Routine Performed for Each Origin Cell There is another set of loops that cycle through Origin Cells...
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Routine Performed for Each Origin Cell There is another set of loops that cycle through Origin Cells once the D8 Neighbor procedure completes
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Transcript of Routine Performed for Each Origin Cell There is another set of loops that cycle through Origin Cells...
Routine Performed for Each Origin Cell
There is another set of loops that cycle through Origin Cells once the D8 Neighbor procedure completes
origin
STOP
1 1 2
2
2
Get data from all layers that corresponds to current cell coordinates, and store in temporary array(s).
Using a dynamic array probably best since the number of rows is unknown
arrays/lists
1. Extract Data to Array(s)
origin
STOP
1 1 2
2
2
Movement:Origin Pixel Value = 1“1” Translates to (c+1, r)
2. Move
'X Coordinate CodesxC(1) = 1xC(2) = 1xC(4) = 0xC(8) = -1xC(16) = -1xC(32) = -1xC(64) = 0xC(128) = 1
'Y Coordinate CodesyC(1) = 0yC(2) = 1yC(4) = 1yC(8) = 1yC(16) = 0yC(32) = -1yC(64) = -1yC(128) = -1
For N = 1 To 8 NextPixel = pPixels(c + xC(N), r + yC(N)) …Next
???If statement vs array for translating???
origin
STOP
1 1 2
2
2
Get data from all layers that corresponds to current cell coordinates, and store in temporary array(s).
arrays/lists
3. Extract Data to Array(s)
origin
STOP
1 1 2
2
2
Movement:Origin Pixel Value = 1“2” Translates to (c+1, r+1)
2. Move
'X Coordinate CodesxC(1) = 1xC(2) = 1xC(4) = 0xC(8) = -1xC(16) = -1xC(32) = -1xC(64) = 0xC(128) = 1
'Y Coordinate CodesyC(1) = 0yC(2) = 1yC(4) = 1yC(8) = 1yC(16) = 0yC(32) = -1yC(64) = -1yC(128) = -1
For N = 1 To 8 NextPixel = pPixels(c + xC(N), r + yC(N)) …Next
???If statement vs array for translating???
origin
STOP
1 1 2
2
2
Get data from all layers that corresponds to current cell coordinates, and store in temporary array(s).
arrays/lists
3. Extract Data to Array(s)
origin
STOP
1 1 2
2
2
4. Stop
A stop condition is met, we are at the edge
origin
STOP
1 1 2
2
2
Once STOP is met, the array(s) can be combined in many ways and then the result(s) are written to the location of the origin cell on the output raster(s).
arrays/lists
5. Calculate
01234
01234
01234
01234
The flow path sequence is preserved in the index of the array
Math Machine
output raster(s)
1 set per origin pixelWrites to corresponding cell
6. RINSE AND REPEAT
Data are cleared from the temporary arrays, and we start with a new origin pixel
The term Origin Pixel really refers to a starting location in an array, because the whole time we are dealing with arrays
