Join Rob Garrott for an in-depth discussion in this video Creating reflective or shiny surfaces, part of CINEMA 4D Essentials 4: Materials, Texturing, and Lights.
Reflections can be a beautiful component of your renderings, but they can have a dramatic impact on your render times. I have got a very simple scene here, and I've got a ball and the word SHINY, all sitting on a floor. I've also got some environment objects here that I've put under a null. I've got a Sky object, which is causing this gray background back here. I've got a very simple light pointing at the light target that's at the center of the world. We're not going to focus on the light at all right now. I want to just concentrate on the materials themselves. We'll leave the light alone.
The Reflection component of your materials can be activated in the material channels. So let's make a new material. I'm going to create a material by double- clicking here in the Material Manager, down in the bottom left of the interface. And let's apply it first to the sphere. I'm going to name this material Sphere. Let's take it across and add it to the sphere. Let's click on the material down here and then go to the Basic properties, and in the material channels I'm going to activate Reflection. Now when I do that, I get a perfectly mirrored ball.
Let's see what that looks like here in CINEMA 4D. Let's go Command+R or Ctrl+R on the keyboard. That renders the scene. Now you can see I've got a mirror ball that is reflecting the horizon, the sky above it, even the shiny type right behind it. It's a perfect mirror. I've also got the specular highlight, which is something you wouldn't normally see on a mirror. What you'd see instead is the reflection of the light source in the scene, and that's an interesting thing about CINEMA 4D renderings is that the lights don't normally by default show up in the renderings, which is unlike the real world.
In the real world, lights always show up in everything. Let's talk a little bit more about the reflections themselves. Let's add a reflection to the floor, and let's double-click in here to make a new material. Let's call it Floor. And then in the Basic properties, we're going to activate Reflection, and then we're going to drag the floor onto the Floor object. Now let's do a Command+R or Ctrl+R, and you could see that the floor is now reflecting the entire environment. In fact, it's reflecting the word SHINY.
One important thing to notice is that the word SHINY in the reflection is brighter than it is outside the reflection, the actual word. The reason for that is that the reflections are additive. They add into whatever material they're applied to. So this reflection of the word SHINY is being compounded by the gray of the sky. So the light gray of the sky is influencing the color of the reflection down here. So let's take a look at the Reflection properties. Let's click on the floor itself and go to the Reflection settings.
When you first add a reflection that reflection shows up at 100% brightness. So if we raise this window up here a bit we can see what's going on, the brightness with reflection is controlled by the Brightness setting and if I dial that down to, say, 18% or so--and let's do another rendering. But rather than hitting Command+R or Ctrl+R on the keyboard, it would be great if I could just have a window that automatically updated. Well, you do. It's called the Interactive Renderer. So if we click-and-hold on that and go to the Interactive Render Region, down at the very bottom, when we let go, we're going to get a new Interactive Render Region. And we can take that slider and slide it all the way up.
Now that we've got the quality all the way up, I can see what's going on here. The reflections are dialed down so much I can no longer see them in here, so let's crank them up a bit. Let's make them about 30% or so. We should be able to start to see the reflection. Let's crank it up just a little bit more, maybe 48%. There we go. Another component of the real world is that all surfaces have some sort of texture associated with them. Even the finest mirror, at a certain level, has a roughness to its surface. That roughness affects how reflections show up on the surface of your object.
To simulate that look, there's a great setting called Blurriness. Now, this is where the deadly part of reflections come in. This Blurriness setting is a huge render hit. We don't have a lot going on the scene, so it's not going to seem like a big render hit, but it can dramatically affect your render time. Notice that the last time it rendered, it took less than a second. Let's change the Blurriness up to something like 10%, and you can see that it still took only less than a second. Let's go ahead and raise that up and make it kind of big. There we go.
And let's take the Blurriness up to, say, 25%. There you go. It took quite a bit longer. So as you increase that Blurriness amount, the scene becomes more and more blurry, the reflections become more and more blurry, but the scene takes a lot longer to render. So let's bring that blurriness down to say, 5%. You can see a little bit of blur in there. You can see it's very tight reflection here, and as it fades off, it gets blurry. That's just what we want to happen. Let's take a look at the sphere now, and on the sphere let's go to the Reflection property and let's change the Blurriness to 10% there as well.
We'll see something quite a bit different. You see that now the ball appears to get a little bit smoother. A lot of times when I see artists adding reflections to their objects, they will leave the color on the default white. What that does is it tends to wash out the color of your object. So let's go to the color channel of the material on the sphere. So we select sphere in the Material Manager and then go to the Color option, and in the Color option, let's change it to green. That sounds good. So I'll put the Hue right there, crank up the Saturation, and it looks like nothing has happened.
That's because the reflection is overpowering our color underneath. So let's go to Reflection property and dial down the Brightness. As we dial down the Brightness, more of that green shows through. The reflections themselves are affecting the hue of the ball, the feel of the ball. It feels a little bit washed out. Let's go to the Reflection property and make it the same color as the color channel. So a really easy way to do that is to hold down the Shift key and click on the word Color up here, and now we can see both swatches at once. Now I can take this green and just simply drag it down onto Reflection.
The little highlight that was here on this outside of the ball, that's the highlight based on Specular Highlight, the bright point source that is showing up on the surface of the ball because of the relative angle to the camera. So now that we've added that color in, you can see that the ball got richer in color. Let's dolly in on this ball here and take a look at that. The next thing that we want to do is adjust something called the specular highlight. The specular highlight is this bright point source that shows up on all objects that are opposite a light source. So let's go to the Specular channel.
The Specular channel allows you to control the color, shape, and intensity of your specular highlight. So let's start off with the color. I want it to be not the same color green, but someplace in that range. So let's drag it over about here and then a nice brighter green version of it. Then you can see that it doesn't look like much has changed. Well, let's go and crank up that specular highlight and then change the Width from Height 51, roughly, all the way to 100. Now, you can see that it's gotten much, much brighter.
The shape of that can be controlled with the Width. A super-wide will spread out farther across the object; a super-tight one gives the object a more metallic feel to it; and the Falloff allows you to adjust the transition from the very peak to the sides. That shape made the object appear to have sort of an 8-ball spot on the side of it. Let's dial that Falloff back down to 0, and that's going to give us a nice tight spot. I can adjust the Width down a little bit more.
That's going to give us an even tighter spot. Let's go to the floor material and take a look at the Reflection property and see that I've got my Brightness down around to 48 range. Let's crank that up a bit so we can see a bit more of that. You'll see that, based on the color of the sphere, my reflection is being colored, and you can see that not only is my reflection being colored, but it's being blurred out as well. Here, near the base of the ball where it touches the floor, it's nice and crisp, and it fades out the farther the object gets away from that plane that it's hitting.
Reflections always do that. They start out very sharp and they kind of fade out, depending on the surface of the material that they are applied to. The render settings can give you something great results, and with the right control they won't affect your render times too much.
- Understanding material channels
- Applying materials via projection
- Limiting materials with selection tags
- Texturing type
- Using Falloff to limit the effects of lights
- Working with visible or volumetric light
- Painting on objects and textures with brushes in BodyPaint
- Hiding seams with projection painting