June 14, 2023
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I migrated this appllication to GTK3 from the old GTK2 routines so that it would be slightly more
modernized. The original code is almost 20 years old, so was very depcreated, and this should future
proof it a little more. The biggest change necessary was converting the bit-order of the colormaps
that are used to draw the flame effect and the draw_fire() function for Cairo. Cairo's RGB-24 format
needs the most-significant 8 bits of the integer to be unused, with the second-most significant
byte to be the R value, then G and B. This meant the colormaps needed to be converted to new encoding
and also that the old MSB-order maps can be used as new colors.
