<div dir="ltr"><div>Hi Alexander,<br><br></div>Yes, what you pointed out definitely needs to be corrected. Also, the constellation image moves when you pan the sky. I am not sure on an exact mathematical solution to the problem. So what I have done is that I looked up the coordinates for the midpoint of the image from Stellarium, and adjusted the size of the image and position angle in order to best fit the constellation lines. Now as it turns out, these values are not the same for all projection systems. <br><br><div>I have tried to implement a completely new method, that fixes the 4 corners of the rectangle in the sky, but it draws the image in a very weird manner. The image is stretched and drawn outside the sphere. I have tried to do this on Ursa Major. Could you perhaps suggest some ideas to solve this problem or maybe some ideas to modify the old code itself?<br><br></div><div>Thanks.<br></div><div><br></div></div><div class="gmail_extra"><br clear="all"><div><div class="gmail_signature"><div dir="ltr"><div><div>M.S.Adityan</div><div dir="ltr">Website: <a href="http://www.msadityan.com" target="_blank">www.msadityan.com</a><div><a href="https://www.linkedin.com/in/msadityan" target="_blank">https://www.linkedin.com/in/msadityan</a><br></div></div></div></div></div></div>
<br><div class="gmail_quote">On Tue, Jul 21, 2015 at 10:36 PM, M.S. Adityan <span dir="ltr"><<a href="mailto:msadityan@gmail.com" target="_blank">msadityan@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div><div><div><div><div><div>Hi,<br><br></div>Here are a few proposed ideas to solve the clipping problem with constellation art.<br><br></div>1. Draw a opaque black rectangle with a hollow center for the sphere. This black rectangle will cover any 'part' of the constellation image that is drawn beyond the sphere.<br><br></div>2. Note down the coordinates of the 4 corners of the rectangle for each constellation image. Then draw the image ONLY if all the 4 corners are visible on the sky. This will ensure that the image is drawn only if the entire rectangle lies on the sky.<br><br></div>3. The clipping happens when FOV>180. So we get FOV center() and then find the minimum and maximum values by adding or subtracting 90 from it. Then check the midpoint Aziumth and add the width of the constellation image in degrees to it. If this value is greater than fov_center+90 or less than fov_center-90 then it needs to be clipped. <br><br></div>Can anyone help solve this issue? <br><br></div>Thanks.<br></div><div class="gmail_extra"><br clear="all"><div><div><div dir="ltr"><div><div>M.S.Adityan</div><div dir="ltr">Website: <a href="http://www.msadityan.com" target="_blank">www.msadityan.com</a><div><a href="https://www.linkedin.com/in/msadityan" target="_blank">https://www.linkedin.com/in/msadityan</a><br></div></div></div></div></div></div>
<br><div class="gmail_quote"><span class="">On Sat, Jul 18, 2015 at 5:30 PM, <span dir="ltr"><<a href="mailto:kstars-devel-request@kde.org" target="_blank">kstars-devel-request@kde.org</a>></span> wrote:<br></span><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><span class="">Send Kstars-devel mailing list submissions to<br></span>
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Today's Topics:<br>
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1. Clipping artwork on the border of skymap (M.S. Adityan)<br>
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Message: 1<br>
Date: Fri, 17 Jul 2015 21:25:01 +0530<br></span>
From: "M.S. Adityan" <<a href="mailto:msadityan@gmail.com" target="_blank">msadityan@gmail.com</a>><br>
To: KStars Development Mailing List <<a href="mailto:kstars-devel@kde.org" target="_blank">kstars-devel@kde.org</a>><span class=""><br>
Subject: [Kstars-devel] Clipping artwork on the border of skymap<br>
Message-ID:<br></span>
<CA+T53Rq-pXzfJeetiDbsyw3K=k22FaOBBHOxKRp8gqC6w-v=<a href="mailto:3w@mail.gmail.com" target="_blank">3w@mail.gmail.com</a>><span class=""><br>
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<br>
Hi,<br>
<br>
I have completed Western and Inuit sky culture artwork in KStars. The<br>
artwork is currently displaying completely on the border of the sky map. I<br>
want to make it clip such that it displays only the portion of the artwork<br>
which is "on" the sky map and not the one that goes out of the sphere. How<br>
can this be achieved? To see how KStars looks currently please see this<br></span>
<<a href="http://www.msadityan.com/wp-content/uploads/2015/07/kstars.png" rel="noreferrer" target="_blank">http://www.msadityan.com/wp-content/uploads/2015/07/kstars.png</a>>.<span class=""><br>
<br>
Also another issue was regarding pixelation of the artwork at high zoom<br>
levels. To solve this, I scaled every constellation image to 1024x1024<br>
pixels using Qt::SmoothTransformation. Is this a right way to solve the<br>
problem? (please refer to the latest git commit on<br>
gsoc2015-constellationart branch for this)<br>
<br>
Regards<br>
M.S.Adityan<br></span>
Website: <a href="http://www.msadityan.com" rel="noreferrer" target="_blank">www.msadityan.com</a><br>
<a href="https://www.linkedin.com/in/msadityan" rel="noreferrer" target="_blank">https://www.linkedin.com/in/msadityan</a><span class=""><br>
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