Netherlands
Joined: Sep 26, 2009
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bug in transparent rendering?
Emmanuel,
Once again I was playing around trying out the near-impossible. This time it was an overhanging faceted roof. Imagine a room of 4x4 meters, on two sides the ceiling-roof overhangs one meter. The roof consists of several parts: - a top roof of 5x5 meters, made as a 5x5 room, floor not visible, copied with CopyAsNewFurniture and then inserted as a "normal" element. - a lower roof consisting of 3 "normal" roofs: one 4x4, and two roofs 4x1 meter, sloping upwards. Basically I get a room with a normal roof, on top of which sits a 2-dimensional sloping plane. Most walls have a transparent gif as texture, so they are (or should be) invisible.
Initially this rendered perfectly, but problems started soon after making a copy of the entire design with CopyAsNewFurniture. The copy rendered well several times, but after changing the light bulb inside, it started misbehaving, i.e. first it rendered only occasionally, a bit later it didn't render at all. Saving and reloading didn't remedy the problem. Looking at what render I now can make, even the original doesn't want to render anymore the way it should: the transparency is now completely lost. I attach the original file for you to inspect, in case I've made you curious.
Look at this house to see the source of my inspiration.
Hans
EDIT Further testing of the file seems to indicate that the copied and inserted roof is causing problems, similar to the problems with DAE files. It looks as if the orientation of the visible side initially was OK, but that later the visible side was at the underside, making the roof transparent. Even adding a texture to the roof part didn't make it visible anymore. Using Blackman-Harris, Catmull-Rom or Mitchell didn't bring back the roof. Neither could any of these restore the transparency, but that wasn't expected.
new website - under constuction hansdirkse.info
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last edit by hansmex at Dec 16, 2010, 1:54:12 PM]
Netherlands
Joined: Sep 26, 2009
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Re: bug in transparent rendering?
Emmanuel,
After another round of playing around with the hidden (or should I say "forbidden"?) fruits of transparency, I came across some more unexpected behaviour.
The idea was to explore the possibilities to make a roof, in this case the sloping side of a "standard" roof. I drew a triangle with walls at 60 degr angles, with two walls sloping at a 45 degr angle. I then inserted a room, made the floor invisible, and deleted the walls. CopyAsNewFurniture copied just the roof, which was then ex- and imported as an OBJ. So far pretty standard. The results are show below.
Clicking the name of the pictures gives access to a larger screenshot.
It may be worth noting that: - neither in Aerial View, nor in Virtual Visitor are the triangles visible in the 2D or in the 3D preview - if I apply colours to the triangles, they behave more normal, and are visible from one side only (as a roof is "supposed" to behave).
Netherlands
Joined: Sep 26, 2009
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Re: bug in transparent rendering?
Here's another example that illustrates that SH3D is not very consistent in the way textures are applied. Two opposing sides have the textures horizontal, the other two sides have a vertical texture.
The sloping faces that have a texture are ceilings, meaning that a house cannot have a roof with four correctly applied textures.
France
Joined: Nov 7, 2005
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Re: bug in transparent rendering?
Hans the triangle you imported doesn't probably have two faces. I tried your Transparent roofs file, and just had to go behind the triangles to view them. At the opposite, SunFlow renders all the faces of a model whether they are oriented towards the user or not. That's why you can see them at the two best quality levels and why there are problems with some DAE files too.
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Emmanuel Puybaret, Sweet Home 3D creator
