Join Craig Whitaker for an in-depth discussion in this video Texturing the flag, part of VFX Techniques: Creating a CG Flag with Nuke X and CINEMA 4D.
With the flag simulation cached and in place along with the checkerboard, we're clear to move forward and start developing the texture and the shader for our flag. So, with the checkerboard texture, let's open that up, and in the color channel let's go to Texture > Load Image. And let's pull in our flag. Yes. Craig's food fest. Let's click back on the tag. And go to Tags > Fit to Object. This is going to snap the entire texture to the face of our flag.
And why is that working so well? Well, it's working that way because we designed our flag texture in Photoshop with the same aspect ratio, the 2 to 1 ratio, that we have set up for our flag. So that works out really well. So let's open up the texture and take a look. Let's go into the Specular channel. Now, we don't want the specular to be very wide, we kind of want it to be sharper and a little bit more focused, so we'll pull the height way up and pull the width down a little bit. And let's see, all right good, so we're getting some specularity here, which is good.
Getting some nice, tight, focused specular. Let's also go in and load our flag into the channel. This way the specularity takes on the shading of the flag texture and doesn't just give us a pure white texture. So we can crank that up a little bit. There, and we get some specularity that takes on the exact same colors as the flag, which is great. Good, moving along. Turn the reflection channel and bring that down to black. Bring our brightness down and we'll put a fresnel shader in the texture and we'll lower that a good amount.
We want it to reflect objects in the environment, in the case our sky, but we don't want it to appear glossy or shiny. So I'm just going to do a couple quick test renders here. There we go. So we can start seeing that it's picking up some reflection there. Now, right now there is nothing in the environment for it to reflect except itself, so let's change that. Go to a sky object. Let's make a new texture. We'll call this sky and we'll drag it onto our sky object. From here we will double-click.
And let's turn off the color inspect and go to luminance. And we'll turn on a gradient texture. We'll switch that to V and then we're going to pull this is a little bit just so we can make sure that we have the right colors in the right place. Good. So black, we'll actually lift that to kind of a light grey, and I'm doing that because the colors in the bottom that it will be reflecting are kind of like a brownish-grey color. So actually, we could probably add a little brown into that.
Not much. And then, we have this blue sky up here, but we don't want to go super blue. If we want, we can actually color pick a light blue color here and leave that. There, so now we can spread this back out and get the full range, blue in the sky up here, down to this brownish-gray on the bottom. Now we can activate our sky object. We'll right-click, Cinema 4D Tags > Compositing, uncheck Seen by Camera. But still Seen by Rays and Reflections. There we go.
So now it's reflecting the sky. Let's go down to the flag shader again, open that back up. And we will blur our reflections because we don't want those to appear sharp. We want those reflections to kind of be smeared out a little bit. We can actually try to bring some of this reflection back up. There we go. Good. So I'll just bring that up and I'm just scrubbing though here a little bit to find some other spots. Maybe when it goes underneath. Let's see here, where it kind of dips back under a little bit. Do a test of that. Good. So that feels good, that feels nice in there.
Let's add a bump channel. So we'll go to the Bump > Texture > Noise. Now obviously that looks wrong right off the bat. Way too big. So we could just lower our strength. You know, down, something like this, but the scale is still wrong. So let's open up the Noise. Go to Global Scale. We'll bring that down to maybe like 3%. The black and white values may have too much contrast, so we'll open up the black and lift that a little bit. There we go. Something like that. And last we'll go to the Illumination, and we'll change from a Blin to Oren-Nayer to get more of a cloth-like shader.
There we go. So looking pretty good. So that's good to get started. Now, what we'll have to do is as we move through the rest of the project and we start adding lights, we'll most likely have to come back and tweak our texture to accommodate our lighting information.
- Collecting reference materials
- Planning and blocking out the shot
- Analyzing and tracking the footage
- Solving the tracked shot and setting up the environment
- Creating and adjusting the cloth simulation
- Texturing the flag
- Rendering passes from 3D
- Color grading and adding grain