exr manipulation

[jpaul]

Hello, i downloaded a PBR from the internet. but i want to change the color. in the description of the product it's said it can be done by adding a mask in the composite layers. idk how to do this, and i can rely on GIMP only, as i don't own photoshop. and paint.net doesn't do the trick. so is it possible to do this in GIMP, if yes how? here's the exact descriiption of the pbr so you have a better idea

Material of old painted boards. The color is green by default, it can be changed in Composite Layers using a mask (disabled by default and also not available in FBX)

Thank you

[sallyanne]

You need a suitable software like BI/Suite Hypercube to open a PBR file. Without proper software you will receive a Windows message "How do you want to open this file?" or "Windows cannot open this file" or a similar Mac/iPhone/Android alert. If you cannot open your PBR file correctly, try to right-click or long-press the file. Then click "Open with" and choose an application. You can also display a PBR file directly in the browser. Just drag the file onto this browser window and drop it. https://filext.com/file-extension/PBR#:~...0drop%20it.

While GIMP is not officially a PBR authoring tool, the changes to Alpha Blending (changing into Linear space from sRGB) in Second Life will make textures created in GIMP display their alphas correctly (GIMP defaults to linear alpha calculation) https://wiki.secondlife.com/wiki/PBR_Materials

[rich2005]

That looks very like ChatGPT to me. Please only post what you know and have user experience.

Gimp 2.10 can of course open a .exr image I have a sample file but nothing for Physical Based Rendering (PBR)

Regardless of ChatGPT, Gimp is probably not the tool for this.

[jpaul]

i don't even know what chatgtp is. i know it has to do with AI but that's all. here's the link to the product. as you can see on the descriptive images there are several colors shown. but when you download the thing there's only green. i want to create several variations yellow, blue.. but idk what the author means by adding a mask to the composite layers

https://www.turbosquid.com/3d-models/3d-...al-1908980

[sallyanne]

But you mentioned 3 types of files. Which one are you having problems with?
You are correct Rich, I do not have the expertise which is why I provided links

[rich2005]

@jpaul

This is not a job for Gimp. It says on the website as you referenced in your first post.

Material of old painted boards. The color is green by default, it can be changed in Composite Layers using a mask (disabled by default and also not available in FBX).

Remember Gimp is 2D editing, if the image is a bitmap and on the long-shot you can open your file in Gimp, you can change the colour in several ways but probably no use to you.

Bottom line, can you open the file ?

[jpaul]

no i mentioned only one file the exr. i was talking of the variations i'd like to achieve

yes i could open the exr in GIMP, but once opened idk what to do with it

this is driving me nut why painted wood pbr are so hard to find. they're rarer than gold

i can eventually send the exr to one of you if you'd like to give it a try. but i can't post it here for obvious reasons

[rich2005]

There are texture and pattern sites around (not as many as there used to be) example this one https://www.textures4photoshop.com/tex/s...ood+planks  The images are not going to be as high quality .exr files but you can up the quality setting in Gimp Image -> Precision

You can change the overall colour in different ways, Colors -> Colorize or Colors -> Map -> Color Rotate or by adding a color-filled layer on top and changing the layer mode. This some stripes of different colors.

   

but nothing to do with composite layers using a mask and a PBR file still no use with GIMP.

[jpaul]

just to be sure. i don't want to change the color of the whole image, but only the painted parts. changing the color of a texture is extremelly easy to do in Unreal engine, which i'm working with. but it'll colorize all the texture. this is not what i want. i want the texture parts where the paint has decayed to stay eutral/untouched. this is where the whole thing is. thanks however to all the efforts put in trying to help me. i've contacted the author at turbosquid via the support, and asked him/her how he/she achieve the thing. they transmitted my request. we'll see the answer. or maybe i should make the mask myself by hand. sounds trick, but not impossible. we'll see.. i'll tell you

[rich2005]

Quote:..just to be sure. i don't want to change the color of the whole image, but only the painted parts...snip

Yes, looking increasingly complicated to give an answer without a good example image, however

You can add a coloured layer on top and create a layer mask from a selection Layer -> Mask -> Add layer Mask then From selection. The advantage is, if you save as a Gimp .xcf, you can change the colour and the mask at a later date. Maybe this is where the composite layers and mask comes in.

Alternatives, same selection and the Hue-Chroma filter.