发布关于PostGIS对于USD格式的拓展

我们非常高兴的发布为了一年一度的SIGGRAPH 2023发布关于为PostGIS支持USD格式的新拓展。

新添加了3个函数

ST_AsUSDA(geom geometry, usd_root_name text, usd_geom_name text, width float)
ST_AsUSDC(geom geometry, usd_root_name text, usd_geom_name text, width float)
ST_GeomFromUSD(format int, content bytea)

函数ST_AsUSDA和ST_AsUSDC用于转换PostGIS的geometry为USD数据，可以是文本格式的USDA用于调试，或者是紧凑的二进制USDC格式。所有的参数解释如下。

• geom, 输入PostGIS几何体
• usd_root_name text, USD默认Prim的名字，默认为World
• usd_geom_name text, 生成的USD对象Prim名字，默认为_geometry
• width, 默认为1.0，对于点Point和线Curve类似的geomtry, 此参数设置其宽度

ST_GeomFromUSD用于转换USD文件到GEOMETRYCOLLECTION，

• format，设置为1，输入内容为USDA，设置为2，为二进制USDC

代码仓库

• https://github.com/j-cube/postgis

分支

• bo-dev-usd

编译和安装的方式等同于PostGIS，一切按照PostGIS文档所描述进行即可。

感谢香港特新科技对本项目的赞助和支持。

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We're happy to annouce that the USD format in PostGIS is working for SIGGRAP 2023.

There are 3 major functions were created,

ST_AsUSDA(geom geometry, usd_root_name text, usd_geom_name text, width float)
ST_AsUSDC(geom geometry, usd_root_name text, usd_geom_name text, width float)
ST_GeomFromUSD(format int, content bytea)

The function ST_AsUSDA and ST_AsUSDC are used convert a PostGIS geometry to USD content, either in ASCII(USDA) format or binary Crate format(USDC). Both of them supports all geometry type. Here is the explanation for all arguments.

• geom, the PostGIS geometry
• usd_root_name text, default value is "World", generated USD has default prim with same name
• usd_geom_name text, default value is "_geometry", if a geometry contains sub-geometry, the all geometry object will be created with flatten USD prims with this name
• width, default value is 1.0, for Point or Curve-like geometry, it sets the USD width at USD geometry

ST_GeomFromUSD is is used to convert a USD content back to a set of geometry wrapped by GEOMETRYCOLLECTION.

1. format = 1 when content is USDA, format = 2 for USDC

Repository

• https://github.com/j-cube/postgis

Branch

• bo-dev-usd

Build and test as PostGIS document described.

Thanks for the support from Jadason Technology Ltd for this project.