PTStitcher will output a wide variety of
projection formats, however
PTViewer generally uses only two; equirectangular and rectilinear.
|| Projection format
(full or partial)
One of the most common faults/queries relates to cylindrical panoramas.
Cylindrical panoramas need to be
converted to equirectangular
to be displayed properly.
PTViewer uses two types of coordinates, absolute and relative.
Absolute coordinates are measured in pixels and measured from the top,
right corner of the image.
Relative coordinates are measured in percentages from the top right
corner of the complete 360x180° image. Confusion can arise with partial
panoramas, where the edge of the image is not defined by 0/100%. PTViewer
currently does not correctly display the relative coordinates for partial
panoramas. You can calculate relative coordinates from absolute coordinates
by calculating the distance of the coordinates from the centre of the image,
converting them to percentages and adding this to 50% (the centre of an
image is X50,Y50)
x,y - absolute coordinates
X,Y - relative coordinates
w - width of the image (pixels)
h - height of the image (pixels)
pfov - horizontal FOV of the image
X = 50 + (x - w/2) * (pfov/3.6w)
Y = 50 + (y - h/2) * (pfov/3.6w)
Why use relative coordinates?
Relative coordinates are useful if you need to develop a tour at
different resolutions for different uses (e.g. low resolution for web plus
high resolution for CD). Altering the size of the panorama images will then
have no effect on the positioning of the coordinates. You can simply
swap the panorama images of different sizes and everything should still