Changes between Version 4 and Version 5 of Help/Plugin/PicLayer

Timestamp:

2010-10-10T22:58:47+02:00 (15 years ago)

Author:

anonymous

Comment:

--

Help/Plugin/PicLayer

@@ -37 +37 @@
 
 
-For those interested in converting calibration data in PicLayer:
-
-INITIAL_SCALE is the initial size of 100 image pixels (length of ruler in JOSM).
-
-SCALEX/Y is the factor after changing the size of the raster image relative to JOSM data layer.
-
-INITIAL_POS_y/X are the coordinates of the image center in mercator projection.
-
-POSITION_X/Y are the coordinates after shifting the raster image relative to JOSM data layer.
-
-ANGLE is the angle in degrees (clockwise -> positive) when the raster image is rotated.
-
-Mercator units are arc units in longitude (PI <-> 180).
-
-Latitude is a bit complicated because this projection preserves angles but not areas:
-y = ln(tan(45+b/2))
-where b is in degrees, ln ist the natural logarithm and tan ist the tangent.
-
-The longitude in degrees l is obtained from x via l = x*180/PI.
-
-The latitude b can be calculated from y by b = 2*arctan(e power y) - 45 (when inverse tangent returns degrees).
-
-When transforming longitude degree differences of image corners to distance, you have to take into account that one degree east-west has different size dependent on latitude.
-
+For those interested in converting calibration data in PicLayer:[[BR]]
+INITIAL_SCALE is the initial size of 100 image pixels (length of ruler in JOSM).[[BR]]
+SCALEX/Y is the factor after changing the size of the raster image relative to JOSM data layer.[[BR]]
+INITIAL_POS_y/X are the coordinates of the image center in mercator projection.[[BR]]
+POSITION_X/Y are the coordinates after shifting the raster image relative to JOSM data layer.[[BR]]
+ANGLE is the angle in degrees (clockwise -> positive) when the raster image is rotated.[[BR]]
+Mercator units are arc units in longitude (PI <-> 180).[[BR]]
+Latitude is a bit complicated because this projection preserves angles but not areas:[[BR]]
+y = ln(tan(45+b/2))[[BR]]
+where b is in degrees, ln ist the natural logarithm and tan ist the tangent.[[BR]]
+The longitude in degrees l is obtained from x via l = x*180/PI.[[BR]]
+The latitude b can be calculated from y by b = 2*arctan(e!**y) - 45 (when inverse tangent returns degrees).[[BR]]
+When transforming longitude degree differences of image corners to distance, you have to take into account that one degree east-west has different size dependent on latitude.[[BR]]
 At equator 1 degree -> d0 = 111.3 km, at latitude b you get d = d0/cos(b)(only exact for sphere, but deviation from ellipsoid < 0.5%).