The JPEG quality factor
describes how much details you are willing to lose in the JPEG
compression. With the highest quality (100), the saved image should be
the same quality as the map window image.
Higher quality is not
the same as higher resolution, which says that you want an image with a
lot more pixels in it, so you can zoom in and see more details. Higher resolution is available to you when you click the
"Options" button when you save the map window to any image format. For
historic reasons this option was implemented in the GISDK by folding it
into the image quality option for all image formats, but using the
Quality number as a negative number.
For example
SaveMapToImage(, "c:\\Image.png",
"PNG", {{"Quality", -200}})
will save the current map image with 200
dpi.
Two notes:
1. This is an undocumented usage of the
"Quality" option, it is slated to be replaced by a "Resolution" option.
2. The allowable dpi values depend on your
screen resolution, graphics card and memory.
-Kjartan
