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Re: textures
From what I understand, the texture itself is transparent, or rather frosted transparent. I didn't make the texture file, so I'm not exactly sure. Let me paste...
newmtl glass Ns 96.078431 Ka 0.000000 0.302000 0.000000 Kd 0.671373 0.730980 0.749804 Ks 0.500000 0.500000 0.500000 Ni 1.000000 d 1.000000 illum 2
EDIT:
I had another AHA! moment. I forgot that the transparent materal still does have two sides. I was texturing the one side outermost and forgetting to texture the "underside" with the same texture. Even when the underside doesn't show normally, you still have to texture it or it will have what my friend told me was " x,y,z battles" I guess most rendering programs still have trouble with figuring the "dominant" side on a curved item when both sides are textured, especially with tranparencies. Or that is the information I recieved. Does this sound logical to you? (that is a general you for anyone who reads the thread)
No wonder some of the product design people I know feel such a sense of accomplishment when they are done with a model.. lol... there is alot to think about. Makes me wish I had gotten started on learning 3d sooner.
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last edit by whippetsleek at Aug 5, 2010, 5:15:00 PM]
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Re: textures
From what I can tell, I still have a lot to learn though! the settings you provided wouldn't work?? A d value of 1 = opaque, any setting less than 1 = transparent.
As Emmanuel mentioned and I mentioned.
Extra information for you: Frosted glass, Alpha blending or multiple layered textures aren't an option at the moment.
So if you are using .png or .gif files that contain transparent areas (meaning the image file also contains an Alpha blend channel) the transparent area will render as black in Sweet Home using Sunflow. The transparent textures shows in the 3D preview window because OpenGL supports displaying transparent textures.
For now we have to work within these limitations. One work around would be, produce your model in Sweet Home, export it as an .obj, import into another application like Blender, add extra textures and lights and render.
Wow my 35 + light 12MP render just finished, took just over 37 hours, it is a massive file though, many of the lights in one large room and are placed within spotlights, each of the spotlight have back and side grills, so the lights are also shining out of the small holes too, producing lots more small light paths to calculate.
Here are the results of the settings you provide above. The left vase is the settings you gave, the weirdness next to it is the settings you gave with a d value less than 1.
The Ni value is the diffraction index. Ni 1 means that light doesn't bend while traveling through an object, which as can be seen produces strange results.
The vase in the middle has a negative Ni value, producing a kind of concave effect, then higher Ni values on the right.
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Re: textures
Yes, that was exactly what was happening with my models. I'm guessing the oddness comes from trying to make a frosted glass? Your middle vase I think is the closest to what I was trying to achieve. You least got most of your model to show, mine was all black.. I guess because of the specific jpg I used? I almost always use Jpgs because they are easier to change IMO then gifs, I use gif almost exclusively for animations.
Just an off the wall question, but if the renderers used algorithms, I assume, to make their calculations for light shadows and such, why don't people use vector graphics instead? Wouldn't a vector graphic be much easier to formulate inside of a model?
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Re: textures
Personally I wouldn't use gif files for textures, I was just mentioning a couple of file types that support Alpha blending. gif files have too many bit depth limitations for good quality images. I always use jpg or png.
If it is helpful, the vases in the test render don't contain any texture mapped images, just the file attributes you mentioned, with a few tweaks.
I have tried all sorts of ways to produce frosted glass for another user and also a render I was working on, without success, please let me know if you find away, within the current Sunflow limitations.
As for vector graphics idea. Models are produced by vector graphics, mathematical calculations between points, so I'm not sure what you mean?? or do you mean for textures?
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Re: textures
Yes, for the textures. Say you have a photo of a flower, and you want just the "fractual" shape of the flower to be applied to the surface of a face. The outer limit of the flower is the border of the texture. With jpg, you have to use the actual graphic of the flower, and then put some kind of border to make the texture into a polygonal shape, like a square or rectangle.You can't have just the flower unless you line up the edges to make a seemless graphic.
In vector graphics, the egde is the end... not like rasters which make invisible the squared edges. Say the frosted glass was made with vector curves as the texture. You could alternate the vector curves in a very small scale between opaque and transparent and in large scale, it should look frosted. Because the texture has it own curve, and the curvature of the face it is applied to, the light should bend in 4d basically.
I hope I explained that clearly.... I know what I am thinking in my head, and don't know if I can explain it correctly.
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Re: textures
Ah yes I understand what you mean although I'm not sure it would bend time (4d) well apart from the long render time required.
I already tried making a highly subdivided Spline mesh, with alternating faces removed, reduced in size, then cloned and joined several times. it creates quite a large and slow to render model because so many calculations are required. A bit like the holes in my lamps, where many extra light path calculations are required. So I would imagine that is why they use bitmaps to help simplify and reduce the number crunching process.
With bitmaps only using one poly or two triangles for a flat surface it keeps things very simple.
Ideally vectors would be better so they were resolution independent, plus the model file sizes would be smaller, but I guess at the moment it would add to much extra processing?
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Re: textures
lol I was thinking of bending the space time... hmm, when a light ray bends, it travels along with it time along the path of say a prism. An object with a mass or a "solid" object let's say, travels at the same ratio of distance/ time no matter what distance it is traveling. Say you throw a snow ball, that snowball will hit the ground at the same time as another same size and weight ball is just dropped from the same height. Light works a little differently, and always travels a longer time along a path. Which is how you get the effect in real life from frosted or etched glass. The light bends and takes longer to finish it's travel, being refracted at different intervels. But anyway, you are probably right that the calculations would be extreme and resource heavy. Too bad you can't just make a fresh calculation after the light has passed through the object, to get the frosted effect.
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the settings you provided wouldn't work?? A d value of 1 = opaque, any setting less than 1 = transparent.
