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Petal Extraction

'Petal Extraction' was created for a project in New York. The statue of liberty is located on an island south of Manhattan. On the east side of that island there's another island called Governors Island, which used to be the home of the coast guard. In 2013 the construction of a park started. The design of this park was based on petal shapes. The petals were drawn as polylines and are the alignment for kerb elements.To determine the position of the petals on the island data had to be extracted from the polylines. When the command starts the user has to pick a point. This will be the location of the legend. Then the user has to determine if the command has to produce an Excel file with the data. Then it's time to extract the data. The user is asked to select a petal shape, a polyline. When a polyline is picked the user has to tell which number is assigned to this petal. This number is used in the coding. The user can continue selecting polylines and entering numbers as long as needed. For every petal the command goes trough a number of actions. First it will make an inventory of the polyline to collect segment data. For this design most petals have one or more sharp corners with a specific radius which are used to enclose the kerb stones in between. These corners have a specific radius which is only used for these corners. The kerbs for these corners are called 'End Piece'. For every petal the command determines where the end pieces are located. It picks the one which is closest to the entrance of the preserved building on the site. This ensures a consistency in the coding of the petals because for every petal the coding starts there. If the selected petal is assigned with number 4, this end piece will be coded EP-4-I. EP for end piece, followed by the petal number and ending on the roman number 1 because it's the first end piece of the petal. The end piece covers 4 vertices on the polyline. The two middle vertices enclose a segment with the designated radius. The vertices preceding these two vertices is the starting point of the end piece. The coding off the vertices of the polyline start from there. This vertex is coded PT-4-I. PT for point, 4 the number of the petal and a roman number 1 for being the first point in the list. The second and third point are part of the end piece so the fourth point will be coded PT-4-II. The second and third point are not represented in the list. The fourth point is the starting point of the first segment which means every first segment of a petal is between PT-X-II and PT-X-III with X being the number of the petal. The coding of the segments is similar to the coding of the point and end pieces with one major difference. When the first segment of the petal is a straight line, the coding will be SG-4-L-I, when it's a curved line, it will be SG-4-A-I, with L for line and A for arc. All vertices, end pieces and segments are coded as such in a clockwise order. For every point the command will extract the coordinates. For every segment the command will extract the length, mid point and in case of a curved line the radius and centre point. The vertices will be represented in the list twice since they are the start of one segment and the end of another. The codes are listed in a table but also placed around the petal shapes. The three elements (end piece, point, segment) have their own coding but also their own icon. The points are marked with a filled triangle pointing to the point and accompanied by the point code. The segments are marked by a leader which points to the midpoint of the segment accompanied by the segment code, radius (if any) and length of the segment. Because the petals have irregular shapes the placement of the leaders have to be fine-tuned after using the command. The end pieces are marked by two triangles pointing to the centre of the end piece accompanied by the end piece code. This icon is aligned from the centre to the midpoint of the end piece. All other icons and text are alligned to the UCS.

Command summery

Entry:
PEX
Applies to:
polylines
Effect:
Retrieve data from selected polylines and places it in a legend and on leaders
Tags:
arc, block, centre, coding, data, end, end piece, Excel, extraction, leader, length, line, mid, midpoint, petal, radius, segment, start, table, text, vertex, vertices
Categories:
Excel, extractors, project based
Suitability:
No additional suitability information
Projects:
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