I am using a path distance function to calculate distances from a set of source cells on a land use raster. Unfortunately, my land use raster and my other inputs have different cell sizes. The land use raster has 300 m pixel sizes and my other inputs have ~90m pixels. I would prefer to avoid resampling. I would also like the entire area of the source pixel to be represented as 0 on the resulting distance raster. I will be pulling out individual pixels from the land use raster to use as source cells, and the easiest way to do this is to convert to points . However, given the size differences in the pixels, I'm not sure that it would be accurate to represent the source cells as points. I was thinking of using polygons instead (which can be expanded to the 300 m size of the pixel), but I'm unsure of how the tool will handle the polygons when calculating distance. If the tool will use the centroid of the polygon rather than the edges, then using a polygon is no improvement over using a point to represent the area. I had also considered using a raster as an input, but, again, I'm not sure how the tool will handle the size differences.

Essentially: Does anyone know how exactly ESRI's distance tools handle different inputs during execution when the source inputs may not match the analysis cell size or may span across multiple pixels in the analysis cell size? How does the program handle resampling and/or source cell definitions in these cases?

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    According to its help page, the pathdistance tool ought to work like costdistance. The costdistance help page provides a small example where the source in fact is a set of polygons, not just a single cell, so by inspecting this example you can satisfy yourself concerning what it actually does. – whuber Jan 23 '13 at 17:00
  • I had been through those examples before. However, while they show a general example using polygons as input in the path functions and the line the actual path drawn by the program, I haven't been able to find anything explaining what happens in the cost raster generated by the tool. In this case I'm interested in the distance raster, not just the least cost path. – Jezibelle Jan 23 '13 at 17:32
  • I don't understand your comment: the example on the CostDistance page shows the entire output cost grid. – whuber Jan 23 '13 at 18:17
  • In the example on that page they're not using polygon inputs - if they are they're the exact same size as the analysis cell size. I want to know what happens when the polygons span across multiple pixels – Jezibelle Jan 23 '13 at 18:36
  • Sorry, if the original question was unclear. I've edited it to try and make it more specific – Jezibelle Jan 23 '13 at 19:12

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