patmalcolm91 / qgis-plugin-flow-map-arrow-curver Goto Github PK

Allow the user to input formulas for the pixel width and radius, which then would be used with the map scale to calculate the actual values. Upon creation of the layer, the graphic properties could also then be automatically adjusted to match.

Implement FlowMap.reduceFlowLineIntersections() and FlowMap.moveFlowLinesOffNodes().

Remove existing checks in force calculation functions and perform a single check at the very beginning, filtering out reversed flows if necessary.

If no node layer is given as input, allow the option to generate a node layer from the lines. Include calculation of flows (in, out, and total), so node size can be displayed based on these values.

Several of the force calculation functions can be parallelized to improve performance.

Trace:

File "/home/patrick/.qgis2/python/plugins/FlowMapArrowCurver/JennyAlgorithm.py", line 713, in run
fm.reduceFlowLineIntersections()
File "/home/patrick/.qgis2/python/plugins/FlowMapArrowCurver/JennyAlgorithm.py", line 565, in reduceFlowLineIntersections
if inAndOutFlows[i].interesectsFlowLine(inAndOutFlows[j]):
File "/home/patrick/.qgis2/python/plugins/FlowMapArrowCurver/JennyAlgorithm.py", line 114, in interesectsFlowLine
intersect = Geometry.findIntersectionOfLineSegments(p1, p2, p3, p4)
File "/home/patrick/.qgis2/python/plugins/FlowMapArrowCurver/Geometry.py", line 269, in findIntersectionOfLineSegments
mBetween = (y3 - y2)/(x3 - x2) # the slope between two points on different lines
ZeroDivisionError: float division by zero

Large datasets take a very long time to process, and the progress dialog doesn't always appear, so QGIS appears to be frozen. When selecting a layer, QGIS should warn the user if the number of flowlines is very high.

Get algorithm working reliably.