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Affiner

对功能的坐标进行仿射转换。

仿射转换在几何形状中保留线条和并行性。也就是说,在转换后转换之前平行的任何线都是平行的。另外,如果转换落在直线上的许多点,则产生的坐标将落在新坐标系中的直线上。

仿射变换包括翻译,旋转,缩放和反射。

输入端口

输出端口

参数

Examples

转换东部和北方的特点

To move features 500 units east and 1000 units north, use the following formula:

x'= 1x + 0Y + EARTING

y' = 0x + 1y + Northing

x' = 1x + 0y + 500

x' = 1x + 0y + 500

然后,您将在带内参数中输入A到F的相应值(例如,a = 1,b = 0,c = 500,d = 0,e = 1,f = 1000)

缩放功能集

To scale features by factor R, use the scale factor to the X and Y terms as follows:

x' = Rx + 0y + 0

y' = 0x + Ry + 0

To increase the scale by 10 times:

x' = 10x + 0y + 0

Y'= 0x + 10Y + 0

旋转特色

To rotate features, apply the appropriate cos and sin functions associated with the rotation angle to the X,Y coefficients:

x'= cos(w)x + -sin(w)y + 0

y' = sin(w)x + cos(w)y + 0

其中w =旋转角度。

所以,旋转30度,COS(30)= 0.866025,SIN(30)= 0.5, you would use:

x' = 0.866025*x + -0.5*y + 0

Y'= 0.5 * x + 0.866025 * y + 0

将一组特征旋转30度。

Combining Transformations

您可以将一组转换组合成一个公式,或者串联执行它们,以便更容易调试或编辑。例如,您的旋转可能更容易,然后在两个不同的带电器变压器中缩放,而不是尝试将它们组合成一个变换。当然,在一个转变中完成一切的一个优点将是速度。

Note:提示:右键单击工作区中的变压器,然后单击Show Summary Annotation。这使得可以轻松预览将使用的转换公式。

Usage Notes

  • Use the Affiner, rather than the Scaler, when scaling rasters. Because raster data is scaled around the data origin, not the coordinate origin, using the缩放者会导致意外的数据偏移)。

相关变压器

  • 还请看看亚疗手,which performs warping operations on the spatial coordinates of features. The AffineWarper is used to adjust a set of observed features so they more closely match some set of reference features.
  • 缩放者andoffsetter.都是带资源家的简化版本。例如:

x'= ax + by + c

and

y'= dx + ey + f

where一个= 1000andE = 1000.

In this case,x'= 1000x和y'= 1000y与缩放者相同。

Editing Transformer Parameters

Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, clickbeside the applicable parameter. For more information, seeTransformer Parameter Menu Options

Transformer Categories

Coordinates

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标签关键词:POINTCLOUD.