Reprojector
Reprojects特性协ates from one coordinate system to another.
Parameters
If the feature had a coordinate system, that system is used as the source of the reprojection, and the Source Coordinate System parameter to this transformer is ignored.
If the feature did not have a source coordinate system, and the Source Coordinate System parameter was unset, then the transformer only sets the coordinate system of the feature to the destination coordinate system, and the coordinates of the feature remain unchanged.
注意:If the source coordinate system is not fixed and may change from feature to feature, and the features themselves have been tagged with a coordinate system from the reader that produced them, then a single Reprojector may still be able to be used.In such a case, both the source and destination coordinate system can be set to the same value – the destination coordinate system – and the desired behavior will be accomplished.
If this parameter is set to No, then only the center points of the arcs or ellipses will be reprojected.Otherwise, if the feature came from a reader which supported this option, the arcs are converted to lines and ellipses to polygons and then reprojected.This option is has no effect on advanced geometry arcs and ellipses.
The Interpolation Type affects only raster data.Cell values are interpolated in order to change the raster to the specified size.
- 最近的邻居是最快的,但产生最差的图像质量。
- 双线性提供速度和质量的一个合理的平衡。
- 双立方是最慢的,但产生最佳的图像质量。
- 平均4和平均16有类似双线性性能,并且是数字栅格等的DEM是有用的。
The Cell Size applies only to raster features.
- 拉伸细胞:光栅的细胞大小将被调整,以保持重新投影的光栅相同数量的行和列的作为有在输入栅格。
- 方细胞:行和列的数目,以及所述间隔将被改变,以保持大约相同的细胞的接地面积,并形成正方形电池,其中水平和垂直的小区大小是相等的。像方形单元选项,保留单元格会改变的行和列,并保持细胞接地区的间距的两端的数量,而且会尽量保留原始细胞比例,考虑到造成重投影任何变形。
- 保留单元格:像方形单元选项,这个选项会改变的行和列,并保持细胞接地区的间距的两端的数量,而且会尽量保留原始细胞比例,考虑到造成重投影任何变形,。
Dynamic Coordinate Systems
If the destination coordinate system is specified as "_AZMEA_" or "_AZMED_", each input feature is reprojected to either an equal area or equal distance projection appropriate for that feature, respectively.In general, this causes a new coordinate system to be defined for each input feature.
Each feature remembers which specific equal distance or equal area coordinate system it has, and can be safely reprojected back to a normal (non-dynamic) coordinate system.
As an example:
- There is an input feature representing a point on the earth in LL-WGS84 (normal lat/long).
- The point is reprojected to _AZMED_ via a Reprojector with source LL-WGS84 and destination _AZMED_.
- The x and y coordinates of the point are extracted into x1, y1.
- Set x2 = x1 + 1000, and y2 = y1.
- Add a vertex to the point to make the line (x1,y1) -> (x2,y2).
- Reproject back to LL-WGS84 via a Reprojector with source _AZMED_ and destination LL-WGS84.
注意:Note that the source isignoredhere.We just chose _AZMED_ to help remember what is going on.Sometimes people prefer to set the source and destination both to LL-WGS84.
- Now we have changed our point into a line extending 1 km east of the original point, in lat/long.
Dynamic coordinate systems have the following limitation:
• Z is not considered, so areas or distances are best preserved for geometry at an ellipsoid height of 0 meters.
Example
Usage Notes
- This transformer works with both raster and vector data.
- This transformer is unaffected by raster band and palette selection.
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。
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标签Keywords: pointcloud