ZBrushCentral

MRGBZGrab Problem

ZBrush Artworks
#1

I have this problem:

  1. Draw a 3D Sphere on canvas
  2. Select MRGBZGrabber, Auto Crop-> OFF, Shaded RBG-> OFF
  3. Grab Sphere with MRGBZGrabber (see fig. 01)
  4. The grabbed texture (fig. 02) and the grabbed alpha (fig. 03) is spheric, but the “Current Tool Preview” window show a different shape (fig. 04).

    To achieve a right shape (circle) you must grab the image with a precise square.

To do a precise square i use this method:

  1. Open PREFERENCES Palette, click on Utilities. The values within the red box are Mouse X and Mouse Y position (fig. 05).
  2. When click over canvas to start grabbing, note these two values (ex. 566, 599);
  3. To achieve a perfect square the final mouse position must be in a place where the two values differ the same quantities from the initial value.
    Example:
    X Start = 566
    Y Start = 599
    Difference = 33
    To achieve the square the following must be true:
    X Final - Y Final = 33

This method is difficult to do with a tablet !!

I hope the next version allow to do square area with MRGBZGrabber (Hitting Shift or Control).

If anyone known a more simple method, please post it.

cameyo

p.s. sorry for any errors and poor english.

#2

Try using the MRGBZ Grabber tool with “auto-crop” switched to “on”.

Another method follows:

I figured out a work-around, but it would involve having the full version rather than the demo version. I’m not sure which you have.

If you have the full version, what you can do is resize an empty document to a square shape of whatever size you need say 128x128 for example and then place on the canvas whatever you were going to use for the “alpha”.

Turn autocrop to “off” and then select the whole canvas with the MRBZ Grabber tool. That way, your alpha will remain perfectly square.

If anyone knows a better way, let me know as well.

You may want to put your request into the “Make A Wish” thread.

#3

Turning on autocrop should be all that’s necessary to solve the problem. It will automatically size the edges of the capture to the objects within the grab square. Since you’re drawing a sphere, you’ll get a square capture.

#4

Thank You my friends.

WingedOne: i have the full version of ZBrush. Your method don’t work if i want to capture only a part of the canvas (Sometimes my document are not empty).
“Make a Wish”: I have only a shot in that thread: i think to request more…

Aurick: Turn Autocrop On enlarge the texture and the alpha, but, more important, don’t work with multiple object.
See figure.

The problem is on “Current Tool Preview” window; if you select and draw with SimpleBrush you can see the difference: the shape is different from the grabbed image.

Have a nice ZDay

cameyo

#5

AutoCrop automatically crops the edges to the contents of the grabbed area. If there is nothing in part of the grabbed area, it will crop out the excess space.

As a result, AutoCrop will not always capture a perfect square. If you take a look at the alpha generated by your grab, you will see that it is slightly rectangular.

What happens to you in the preview window is that brushes are ALWAYS based off of square alphas. If you use a rectangular alpha, such as your capture, then ZBrush compresses it to make it square. This is what causes the distortion to the spheres.

However, it occurs to me that you can compensate for this if you wish. At the top of the Draw palette there are adjustments for the height and width of your brush. Use the formula in the attached diagram to make the brush shape match your grabbed shape.

#6

Go To your (Draw Pallete)ALT D will take you there and adjust the (WIDTH) when drawing with a simple brush.
and the setting you are using and by the look of your pic (fig. 1) your MRGBZ is not a perfect sqaure when grabing it which will make it oblong…
try make a sphere and when you grab it put your curser in the center of it to the corner outer edge in a perfect sqaure when grabing it so its not out of shape

#7

Thank You Aurick, i known this workaround (Modify Draw Height and Width).
Anyway, i wish have the possibility to do a perfect square from MRGBZGrabber itself. This will lend to create “Alpha-Brush” in a simple and fast way.

Thank You again

cameyo