anywhere within the map area. The layer switch control is hidden and can be opened by pressing the or closed again by pressing the button on the right side. The map can be adjusted to the user’s needs as follows:

• Select map area: Press and hold left mouse button and move the mouse, or use the OSM pan control
• Zoom map: Turn the mouse wheel (if any), double click (left mouse button) on a location or use the OSM zoom control
• Switch map type: Open the layer switch and select a layer
• Hide or show pan and zoom control: Click left mouse button to toggle the control

If an appropriate area has been selected, just press the Add button , then the area will be scanned and added to the Sample List as a reference map. A little image of the map will appear on the toggle button in the Sample List. The controls should be switched off before adding to get a neat map image.

Then the mode will be switched to Shift mode automatically and the status symbol will change to indicating that world coordinates are present. The screen and world coordinates will be shown in the status lines if the mouse is moved over the map surface.

The maps are subject to the Mercator projection, which is the GIS Editor’s precondition for every bitmap used as a reference map. While the screen coordinates are linear in horizontal and vertical direction, the world coordinates are non linear in vertical direction.

GIS Editor

Shift Mode

This is the quasi default mode of the GIS Editor. The cursor changes to a move shape when touching the background map. The map is “frozen” and exists as an image sample on the sample list. Changing the map region or resolution is no longer possible. But the Shift Mode provides 2 features:

• Move the working area
• Zoom the working area

Moving the working area

Press and hold the left mouse button and move the mouse to shift the working area within the display window. This is useful when having loaded a map from a storage unit which is larger than the GIS Editor’s window, or in combination with zooming the working area.

Zooming the working area

Place the mouse cursor at the slider control, press and hold the left mouse button and move the control left to zoom out or right to zoom in the working area. The range of the zoom is from factor 0.6 to 3.0. The current value is displayed beneath the zoom control. Double click the slider control to reset the zoom to default value 1.0.

Enlarging the working area makes it more easy to place objects precisely. The relevant area then could be selected by moving the zoomed working area. Downsizing the working area gives an overview of large map regions.

Note that the resolution of the map itself does not change any more when zooming in. But objects on the map are created in vector graphics, so the markers, lines or areas will remain sharp and clear while zooming. And they will adapt there thickness smoothly to the size.

GIS Editor

Area Mode

This mode is used to create areas (polygons) on the background map. The cursor changes to a cross line when touching the background map. Each click on the left mouse button sets a new point of the polygon. Every click on the right mouse button clears the last point set. The closed polygon defined by the points is displayed completely at any time. When holding the left mouse button the point can be placed while the lines of the polygon are shown as a “rubber band” display.

To create more than one area for a sample, just click the button. This will finish the current polygon and start another one. It could be repeated without limitation of the number of polygons.

Setting the color

The areas are created as filled polygons, this means they have a border line (stroke) and a filling. The color of stroke and filling can be set independently or simultaneously by clicking the appropriate check boxes beneath the Color list box. Clicking on the list box will open a drop down menu with the complete set of 141 predefined brushes. Use the scroll bar to navigate to the preferred color and select it with the left mouse button.

Setting the transparency

Besides the color the transparency of the area could also be set for stroke and filling. In each edit mode the slider control is used for that. The area stroke or filling changes smoothly from invisible at the left till completely opaque on the right slider position. The value beneath the slider control indicates the opaqueness in a range from 0% to 100%. The default settings are 100% for stroke and 25% for filling.

Before adding the polygon to the Sample List an Identifier (ID) and a Description (Text) should be written to the text boxes in the control panel.

Clicking the Add button will put the current area(s) as one sample into the Sample List. The toggle button will show a small picture of the first area of the sample. The ID will be displayed above the button. Furthermore a tool tip will be created for the sample holding the ID and Description, which will pop up when moving the mouse over the toggle button or over the polygon in the working area.

GIS Editor

Line Mode

This mode is used to create line strings on the background map. The usage is adequate to the Area Mode. The cursor changes to a cross line when touching the background map. The points of the line strings can be set or cleared by clicking the mouse buttons. Clicking the button will switch to the next line string for the sample. The distance of the last drawn line string section is displayed beneath the status area.

Color and transparency can be set for the line strings using the appropriate controls, but only for stroke, because the line strings do not have a filling. Thus checking the Fill box will have no effect. After adding the lines to the sample list a small picture of the first line string will appear on the toggle button.

GIS Editor

Point Mode

This mode is used to create Points (object markers) on the background map. The usage is similar to the Area Mode. The cursor changes to a cross line when touching the background map. The object markers can be set by clicking the left mouse button, clicking the right mouse button will clear the last markers one by one again. The button has no impact, because each Point represents a complete object and needs not to be finished before creating the next one.

The shape of the object markers can be selected from a number of predefined Point symbols and icons within the Settingswindow, e.g.:

Pin:
Diamond:
Needle:
Cross:
Pyramid:
X:
Cone:
Square:
Questionmark:
Circle:
Minus:
Myxomycete:
Fungus:
Lichen:
Bryophyt:
Plant:
Evertebrate:
Mollusc:
Assel:
Insect:
Echinoderm:
Vertebrate:
Fish:
Reptile:
Bird:
Mammal:

Color can be set for the symbol markers using the appropriate controls. It depends on the selected point symbol, whether it just has a stroke (e.g. “Cross”) or also a filling (e.g. “Pin”). Transparency can be set for both, the symbol and icon markers. The stroke thickness and the size of the markers can be set in the Settings menu. After adding the object markers to the sample list a small picture of the collection will appear on the toggle button.

GIS Editor

Edit Mode

This mode is used to modify all samples (objects and images) which are currently visible on the working area. It applies to the elements of the Sample List as well as to the current sample.

Changing the position or shape of objects (points, line strings, areas)

To change an object one has to move the vertices (“corner points”) which are defining it. To do so just move the mouse close to a vertex to localize it. As soon as the corner has been grabbed the cursor changes its shape to a hand symbol .

Now press the left mouse button and hold it, then move the mouse to change the position of the vertex accordingly. The shape of the object or the marker will change in the same manner. Release the mouse button when the preferred position has been set.

Note that areas and line strings cannot be moved in total while keeping their shapes!

Changing the position or shape of images (maps)

Images (e.g. maps) can be moved completely (keeping their aspect ratio), scaled in horizontal and vertical direction and skewed within an affine transformation. Editing an image can be divided into 4 stages by grabbing and moving the following corners:

1. Top-left: Moving the total image by keeping its aspect ratio
2. Bottom-right: Squeezing or stretching the image horizontally and vertically
3. Bottom-left, top-right: Skewing the image in an affine way by keeping the corner points top-left and bottom-right at its positions
4. Bottom-right again: Skewing the image in an affine way by keeping the corner points top-left and bottom-left at its positions

Stages 1 to 4:

Changing color and transparency

Color and transparency can be set independently (or simultaneously) for the objects using the appropriate controls and check boxes for Stroke or Fill. The setting will affect all visible objects, so objects which should not be changed have to be switched off before with their toggle buttons. The color of images could not be changed, of course, but the transparency can be set if the Fill box is checked. The transparency of the background map cannot be changed.

GIS Editor

Adapt Mode

Essential for visualizing Geographical Objects is a background map with world coordinates. The GIS Editor’s Map mode offers a convenient way to create such a map, but it is restricted for the use of Google or OSM maps which are present in the web and are providing world coordinates. It would be nice to load scans of e.g. topographical or even historical maps into the working area and use them as background maps, but the problem is how to assign world coordinates to them.

The Adapt mode solves this in an easy way by executing the following steps. As a precondition a background map having world coordinates (e.g. a Google map) must be present which covers the area of interest of the new map to be referenced.

1. Load the new map image using the Load button . The image will be placed top left inside the working area.

2. Select Adapt mode by checking the Adapt radio button. The cursor changes to a pointer symbol having a green border when touching the new image and having a red one when touching the background map.

3. Now 3 reference points must be set alternately on background and new map to assign the appropriate locations (e.g. distinctive landmarks like road crossings). The last point can be modified as long as the map is not changed. The cursor always tells you what reference point will be set, according to its color and the number of dots in the middle:
   Note: It is reasonable to select distant points close to the edges of the new map, because this will give more accurate results.

   

4. When all reference points have been set and the cursor touches the alternate map, it changes to the finished shape . The next click will place the new map into the appropriate background map area.

   

The adapted image has been transformed to fit into the current world coordinates of the background map. Now the new map can be added to the sample list by pressing the Add button . When it is finally saved to disk by pressing the Save button , the new assigned world coordinates will be saved, too, in an XML file with the same name (see SaveSamples).

Sometimes it is difficult to place the new map and the reference map side by side, because the window is too small, and zooming out would blur the details needed for setting the reference points. If the new map covers the background map, the reference points can be set anyway

• for the new map by making it opaque with the transparency slider

• for the background map by making the new map transparent (less than 10% opacity) with the slider

  

Note: The Fill box must be checked to change the transparency of the new map. The background map’s transparency cannot be changed.