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648 post(s)
#25-Nov-18 13:56

I test the script available in IMS town svg with area that use gps coordinnate manually create by mouse in mfd8 because need to make visible 30 cm accuracy.The IMS demo use a matrix transform to reproject all the layer inside a specific bounding box after some transformation . The transformation occur after load the page in the client side by running transform matrix include inside svg on path ( polygons points polylines) define inside svg .

I think since the coordinate has many digit before and after the virgule number are high so that browsers ( i test IE firefox chrome) have problems ( see above) to compute matrix on coordinate ( some rounded appear ? ) before rendering items inside area. Here i cut an area in small area with 30 cm border and no browser can render it except inkscape and manifold !! i paste the coordinnate of the top left small area to show the raw value .

So such drawing should be transform inside manifold to avoid the use of matrix transform in browser . The whole drawing could be include in a square of 200 meter border and i need to render it inside an area of 397 pixel or 14 cm ( 72 dpi) . I want that coordinate in manifold are locate on an interval beetween number 0 to 397pixel .

I think D3.js ll do this easely but wanted to to it in manifold so which tool i have to use to achieve this result in manifold ?


IMS svg Town.png


397 post(s)
#25-Nov-18 15:20

I played with Manifold SQL functions and vectors (FLOAT64xN types). This is mostly hobby project.

I have AffineTransform and PerspectiveTransform functions for single vectors (points).

I have not lifted these to Geoms. I may sometime.



648 post(s)
#25-Nov-18 22:15

thank's a lot i ll have to study before understand all the code .... D3.js have a good tutorial about this ( use most of the caseusa data like Responsive TopoJSON Sizing with d3.js . i ll try to search in the manifold documentation some fine article ! here aSVG documentation that show that IMS Town svg use svg tag polygon and polyline that use for trace shape The list of vertices (corner-points) that are two numbers, representing the x and y positions of the point in user coordinates; No concept of use of path data relative of absolute use by attribut d=" " . I do'nt know wich way is more efficient and really don't know why the svg rendering is wrong in the browser compare to manifold or inkscape !!!




648 post(s)
#25-Nov-18 22:46

IMS Svg Town sub article is locate at

The IIS IMS realtime demo on line is viewable at


I don't know if all browsers can in november 2018 rendering the svg content since specifcation of svg can change with time ... . Hope this post ll help end user understand all the technologies ( data protocol api language ) use by one example !!




648 post(s)
#05-Jan-19 14:53


A) it is take time to understand the inter relation beetween terms !!

Affine transformations are a subset of the projective transformations

1) Does matrix can be use for Affine and projective transformations ?

2) Can we replace the term projection by transformation ?

3) Matrix support only operator addition and multiplication ?

4) which geom transform can be achieve using matrix ?

B) how is manage x,y,z point in manifold 9

1) how can we write using text vector

2) how can we concat geom column and high column to a vector 3 ( floatx3) column ?

3) Is there native manifold9 matrix function ( pure SQL , or script programming ) ?

C) what are the relation beetween projection term use in gis and thos projectins : orthographic , perpective, Oblique ?

D) coordinate with projection and elevation

The geometry and geography types in both databases, PostGIS and SQL Server,

String geoWKT = "LINESTRING(1 0, 0 1, -1 0)";

Geometry geomWKT = Geometry.STGeomFromText(geoWKT, 0);

Geography geogWKT = Geography.STGeomFromText(geoWKT, 4326);

so refer to the function STGeomFromText, the API seem the same but apply to different object 

Geography /Geometry <-- STGeomFromText(String wkt, int SRID)

  • Geometry, where it assumes all of your data lives on a Cartesian plane (like a map projection);
  • Geography, where it assumes that your data is made up of points on the earth's surface, as specified by latitudes and longitudes.

Does values ( coordinate system) that come from satellite are call global geographic projection and the transformation from spherical/ellipsoid to flat plan ( conic cylindric ...) is call geometry projection ?





648 post(s)
#11-Jan-19 18:45

A3) Matrix support only operator addition and multiplication ?

A4 4) which geom transform can be achieve using matrix ?

here the transformation matrix.

Does manifold using transform in geom support shear ?

i don't find the name that manifold use to mean shear !




648 post(s)
#11-Jan-19 18:59



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