Decal mapping is a powerful technique that allows you to apply flat textures
onto your 3D objects without needing to use UV mapping. You're basically applying
a sticker directly onto the object. So this works great for applying logos and
labels to packaging for product renders. You'll typically apply a Decal map as a
stacked material on top of another material that defines the base color for
your object. This works great because you can adjust the base color of the object
without affecting the Decal map. So let's take a look at the process of adding a
Decal map in Cinema 4D. To start, you're going to need to create a new material.
So we'll go down to the Material Manager and choose Create New Material.
Then simply double-click to open the Material Editor. We need to go ahead and
load our label into this material. So to do that, we'll make sure the Color channel
is active, and click on the dots here to load the texture. Select your label and
hit Open, and now you can see that we've got the color in here,
but we want to knock out the white portions of this label in order to see the
color of the tube underneath. For that we need to go ahead and apply an Alpha
channel. So activate the Alpha channel and load the same image into this channel.
So click the arrow here, go down to Bitmaps, and choose your label file,
again, from this menu of all of the bitmaps that are currently in your scene.
Now you can see that we've got a transparent label that we're ready to
apply onto our object. So to do that, we're going to drag this material either
onto the tube in the viewport, or directly onto the Tube object in the Object
Manager. Now you can see that this doesn't look quite right, and that's
because Cinema 4D defaults to UVW mapping. When you're applying a Decal map,
you almost always want to use Flat mapping. It still won't look quite right,
and that's because the Flat mapping isn't being applied in the right way.
To see how the Flat mapping is being applied, make sure the Texture tag is
active, as well as the object that the tag is applied to, and then activate the
Texture mode. You'll see a yellow grid here, indicating that the texture is being
applied sort of straight down from the top. So we need to go ahead and adjust
this. To make adjustments to the mapping, make sure the Axis tool is active.
We're going to go ahead and rotate our mapping, so we'll activate the Rotate
tool. We'll just drag this red rotation band here until this looks like it's going
to line up properly. If you hold down the SHIFT key while you drag, your rotation
will be limited to 10-degree increments, and you can see the current rotation value
right on top of the rotation gizmo. I want to rotate this to -90 degrees,
and then it looks like it's still backwards. So we'll take the green
band here and rotate that around 180 degrees. Now it looks like we're getting
somewhere, but I need to adjust the size of the label. So we'll activate the Scale
tool and scale it down. Cinema 4D defaults to tiling all of its textures.
So we need to turn off the Tiling so we only get one version of the label.
Activate the Texture tag, go into the Tag tab, and deactivate the Tile option.
Now we can use the Move tool and move this label back up. Now our
next problem is that the label doesn't match the proportions of the original
artwork. You could go back into the Scale tool and sort of manually try to fudge
this, but there's a better way. Simply right-click on the Texture tag and choose
Fit to Image. This is going to ask you for an image, and it's going to look at the
size of that image and adjust the Texture tag to match the ratio of the width and
height. So now we know our label is in exactly the right proportions,
and we can go into the Move tool and reposition it in order to get it exactly
where we want it on the object. And that's the basic process for Decal
mapping. Now, the good news is that we can make this even a little bit faster,
using the CV Import plugin available here on Cineversity. So let's look at the
process with CV Import. Simply select the object that you want to apply the image
to and go into the CV Import menu and choose CV Decal from Image.
Choose your label artwork and hit Open. Now you can see that this automatically
created a material that already has the image applied in the Color and the Alpha
channel. So all of that work has been done for us. It also applied a Texture tag
automatically, which will drag to the end of the list, and it automatically put us
into the Texture mode and the Texture Axis tool. So now we can go into the Rotate
tool and go ahead and do that same rotation to get this lined up properly.
Then go into the Scale tool and scale this down. You can also see that it
automatically did a Fit to Image for us, so that the Texture tag is the right
proportions for the label artwork. That is the process of doing Decal mapping in
Cinema 4D. Now, in the coming weeks, we're going to look at some additional quick
tips on how to optimize your Decal mapping, as well as some other ways that
you can optimize your product visualization workflow. If this quick tip
was helpful, please like, share, and visit cineversity.com for more great tutorials