SkyMap Release History ---------------------- 27-DEC-93 v2.0 Major release. A total rewrite of the program to make it much faster and to dramatically improve the user interface. Many new features added including display of comets. 10-Sep-93 v1.33 Bug-fix release: Images of RNGC objects couldn't be displayed automatically on a horizon map, because I'd forgotten to add the line of code to do so! Fixed. 25-Aug-93 v1.32 Bug-fix release: An error in the floating point emulation libraries of Microsoft's Visual C++ compiler, causing the "tan" function to return the wrong sign, was resulting in the effects of refraction being applied in reverse on some machines without a maths co-processor. Applied a "work around". The colour of RNGC objects and their labels was defaulting to black on the horizon map. This was difficult to see against the black map background! 04-Jul-94 v1.31 Minor bug fix release: It wasn't possible to save a configuration in which the faintest stars were drawn as a single pixel. Single pixel stars were replaced by 4-pixel stars by over-zealous error checking code when the configuration was reloaded. RNGC objects on the Area map were being incorrectly drawn and labelled using the star, rather than the RNGC object colours. An extra line connecting the two halves of the constellation "Serpens" was being drawn on the constellation outlines, because the drawing code regarded Serpens as a single constellation whose points were to be connected. Fixed by treating the two halves of Serpens as two separate constellations as far as the outline drawing code is concerned. 29-May-93 v1.3 New features: The program can now display non-stellar objects. The database used is the Revised New General Catalogue (RNGC). Constellation boundaries can now be displayed. The printing options have been greatly expanded. When a map is printed the user can now select whether to print the entire map, or the current zoomed view, and also whether to print in black and white or colour. For colour maps a dialog allows the user to select the colour of each component of the map. All map features are now present on both the horizon and sky area maps (eg star labels can now be displayed on the horizon map). The user interface has been made more consistent between the map types. The program now has an optional ToolBar at the top of the screen, which provides short-cuts for the commands on the "View" menu. The program now (finally!) has a complete on-line help system. This is basically a copy of the manual. Bug fixes: I'd forgotten to apply the correction for diurnal parallax to planetary positions on the Sky Area map. Consequently, the planets were being shown in their geocentric, rather than topocentric positions, resulting in errors of up to 2 degrees in the apparent position of the Moon. Fixed. The size of the image of the Sun and Moon on the Sky Area map was being incorrectly calculated, resulting in images that were about 50% too large when the map was printed on a portrait orientation page. Fixed. 07-Mar-93 v1.2 New features: Added a new "Sky Area" map type, centred on a right ascension and declination. This is intended to be used to draw a detailed map of a small region of the sky. Added the ability to display photographic images in either GIF or BMP format. Images can either be explicitly opened, or associated with specific objects (currently planets) and automatically displayed. Bugs fixed: Single pixel stars were being printed on the printer in the screen colour, which almost certainly mapped to white on the printer, resulting in them not being printed. On a mono print, single pixel stars are now correctly printed black. When the right mouse button was pressed over a horizon map to display the pop-up menu, then the *right*, rather than the *left* button pressed (ie, a user input error!) an incorrect cursor position was stored. If the left button was subsequently used to select an information dialog a wildly inaccurate position or a GPF resulted. This is probably the cause of all the "random number" errors previously reported. Thanks to Don Munro for tracking down a reproducable case of this puzzling error! Fixed. Removed the incorrect, uninitialized data displayed on the information dialogs for the Sun and Moon. (Eg phase 0.000 for the Sun.) 05-Feb-93 v1.11 When the start of a constellation figure was off the edge of the map, the first visible line of the constellation was being drawn incorrectly in certain circumstances. Fixed. The correction for refraction was being correctly calculated and correctly displayed in the "About" box for a star, but not applied to the plotted position of the stars on the map. This led to stars being plotted with slightly too low an altitude (the maximum error being about half a degree at the horizon). Fixed. If the star position calculation was aborted by the user pressing the "Cancel" button, the subsequent constellation figure setup calculation code displayed an error message for each star it was unable to find. Pressing the "Cancel" button now aborts the map calculation cleanly. 31-Jan-93 v1.1 Test release to BIX only for testing. In the "Observer" dialog, the "Time Difference" edit field was only wide enough to allow two digits to be entered, making the program not too useful for anyone outside the GMT time zone. Fixed. Version 1.0 of SkyMap simply plotted stars in their mean catalog position. This version now rigorously calculates the apparent place for the time of observation, correcting for proper motion, aberration, precession, nutation, and refraction. Added code to verify that dates are in the range 4000BC-8000AD (the range over which the planetary position equations are valid. 24-Jan-93 v1.0 Release of SkyMap 1.0, with basic facilities for drawing horizon map and plotting planetary and lunar positions.