Bump Map 凹凸贴图

Introduction

引言

The Redshift Bump Map node supports both height maps for bump mapping and object space or tangent space normal mapping. Bump / Normal mapping is a texture-based technique used to give the impression of sub-polygon lighting detail, without having to model it.

红移凹凸贴图节点支持凹凸贴图的高度贴图和物体空间或切线空间法线贴图。Bump/Normal 映射是一种基于纹理的技术，用于给出子多边形光照细节的印象，而无需对其建模。

The resolution of the these textures are 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.

这些纹理的分辨率非常重要——理想情况下，每个纹理最大分辨率需要一个像素才能获得最佳的视觉效果。放大纹理会使结果变得模糊，缩小效果会减少距离。

 

Bump Mapping

凹凸贴图

Bump maps are controlled by a height map texture which is used to perturb the surface normal. Since only normals are perturbed, not geometry, it does not affect shadows. Bump maps do not contain directional information.

凹凸贴图由高度贴图纹理控制，用于扰乱表面法线。因为只有法线受到扰动，而不是几何体，所以它不会影响阴影。凹凸贴图不包含方向信息。

Normal Mapping

法线贴图

Normal maps are 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. Normal maps contain directional information.

法线贴图由一个用于扰乱表面法线的“法线”纹理控制。因为只有法线受到扰动，而不是几何体，所以它不会影响阴影。法线贴图包含方向信息。

General

将军

Enabled

启用

This enables the bump map effect. When this is disabled, the normal that is generated is just the surface normal.

这使凹凸贴图的效果。当这是禁用，正常是生成的只是表面法线。

Input Map Type

输入地图类型

• Height-Field:  高度-场地:This sets the Bump Map node up to use greyscale height based texture maps for bump mapping. 这将凹凸贴图节点设置为使用基于灰度高度的纹理贴图进行凹凸贴图
• Object-Space Normal:  物体-空间常规:This sets the Bump Map node up to use object-space normal maps for normal mapping. 这将设置 Bump Map 节点，以使用对象空间法线贴图进行法线贴图
• Tangent-Space Normal:  切空间法线:This sets the Bump Map node up to use tangent-space normal maps for normal mapping. 这将凹凸贴图节点设置为使用切线空间法线贴图进行法线贴图

Object-Space vs Tangent-Space Normals

物体空间法线与切空间法线

Object-Space Normal maps contain normal information specific to the object it should be applied to. In Object-Space the up axis is directly tied to the up axis of the object itself and therefore using an Object-Space Normal map on any object other than the one it is intended for will not look right.

对象-空间法线贴图包含应用于的对象的法线信息。在 Object-Space，向上的轴直接与物体本身的向上轴相连，因此使用物体空间法线贴图对任何物体而不是它所要找的物体都不会看起来正确。

Tangent-Space Normal maps contain normal information that can be applied to any object and behave properly. In Tangent-Space the up axis is relative to an objects surface normal and therefore using a Tangent-Space Normal map on any object will behave correctly.

切空间法线贴图包含可以应用于任何物体的法线信息，并且行为正确。在相切空间中，上轴是相对于物体表面法线的，因此对任何物体使用相切空间法线贴图都是正确的。

Below is a comparison of an object-space normal map and a tangent-space normal map. First the object-space and tangent-space maps are demonstrated on their intended source geometry, both look perfect. In the second example the same shader is applied to a flat plane which is where you can see how the object-space normal map perturbs the plane's normals in such a way that it does not look good. Comparatively the tangent-space normal map looks much better since it is relative to the surface normals of the plane.

下面是物空间法线贴图和切空间法线贴图的比较。首先，对象空间和切线空间地图在其预期的源几何图形上进行了演示，看起来都很完美。在第二个例子中，同样的着色器被应用到一个平面上，在这个平面上，你可以看到物体空间的法线贴图是如何扰乱平面的法线的，以至于它看起来并不好。相比之下，切空间法线贴图看起来要好得多，因为它相对于平面的表面法线。

Input

输入

Connect a texture sampling shader node here to set the map input.

在这里连接一个纹理采样着色器节点来设置贴图输入。

Height Scale

高度比例

This scales the height value that is read from the texture. A value of 0.0 effectively disables the technique, yielding just the surface normal. Greater values increase the bump effect. Negative values invert the direction of the bumps. The default is 0.010.

这可以缩放从纹理读取的高度值。0.0有效地禁用了这项技术，使得表面正常。更大的值会增加凹凸效应。负值颠倒颠簸的方向。默认值是0.010。

Affected By Object Scale

受物体尺度的影响

This option forces the resultant bump vector output to scale along with the objects scale. Disabling this option will essentially remove any scaling bias, yielding more predictable results when blending bump maps and normal maps.

这个选项强制结果凹凸矢量输出随着对象缩放而缩放。禁用此选项将基本上消除任何缩放偏差，在混合凹凸贴图和法线贴图时产生更可预测的结果。

Change Range / Remap

更改范围/重新映射

Old Range Min / Max

旧靶场最小/最大靶场

The range of values that are read from the displacement/bump texture.

从位移/凹凸纹理读取的值范围。

New Range Min / Max

新航程最小/最大

The new range the values will be mapped to.

值映射到的新范围。

Unbiased Normals 无偏正常值

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.

8位整数纹理映射通常存储值在0.0和1.0之间，但法线的组件值在-1.0和1.0之间。在这种情况下，法线将被预先偏移，以适应0.0到1.0的范围。只有当您知道纹理贴图是无偏差的，也就是说法线是浮点的，并且存储在 -1.0到1.0范围内时，才选中此选项。

Flip Normal Y 翻转正态 y

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

这允许您翻转法线贴图的 y 轴。这是有用的，如果法线地图是使用翻转的紫外线坐标系生成的。

In the examples below note that the lighting has not changed but where the specular highlights appear on the sphere has been inversed.

在下面的例子中注意到照明没有改变，但是在球体上出现的高光已经被反转。