<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:12pt"><div>Hi,</div><div><br></div><div style="color: rgb(0, 0, 0); font-size: 16px; font-family: 'times new roman', 'new york', times, serif; background-color: transparent; font-style: normal;">i wonder if there is a way in your shader to draw the solar disk too.</div><div style="color: rgb(0, 0, 0); font-size: 16px; font-family: 'times new roman', 'new york', times, serif; background-color: transparent; font-style: normal;">If we could sync the solar disk with the main sun lamp (for instance using this <a href="http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/3D_interaction/Sun_Position">http://wiki.blender.org/index.php/Extensions:2.6/Py/Scripts/3D_interaction/Sun_Position</a>), it would be perfect.</div><div style="color: rgb(0, 0, 0); font-size: 16px; font-family: 'times new roman', 'new york', times, serif;
background-color: transparent; font-style: normal;"><br></div><div style="color: rgb(0, 0, 0); font-size: 16px; font-family: 'times new roman', 'new york', times, serif; background-color: transparent; font-style: normal;">I dont look your code in details but martinsh ubris glsl code draw the sollar disk <a href="http://pastebin.com/c5g7TuiC">http://pastebin.com/c5g7TuiC</a></div><div style="color: rgb(0, 0, 0); font-size: 16px; font-family: 'times new roman', 'new york', times, serif; background-color: transparent; font-style: normal;"><br></div><div style="color: rgb(0, 0, 0); font-size: 16px; font-family: 'times new roman', 'new york', times, serif; background-color: transparent; font-style: normal;">Cheers</div><div style="color: rgb(0, 0, 0); font-size: 16px; font-family: 'times new roman', 'new york', times, serif; background-color: transparent; font-style: normal;">Tycho</div> <div style="font-size: 12pt; font-family: 'times new roman', 'new
york', times, serif;"> <div style="font-family: 'times new roman', 'new york', times, serif; font-size: 12pt;"> <div dir="ltr"> <hr size="1"> <font size="2" face="Arial"> <b><span style="font-weight:bold;">De :</span></b> Thomas Dinges <blender@dingto.org><br> <b><span style="font-weight: bold;">À :</span></b> Blender GSoC 2013 <soc-2013-dev@blender.org> <br> <b><span style="font-weight: bold;">Envoyé le :</span></b> Samedi 17 août 2013 0h23<br> <b><span style="font-weight: bold;">Objet :</span></b> [Soc-2013-dev] Weekly report #9 Cycles nodes<br> </font> </div> <div class="y_msg_container"><br>Hi,<br>here my week 9 report: <br><a href="http://wiki.blender.org/index.php/User:DingTo/GSoC_2013/Weekly_Reports/Week9" target="_blank">http://wiki.blender.org/index.php/User:DingTo/GSoC_2013/Weekly_Reports/Week9</a><br><br>Best to read it in the wiki, as there are lot of links.<br><br>= Week 9 =<br><br>== What I did this week
==<br>* I did some cleanup in the Cycles code this week in trunk. (Commit <br>59043, 59070, 59072...)<br><br>* Commited some motion blur code to my branch (r59183). We can now <br>enable/disable motion blur on a per object basis, inside the Properties <br>Editor. This commit also has some basic code for the motion multiplier, <br>but I still need to properly hook that up with the object transform <br>matrix and shutter time.<br><br>* I did some research on a new sky model this week. Cycles (as well as <br>Blender internal) use <br>[<a href="http://www.cs.utah.edu/~shirley/papers/sunsky/sunsky.pdf" target="_blank">http://www.cs.utah.edu/~shirley/papers/sunsky/sunsky.pdf </a>A Practical <br>Analytic Model for Daylight], but there is a better model available <br>since 2012. [<a href="http://cgg.mff.cuni.cz/projects/SkylightModelling/" target="_blank">http://cgg.mff.cuni.cz/projects/SkylightModelling/ </a>An <br>Analytic Model for Full Spectral Sky-Dome
Radiance]. The current <br>Preetham model suffers from some problems especially for sunset and <br>sunrise, which is better in the Hosek/Wilkie model. So I did some <br>research here, to check if a inclusion would be feasible.<br><br>Questions and observations<br><br>The current model gets calculated within Cycles itself.<br><br>SVM: Pre-calculation in nodes.cpp, final evaluation in the SVM file.<br><br>OSL: Has everything in the .osl file, but as the sun_direction and <br>turbidity is constant, it can only calculate that once and optimize it <br>out then for the actual rendering. (OSL makes heavy use of constant <br>folding etc.)<br><br>The new model on the other hand comes with a 66kb large dataset with <br>values (ArHosekSkyModelData_RGB.h). (See <br>[<a href="http://cgg.mff.cuni.cz/projects/SkylightModelling/HosekWilkie_SkylightModel_C_Source.1.4a.zip"
target="_blank">http://cgg.mff.cuni.cz/projects/SkylightModelling/HosekWilkie_SkylightModel_C_Source.1.4a.zip </a><br>Sample code archive].)<br>Other engines all use this data, so I guess we need it too. But I guess <br>we should use that to precalc the sky again, and not increase kernel <br>size. What confuses me is that "ArHosekSkyModelState" which we need to <br>initialize. (As we use RGB, we would start with <br>"arhosek_rgb_skymodelstate_alloc_init").<br><br>I checked on some implementations of the new model.<br>* [<a href="https://github.com/githole/Skydome/blob/master/skydome.c" target="_blank">https://github.com/githole/Skydome/blob/master/skydome.c </a>Simple <br>implementation] which calculates every pixel and outputs an image.<br>* Mitsuba renders the Sky to an HDR map internally and uses this.<br><br>So basically I would appreciate some starting points on how to approach <br>this. Use the model data? Separate code into precalc and svm
evaluation <br>again?<br><br>== Next week ==<br>* Continue with the Sky feature. I would also like to spend some time <br>documenting some of Cycles code, which is not so trivial to understand <br>(at least for me). :)<br><br>== Questions ==<br>See above, regarding the new Sky model.<br><br>Best regards,<br>Thomas<br><br>-- <br>Thomas Dinges<br>Blender Developer, Artist and Musician<br><br>www.dingto.org<br><br>_______________________________________________<br>Soc-2013-dev mailing list<br><a ymailto="mailto:Soc-2013-dev@blender.org" href="mailto:Soc-2013-dev@blender.org">Soc-2013-dev@blender.org</a><br><a href="http://lists.blender.org/mailman/listinfo/soc-2013-dev" target="_blank">http://lists.blender.org/mailman/listinfo/soc-2013-dev</a><br><br><br></div> </div> </div> </div></body></html>