As the title states, I want to create an image that blends with other images. Does anyone know how to do this?

You can blend textures in a shader without using alpha layers (like for water, skies, etc) using blendFunc in the shader. But if you specifically want to use an alpha (for different levels of opacity across the texture) then what image editor are you using?

You could try photoshop.

I'm using Photoshop, but I have little knowledge of how to use it properly.

I'm a Paint Shop Pro type of guy, so for you I'll say YouTube is your friend...

www.youtube.com/watch

^^^ That is in CS5 but it's still pretty similar for older versions of PSP.
So when you have your TGA image sorted out with an alpha, then you'll want to write a shader for it using alphaFunc stage directives:

q3map2.robotrenega...directives.html

A good example is textures/base_floor/techfloor2 in base_floor.shader.

Thank you for that, it works!

I prefer GIMP than a PS... It's not good as PS, but it's free and have full support on Linux... I'm using GIMP 2.8.0, which is a bit improved version of GIMP - have function of one-window mode - it simply docks the additional windowsto the workspace window and you can maximize the window, so you haven't to move the tools or layers window to the other side, when you want to run something else (for example Quake3)... All images opened are in single window, you just have to switch the tab with image preview to the tab with preview of image, you want to edit now... All changes you do in these images are done in one window, the tools, layers and brush presets are docked on the sides of the window... No moving needed...

Also have improved image saving - function Save (as) can save only native gimp format XCF, for the saving in other formats use function Export (to)... However exporting isn't fully done yet, for example you cannot make animated GIF, because of lackess of the GIF options (including animation options).

Blending image you can make with Layer mask in GIMP. Select the mask (don't use it!), export ot TGA and open up...

I'm enjoying this :D
i270.photobucket.c.../alphablend.png

@Euronymous: What Map editor are you using? Is it easy to use?

Looks like a Radiant, and a copy of Q3ASE above it to edit the shaders with.

As leilei said, GtkRadiant 1.6 and Q3ASE. I know Q3ASE may seem noobish, but I find I get work done faster using it.

@Euronymous: Could you give me the link to Q3ASE? If I am to create a map for Quake 3, I need something that is idiotproof for me.

I was unsucessful in my first attempts to create a map because I had no f*cking clue as to how to create a skybox. It was over my head.

I'm using the Q3ASE to make the shaders, too. It's easy and you can test the shader, how it works before you save it (however, it has its own render engine, that is slightly a bit different from Q3's GL renderer, so it's important to test it also in Q3... The difference isn't too much visible, so there's more the same than different...

After the shader file creation with Q3ASE I'll always edit the shader for some unexpected issues (like wrong shader name), also have to optimize the code (decimal number don't need the zero before dot, Q3ASE always adds it - think about potential issue)...

Sure: www.bpeers.com/software/q3ase/

@CZghost Yeah, they need an update to remove that.
Edited 1.32 minutes after the original posting.