The map receives from EsriGridReader is upside down ?

[leminhson]

Describe the bug A mesh imported from ArcInfo ASCII grid file using EsriGridReader function of fileio.py is displayed upside down.

Behavior The latitude of an Esri grid map received from EsriGridReader function is in the wrong order.

To Reproduce The ArcInfo ASCII grid files could be downloaded from : _https://ags.aer.ca/publications/MOD_2018_02.html_ (Alberta Geological Survey (2019): 3D provincial geological framework model of Alberta, Version 2 - metadata and methodology)

For example, a data file of bedrock topography top surface is a file: _cmh_02b_Pg_Pa_PHtop.asc

Data format: According to the web page https://desktop.arcgis.com/en/arcmap/10.3/manage-data/raster-and-images/esri-ascii-raster-format.htm:

The data component of the Esri ASCII raster follows the header information. Cell values should be delimited by spaces. No carriage returns are necessary at the end of each row in the raster. The number of columns in the header determines when a new row begins. Row 1 of the data is at the top of the raster, row 2 is just under row 1, and so on.

That means: the first row in data file has the highest latitude (corresponding to the top row on a map); last row in data file has lowest latitude (corresponding to the bottom row on a map)

Therefore, EsriGridReader function should read .asc data file from the bottom to the top, not from the top to bottom.

Screenshots Bedrock topology top:

A mesh is produced by EsriGridReader function (wrong latitude):

A mesh should be like this:

Desktop:

• OS: Windows 7 64bit
• Python Version: 3.8
• NumPy Version: 1.19.1
• PVGeo Version: 2.1.0

[banesullivan]

Wow, thank you for the detailed description of this bug and the details on the proper way to read the mesh! I will get to making a patch for this ASAP