Creating Geometries¶ Simple Geometries:¶ StSpatialCommand(functionToApply, layer, outputLayername)¶ Parameters: functionsToApply (type) – Choose between Kernel, BBox, Centroid, Convex Hull layer (QgsVectorLayer) – input layer outputLayername (string) – output layer name The Kernel is the sub-area wi...

Extracting Intersections

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khartwell (15 déc. 2017)

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Extracting Intersections¶ T4QG offers two diferent methods for extracting the open space at intersections. Intersections are here defined by points (i.e., a QgsPoint Layer). You may already have a a point layer available, or you may have to extract it from lineString data using STToRoadsSectionsNode...

Creating Graphs

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khartwell (15 déc. 2017)

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Creating Graphs¶ This section explains the basic built-in functionalities pertaining to urban graph analysis. The two principal elements of an urban graph are vertices and edges. Generally, a vertex corresponds to the intersection of mutiple edges. In Urban Planning, vertices correspond to intersect...

Spatial Attributes

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khartwell (15 déc. 2017)

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Spatial Attributes:¶ Morphological Indicators :¶ STSpatialAttributeCommand(functionsToApply, layer, outputLayerName).execute()¶ Parameters: functionsToApply (list) – A list of one or more of the following parameters to be calculated : Area, Perimeter, NbConcavities, PerimeterConvexityDefect, AreaCon...

Welcome to the T4QG Documentation Page

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khartwell (15 déc. 2017)

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Welcome to the T4QG Documentation Page¶ Welcome to the Tools 4 QGis Documentation home page. T4QG is a Quantum-GIS plugin created at the CRENAU Laboratory. The aim and scope of this tool is to assemble morphological indicators pertaining to the urban open space. The following pages present the eleme...

Making Solar Envelopes

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khartwell (15 juin 2017)

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Making Solar Envelopes¶ Pre-processing¶ Before being able to perform a solar envelope analysis, several operations need to be done. This analysis uses 2D data (eg: building footprints). First, select the building on which the analysis is being done. T4SU only accepts one building (ie: one polygon)....

Lines of Sight

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khartwell (30 mai 2017)

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Colored Lines of Sight To visualize the visibility of an individual facing in a certain direction, one can use lines of sight. "PColoredLinesOfSight3D" does so by selecting a point in space and a direction to "see". As rays are cast towards this point with a given aperture, the rays are colored in ...

Understanding Solar Radiation

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khartwell (23 mai 2017)

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The Science Behind : Solar Radiation 1.2. Initial Definitions : Solar Energy is the amount of energy sent by the sun, meaning the maximum energy received by the Earth, without taking into account climatic conditions (clouds), date or time of day which impact the angle of the surface relative to the...

Sky Maps, Building Facades and Sunny Sky Maps

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khartwell (23 mai 2017)

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9. Sky Maps Sky Maps are a projection of the visible sky at a single point in space onto a onto a half-dome, who's center is at the point of study. In the case of a 2D-projection, the dome is projected a second time onto a disc, who's circle matches the point of origin. Sky Maps work in a similar f...

Sky and Sun View Factors

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khartwell (23 mai 2017)

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10. Sky View Factors 10.1. Calculating the Sky View Factor¶ The Sky View Factor (SVF) is used in the evaluation of the impact of urban geometry on the micro-climate, specifically temperature and the Urban Heat Island phenomenon. Sky View Factors help in the comprehension of an area’s potential direc...

Direct Solar Irradiation

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khartwell (23 mai 2017)

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11. Viewing Direct Solar Irradiation along a Path The city landscaping team has a new shipment of flowers, and they must decide where to plant them. They already have a general idea along a new pathway, using planters that reach two meters high so they can be seen from afar. These plants are very fr...

Understanding the Sky View Factor

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khartwell (23 mai 2017)

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1. The Science Behind : Sky View Factors 1.1. A Short History One of the earliest SVF calculations were made with the help of digital cameras mounted with Fisheye lens. The masks were then delineated manually and the SVF is calculated with Steyn’s method [1]. Other raster-based calculations were lat...

Loading data into SketchUp

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khartwell (15 mai 2017)

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3. Loading your data into SketchUp¶ Once you have installed t4su, click on FileImport.... As you click on the available file types, you can notice that several new types of imports are available : You can import geometries : ASCII Grid file types (*.asc) Solene output files (*.cir) WellKnownText (*....

Understanding Ray Casting and Isovists

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khartwell (15 mai 2017)

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Ray Casting and Isovists¶ The Science Behind Isovists: A Short History¶ Although isovists are considered to have been first set in theory by Benedikt in 1979 [1] (a first mention of them was made by the same author in 1977 [2]), their first appearance in scientific litterature was a paper by Tandy...

Preparing your Model

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khartwell (15 mai 2017)

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4. Preparing Your Data¶ Learn to pre-process your geometries before performing any analysis. 4.1. Extruding Heights from your Geometries¶ Once you have loaded your data, it will appear on your screen as well as in your Layers. The geometries are, for now, flat. To analyse our data, we must first ext...

General Tips to Start

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khartwell (15 mai 2017)

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5. General Tips to Start¶ T4SU offers many features that allow for an automatic selection, modification, creation or visualization of information, for a fast and easy way to treat and analyse our data. Many of these techniques will be used again in examples throughout the manual. 5.1. Selecting Geom...

Sampling Methods

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khartwell (15 mai 2017)

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6. Sampling Methods¶ T4su offers a four ways to sample your geometries. Sampling is very useful whenever a phenomena may be better studied with spatial discretization. whether they be flat surfaces or lines. They can be found by clicking Extensions t4su Edit : 6.1. Sampling the Bounding box¶ As with...

Drawing Sun Paths

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khartwell (15 mai 2017)

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7. Drawing Sun Paths¶ 7.1. Drawing Paths of Points¶ Tools4SketchUp offers very different possibilities than the built-in Shadow feature or other plugins available. The first step in your solar analysis should be to set the location of your project, as well as setting the time-period for your analysi...

Creating Isovists

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khartwell (15 mai 2017)

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8. Ray Casting 8.1. Ray Casting : an Introduction to Visibility Studies¶ Ray Casting involves choosing a point in your urban space, from which rays will spread at equal distance from each other. The ray stops when it hits either an obstacle or its set limit. It is the simplest and quickest way to a...

Installation Procedures

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khartwell (10 mai 2017)

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2. Installation Procedures¶ There are multiple ways to install T4SU. Choose the procedure depending on your OS. You can also directly upload it from inside SketchUp. 2.1. Under Windows¶ The following installation procedure assumes that you already have installed a recent release of the SketchUp sof...

Introduction to T4SU

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khartwell (10 mai 2017)

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1. Introduction¶ This Section of MAU is dedicated to T4SU (Tools 4 SketchUp) : You will find walkthroughs and use cases. Depreciated versions of this documentation can also be found on t4su.wordpress.com as well as t4su.readthedocs.io. 1.1. What is t4su ?¶ T4SU (Tools for SketchUp) is a SketchUp plu...