Table Of Contents


THIS SHADER IS DEPRECATED. PLEASE USE THE BUMP MAP SHADER INSTEAD.

Introduction

Normal mapping is a texture-based technique used to give the impression of sub-polygon lighting detail, without having to model it. It is controlled by a 'normal' texture, which is used to perturb the surface normal. Since only normals are perturbed, not geometry, it does not affect shadows.

The resolution of the normal map texture is important – you ideally want a one pixel per texel maximum resolution to get the best visual results. Magnifying the texture will blur the results and minifying will lessen the effect with distance.

The output of this shader is a perturbed normal.


General

Map

This is the texture map that contains the normals.

Unbiased Normals

8-bit integer texture maps normally store values between 0.0 and 1.0, but normals have component values between -1.0 and 1.0. When this is the case, the normals will have been pre-biased to fit into the 0.0 to 1.0 range. Check this option only when you know that the texture map is unbiased, meaning the normals were floating point and stored in the -1.0 to 1.0 range.

Flip Normal Y

This allows you to flip the y of the normal map, which is useful if the normal map was generated using a flipped uv coordinate system.

Scale Normal

This allows you to scale the resultant normal from the normal map, yielding a stronger 'bump' effect.



Advanced

UV Override

UV Set

This gives you extra options for filtering and defined the texture coordinates. For examples, see 'Image Sampler' document.

Elliptical Filtering

Maximum Eccentricity

This specifies the maximum eccentricity for elliptical filtering. The higher the value the better the results, but at the cost of performance. A value of 1.0 is the same as bi-linear filtering.

Alternate

U / V

This specifies whether alternate texture coordinate repetition should be reversed.

Repeats

Texture Repeats

This controls the repetition of the texture coordinates. Normally a texture is mapped with values 0.0 to 1.0, to cover the whole texture. A 'Texture Repeat' value of 2.0, for example, means that the whole texture will fit twice in the same 0.0 to 1.0 range. Values lower than 1.0 effectively act as magnification.

UV Remap

Minimum / Maximum

This specifies the range in which the texture coordinates will be remapped to.

Use Image Sequence

Allows you to use an animated image sequence for your normal map.

Normal Map Example

Here is an example of how a normal map can enhance the lighting detail of simple, flat geometry.



This example shows an un-textured surface, with a diffuse and glossy reflected spherical area light.



Now the same scene but with the normal map applied you can see how dramatically a normal map can increase the lighting detail without paying for the extra polygons.



The normal map that was used to create the effect.