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Road Editor

Click&drag vertices of the black control polygon
Drag them out of the window to delete
Click&drag the middle of a black edge to insert a new vertex
Keep r pressed and click&drag to edit the radius of a control circle
Press N to toggle the display of the IDs of the control vertices
Press SPACE to toggle the display of the black control polygon and circles
Press A to make all edges vertical or horizontal
Press C to recenter and rescale the model to fit in the window
Press R to read a road from file

Press F to toggle the shading of the yellow road
Press m to toggle the display of the blue median curve
Press c to toggle the display of sample circles
Press a to toggle the display of the brown reansversal arcs
Press l to toggle the display of the brown reansversal line
Press h to toggle the display of the brown reansversal hat (ines fromn median to the borders)
Press d to toggle the display of the distance field from the median (slow)
Built by Jarek Rossignac with Processing. Source code: roads pv2D