207 |
<inlinemediaobject> |
<inlinemediaobject> |
208 |
<imageobject> |
<imageobject> |
209 |
<imagedata fileref="../images/3_2_zoomin.png" format="PNG"/> |
<imagedata fileref="../images/3_2_zoomin.png" format="PNG"/> |
210 |
|
</imageobject> |
211 |
|
<imageobject> |
212 |
|
<imagedata fileref="./images/3_2_zoomin.eps" format="EPS"/> |
213 |
</imageobject> |
</imageobject> |
214 |
<textobject> <phrase>ZoomIn Tool</phrase> </textobject> |
<textobject> <phrase>ZoomIn Tool</phrase> </textobject> |
215 |
</inlinemediaobject> |
</inlinemediaobject> |
223 |
<inlinemediaobject> |
<inlinemediaobject> |
224 |
<imageobject> |
<imageobject> |
225 |
<imagedata fileref="../images/3_2_zoomout.png" format="PNG"/> |
<imagedata fileref="../images/3_2_zoomout.png" format="PNG"/> |
226 |
|
</imageobject> |
227 |
|
<imageobject> |
228 |
|
<imagedata fileref="./images/3_2_zoomout.eps" format="EPS"/> |
229 |
</imageobject> |
</imageobject> |
230 |
<textobject> <phrase>ZoomOut Tool</phrase> </textobject> |
<textobject> <phrase>ZoomOut Tool</phrase> </textobject> |
231 |
</inlinemediaobject> |
</inlinemediaobject> |
239 |
<inlinemediaobject> |
<inlinemediaobject> |
240 |
<imageobject> |
<imageobject> |
241 |
<imagedata fileref="../images/3_2_pan.png" format="PNG"/> |
<imagedata fileref="../images/3_2_pan.png" format="PNG"/> |
242 |
|
</imageobject> |
243 |
|
<imageobject> |
244 |
|
<imagedata fileref="./images/3_2_pan.eps" format="EPS"/> |
245 |
</imageobject> |
</imageobject> |
246 |
<textobject> <phrase>Pan Tool</phrase> </textobject> |
<textobject> <phrase>Pan Tool</phrase> </textobject> |
247 |
</inlinemediaobject> |
</inlinemediaobject> |
252 |
<inlinemediaobject> |
<inlinemediaobject> |
253 |
<imageobject> |
<imageobject> |
254 |
<imagedata fileref="../images/3_2_fullextent.png" format="PNG"/> |
<imagedata fileref="../images/3_2_fullextent.png" format="PNG"/> |
255 |
|
</imageobject> |
256 |
|
<imageobject> |
257 |
|
<imagedata fileref="./images/3_2_fullextent.eps" format="EPS"/> |
258 |
</imageobject> |
</imageobject> |
259 |
<textobject> <phrase>Full Extent Tool</phrase> </textobject> |
<textobject> <phrase>Full Extent Tool</phrase> </textobject> |
260 |
</inlinemediaobject> |
</inlinemediaobject> |
265 |
<inlinemediaobject> |
<inlinemediaobject> |
266 |
<imageobject> |
<imageobject> |
267 |
<imagedata fileref="../images/3_2_fulllayerextent.png" format="PNG"/> |
<imagedata fileref="../images/3_2_fulllayerextent.png" format="PNG"/> |
268 |
|
</imageobject> |
269 |
|
<imageobject> |
270 |
|
<imagedata fileref="./images/3_2_fulllayerextent.eps" format="EPS"/> |
271 |
</imageobject> |
</imageobject> |
272 |
<textobject> <phrase>Full Layer Extent Tool</phrase> </textobject> |
<textobject> <phrase>Full Layer Extent Tool</phrase> </textobject> |
273 |
</inlinemediaobject> |
</inlinemediaobject> |
280 |
<inlinemediaobject> |
<inlinemediaobject> |
281 |
<imageobject> |
<imageobject> |
282 |
<imagedata fileref="../images/3_2_fullshapeextent.png" format="PNG"/> |
<imagedata fileref="../images/3_2_fullshapeextent.png" format="PNG"/> |
283 |
|
</imageobject> |
284 |
|
<imageobject> |
285 |
|
<imagedata fileref="./images/3_2_fullshapeextent.eps" format="EPS"/> |
286 |
</imageobject> |
</imageobject> |
287 |
<textobject> <phrase>Full Shape Extent Tool</phrase> </textobject> |
<textobject> <phrase>Full Shape Extent Tool</phrase> </textobject> |
288 |
</inlinemediaobject> |
</inlinemediaobject> |
299 |
<inlinemediaobject> |
<inlinemediaobject> |
300 |
<imageobject> |
<imageobject> |
301 |
<imagedata fileref="../images/3_3_identify.png" format="PNG"/> |
<imagedata fileref="../images/3_3_identify.png" format="PNG"/> |
302 |
|
</imageobject> |
303 |
|
<imageobject> |
304 |
|
<imagedata fileref="./images/3_3_identify.eps" format="EPS"/> |
305 |
</imageobject> |
</imageobject> |
306 |
<textobject> <phrase>Identify Tool</phrase> </textobject> |
<textobject> <phrase>Identify Tool</phrase> </textobject> |
307 |
</inlinemediaobject>. |
</inlinemediaobject>. |
317 |
<inlinemediaobject> |
<inlinemediaobject> |
318 |
<imageobject> |
<imageobject> |
319 |
<imagedata fileref="../images/3_3_label.png" format="PNG"/> |
<imagedata fileref="../images/3_3_label.png" format="PNG"/> |
320 |
|
</imageobject> |
321 |
|
<imageobject> |
322 |
|
<imagedata fileref="./images/3_3_label.eps" format="EPS"/> |
323 |
</imageobject> |
</imageobject> |
324 |
<textobject> <phrase>Label Tool</phrase> </textobject> |
<textobject> <phrase>Label Tool</phrase> </textobject> |
325 |
</inlinemediaobject>. |
</inlinemediaobject>. |
372 |
image layers. Shape layers consist of vector based shapes with |
image layers. Shape layers consist of vector based shapes with |
373 |
geo-referenced coordinates. There are three types of supported |
geo-referenced coordinates. There are three types of supported |
374 |
shapes: polygons, lines, and points. Image layers can be any image |
shapes: polygons, lines, and points. Image layers can be any image |
375 |
file format supported by GDAL. The images must have a geographic |
file format supported by GDAL. The images must have geographic |
376 |
coordinate data either embedded within the file, or in a seperate |
coordinate data either embedded within the file, or in a seperate |
377 |
file that is in the same directory as the image file used for the |
file that is in the same directory as the image file. GeoTIFF files |
378 |
layer. GeoTIFF files work very well with Thuban and were designed |
work very well with Thuban and were designed specifically to be image |
379 |
specifically to be image layers in GIS programs. |
layers in GIS programs. |
380 |
</para> |
</para> |
381 |
</section> |
</section> |
382 |
|
|
436 |
|
|
437 |
<chapter><title>Layer Classifications</title> |
<chapter><title>Layer Classifications</title> |
438 |
<para> |
<para> |
439 |
|
A layer classification is a way of assigning drawing properties to |
440 |
|
groups of shapes based on attributes stored in the layer's table. |
441 |
|
Only layer's with shapes can have a classification; image layers |
442 |
|
cannot be classified. |
443 |
|
</para> |
444 |
|
<para> |
445 |
|
A classification consists of a number of groups, with each group |
446 |
|
having a value or range of values to match against, and symbol |
447 |
|
properties which control how a shape is drawn on the map. The user |
448 |
|
selects which field in the table is used by the classification and |
449 |
|
when the map is drawn the value for that field for each shape is |
450 |
|
compared with each group's value. The properties of the first group |
451 |
|
to match are used to draw the shape. This allows the user to get a |
452 |
|
visual impression of not only how the data is laid out but also what |
453 |
|
kind of data lies where. |
454 |
|
</para> |
455 |
|
<para> |
456 |
|
A layer always has a classification. When a new layer is added to the |
457 |
|
map, a default classification is created with the DEFAULT group. This |
458 |
|
group cannot be removed. Every shape in the layer, regardless of its |
459 |
|
attributes, will match this group. |
460 |
</para> |
</para> |
461 |
|
|
462 |
<section><title>Adding and Removing Classes</title> |
<section><title>Editing Classifications</title> |
463 |
<para> |
<para> |
464 |
|
A layer's classification can be modified under the properties dialog |
465 |
|
(<menuchoice> |
466 |
|
<guimenu>Layer</guimenu> |
467 |
|
<guimenuitem>Properties</guimenuitem> |
468 |
|
</menuchoice>). The layer's classification field can be set to None, |
469 |
|
which simply assigns a DEFAULT group to the classification. No new |
470 |
|
groups can be added to the classification if the field is None. |
471 |
|
The user must first select a field to classify on. New groups can |
472 |
|
be added to the classification with the <guibutton>Add</guibutton> |
473 |
|
button. |
474 |
|
</para> |
475 |
|
<para> |
476 |
|
The order of the groups in the classification is significant |
477 |
|
except for the DEFAULT group, which remains at the top. When shapes |
478 |
|
are matched against groups the matching begins at the first group |
479 |
|
other than the DEFAULT group so that groups higher in the list will |
480 |
|
be checked first. Matching for a |
481 |
|
given shape will stop at the first group that matches. The user can |
482 |
|
use <guibutton>Move Up</guibutton> and <guibutton>Move Down</guibutton> |
483 |
|
to change the order of the groups. The DEFAULT group will always |
484 |
|
match a shape that hasn't matched another group. |
485 |
</para> |
</para> |
486 |
|
<para> |
487 |
|
The Value column of the classification table is the value that will |
488 |
|
be matched when the map is being drawn. The type of data that can |
489 |
|
entered into this field depends on the type of data of the |
490 |
|
classification field. |
491 |
|
</para> |
492 |
|
<para> |
493 |
|
If the field is of type Text, anything entered |
494 |
|
into the field is valid. The text will be compared literally to the |
495 |
|
value of the shape attribute, including case sensitivity. |
496 |
|
If the type is Integer, then any valid integer may be entered. In |
497 |
|
addition, with special syntax, a range of values can be entered. |
498 |
|
A range from <varname>start</varname> to <varname>end</varname> |
499 |
|
inclusive is specifed like this: <literal>[start;end]</literal>. |
500 |
|
The exclusive range is specified like this: |
501 |
|
<literal>]start;end[</literal>. Ranges can include infinity like |
502 |
|
this: <literal>[-oo;oo]</literal>. Field types can also be of type |
503 |
|
Decimal. They represent any rational number and can be used in ranges |
504 |
|
as well. |
505 |
|
</para> |
506 |
</section> |
</section> |
507 |
|
|
508 |
<section><title>Symbols</title> |
<section><title>Symbols</title> |
509 |
<para> |
<para> |
510 |
|
Each type of shape has its own type of symbol. Thuban supports three |
511 |
|
types of shapes: polygons, lines, and points. Polygons and points have |
512 |
|
outline and fill color, while lines have only line color. Each group |
513 |
|
has associated symbol properties. To edit the symbol properties for a |
514 |
|
group the user can double click on the Symbol column or select a |
515 |
|
group and click the <guibutton>Edit Symbol</guibutton> button. |
516 |
</para> |
</para> |
517 |
</section> |
</section> |
518 |
|
|
519 |
<section><title>Generating Classes</title> |
<section><title>Generating Classes</title> |
520 |
<para> |
<para> |
521 |
|
Creating a classification by hand can be tedious. |
522 |
|
Thuban, therefore, provides a means of generating an entire |
523 |
|
classification at once while still giving the user control over |
524 |
|
how it appears. Clicking <guibutton>Generate Class</guibutton> |
525 |
|
opens the <varname>Generate Classification</varname> dialog. |
526 |
|
Under the <varname>Generate</varname> pulldown there are at most |
527 |
|
three different ways to generate classifications: |
528 |
|
Unique Values, Unique Distribution, and Quantiles. Some options |
529 |
|
may not be available if they data type for the field does not |
530 |
|
support them. For instance, <varname>Unique Distribution</varname> |
531 |
|
doesn't make sense for a Text field. |
532 |
</para> |
</para> |
533 |
|
<para> |
534 |
|
For every way of generating a classification, a color scheme must |
535 |
|
be selected. Thuban provides several different color schemes that |
536 |
|
affect how the group properties change over the classification. |
537 |
|
It is also possible to create a custom color scheme. Selecting |
538 |
|
this option will display two symbols: the one of the left has the |
539 |
|
properties of the first group and the one on the right has the |
540 |
|
properties of the last group. Thuban will interpolate between these |
541 |
|
two properties to generate the other groups. |
542 |
|
</para> |
543 |
|
<para> |
544 |
|
The Unique Values option lets the user select specific values that |
545 |
|
appear in the table. Clicking <guibutton>Retrieve From Table</guibutton> |
546 |
|
searches the table for all unique values and displays them in the |
547 |
|
list on the left. Items can be selected and moved to the list on the |
548 |
|
right. Each list can be sorted or reversed for easier searching. |
549 |
|
The classification that is generated will be in the same order as |
550 |
|
the list on the right. |
551 |
|
</para> |
552 |
|
<para> |
553 |
|
The Unique Distribution option creates a user specified number of |
554 |
|
groups of ranges such that each range covers equal intervals. The |
555 |
|
minimum and maximum values can automatically be retrieved from the |
556 |
|
table by clicking <guibutton>Retrieve From Table</guibutton>. The |
557 |
|
stepping is how large each interval is. Adjusting this value will |
558 |
|
automatically recalculate how many groups is appropriate. |
559 |
|
</para> |
560 |
|
<para> |
561 |
|
The Quantiles option generates ranges based on the number items |
562 |
|
in the input set. For example, by specifying 5 groups Thuban will |
563 |
|
generate groups with appropriate ranges such that 20% of the table |
564 |
|
data is in each group. If it is impossible to generate exact |
565 |
|
grouping, Thuban will issue a warning but allow the user to continue. |
566 |
|
</para> |
567 |
</section> |
</section> |
568 |
</chapter> |
</chapter> |
569 |
|
|
570 |
<chapter><title>Projection Management</title> |
<chapter><title>Projection Management</title> |
571 |
<para> |
<para> |
572 |
|
Projections control how the geographic data is displayed on the screen. |
573 |
|
If multiple layers are loaded into Thuban where the geographic data |
574 |
|
is in a different projection system, then the user must tell Thuban |
575 |
|
which projection each layer has. The user must also tell Thuban which |
576 |
|
projection the map is in. This can be the same as the layers or a different |
577 |
|
projection in which case the layers are reprojected into that space. |
578 |
|
The map projection can be set using |
579 |
|
<menuchoice> |
580 |
|
<guimenu>Map</guimenu> |
581 |
|
<guimenuitem>Projection</guimenuitem> |
582 |
|
</menuchoice> and the layer projection can be set using |
583 |
|
<menuchoice> |
584 |
|
<guimenu>Layer</guimenu> |
585 |
|
<guimenuitem>Projection</guimenuitem> |
586 |
|
</menuchoice>. |
587 |
</para> |
</para> |
588 |
|
<para> |
589 |
|
Thuban is distributed with a sample collection of projections. The |
590 |
|
user can create new projections and make them available to all |
591 |
|
future Thuban sessions. They may also be exported and imported so |
592 |
|
that custom projections can be distributed to others. |
593 |
|
</para> |
594 |
|
<section><title>Selecting a Projection</title> |
595 |
|
<para> |
596 |
|
The available projections are listed on the left. If the layer |
597 |
|
or map already has a projection it will be initially highlighted |
598 |
|
and will end with <varname>(current)</varname>. Selecting |
599 |
|
<varname>None</varname>will cause Thuban to use the data as |
600 |
|
it appears in the source file and will not use a projection. |
601 |
|
</para> |
602 |
|
</section> |
603 |
|
<section><title>Editing a Projection</title> |
604 |
|
<para> |
605 |
|
Whenever a projection is selected from the list its properties |
606 |
|
are displayed on the right. These properties can be changed |
607 |
|
and the changes saved to the selected projection using |
608 |
|
the <guibutton>Update</guibutton>. Only a projection that comes |
609 |
|
from a file can be updated, so if the current layer's projection |
610 |
|
is selectd, <guibutton>Update</guibutton> will be disabled. |
611 |
|
The <guibutton>Add to List</guibutton> adds the projection to the |
612 |
|
list of available projections as a new entry, and thus make it |
613 |
|
available to future Thuban sessions. Clicking <guibutton>New</guibutton> |
614 |
|
will create an entirely new, empty projection. The |
615 |
|
<guibutton>Remove</guibutton> button will permanantly remove a |
616 |
|
projection from the list of available projections. |
617 |
|
</para> |
618 |
|
</section> |
619 |
|
<section><title>Importing/Exporting Projections</title> |
620 |
|
<para> |
621 |
|
The projections that appear in the list of available projections |
622 |
|
can be exported to another file that the user chooses. By selecting |
623 |
|
one or more projections and clicking <guibutton>Export</guibutton> |
624 |
|
the user will be able to select a file to store those projections. |
625 |
|
The file can then be distributed to other Thuban users. To import |
626 |
|
a projection file the user can click <guibutton>Import</guibutton>. |
627 |
|
The imported projections are added to the list and are then available |
628 |
|
to the current session and any future Thuban session. |
629 |
|
</para> |
630 |
|
</section> |
631 |
</chapter> |
</chapter> |
632 |
|
|
633 |
<chapter><title>Table Management</title> |
<chapter><title>Table Management</title> |
643 |
<appendix><title>Supported Data Sources</title> |
<appendix><title>Supported Data Sources</title> |
644 |
<para> |
<para> |
645 |
</para> |
</para> |
646 |
|
<variablelist> |
647 |
|
<varlistentry> |
648 |
|
<term>Shapefile</term> |
649 |
|
<listitem><para></para></listitem> |
650 |
|
</varlistentry> |
651 |
|
|
652 |
|
<varlistentry> |
653 |
|
<term>DB2 file</term> |
654 |
|
<listitem><para></para></listitem> |
655 |
|
</varlistentry> |
656 |
|
|
657 |
|
</variablelist> |
658 |
</appendix> |
</appendix> |
659 |
|
|
660 |
<appendix><title>Supported Projections</title> |
<appendix><title>Supported Projections</title> |
661 |
<para> |
<para> |
662 |
</para> |
</para> |
663 |
|
<variablelist> |
664 |
|
<varlistentry> |
665 |
|
<term>Geographic</term> |
666 |
|
<listitem><para>Geographic</para></listitem> |
667 |
|
</varlistentry> |
668 |
|
<varlistentry> |
669 |
|
<term>Lambert Conic Conformal</term> |
670 |
|
<listitem><para>Lambert Conic Conformal</para></listitem> |
671 |
|
</varlistentry> |
672 |
|
<varlistentry> |
673 |
|
<term>Transverse Mercator</term> |
674 |
|
<listitem><para>Transverse Mercator</para></listitem> |
675 |
|
</varlistentry> |
676 |
|
<varlistentry> |
677 |
|
<term>Universal Transverse Mercator</term> |
678 |
|
<listitem><para>Universal Transverse Mercator</para></listitem> |
679 |
|
</varlistentry> |
680 |
|
</variablelist> |
681 |
</appendix> |
</appendix> |
682 |
|
|
683 |
</book> |
</book> |