Bump

Boxshot support both normal and relief (parallax) bump modes with some options allowing you to configure the effect. This tutorials explains all the bump modes and options.

Bump Modes

Boxshot supports three types of bump effect:

You can select the bump mode and configure its other options in the “Bump” section of the material panel:

Selecting bump mode in Boxshot

In order to use the bump effect you need to select bump mode and load a heightmap — the image that defines the relief of the surface. Darker areas of the heightmap mean “lower”, brighter areas mean “higher”.

Note that Boxshot does not support normal maps (yet), so if your bump image is not grayscale and red–violet–blue instead — that will not work and you need a grayscale heightmap image.

Normal Bump

When the “change normals” option is enabled, Boxshot only changes surface normals leaving the surface flat. This helps simulating liquid or some other uneven surfaces, where the displacement is not necessary:

Noise image as a heightmap with normal bump in Boxshot

Here a grayscale noise image is loaded as a heightmap and the normal map level is adjusted to make subtle “wavy” reflection.

Normal Map Level

The Normal map level controls how the heightmap affects normals of the surfaces. The higher the level, the more normals are changed. Here is the same sphere with the same noise heightmap, but with a higher normal map level:

Higher normal map level changes normals more

When “Change normals” bump mode is used, “normal map level” parameter usually needs to be adjusted in order to get a proper result.

Relief Bump

Another bump option in Boxshot is relief bump, which comes in two modes: push and pop. Both act the same, so we’ll start with the latter and explain the difference later below. For relief bump we’ll need a more specific heightmap, like this:

Heightmap with white text on black background

Let’s start with a simple blue plastic sphere and apply the bump texture leaving the “change normals” bump mode:

Normal bump on plastic sphere

You can see the bump effect on the surface, but it is pretty subtle as only the reflection is really changed. In order to get a stronger effect we need to see the shadows, as well. Let’s now change the bump mode to Change relief (pop):

Relief (parallax) bump on plastic sphere

Now you see the letters actually stand out of the sphere surface. You can adjust the Relief height option in order to control the effect. At some point you might also want to adjust the normal map level, as in some cases high normal map level may lead to issues like this:

High normal map level may create visual artifacts on relief map

This happens when the normals are two steep compared to the relief and rendering goes the wrong way. Reducing normal map level usually helps to sort this out.

Relief Bump Is Not Displacement

It is important to note that relief bump effect is not a displacement, so no geometry is really changed. You can check this by rotating the sphere a bit:

Relief bump is just a visual effect, not displacement

Boxshot simulates the relief by changing the look of the rendered elements, but only where the elements are actually rendered. As the sphere itself is still round, Boxshot cannot extend the relief beyond the sphere’s boundaries on the screen.

Keep an eye on the edges of objects when using strong relief bump effect.

Relief Bump: Push vs Pop

When using relief bump you configure the relief height using one of the parameters in the materials panel. The question here is where that height goes: into the surface or out of it? Boxshot lets you do both, so the “push” mode is when the relief goes inside the object and the “pop” mode is when the relief goes out.

Black areas of the heightmap will be rendered relief height deep if the bump mode is “push” and exactly on the surface if the bump mode is “pop”. Same for the white areas: they will be rendered on the surface if the bump mode is “push” and relief height above the surface if the bump mode is “pop”.

The relief bump mode doesn’t really matter if you apply it to the whole object like the sphere above. You can try switching between push and pop modes and seeing for yourself as it simply moves the relief a bit here or there. Most of the time you can safely use the “push” mode bump for objects.

As for “pop” relief bump it works best for creating effects like stamps, water drops, dew etc. When all the relief should stay on top of the surface and then the relief is applied as a decal, the “pop” bump mode works best.

Water drops simulated with relief bump decal in Boxshot

Here a transparent decal is applied with the relief bump to simulate the water drops on a glass.

You can read more about bump decals in our Bump Decals tutorial.

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