Textures: Before & after

[FlyingWren]

Hi,

We have a graphic of just plain RGB gray (127, 127, 127) applied to a model in our world. When I take a screenshot of that model in our world and look at it in a paint program, it shows up as RGB (129, 128, 129).

I know that in current Vizard releases, pixel color comes from a combination of three factors (texture color, underlying object color, and lighting color). Does it add these with equal weight? What's the quickest way of achieving WYSIWYG in textures?

[farshizzo]

Hi,

If you want the texture to show up exactly as you see it you need to apply it in GL_DECAL mode and disable GL_LIGHTING on it. Vizard does this automatically on textures and the difference you see is very small. This leads me to believe that your montior color depth is set to 16-bits. Try changing it to 32-bits. Let me know if this works.

[FlyingWren]

Hmm-- just checked and my monitor is in 32-bit color after all.

Any other ideas?

[farshizzo]

Are you using the viz.screencapture() function or are you just using the Print Screen button? If you are using the viz.screencapture() then it is probably due to the fact that it saves it as a jpeg. If this is the case, then use the Print Screen button.

[FlyingWren]

...if it helps you debug:

the end-result RGB always ends up higher than the original texture RGB (and the RGB values become nonequal from each other, ie, it's not a true gray anymore).

The actual RGB value can differ depending on where I take the screenshot (ie slight differences when I move the viewport)

[FlyingWren]

Tried both printscreen button and viz.screenshot() -- it happens in both :/

[farshizzo]

Hi,

the end-result RGB always ends up higher than the original texture RGB (and the RGB values become nonequal from each other, ie, it's not a true gray anymore).
The same thing happened to me when I was in 16-bit mode, when you zoom in on the ball the pixels are dithered. But when I changed to 32-bit mode it was a solid gray color. If this isn't working for you then I'm not sure what is going on. You may have to reset your computer after changing the color depth. Also, after you hit the print screen button, which program are you pasting the screenshot into?

[FlyingWren]

Was pasting the screenshots into Paint Shop Pro (a Photoshop clone) at various levels of zoom on the texture in question. Also, I realize that in using viz.screenshot(), certain areas of the image may be RGB-distorted due to the fact that JPEGs are a lossy format. That doesn't seem to be the issue, though.

Well, having tried this on another computer, the RGB values look fine. Neither computer has any external gamma correction or any such thing applied; the only differences that jump out to me is that the computer that worked had Vizard 1.098 and a Quadro2 video card; the one that doesn't has Vizard 1.097 and a Matrox G400.

I only care that the RGBs look fine on our rendering computer-- assume this is the case, unless you hear otherwise :)

Again, thanks for your help.

[farshizzo]

There was no major difference between 1.097 and 1.098, so I'm thinking the problem was with the Matrox card. But just to be sure, would you mind upgrading the computer with the Matrox card to 1.098 and see if it works then? Thanks a lot.

[FlyingWren]

I'm in the middle of taking some time off, but will happy to try that when I return.

[FlyingWren]

Just checked on this -- Vizard 1.098 performs like exactly like 1.097 in terms of the graphical output, as far as I can tell.