envelope operation

Syntax

envelope(direction, maxHeight, frontBaseHeight, frontAngle)

envelope(direction, maxHeight, frontBaseHeight, frontAngle, backBaseHeight, backAngle)

envelope(direction, maxHeight, frontBaseHeight, frontAngle, backBaseHeight, backAngle,
         sideBaseHeight, sideAngle
)

envelope(direction, maxHeight, frontBaseHeight, frontAngle, backBaseHeight, backAngle,
         rightBaseHeight, rightAngle, leftBaseHeight, leftAngle
)

envelope(direction, maxHeight, baseHeights, angles)

Parameters

Description

Creates a building envelope above each face of the current shape's geometry. Each edge of the face is classified according to the street.front, street.back, street.right, street.left, street.side selectors. Sides with the according baseHeights are then built perpendicular to the face. Finally, sloped planes are added at the top of each side, with the according slope angle.
Evaluation of the street.xxx selectors is based on the streetWidth attribute, see Auto-generated street width attributes. If the attribute is not available, component selection falls back to the object.xxx selectors.

Per edge control.One version of envelope allows for specification of baseHeights and angles per edge via arrays. The array must be in face-edge order, i.e. the first element is for the first edge of the first face, the second element is for the second edge of the first face, and so on. Shared edges are considered separately for each face. If the array does not contain enough elements, default values (0 for baseHeight and 90 degrees for the angle) are used. This allows to e.g. write
   envelope(direction, maxHeight, frontBaseHeight, frontAngle, backBaseHeight, backAngle)
as
   envelope(direction, maxHeight,
      comp(fe) { street.front = frontBaseHeight | street.back = backBaseHeight },
      comp(fe) { street.front = frontAngle | street.back = backAngle | all = 90 })


Basic envelope() operation parameters. The baseHeight and angle parameters of the other sides are analogue.


Example of street.front, street.back, street.right, street.left, street.side selectors applied on a lot of a block (with auto-generated streetWidth attributes).

Component tags

The operation automatically applies semantic component tags to the resulting face components:
"envelope.bottom"Blue: original face.
"envelope.side.base"Yellow: vertical base faces.
"envelope.side.slope"Orange: sloped faces.
"envelope.side.inner"Red: side faces from holes.
"envelope.top"Green: top face at max height.


For more information on working with component tags, refer to:
edgeAttr-faces

Related

Examples

Street-facing Slope

Lot-->
   setback(10) { street.front : color(0,1,0) 
                                FrontYard |
                 remainder    : Building }	              

Building-->
   envelope(normal, 50, 15, 30)
			
Envelope example a
The example code above creates a building envelope with a slope of 30 degrees facing the street-side. Eave height is 15 meters. Before creating the envelope, a front yard of 10 meters is split from the lot using the setback operation in conjunction with the street.front selector.

Copyright ©2008-2023 Esri R&D Center Zurich. All rights reserved.