Left click a mouse and move it to rotate the object, normally in an intuitive
way: it is as if you touch a ball an spin it. This way isn't implemented all
the way through though, since I also wanted that if you return to your
starting point and release the object should have its original orientation.
It is also possible to rotate the object around an axis that sticks out of the
canvas. This can be done by clicking and dragging along the edges of the
Because I also wanted the object to get back to its initial position
when releasing it at the same spot, some strange effects can be seen when
taking up the object in the centre of the canvas (by clicking) move it to a
side, rotate it 180 degrees around an axis orthogonal to the canvas and then
drag it back to the centre of the canvas.
Zooming can be done by pressing the shift and using the main mouse-click.
Undo zoom and rotate (original position): '5'.
Undo zoom only: shift-5.
Undo rotate only: alt-5.
The mouse wheel works for zooming as well, but the speed might be low.
By default concave polygons are supported by means of a stencil buffer. This
means that two passes are required and all faces need to be considered
separately. This isn't very efficient, so there is a way to optimise this for
objects that only have convex faces: The key 'c' is used to toggle support for
concave and convex faces.
Navigation by Touch Screen
The following actions are support for touch screen:
Rotate: single touch and drag. The rotation axis is defined in the same
way as for the mouse. See previous section.
Zoom in: double touch and increase distance between the two fingers.
Zoom out: double touch and decrease distance between the two fingers.
Jump back to original orientation: triple touch.
Show an Off-File from this Website
To show any off-file that is part of this domain add to the URL the string
"?off_file=<URL>", where <URL> is the complete URL to the
off-file, e.g. add
security reasons cross-origin requests are blocked, meaning that you only can
do this for off-files with the exact same domain name as the base URL.
Set the Default Camera Distance
The default camera distance is set to 10. If you want another distance, e.g.
7, then you can specify this on the URL by adding "?distance=7" to the URL. If
you use more then one parameter, then you will need to split them by '&'
(and only use the '?' at the start of the parameters), try for instance:
Set Whether to Use the Stencil Buffer
Non-concave faces should be drawn by using the a stencil buffer. By default
this is turned of when loading objects through URL. This can be enabled by
adding "&stencil=true", e.g. for
Set Background Colour
You can set the background colour by setting the parameter "&bg_col=0xrrggbb"
where 0xrrggbb is a hexidecimal number for the red (rr), green (gg) and blue
(bb) chanals. E.g. for