Mar 26 2001: Changes in drawmap between version 2.3 and version 2.4: + Drawmap can now handle DEM files with elevations in feet. + Some clarifications have been added to the manual page, including an example of the use of GTOPO30 files. + There is some additional installation information in the README file. Jan 16 2001: Changes in drawmap between version 2.2 and version 2.3: + This point release is partly the result of downloading more test data for more parts of the USA, and fixing whatever new problems might show up. There are, however, several new options and general modifications, and also a few bug fixes. These are described below, although some of the minor bug fixes are omitted. + Added the -r option to allow the sharpness of the shaded relief to be varied. The default is fully-shaded relief, which was the only available shading in previous releases. The new option allows the darkness of shadows to be reduced, in steps, until all shading disappears and only simple color bands remain. + Added the -z option, which adjusts the color table so that it exactly spans the range of elevations in the given data. This ensures that all available colors are used in the map; but at the cost of having each color represent a peculiar range of elevations. + Added the -m option, which allows limited enhancement of light/dark shading in shaded-relief maps. + Added the -t option, to shut off generation of tick marks and latitude/longitude markings. + In response to a request, added the -C option, which works the same as the -c option, except that it fills in the space between contour lines with solid colors. + In past releases, the -c option located contour lines in the centers of the elevation bands. In other words, if the contour interval was 100 meters, then the first contour would be at 50 meters, with the next at 150 meters. In this release the code has been modified so that contour lines are on the edges of the elevation bands. In other words, if the contour interval is 100 meters, then the contours are at 100 meters, 200 meters, and so on. + A few of the GTOPO30 files were rejected because quantization error caused some consistency checking to fail. Loosened up the checks slightly so that the files now pass muster. + Updated the color scheme for drawing DLG vector data. Changed railroads and pipelines to black, and changed vegetative features to green. + Added support for more attribute types, including 190/UNPAVED. Fixed a few attributes that have special cases, such as range and township numbers that can take forms like "10 1/2E". + Some USGS SDTS DLG files have attributes whose record IDs double back and duplicate other record IDs in the file. (Wilmington Delaware 24K DLG HY 1379127.HY.sdts.tar.gz and 1379151.HY.sdts.tar.gz are examples.) I would guess that this is a bug in the SDTS files, since it would leave no way to distinguish between attributes. (One could use the record number in the ISO 8211 header, but I don't think this is considered legitimate under the standard.) One way or the other, this was causing drawmap some indigestion, so the software has been fixed to deal with the problem as best it can. Drawmap prints a warning message when this situation occurs. + Beefed up the test program, tacked onto the end of sdts_utils.c, so that it is a useful viewing tool for SDTS files. Aug 1 2000: Changes in drawmap between version 2.1 and version 2.2: + Added the sdts2dem and sdts2dlg programs to convert SDTS transfers into the `classic' DEM and `optional' DLG formats. I wrote these primarily to allow me to test drawmap's SDTS capabilities, but they should be generally useful. + Improved the handling of SDTS files. In particular, we no longer ignore some of the minor attribute files, so all attributes should be included. Improved the handling of attributes overall. This includes specific support for attributes with special needs. + There were a number of minor repairs and upgrades here and there. + Decreased the default memory footprint a bit, by changing some long variables to shorts in some of the larger arrays. Unfortunately, new feature development probably devoured a lot of these savings. + Modified the -h option to automatically include a blue surface at sea level. + Modified the -i option to include the DLG name, and the type of data in the file, when printing info about DLG files. Jul 23 2000: Changes in drawmap between version 2.0 and version 2.1: + Added support for the NAD-83 datum and the WGS-84 datum. + Drawmap can now read SDTS-format DEM and DLG files. + At the request of a drawmap user, I added GTOPO30 files to the set of files drawmap can read. This should provide at least some map-drawing capability for people who can't get DEM data for their countries of interest. + There were a number of minor repairs and upgrades here and there. + Changed the names of block_dem and block_dlg to unblock_dem and unblock_dlg so that they are consistent with the equivalent "dd" commands. Jul 8 2000: Changes in drawmap between version 1.10 and version 2.0: + This was a fairly major restructuring of drawmap, mainly to get it to handle DEM and DLG data at the 7.5-minute resolution. + In past versions of drawmap, data smoothing was done when the image resolution and data resolution were the same. This version of drawmap no longer smooths when the source data and target image have close to the same resolution. In addition, the code implementing smoothing has been clarified, so that the smoothing behavior should be easier to understand and modify. + Restructured the shaded relief code to allow it to handle data from DEMs in various resolutions. Also moved most of the color definitions into colors.h so that users can more easily modify the color scheme. Provided four separate color map tables, selectable by the "-n" option, so that users can choose between a variety of color schemes. "Natural" colors are now the default, rather than the garish high-perception colors used in previous versions. Also toned down the red and blue that are used to draw streams and roads. They were a bit distracting. + Added a new "-w" option to allow flat sea-level areas to be automatically colored blue. + Removed the requirement that the x and y dimensions be even. This was done primarily because 7.5-minute DEMs often have odd dimensions. + Drawmap no longer tries to create an image file until after most error checking is done. This should reduce the incidence of half-created image files being left behind after an error. + Drawmap now uses Redfearn's formulas to convert UTM coordinates to latitude/longitude coordinates and vice versa. However, the program still uses linear interpolation from the corners of the data blocks to transfer DEM data into the map image. + There are two new stand-alone commands, utm2ll and ll2utm that convert latitude/longitude coordinates to UTM coordinates and vice versa. They currently only support the NAD-27 datum, but can be easily modified to use others. + The dem_dlg_info program has been deleted. It is replaced by the "-i" option to drawmap. + The height-field program in the height_field subdirectory has been deleted. It is replaced by the "-h" option to drawmap. The code that tried to generate "povray" objects for roads, lakes, towns, and so on, is no longer present in any form. It produced crude results and didn't seem very useful. Jun 18 2000: Changes in drawmap between version 1.9 and version 1.10: + The USGS has changed the format of both types of GNIS files. Modified drawmap to handle the new formats. NOTE: Files in the old formats will no longer work. + Cleaned up a few minor things here and there. Jun 3 2000: Changes in drawmap between version 1.8 and version 1.9: + Some of the newer USGS 100K DLG files contain newlines. (Older ones did not.) Modified drawmap to handle this new wrinkle. + Provided a new program called dem_dlg_info, to print out some useful information from the headers of DEM and DLG files. + Dropped the block_std program, since standard-format files have disappeared from the USGS web site. + Added manual pages for block_opt and dem_dlg_info. Jan 3 2000: Changes in drawmap between version 1.7 and version 1.8: + Clarified the code comments and the manual page for drawmap. + Included the povray_height_field directory, which contains a modified version of drawmap that will produce information that the ``povray'' package can use to make 3-dimensional renderings of terrain. + There were no changes in the operation of drawmap --- only changes in the code comments. The primary purpose of this release was to add the drawmap_height_field program. Jan 16 1999: Changes in drawmap between version 1.6 and version 1.7: + removed restrictions on the size of contouring intervals + added code to allow use on big-endian machines + added gaussian smoothing for oversampled maps to reduce checkerboard effect + changed DLG line-drawing algorithm to produce better map registration + changed drawmap and llsearch to handle the new GNIS format Dec 11 1998: Changes in drawmap between version 1.3 and version 1.6: + Fixed a portability bug, and an obscure bug in the code that draws tick marks at the edges of the image. + Added some new information about licensing (see the file "COPYING_NOTE"). + Added a new option "-c", that draws contour lines instead of the normal shaded relief. Oct 12 1998: Changes in drawmap between version 1.3 and version 1.5 (there was no version 1.4): + Fixed a portability bug, and an obscure bug in the code that draws tick marks at the edges of the image. + Added some new information about licensing (see the file "COPYING_NOTE"). + Added a new option "-c", that draws contour lines instead of the normal shaded relief.
