I have a streetmap with the coordinates of some speed limit signs (which mark either the beginning or the ending of a speed limit and hold the applicable speed limit in km/h). With regard to the direction of driving, the signs are always positioned on the right side of the road:
What I want to do now is to create a new line layer which shows the speed sections (the length in km of the speed section and the speed limit in km/h itself).
In order to do that, I guess I will have to create normal vectors with the points of the speed signs and the streets itself in order to get intersections directly on the streetline. I know how to do that by now. But how can I "drive" along the streetline to sequentially check each speed sign in order to extract the speed sections? Let's take the picture above as an example: If I start south at the beginning of the 70 km/h speedsection, I have to drive north (because it is the driving direction of the street) and check each speed sign along the line for the end of the speed section. After that, I search for the next beginning speed section and so on.
How can that be realized? Please comment if you need more details on that issue.