Bump Mapping

What is Bump Mapping?

Bump mapping refers to a specific technique used in computer graphics by which bumps and shadows are simulated on a smooth surface of a 3D object to give rough textures to it.

Technically, bump mapping signifies a video accelerator technique that uses the height-field method. In simple words, in this technique, irregularities are created on a surface via shading, which would have looked plain and ugly otherwise.

Understanding Bump Mapping

What is Bump Mapping

Bump mapping refers to a texture mapping process followed in computer graphics in which the surface normal is perturbed to simulate bumps and wrinkles on it.

Introduced in 1978 by James Blinn, there are a few specific principles followed in the bump mapping technique. These are:


This process is also characterized by the following:

Through the bump mapping process, additional features on the surface of the object are also altered. For this, extensions are used, such as:

The most significant limitation of bump mapping is that shadows and silhouettes are not affected by this process since the underlying surface is not modified.


There are basically two methods for bump mapping.

Using a height map:

In this method, which was invented by Blinn, a height map is used to modify the normal and simulate bumps.

In this method, a few specific steps are followed before making the lighting calculation for each pixel or visible point on the surface. These are:

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This creates a surface with real depth, and the algorithm ensures that its appearance changes when the lights move around the scene.

Using a normal map:

The second method followed in bump mapping is by using a normal map containing the modified normal for every visible point on the surface.

The normal is specified directly and is not derived from the height map. This produces more accurate and predictable results, thereby helping the users to work with the scene.

This is typically the most commonly followed method in bump mapping today.


Today, bump mapping is used in a wide range of programs and applications, including, but not limited to:


There are basically two popular types of bump mapping, such as:

Emboss bump mapping

Also referred to as two-pass emboss bump mapping, the characteristics of this type are:

Environment mapped bump mapping

Often referred to as EMBM, the characteristic features of this type of bump mapping are:

Both of these types help in changing the dimensionality and appearance of the surface normal of the 3D object by adding different characters and details, including, but not limited to:

All these remove the smoothness of the surface and make it look more attractive.

What Does Bump Mapping Do?

Bump mapping typically creates illusions of texture and depth in computer graphics while using a model with a three-dimensional surface. It creates these textures artificially on the surface of the 3D objects by means of a set of grayscale.

In addition to that, bump mapping also does a whole lot of other things, which include but are not limited to the following:

In short, bump mapping makes an image look more realistic, which helps enhance the visual pleasure of the user while working with images or playing games on computers.

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Bump Mapping Vs Normal Mapping

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So, now you know that bump mapping refers to the process of adding a texture or a texture map on the 3D surfaces in computer graphics.

You also know about its different types, its uses and methods used to create the textures on the smooth surface of a 3D object.