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   The rendering today has the addition of a rolltop desk.  I had finished the bottom part of the desk yesterday evening, but still needed the top.  After I placed it in the scene, I found it rendered rather dark.  So I added a desk lamp.  It also dawned on me that Kerkythea also has settings for the camera lens.  By default Kerkythea shoots with a 46 mm focal length.  My room is small, so I want a wider view.  So I changed the lens to a 20 mm focal length.  This results in putting much more into the frame.  I darkened the ceiling as the tin was looking more like brass.
   This render is 9 iterations taking over 15 hours to complete.  I don't like the desk lamp shade, which rendered better when up close.  All the lights are too bright.  And I think 20 mm is too wide an angle.  However, I think the ceiling is more accurate though, and the desk if pretty convincing.  Sketchup tells me this model contains 199,016 edges, and 92,236 faces—it's starting to get complex.
   Changes for the rending today include a tin ceiling, the selection of an actual Victorian wallpaper pattern, and the use of different types of wood for the various wood items.  I also fixed the strange light stripe caused when I turned the bulb on in the bottom of the parlor lamp.  Turns out the index of refraction value messes up everything.  I left it out of the equation and everything works better now.
   This rendering has 14 iterations and took 8 hours and 13 minutes.
   This rendering is a 23 iterations at a resolution of 2816x2112 taking 13 hours, 35 minutes, and 34 seconds on my 2.5 GHz quad-core.  You really do have to look at a large version of this image in order to appreciate the detail.  Improvements over yesterday's rendering include the addition of a door knob, wall lamps, and the removal of the strange texture on the walls.
   While rendering I noticed the ceiling was not what I had hoped for.  I drew a new tin ceiling and played some with the material, but I did not want to stop the progress on the rending to use the new model.
   I am pretty happy with this rendering and it is time to add more furniture.
   I have been doing a lot of work trying to get a good stained glass material, and I can usually get the results I am looking for.  However, I can not seem to do it by the physics of stained glass.  Lead glass has a higher index of refraction then standard glass, but if I set this value my glass no longer works.  I also did some experiments with glass having thickness vs glass without thickness.  Having thickness often resulted in no transparency to the glass.  Until I understand Kerkythea better I will have to continue to cheat and use glass that has no thickness.
   My goal of building lamps was to start to render a room.  So far I had lamps and a mirror.  I have light.  Now it is time to work on the room.  I wanted an antique table.  As I discovered, making the legs I wanted my table to have was not going to be easy.  I discovered a plugin called Shape Bender.  It allowed me to take an object and bend along a curve.  This tool let me make more complex table legs.  So I quickly had a little table. 
   In my room I wanted to start with a table, lamp, and mirror.  The room itself would consist of a wood floor, wall papered walls, tin ceiling, a door and trim.  The room went together fairly quick. 
   Earlier in the day I decided to draw a parlor lamp.  I did this by downloading a picture of a lamp, and tracing it with arcs.  After the trace was complete, I spun the resulting shape to create the lamp.  The whole process only took minutes.  Why I made this lamp was so that I could work on getting a translucent glass surface that would project.  I did several experiments before I ended up with something that worked.  So I decided to put the parlor lamp in my little room.
   The rendering shows about 5 hours of time and 13 passes using Metropolis Light Transport rendering.  There are a good number of problems.  The light cast has a very strong pattern.  Diffusion caused by the glass should eliminate most of the pattern so only subtle patterns are cast.  The tube on the top of the lamp (originally the glass tube letting the candle smoke out) is black and doesn't look correct at all (although it is the only piece of glass correctly setup like real glass).  The mirror ended up reflecting a good deal of the wall and washing out the lamp reflection which I don't think would have happened.  And my parlor lamp was suppose to have a dim light to light the bottom of the lamp, but something in the drawing causes it to cast out a distinct band of light if I turn this light on.  All things to work on.
   I started work on a much better shade for my Tiffany lamp.  This one was to be more detailed and a little less ugly.  I have never tried designing any sort of stained glass work before, but I am a fan of works with a lot of geometric shapes.  So I tried something consisting of arcs and circles.  This time I started the design in one quarter of the circle and then copied it to the remaining 3 quarters.  After I had the design, I manually offset each void and removed the original lines.  Once I had a shade, I tried to turn it into a dome.  This proved to be almost impossible.  The problems I ran into on my last lamp shade were now amplified by the complexity of this new shape. 
   I decided to just make the design a flat stained glass work so I could color it.  I wondered if there was a way I could get a list of all the points in the drawing and make the curve myself.  For a while, this were looking really good.  When I export to Kerkythea the resulting file is XML, and all the points in the file.  I could write a program, or just copy the data into a spreadsheet.  There, it isn't a difficult manipulation to curve the flat surface.
   A 3d drawing can be divided into three parts: points, lines, and faces.  A point is a set of 3 coordinates in space (X, Y and Z).  A line is a connection between two or more points.  And a face is a set of lines that makes a closed surface or plane.  If my drawing were flat (i.e. 2d) one of the coordinates should always be 0.  Since I drew this from the top, the Z cord should be 0.  The value of Z should change if I curve the entire surface to a dome, but the X and Y values will remain the same.  The amount Z will change will depend on X and Y.  If you look at a dome from the top, it looks just like a circle.  The only things that changes is the depth.  This dept is determined by the location on the top—the X,Y cords.  So Z is a function of X, Y. 
   I was getting all excited about doing the curve myself, but there was one problem.  Sketchup can export to Kerkythe, but Sketchup can not import from it.  Long story short, there are no formats I can import/export that I can work with easily.  There is a Ruby plugin system, but it would not be quick to learn.
   Out of time, I decided just to work with the object I had.  The rendering today is a stained glass work. 
   The rending for today was an other 9 hours, but this time I have the glass materiel like I want it.  I also made the model more complex (and ugly).  A few people told me they liked my previous lamp shade better, but this one—despite it's looks—is closer to a true stained-glass Tiffany lamp.  The other lamp had large curved glass panels, which I have never seen in an actual antique Tiffany lamp.
   Getting Sketchup to make this model was no easy task.  Either Sketchup has some bugs when intersecting surfaces, or it has one really annoying "fetcher" when removing some faces from merged surfaces. 
   To make this lamp I started with a circle separated into 8 segments.  I drew a design in one segment—some simple arcs—and then offset them all to form 1/8th inch chambers.  To do this I used the offset tool and for each chamber offset it 1/16th of an inch.  I then removed all the original lines to leave the 1/8th inch chambers.  Once I had a full segment, I did a rotate and copy, flipped the copy and made a full quarter segment.  I then did a rotate, copy, and duplicate to complete the circle.
   Once I had the pattern, drew the dome again.  And once again the dome was 1/8th of an inch thick.  Then I extruded the pattern down through the dome, intersected the lines with the model, and then removed the extrusion.  What remained was my pattern projected onto the dome. 
   Now began a lot process of removed all the chambers between the cames. This did went quickly for most of the faces, but several faces were not separated despite the intersecting process.  It was a painful job of slowing tracking down what line was missing in order to separate the face from the rest of the surface.  In time however, I had the skeleton for the stained glass.  Then the process was much like before—draw a slightly smaller dome, move the skeleton onto the new dome, and intersect.  The result is that each of the chambers has a piece of stained glass that can be individually colored. 
   Next I quickly painted my stained glass, and I do mean quickly.  I grabbed a bunch of colors and just assigned them to areas—there was no artistic though what so ever.  Now I had the top to my Tiffany lamp.  The top looked really bad proportion wise, so I ended up stretching it vertically.  The same with the lamp base, which is the same base I had for my last rendering.
   After a lot of toying around, I finally got a stained glass materiel I liked.  I started with a glass materiel, removed the Fresnel setting, set the color, and added a strong bump-map texture for ripples.  This rendered just like what I expected out of stained glass.  The trick was the turning off the Fresnel setting.  Why?  Couldn't tell you, but it disabled the bump-map texture what gave the glass it's ripple.
   I also decided to add a mirror and four walls to my model chamber.  Makes it a little less boring, and I wanted a mirror.  So here is the night's rendering.  As you can see, the cames rendered almost white on the bottom side of the lamp.  They are also 1/4th of an inch thick because the glass has no thickness.  All items I plan on addressing.  I have already begun a better Tiffany lamp pattern to try tomorrow, so stay tuned...