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    <p><b style="font-weight:normal;"
        id="docs-internal-guid-820867b0-8a8c-2d0c-ab73-821d7696a459">
        <h1 dir="ltr"
          style="line-height:1.38;margin-top:20pt;margin-bottom:6pt;"><span style="font-size:20pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">Weekly Report #09 - Silhouette Operator</span></h1>
        <br>
        <p dir="ltr"
          style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">The second evaluation is now done. That means only one month left to finish the Silhouette Operator! Judging by the rate of progress I will not be able to implement all the features and ideas I had within the Gsoc timeframe. Nevertheless achieving the number one goal: “Giving the sculptor the freedom to add new geometry contrary to just shaping the existing” is definitely within reach. </span></p>
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        <p dir="ltr"
          style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:700;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">What has been done this week?</span></p>
        <p dir="ltr"
          style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">This week i started to finish the geometry generation by adding code to generate backsides as well. Now generating a silhouette creates a waterproof shape with the configured settings. I created a small video to demonstrate the impact of the different settings. You can find it here for now: </span><a
href="https://www.dropbox.com/s/x12a62zf2ynevum/Basic_002_fs.mp4?dl=0"
            style="text-decoration:none;"><span style="font-size:11pt;font-family:Arial;color:#1155cc;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:underline;vertical-align:baseline;white-space:pre-wrap;">https://www.dropbox.com/s/x12a62zf2ynevum/Basic_002_fs.mp4?dl=0</span><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">

</span></a></p>
        <p dir="ltr"
          style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">In the second half of the week I started with the next big step: Connecting new silhouettes to existing geometry.</span></p>
        <p dir="ltr"
          style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">This poses a challenge for multiple reasons:</span></p>
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          <li dir="ltr"
style="list-style-type:disc;font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;">
            <p dir="ltr"
              style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">The intersection of both, the silhouette and the old geometry needs to be calculated. Depending on the geometry complexity this is really computational heavy.</span></p>
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          <li dir="ltr"
style="list-style-type:disc;font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;">
            <p dir="ltr"
              style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">The transition between the two shapes can be rather complex because minimal assumptions can be made about both shapes.</span></p>
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          <li dir="ltr"
style="list-style-type:disc;font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;">
            <p dir="ltr"
              style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">The topology of the transition is not trivial. Depending on the existing topology many different factors need to be taken into account. Vertex density, edge/loop flow orientation and varying face sizes or even ngons. </span></p>
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        </ul>
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        <p dir="ltr"
          style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">For the transition between the two shapes i decided to go with a more practical than precise approach. CAD-style precision is not the goal of the tool. Moreso the tool is supposed to give the artist the option to get a quick basemesh to start sculpting on. -Not a perfect shape.</span></p>
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        <p dir="ltr"
          style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">I was able to get a good start tackling the first challenging factor. I reduced the intersection problem to a 2D-Polygon point intersection task. It is fast but gives inaccurate results if the shape in the z-axis is not primitive as is the case if smoothness is close to 1. But in practice this is a reasonable drawback to take. If the smoothness factor is high, the transition between the silhouette and old geometry is supposed to be blurred and smooth anyways. I finished detecting interior vertices and I am currently in the process to find the necessary edges and loops which will later be deleted and/or connected.</span></p>
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        <p dir="ltr"
          style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">Looking forward to the next week,</span></p>
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        <p dir="ltr"
          style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;"><span style="font-size:11pt;font-family:Arial;color:#000000;background-color:transparent;font-weight:400;font-style:normal;font-variant:normal;text-decoration:none;vertical-align:baseline;white-space:pre-wrap;">Sebastian Witt</span></p>
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