(11-01-2021, 04:40 AM)samsepi0l Wrote: [ -> ]Switching gears - has anyone ever made a PCX image "how to guide" for SGE? I am getting started on Denver tonight! I want to make sure I am happy with the SG file first. I am nervous because there are A LOT of buildings!

Here's how I did it for Nashville and Detroit.

1) First step, go to Google Maps, take some screenshots and stitch together a good aerial view. Be sure North is up (i.e. don't rotate the map)! I would go no more than 3000px wide (or tall) otherwise it won't open in SGE/SFE. Save a master copy of it, and then try to make a higher contrast, grayscale version of it before exporting it to .PCX.

2) Now you need to make some measurements. I take the aerial image and draw a straight line between two points, as far away from each other as possible, but easy enough to find. Record how many pixels is the length of the line.

3) Go to Google Earth. Use the Path tool to draw the exact line you drew in Step 2 and find out how many feet are between the two points.

4) You can now use math to determine how many "feet per pixel" is the scale of the aerial photo. Convert that to 500ths by multiplying feet by 6000.

5) Open SGE.INI. There is a section for you to modify:

PCX = detroit3.pcx

PCX PIXEL SIZE = 8790.2548

PCX UPPERLEFT = -13185382 8882552

In the above example, I determined that each pixel represents 1.465 real-world feet, or 8790.2548 "500ths", so that goes under PCX PIXEL SIZE.

Now for PCX UPPERLEFT, that is the x and y coordinates in your ICR2 track that correlate to the location at the upper left corner of your PCX file. What I've done to get to this number is, I figure out based on the width and height of my aerial photo, the distance that my aerial photo covers (i.e. in 500ths). At this point, I like to center my PCX so I shift it to the left (hence the negative x value which represents about half the distance covered by the photo, and the positive y value which is the distance if you shift the PCX file "north").

Having "calibrated" my PCX file, then anything you do in SGE will be at the real world scale already. I also have a spreadsheet set up for Detroit and Nashville that converts latitude and longitude to the x, y coordinates of the ICR2 track (and this is also why it's important that your aerial photo is aligned to the compass).

As an aside, very glad to hear you starting work on Denver! This along with Detroit will complete the 1990 season.