Blender: Tips, Tricks and Techniques

– [David] In this week’s Blender’s Tips, Tricks, and Techniques, we’re going to create fire. Out of a node! We’re actually just going to use all cycles nodes to create fire, it’s going to be awesome. Now this tutorial was inspired by my dear friend Derek Parker, also known as LORD ODIN on the Blender world of artists. He taught use this really cool technique, so thank you, LORD ODIN. So let’s get started. Now, to create this, we’re going to need to switch to cycles, and we’re going to want to delete this.

Shift-A, Plane, let’s add a plane, scale it up our Y, or X, doesn’t matter. I’m going to say X, 90. Now let’s come over here, let’s go to Node, hit T to close it off, N to close this off. New Material, I’m going to zoom in here, now things are going to get really, really complicated, so let’s just start all the way from the left. We’re going to need our texture coordinates.

Next, we’re going to need a mapping node, we’re actually going to need two of them. So let’s go ahead and add one, and Shift-D, B to make a box, G to move ’em over. Let’s go ahead and make a math, and then we’re going to need a vector math. So add vector math here, we’ll keep this over here for now. Let’s go ahead and add noise. Trust me, this is going to get really complex, but we’re going to do it together.

Combine XYZ is the next node that we’re going to need. Let’s get a little bit more real estate here, here we go. Scooch this over here, actually right here is where I want it. Shift-A, gradient right there. Now, we’re going to want a color ramp. Let’s come over here and move these over. Now this math node, we’re going to switch it to a multiply.

If you can’t see that, I can zoom in here. Multiply, and let’s click on it and move it right here. Let’s add another color ramp to the top here. We’re almost done. We’re going to add a transparent. We’re going to add emission, that’s going to generate the actual light, while transparency will generate the actual transparency of all of it when I mix it together with a mix shader.

So now if you’re just as confused as I was, don’t worry, I’ve got you covered. First, the texture coordinate’s going to specify the UVs. In this case, we’re not going to create any, we’re just going to generate it on the fly. So let’s just go ahead and use the object, and plug those two in here. Now, this first one up here, this mapping node, this is going to control a lot of the look of the fire, so let’s go ahead and change these scales so I can adjust a few things.

Don’t worry, we’ll take a look at why later. Down at this mapping node, this is actually going to control the licking of the fire. We’ll leave it alone for now and just connect it to the noise texture. And then connect its factor to X. Now, under noise here, you can switch this to say detail 16, 15, anything higher than say, five, or 10, that way you have a lot of detail in that noise. Grab this and connect it to the bottom vector, grab this one, connect it to the top vector.

Leave it on add, then grab this add here and connect it to the bottom vector of gradient texture. Gradient texture’s going to be really handy. We’re going to take its factor and pipe it into this factor over here, and we’re going to pipe it into this one down here under multiply. We’re going to multiply it by one, so just leave that there. Grab this multiply, which is going to be driving the look of the fire, plug it into this bottom color ramp, and this will literally be the actual oranginess of the fire, so let’s go ahead and add a few things.

And, well, add what you think fire looks like. So I’m going to just click on Add. Right about here, I think things would get really bright. Maybe I want it a little bit more yellowy. Maybe this one’s a little bit too brown-like. This still feels a little bit too much green, kind of get it right in the middle there, really saturate it.

There we go. And white might actually be just a little bit too much, but let’s add just a little bit of a yellowy. There we go. Okay, so now from here, let’s go ahead and drag our color into color for emission. Under transparent and emission, we’re going to want to mix these, so emission goes down at the bottom, transparent comes on top, and finally, up here, we’re going to connect color to the factor.

And then, last but not least, we need to actually see it, so let’s connect these last two. Okay, this is a pretty crazy node structure. Let’s come over here and go to Rendered. And hey, almost! Looks like we need to rotate this a little bit. Let’s do that by 90 degrees. It’s a little faster on GPU, so you can switch to GPU there. And now let’s just mess with a few options.

You can see right away how I said this is controlling the, kind of the look of that fire. You can see you can almost make things kind of go up in flames if you’d like. If you come down over here, this is actually going to control the kind of infiniteness of the fire, this is how you would create that. So you could conceivably hit I, come all the way to the end, move it up, and then hit I again. Play this. Or you can actually hit play, and you get that fiery kind of look.

You can scale it, be a little careful, because you will kind of wreck a few things, so don’t go too crazy. These scales won’t do anything, it’s really this scale that controls kind of the strength of that. Over here, if you change the scale, you’ll get more of a control over the fire. Detail, of course, the lower the detail, the more blurrier it is, the higher the detail, the more richness you’ve got. You can distort it to get some pretty wicked kind of looks too.

So leave that kind of ghostly-like look. Now, over here, things don’t feel really that bright, right? And so if you want to, you can actually turn up the value. You get some pretty wicked things, but now, the downside is that you’re sending more light out than Blender’s actually registering coming in. So you just want to be careful about this, you don’t really want to blow out the screen as much as I’m doing right here. But for the purposes of this, it works. You can get more of an orangey kind of look here if you’d like.

Really saturate this kind of fiery look. Sometimes, it’s kind of fun to add a little bit of just a hint of bluish. Just a hint of it. Right at the end there. Just a hint of it, so we maybe we can say this is .9, and then this one’s kind of like 1.0. And if that still doesn’t feel right, just fiddle with these settings ’til you get something that you really enjoy.

Maybe .95, there we go. You can also mess with interpolation, just to kind of get different kind of looks. You can even kind of make it almost like 8-bit like fire. But I’ll leave it on linear for now. Now this one is kind of neat, because it’ll let you control the amount that goes up. Of course, you can make things really bright too, so be a little careful about that.

And you can kind of cut off some of this edging up here. But then again, you’re also going to potentially blow out the scene, so just be careful. And with that, there you go. You now have made fire using a node. And now, this wouldn’t be as cool if we couldn’t put it on a monkey, so let’s do that really quick. I’m just going to type in fire, I’m going to hit Z, X, Delete, Shift-C, Shift-A, monkey.

Zoom in on this monkey, click here, fire. Now, of course this monkey’s fire is coming from this direction, so we can try to rotate it. Let’s see if one of these will let us do it. There we go, maybe this guy here. I don’t think that these will let us do much. We’re going to have to adjust the scales here again.

And let’s just play it. Well now, because we’re animating on the X, that’s exactly why this is happening. So you can go ahead and right-click Clear Values, and instead what you want to do is either animate on the Z. In fact, let’s do that, Z, hit I, come all the way over here, let’s type in 10, hit I again. Click on play, or hit Alt-A. I’m actually going in the opposite direction. Come over here and say -10, hit I, now play that.

There we go. Now we have a flaming monkey. Pretty awesome, huh? And all generated through this simple, well, admittedly, actually really complex node structure, but still simple nodes when you think about it. It’s just a couple of mapping and a little bit of math to get our desired effect. So with that, you have now generated a flaming monkey, or a flaming fire shader that you can add to any object inside of Blender. Like all things, I recommend you get in there and play around and see what other cool stuff you can generate.

And until next time, this is David for Blender’s Tips, Tricks, and Techniques.

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