#668 "Sky" rendering - distance to horizon

[OK Hoff]

I like to have an inkling of what I can see out the window (my two projects are rural) and prefer to avoid the horizontal border between sky and ground. Therefor I often add a modified panorama treeline.
1) But the horizon is still very far away - could it move closer (without ruining something),
2) and in the photo rendering, the viewing angle of the background is different.

None of this important - more of a thought if you wish to work on a room with a view...

ok

[OK Hoff]

Here is an example that may be easier to see. Not something I worry about, I just happened to come across a better example. The mountains are higher in the rendered view. But then, I guess the sky texture was never really intended for this use... ok

[OK Hoff]

And on a grid.

[OK Hoff]

Oops - one horizontal line too many - this is 360° × 90° grid to illustrate sky-texture. And to align a distant (typically alpine) panorama to the sky-texture. The red line is where the image starts (to the right, East if compass is due North) and where the panorama needs to be seamless. ok

[OK Hoff]

With winter/summer solstice sun path
Examples from forum:
http://sweethome3d.com/support/forum/viewthread_thread,7182
And 3D view:
http://www.sweethome3d.com/viewHome.jsp?id=261

[OK Hoff]

Illustration images. Simple grid and late October rendering at 60° North (sun should be some 18° above the horizon). Does the vertical scale look about right? Just trying to find a good template.

[OK Hoff]

After posting in forum thread 8832, it dawned on me that for the 3D view it may be as simple as using the sine of the angle to calculate hight of each horizontal line. Being mathematically challenged, this may be totally wrong, but it looks a lot better (in the 3D view - not sure about the rendering).

Inkscape compatable: pan360.svg (links to pan360.jpg in same directory) for scaling.
pan360.jpg
Test rendering using the above as sky texture (svg converted to png).

ok

[Emmanuel Puybaret]

The sine was already used to compute the coordinates of the sky sphere, but I shouldn't have used sine again for the texture mapping! Anyway, tanks for the suggestion even if the fix is actually the reverse of your suggestion, since I removed some calls to Math.sin! ;-)

[OK Hoff]

THANK YOU. Actually, my sine experiment was intended for the 3D view, but now it matches rendering equally spaced altitude lines gives just the kind of view I wish for. This will be very useful as I will describe in forum thread 8832. Only thing I miss, is the possibility to set the starting point of the texture.

ok

Some tests and sky element files (relative links from the adjusted SVG) enclosed.

[OK Hoff]

A couple of more elements, to be elaborated (but probably not under feature requests :-) ).

[OK Hoff]

And output.

[OK Hoff]

And in a file with embedded elements as a demo - fil < 50 KB, but scales well. ok