## 7. Indicators of points

> 7.1 Architecture of indication

> 7.2 Indication of plane points

> 7.3 Indication of spatial points

> 6.4 Filtration

## 7.1 Architecture of indication

> This softwate enables us to indicate sets of points. The architecure of the indication is presented on the following picture:

> An iterator provides necessary data. A transformer transforms data to coordinates of points and visual parameters. Indicator also indicates points.

## 7.2 Indication of plane points

> Indication of plane points one to one corresopnds to main architecture of indication. Indicator corresponds to the . A typical example of indication of plane points is presinted on the following picture::

> In this picture we have an Iterator linked to database Query. Also we have such necessary ingredients as a Transformation and an Indicator. A Filter is used for filtration of information. The editor of properties of indicator looks like:

> This property editor on the picture associates Formula_2 and Formula_1 of Transformation to X and Y coordinates of a point respectivelily. The Formula_3, Formula_4 and Formula_5 of Transformation are associated to Red, Green an Blue color of a point respectively. The Formula_6 is associated with the size of the point. Indication of points is situated in the right part of editor of properties. If TYCHO and HIPPARCOS DATABASE is installed then user can try this example. Click here to download it.

## 7.3 Indication of spatial points

> Every indication of a set of spatial points needs the array of poins and virtual video camera. It is presented on the following picture:

> We have a set of rigid connected to Frame of points. Also we have a video camera that is rigid connecteted to Frame of camera. You can observe a set of points throught a window that corresponds to the camera. It is possible to use more than one cameras and observe a set of points throught a set of windows. Both Frame of camera and Frame of points may be mobile. Then user can observe animated picture.

> Let us show indication of spatial points step by step.

> ### a) Step 1. Generation of a set of points.

> Genreation of a set of points corresponds to common arcitecture of indication and its example is presented on the following picture:

> In this picture component Database and Data represents iterarator layer of arcitecture of indication. Compoonents belong to transformation level. Component Stats is an indicator. Transfomation performs calculatioin of positions, sizes and colors of points. The button corresponds to an indicator. Its editror is presented on the following picture:

> In this picture cooordinates of points correspond to Formula_1, Formula_2, Formula_3 of "X Y Z" component. Similarly formulas of "Color Size" component correspond to sizes and colors of points.

> b) Step 2. Setting mobile camera.

> During this step a user should set a camera and link it to reference frame. It is presented on the following picture

> In this picture the Rotation component contains motion equaitions an Frame2 is linked to these equatios mobile reference frame. The Indicator is rigidly linked to this frame.

> b) Step 3. Linking camera and set of points.

> During this step you should link a camera to the set of points by a link. If TYCHO and HIPPARCOS DATABASE is installed then user can try an example of indication of spatial points. Click here to download it.

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