Please forgive me, I′m a simple scripter with no education in this. I just tonight downloaded Gimp, and now I can make and export blood stains - I′m happy!

But I know from experience - and now REALLY from experience - that something needs to be done some way if the textures are to be used in particle effects. So give me a hint, I just tried a few things but my intuition seems to fail me, my particles are flat squares with a purple background. :blush:


EDIT: I realized this should have been posted in the "Quick questions" thread. Sorry guys, I just didn′t notice it in time...

Purple usually indicates that the texture can not be found -> re-check the paths and make sure they are relative to the data folder.

Ah, no this is not the case, sorry I should have made this clear.


The problem is that instead of 3D/roundish looking particles I get 2D PLATES. It′s like flipping a deck of cards in the air. The blood pattern is there, as a 2D photo in the "cards", for some reason the whole square is tinted light red, like as if some lighting thing altough there should be no background.


This is probably completely off, but my guts say the problem is that Oblivion treats my particle texture as a surface texture, the purple relates to missing normal map, which is not required with particle textures, which kinda proves my texture is missing some property to make it "particle texture that looks 3D not 2D and doesn′t require a normal map and doesn′t display the background of the texture".



In short, the same effect happens if you haphazardly pick a texture, and put it in a shader. Squares. You can′t use any normal surface texture in a shader, this I know - but I just can′t figure out what′s the key difference with those that are intended for particles and do work.

IF the texture is showing up and you are still getting squares it sounds like an alpha channel problem with the texture -- Have you opened and resaved the texture at some point (and saved in DXT1 instead of DXT3 or DDXT5 so that the alpha info was deleted ??) - Or it might also be that the Nif is lacking the NiAlphaProperty node on the NiParticleSystem block


The main difference is that most reqular textures (those with no transparency are save as DXT1 so that the filesize is smaller since it does not save the alpha channel) where textures with transparency are saved with at least a 2 bit and usually full 8 bit alpha channel for the transparency (2 bit provides simple transparent or not while 8 bit provides grey shades for partial to full transparency !)

That's right. Particles are really mini-billboards, as that's the computationally cheapest way to do it. Since you have a lot of instances of the particle, rendering each one has to be as simple as possible.

Most fires are billboards with an animated texture, instead of particle effects for the main flame, and particles just used for sparks etc around it. Depending on what you're doing with particles, you may need to consider the same trade-offs.

This is exactly what a Particle is a Square Plane Billboard -> how you see 3D visuals is a trick of Emission Depth and Facing Angle nothing more.

To get "Round Looking" requires a properly set up texture that only has the center-ish area colored the outter areas need to be lacking coloration not just colored but erased becasue the colors still exist they are just full transparent and this tends to cause Alpha issues on Systems that use SRC Alpha to Inv SRC Alpha.



This problem is most likely what was already mentioned being an Alpha issue either in your system not having the Property or the Texture not having it.

This. This is what I was after. Thank you! :foodndrink:

From what I understand, my problem is that while I did set the background transparent, the game still adds some coloration to it - making the whole square visible and breaking the illusion of 3D. This also explains why there′s that bland light red color that′s not added to the texture anywhere - it′s "added" by the engine.

I′ll start fighting with this right now, but if someone can point out how to totally "remove" the background in Gimp please give me a hint, I′m really so new with this program and all the concepts.

If you send me the files and textures I can take a peek at them and fix any issues then you can check the difference to see what was off.

I think I figured out my problem, to an extent. If I simply open up a new "plain", and paint something on it, it comes out right. The reason I was having trouble, was some step involved in this tutorial that I accidentally bumped into and which made me want to try.

http://www.gimpusers.com/tutorials/blood-splatter-texture.html


I′m pretty confident I′ll work out how to create things like in the tutorial without messing up the texture for particles, now that I have one case of working and one case of none-working steps, but if you can spot the culprit just like that I′ll apprecite it a lot naturally.

In any case, thanks a lot for all the help, your posts were exactly what I needed already. :foodndrink:



EDIT: It seems found the trick between using the technique in that tutorial and displaying the results in particles.

After I′m done with the tutorial, I need to add an alpha filter and apply it, only then save as dds. My vocabulary on the subject fails here, but that seems to extract only the desired part of the texture instead of the whole square, so to speak.


EDIT2: Wait a second...no I don′t have to do that. I wonder why all I got was a read square - already in Gimp - when trying to do this the easy way. It seems I don′t have to do anything specific at all, suddenly, and everything works just fine. Weird.


EDIT3: ..but then again, in closer looking my particles are just fully saturated figures of the splatter I paint. I got rid of the background, yet the texture is missing all shades that would bring it its depth.


EDIT4: Ok realised that it′s not a good idea to try and make particle textures using a STAIN tutorial. No wonder the result is flat looking. I have pretty good results now, actually to a point I think I′ll end up using this texture.

Thanks for all the tips Saiden, thinking about everything you said here helped at lot in finding my own tricks in making it look right. :goodjob: