Fixed guidelines when rotating image

[zio3d]

Hello everyone,

I'm using GIMP on Windows and was wondering if there was a way to keep the guidelines fixed during the image rotation stage.
I have noticed that when I rotate an image, the guidelines move with the image and do not stay fixed.
Does anyone know if there is a solution to this problem or if a request has been made to implement this feature?
I also tried to make a new layer with lines on a transparent background but the lines of the layer disappear while rotating the other layer.
I needed it to better rotate the image in order to make an object completely horizontal (or vertical).

I currently use Gimp 2.10.32 on Windows 10 64 bit.

Thanks in advance for the help.
Davide

[rich2005]

Quote:I'm using GIMP on Windows and was wondering if there was a way to keep the guidelines fixed during the image rotation stage.
I have noticed that when I rotate an image, the guidelines move with the image and do not stay fixed.

Correct. You are rotating the view, not the image. No pixels are translated (moved) in the image. Export the view and it is the orientation or the original.

Quote:I also tried to make a new layer with lines on a transparent background but the lines of the layer disappear while rotating the other layer.

You can do this using paths. Draw the path(s) in make the path(s) visible and rotate the canvas, This time the image pixels are moved and you will get parts of the image cropped off.

Quote:I needed it to better rotate the image in order to make an object completely horizontal (or vertical).

For straightening an image, all you need to do is use the measure tool. Draw a line along the horizontal or vertical then apply straighten. The Gimp docs: https://docs.gimp.org/2.10/en/gimp-tool-measure.html or my 15 second animation   https://i.imgur.com/opPTntl.mp4

[Ofnuts]

(05-30-2023, 01:10 PM)zio3d Wrote: Hello everyone,

I'm using GIMP on Windows and was wondering if there was a way to keep the guidelines fixed during the image rotation stage.
I have noticed that when I rotate an image, the guidelines move with the image and do not stay fixed.
Does anyone know if there is a solution to this problem or if a request has been made to implement this feature?
I also tried to make a new layer with lines on a transparent background but the lines of the layer disappear while rotating the other layer.
I needed it to better rotate the image in order to make an object completely horizontal (or vertical).

I currently use Gimp 2.10.32 on Windows 10 64 bit.

Thanks in advance for the help.
Davide

It depends on the "directtion" of the Tool. Many transform tools have a "corrective" direction, in which you move the guides over the image, to show what should be straight/upright, and the image is straightened at the end. In direct mode, you move the image directly. 

Also, when you use these tools you can use the preview and the "composited preview" combines what you transforms with the existing image.

   

[zio3d]

Thanks rich2005 for your info. I had previously used the "measure tool" command but never noticed the "Straighten" button. Very useful video .
Same thing for the path(s), I hardly knew them and I never investigated them. So you gave me the chance.

Thanks also to Ofnuts, I've always used rotation in normal mode and never corrective, I didn't even know it was there. It turns out very useful .