Useless VGA

[Srek]

Only specific renderers like Gelato use the GPU. In general no standard renderer supports them. By far the most 3D apps only use the graphicscard for editordisplay, not final rendering.
The main reasons beeing lower FPU precision, bus bandwidth and RAM size.

Cheers
Björn

[A-Boy-From-Heaven]

Thansk a lot for reply. But I have sent this question to a persian site forum and got a reply and two image attachments showing a huge difference in final output when rendernig two identical scene with different VGAs.

[Szos]

...got a reply and two image attachments showing a huge difference in final output when rendernig two identical scene with different VGAs.
No dice. You will get 2 different output images if you render using 2 different renderers (like say, scanline versus v-ray versus brazil), but if using the same renderer you could render on a render-farm node with no graphics card and still get the same results. Also, I do recall seeing some posts a ways back of people rendering on different CPUs (like AMD versus Intel) and I was shocked to see ever so slight changes in final output.

Please post up the images that you saw in that other forum and if you coudl translate wha tthey wrote - would be curious to see where the confusion is coming from.

[MrJonathan]

Only reason there would be any difference in a software render would be if the scene is using procedural textures, and the various PCs in the render farm utilize different CPUs or CPU architechtures, which can sometimes lead to a few differences in the look of the texture.

And as others have already mentioned, rendering on the GPU is only done with real-time stuff (i.e-the viewport, 3d games, etc.). There are some programs that render, or partially render that is, on the GPU however they haven't really caught on for whatever reason(s).

[lots]

Thansk a lot for reply. But I have sent this question to a persian site forum and got a reply and two image attachments showing a huge difference in final output when rendernig two identical scene with different VGAs.
The GPU plays no role in the final render of most applications out there. Like Srek says, only a hand full of GPU renderers exist (such as Gelato) Most 3D apps do not utilize the GPU for rendering. In fact the GPU's only purpose is to draw triangles in the view ports, it doesnt even compute mesh deformations or edits.

Perhaps you did not get the whole picture from your post in that persian forum :)

EDIT: Thanks Szos :)

[Szos]

The CPU plays no role in the final render of most applications out there. Like Srek says, only a hand full of GPU renderers exist (such as Gelato) Most 3D apps do not utilize the GPU for rendering. In fact the GPU's only purpose is to draw triangles in the view ports, it doesnt even compute mesh deformations or edits.

Perhaps you did not get the whole picture from your post in that persian forum :)

I am sure you meant to write "GPU" in that sentence. :D

[UrbanFuturistic]

Only reason there would be any difference in a software render would be if the scene is using procedural textures, and the various PCs in the render farm utilize different CPUs or CPU architectures, which can sometimes lead to a few differences in the CPU architecture.The main one affecting that would be the algorithm used (internally on the processor) for the pseudo-random number generator which is a notable difference between AMD and Intel chips, never mind between architectures like x86, PPC or MIPS. This wouldn't affect true randomisation methods, like Monte-Carlo, but it's the only one suitable for texture consistency... although it's another reason to not use procedurals for the final render, baking them into a texture map before distributing on a render farm may use more disk space and bandwidth but it's consistent.

Other than that I shouldn't think there are many (if any) other instructions which could be done in a way which affected the result.

[A-Boy-From-Heaven]

Here are the Images

[mummey]

Here are the Images

Those are color issues. One (or both) displays are not calibrated correctly so the color appears different.

Nothing to do with CPU or GPU.

[lots]

The two scenes can be drastically different _IF_ the GPUs that were used were some how drastically different and you are using a GPU based renderer such as Gelato. Another problem may be drivers on the specific card, renderer is different, etc.

Like I said in an earlier post, we do not have enough information to go with these pictures. What renderer was used? what are the computer specs? what 3D app? Are these renders screen shots? Are they pictures of the screen? What are the driver versions?

What's going on in these two different renders of an identical scene?

From my POV it looks like someone photoshopped the second image and took out some color :P

In a normal renderer such as MR or VRay, the GPU will have zero effect on the final output of a render. Don't believe me? Look at all those benchmark sites out there. There are thousands of different configurations, yet the renders are, for the most part, identical. Sure a procedural texture here and there may differ due to processor used, but the overall image should not be as drastically different as you see here.

[lots]

Those are color issues. One (or both) displays are not calibrated correctly so the color appears different.

Nothing to do with CPU or GPU.
That is probably not it either :) If a display is not callibrated correctly, it should not affect the outcome of the image unless some post work was done on each display.

[Szos]

Just for shits and giggles, I loaded up both images into PS and if you boost the saturation by about 72% percent, it will look essentially exactly like the other one. Somethign is wacked with the gamma or other color-correction settings.

[A-Boy-From-Heaven]

Oh, strange, so I need to ask the owner of the images wheter they are really identical or not.
Anyhow I will let you know. Thanks for your replies

[A-Boy-From-Heaven]

I am now sure that scenes are excactly the same but as Szos said there must be somthing wrong with color correction setting of two scenes.

[brianod]

Gelatto is one GPU based renderer. Another one is RTSquare. They have a free Maya download to test it out. It's pretty cool and I guarantee your graphic card temperature will go up when you use this renderer.

http://www.rtsquare.eu/

[davijin]

theres gpu based renderers out there ie gelato. but they arent that great imo, you can do more with mental ray, vray and some of the other renderers out.

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