SunPath v1.0
(c) 2005 by Peter Wienerroither, Austria
peter.wienerroither@univie.ac.at
http://mailbox.univie.ac.at/~pw/


My software SunPath illustrates the course of the sun. So you can show the path of the sun for one day for a specified date and so illustrate e.g. the suns path for the four seasons, as shown at my sample images, and that for any location on earth. But you also can show analemmas, the path of the sun over 1 year at always the same time. Very interesting are the suns paths at the extremes near the equator and near the poles, what also can be shown with this program.

After the installation and the start of the program you can see the main screen. On top is the menu, in the middle the graphics window and on bottom the fields for data input.
First you should activate the menu /File/New…/. Here you can specify the size of your image and the current image will be erased. All graphs will be printed one upon the other until you erase the screen with /File/New…/. Input the desired image width in pixels. ATTENTION: If the program now terminates, you don't have enough memory for the specified size of the graph. Restart the program and choose a smaller size of the image. The images height will be set automatically to half of the images width, because the images width corresponds to a 360° panorama and so the images height corresponds to +- 90° from the horizon (line in the middle) to the zenith. When you change the images size, the size of the main screen will not be changed, because the real image is calculated and drawn in the background and is available not until you save it as image file.

Next you should input the geogr. coordinates of your location. "Loc. Long." is the geogr. longitude in degrees. Enter it as decimal number and be aware to give locations east of Greenwich a positive sign and locations west of Greenwich a negative sign. "Loc. Lat." is the geogr. latitude. Enter it as decimal number and be aware to give locations north of the equator a positive sign and locations south of the equator a negative sign. At the menu /File/Save Options…/ you can save this geogr. data and the image size so they are available at the next start of the program.
Now you shold enter the date in the format jjjjmmdd and the starttime in the format hhmm. Be aware to input the time in UT (Universal Time) and not the local time.
Next you have to enter the time interval in hours (decimal number), that means the time interval between the calculated sun positions. And last the time duration in hours (decimal number), that means for how long the suns positions should be calculated. For the suns path for one day you should enter 0000 (0 o'clock) for time, i.e. 0.5 (1/2 hour) for interval and 24 for duration. For an analemma you should enter normally 1200 for time, 168 for interval (7 days) and 8760 for duration (1 year).
At last you can choose at "Animated" if the drawing should be done animated, that means with time delay so you can watch the sun moving.
Now click on "Draw!" to start the calculation and drawing of the graph or activate the menu /File/Draw the graph/.
You can repeat this procedure with different parameters as often as you want and all graphs will be painted on the same screen. If all selected graphs are on the screen, you should select the menu /File/Save As…/ to save the image in the selected size as bitmap. Now you can select the menu /File/New…/ to erase the current image and make a new one.

ATTENTION: The drawing of the graph is done in cylindric projection, so there are distortions near the zenith (top and bottom of the image). You can choose between cylindric projection and polar projection at the next release of the program.

You can end the program with the menu /File/Exit/.


NOTE:
The program SunPath is free for private and noncommercial use. If you want to use it commercialy, please contact me by e-mail so I can make you an offer. If you create photos with this program, you must add a note to the photo that it was made with this program!

Here the URL for download:
    http://homepage.univie.ac.at/~pw/pwcomswe.htm#SunPath


PW