terrain blending tutorial

(phobos) #21

Hrm… learning… how novel!

* Nominates this thread for sticky *

(ratty redemption) #22

@phobos, thanx man! :smiley:

and if ydnar does so, could we also sticky the water blending tut that NOP and I posted a while back, I`ll be updating that soon as well as continuing the terrain one.

(dime1622) #23

yeah, that pic of my alpha channel is a screenshot, its actually 512x512. it looks like this now:

that last pic i posted had rgbgen of 0.6 0.0 0.0. it’s there, but not a whole lot is happening.

ratty, id love to get this tutorial out (crediting you, ydnar, and rgoer of course) because it will really help me and a lot of other people. maybe my brushwork is wrong. would you mind sending me your map, shaders, and textures you used for this?

(ratty redemption) #24

@dime, your image link appears broken, and I guess your using different desktop gamma to me then?

ratty, id love to get this tutorial out (crediting you, ydnar, and rgoer of course) because it will really help me and a lot of other people. maybe my brushwork is wrong. would you mind sending me your map, shaders, and textures you used for this?

well seven_dc has already posted a shorter noob tutorial based on mine, so you might want to chat to him about how much you guys convert the advanced tuts into noob ones… I think it would be great if at least one of you is doing this as I update mine over time.

and if it would help I can ul a sample pk3 with my brushwork, shaders, editor images and games tex, but since Im modifying rtcw tex, to make the alpha channels, I think each game should have its own made so we don`t infringe any copyright… perhaps I should just include my alpha channels, rather then the original game tex, what do you guys think?

(dime1622) #25

yeah, i saw that after i posted. it works now :smiley:

(ratty redemption) #26

cool and how did you get it working? :slight_smile:

(dime1622) #27

i got rid of the dithering and just went to blendFunc, like sevenDC’s stuff. with some tweaking of his shaders (stuff wasnt lining up right) i got this:

i had to turn the dirt’s alpha channel to 100% white, or else you could see through the terrain lol

(dime1622) #28

i made a tut, its posted here. if you think its a good idea, ill post it on this forum, since i went literally step by step. for complete morons like ME :smiley:

(ratty redemption) #29

@dime, cool and you can always try the dithered blend later on :slight_smile:

I`m still reading through your tut, but I noticed the errors in common_alphascale.shader

the q3map_alphamod scale value of each shader should exactly match the name of the shader.

edit: since your dimedirt.tga is a “base tex” you don`t need an alpha channel, and a pure white one will totally mask, ie not blend, any parts of previous stages, so you can safely remove, that alpha channel and the blendfunc shader line from your first stage of your dimedirt shader.

speaking of which, I would replace the pic of the shader on your site with text, because some people will want to copy n paste lines from your tutorial, and they can`t do that from a pic.

(dime1622) #30

ah, kewl. i thought i had fixed the common_alphascale shader. whoops! its fixed now. i guess i must have not changed it when i re-downloaded the shader.

(ratty redemption) #31

np, and are you func_grouping your blend shader brushes with the volume ones?

(ratty redemption) #32

although dimes tut does work and will be fine once its finished, the principle is slightly different so before any one starts working from it, just give dime and me a little time to debug his and so I can explain what I think is happening.

(ratty redemption) #33

now create a set of trisouped brushes. i will do a road. i textured the road with textures/temperate_sd/dirt3 because my textures/dimesblend/dimedirt.tga is just a copy of it. the grass around it is textures/dimesblend/dimegrass.

eh, it looks like you haven`t painted any of your trisouped brushes with your dimesdirt shader, is that correct?

also, there is some bold typeface errors you might want to fix.

I`m not trying to score points here, just trying to help you make your tut as clear and accurate as possible.

the trisouping is fine, so is not using a decal, polygonoffset blend like I use in my tut, ie I think your using a multistage shader and blending the top layer onto the base tex, so I would change your dimesdirt shader to look like this.

textures/dimesblend/dimedirt
{
	qer_editorimage textures/dimesblend/dimedirt.tga
	q3map_forcemeta
	q3map_nonplanar
	q3map_shadeangle 179
	surfaceparm grasssteps
	{
		map textures/dimesblend/dimedirt.tga // base tex stage
		rgbgen identity
	}
	{
		map textures/dimesblend/dimegrass.tga // blend stage
		rgbgen identity
		alphagen vertex
		blendfunc blend // only the shader stages using blendfunc or alphafunc will be affected by the volume brushes.
	}
	{
		map $lightmap // lightmap stage
		rgbgen identity
		blendfunc filter
	}
}

then paint the dirt looking brushes in your example with this new dimedirt shader and that should work fine.

how I think this would work, would be on the outside of the road is a plain non alpha blended grass shader, and covering the whole road area is a dirt layer, but this is blended “underneath” the grass layer.

which from left to right fades from 100% to 0% on the inner border where the first volume brushes are, then as the next border is also at 0% the grass is still invisible until it starts to fade from the right of the volume brush to the edge of the blend shader, which is another plain grass shader.

(dime1622) #34

i know youre just trying to help out ;), i actually really appreciate it. i did not use func_grouping, as i found that it didn’t make a difference.

i did, however, paint the brushes between the grass and the volume brushes with the dimedirt shader.

(ratty redemption) #35

i know your just trying to help out , i actually really appreciate it. i did not use func_grouping, as i found that it didn’t make a difference.

cool and I think the reason the func groups would be redundant in your example, is because your volume brushes arent enclosing any verts from other brushes that you dont want blended.

in my example, I have cloned brushes using a decal blend sharing the same verts as underlying brush that I dont want affected... if those underlying brushes didnt use shaders with blendfuncs or alphafuncs, then I wouldn`t need to group the blend brushes either.

in my next part of the tutorial, it will be more important to group them as my volume brushes are sharing verts with dotproduct shaded brushes and I don`t want them blended.

we should point out, there is no exact right or wrong way of using these types of blending.

it`s more a matter of choosing which method is best suited to get the desired results, eg dithered or linear fading, decal or multi stage shaders.

and if we are concerned with optimizing our maps so the fps are as high as possible… but even that is a grey area, as some mappers will be able to use extensive blending in small vis areas that don`t appear to have any impact on fps, but in large open maps it would accumulate and eventually become more noticeable.

(dime1622) #36

i disagree. my first way sucked haha, dont know how i messed it up, but i suggest not doing what i did :drink:

(ratty redemption) #37

@dime, I hope I didn`t put you off?

other then a few tweaks being needed, I still think you gave a good example of how alpha blending can be used.

(dime1622) #38

haha, not at all, i was saying my first time at trying the dithering was less than desirable lol. i really appreciate the help youre giving, helps me improve my method :wink:

(ratty redemption) #39

ah, cool, so your still be publishing your tut on your site? :slight_smile:

maybe you could link to your site from seven_dcs topic if you havent done already?

certainly anyone reading mine will see your link, but it might get confusing with we start 3 topics in ydnar`s forum on terrain blending?

anyway, its up to you guys what we do with all this... Im very happy I`ve helped inspire other mappers to use the new blending, and I look forward to seeing more maps using them in various ways, which no doubt will inspire me as well :slight_smile:

(dime1622) #40

right, yeah, it may get confusing. i mainly wrote that tut for my mappers, but posted it on our forums for anybody else who was curious. however, it is very very close to seven’s tut, and both achieve the same effect