I'm writing Shapefiles through Fortran with success, writing points, lines, and polygons. The next step in this project (separate from the previous step) is to write grids such that each cell can be coloured to correspond to a value/field. Seems to me that a raster would do this perfectly, if my data was simply rectilinear (the Esri ASCII raster would be fitting). However, I'm working with curvilinear grids, and each cell does not have the same size as the next. Additionally, the grid might be rotated, depending on the location. For example, say I have a river that doesn't necessarily run just North-South. The grid is created based on the river and is rotated to match the river. Parts of the river that are especially twisty or have a varying river bed will have smaller or more cells to compensate. And then the grid would be coloured accordingly, depending on temperature, or salinity, or whatever. I'd be able to do this easily as well in Matlab or something but the client specifically wants to be able to view everything in ArcGIS 10.1/10.2.
I'm not sure how to go about this, I've tried searching this site and the internet, using combinations of words like 'non-uniform', 'curvilinear', 'cell sizes', etc. but I haven't managed to find what I need. I've attached an example image of what I'm working with and what I'm looking for. Notice that the cells are not all the same size and are also at an angle.
I would have added tags like 'non-uniform grid' or 'curvilinear' but I can't yet, so hopefully this sentence helps with searchability.