but rather than keep everyone waiting, I've decided to share some as they become ready.
This also has the advantage that questions about components can be more easily grouped under the relevant post - so please do add any questions / comments / bugs / suggestions about these examples below.
So today I am posting some examples of the mesh utilities that come with the new release.
While these are not directly physics based, many of the forces and types of relaxation in Kangaroo are designed to work with meshes, and in the process of development I've ended up adding a number of simple utilities to make working with them a little easier.
I recommend also installing Weaverbird which has many more subdivision functions and other useful tools for working with meshes in Grasshopper. Also Plankton, Turtle, MeshEdit and Starling extend these possibilities still further.
Diagonalize
This component replaces every edge of a mesh with a new face. The new faces will always be quads, except for along the boundaries, where they will be triangles. It can be used to easily create diagrids. The input mesh can contain any mix of triangles and quads.
When treating the edges of a quad mesh as springs, diagonalizing it will often significantly change its physical behaviour. If you are trying to planarize a quad mesh, diagonalizing may sometimes allow you to stay closer to a target shape if it matches the curvature directions better.
diagonalize.gh
Checkerboard
This component assigns the faces of a mesh into a checkerboard pattern. The output is a list of 1s and 0s (which could represent black/white or true/false) which can be used to dispatch the faces into 2 lists, where no pair of adjacent faces have the same colour.
One nice application I found for this is applying alternating clockwise and counter-clockwise rotations as shown below. Also, on occasion you may want to planarize a quad mesh, but have some constraints on the shape and grid that prevent this, and triangulating only alternating quads to give a hybrid quad/tri mesh can sometimes be a good compromise, allowing a bit more freedom.
Note - Not all meshes can be assigned a checkerboard pattern!
As a simple example, take a mesh with 3 quads around one vertex - If we assign one black face, then both the neighbouring faces should be white, but then we have 2 white faces adjacent to one another, which violates the checkerboard condition.
Generally, we can say that if a mesh has any internal vertex with an odd number of faces around it, then we cannot apply a consistent checkerboard pattern to it (although not having any odd valence vertices is not in itself an absolute guarantee that a mesh is 'checkerboardable').
checkerboard.gh
WarpWeft
This sorts the edges of a quad mesh into 2 lists of line segments, which are like the warp and weft directions of a fabric. They can also be seen as a sort of mesh equivalent to the u and v isocurves on a NURBS surface.
This can be useful if you want to control the shape of a tension structure, because it allows you to assign different stiffnesses in the 2 directions.
As with the checkerboard component, not all meshes can be consistently assigned warp/weft directions. It follows a similar rule - all internal vertices should have an even number of adjacent faces. With a bit of care, it is usually possible to model the initial mesh in such a way as to allow this.
This component also has an output telling us whether or not each line is on a boundary of the mesh, as we will often want to treat these differently.
Same mesh relaxed with different warp/weft stiffness:
warpweft.gh
MeshCorners
This one is hopefully fairly self explanatory. In many simulations we want to anchor the corner points of a mesh. This saves us having to pick them manually in Rhino.
It works on quad meshes, and looks around the boundary vertices for any which do not have exactly 3 connected edges.
corners.gh
That's all for now. Coming soon - a "mesh tools 2" post explaining more of the components.…
lly it should not make much of a difference - random number generation is not affected, mutation also is not. crossover is a bit more tricky, I use Simulated Binary Crossover (SBX-20) which was introduced already in 1194:
Deb K., Agrawal R. B.: Simulated Binary Crossover for Continuous Search Space, inIITK/ME/SMD-94027, Convenor, Technical Reports, Indian Institue of Technology, Kanpur, India,November 1994
Abst ract. The success of binary-coded gene t ic algorithms (GA s) inproblems having discrete sear ch sp ace largely depends on the codingused to represent the prob lem variables and on the crossover ope ratorthat propagates buildin g blocks from pare nt strings to childrenst rings . In solving optimization problems having continuous searchspace, binary-co ded GAs discr et ize the search space by using a codingof the problem var iables in binary st rings. However , t he coding of realvaluedvari ables in finit e-length st rings causes a number of difficulties:inability to achieve arbit rary pr ecision in the obtained solution , fixedmapping of problem var iab les, inh eren t Hamming cliff problem associatedwit h binary coding, and processing of Holland 's schemata incont inuous search space. Although a number of real-coded GAs aredevelop ed to solve optimization problems having a cont inuous searchspace, the search powers of these crossover operators are not adequate .In t his paper , t he search power of a crossover operator is defined int erms of the probability of creating an arbitrary child solut ion froma given pair of parent solutions . Motivated by t he success of binarycodedGAs in discret e search space problems , we develop a real-codedcrossover (which we call the simulated binar y crossover , or SBX) operatorwhose search power is similar to that of the single-point crossoverused in binary-coded GAs . Simulation results on a number of realvaluedt est problems of varying difficulty and dimensionality suggestt hat the real-cod ed GAs with t he SBX operator ar e ab le to perform asgood or bet t er than binary-cod ed GAs wit h t he single-po int crossover.SBX is found to be particularly useful in problems having mult ip le optimalsolutions with a narrow global basin an d in prob lems where thelower and upper bo unds of the global optimum are not known a priori.Further , a simulation on a two-var iable blocked function showsthat the real-coded GA with SBX work s as suggested by Goldberg
and in most cases t he performance of real-coded GA with SBX is similarto that of binary GAs with a single-point crossover. Based onth ese encouraging results, this paper suggests a number of extensionsto the present study.
7. ConclusionsIn this paper, a real-coded crossover operator has been develop ed bas ed ont he search characte rist ics of a single-point crossover used in binary -codedGAs. In ord er to define the search power of a crossover operator, a spreadfactor has been introduced as the ratio of the absolute differences of thechildren points to that of the parent points. Thereaft er , the probabilityof creat ing a child point for two given parent points has been derived forthe single-point crossover. Motivat ed by the success of binary-coded GAsin problems wit h discrete sear ch space, a simul ated bin ary crossover (SBX)operator has been develop ed to solve problems having cont inuous searchspace. The SBX operator has search power similar to that of the single-po intcrossover.On a number of t est fun ctions, including De Jong's five te st fun ct ions, ithas been found that real-coded GAs with the SBX operator can overcome anumb er of difficult ies inherent with binary-coded GAs in solving cont inuoussearch space problems-Hamming cliff problem, arbitrary pr ecision problem,and fixed mapped coding problem. In the comparison of real-coded GAs wit ha SBX operator and binary-coded GAs with a single-point crossover ope rat or ,it has been observed that the performance of the former is better than thelatt er on continuous functions and the performance of the former is similarto the lat ter in solving discret e and difficult functions. In comparison withanother real-coded crossover operator (i.e. , BLX-0 .5) suggested elsewhere ,SBX performs better in difficult test functions. It has also been observedthat SBX is particularly useful in problems where the bounds of the optimum
point is not known a priori and wher e there are multi ple optima, of whichone is global.Real-coded GAs wit h t he SBX op erator have also been tried in solvinga two-variab le blocked function (the concept of blocked fun ctions was introducedin [10]). Blocked fun ct ions are difficult for real-coded GAs , becauselocal optimal points block t he progress of search to continue towards t heglobal optimal point . The simulat ion results on t he two-var iable blockedfunction have shown that in most occasions , the sea rch proceeds the way aspr edicted in [10]. Most importantly, it has been observed that the real-codedGAs wit h SBX work similar to that of t he binary-coded GAs wit h single-pointcrossover in overcoming t he barrier of the local peaks and converging to t heglobal bas in. However , it is premature to conclude whether real-coded GAswit h SBX op erator can overcome t he local barriers in higher-dimensionalblocked fun ct ions.These results are encour aging and suggest avenues for further research.Because the SBX ope rat or uses a probability distribut ion for choosing a childpo int , the real-coded GAs wit h SBX are one st ep ahead of the binary-codedGAs in te rms of ach ieving a convergence proof for GAs. With a direct probabilist ic relationship between children and parent points used in t his paper,cues from t he clas sical stochast ic optimization methods can be borrowed toachieve a convergence proof of GAs , or a much closer tie between the classicaloptimization methods and GAs is on t he horizon.
In short, according to the authors my SBX operator using real gene values is as good as older ones specially designed for discrete searches, and better in continuous searches. SBX as far as i know meanwhile is a standard general crossover operator.
But:
- there might be better ones out there i just havent seen yet. please tell me.
- besides tournament selection and mutation, crossover is just one part of the breeding pipeline. also there is the elite management for MOEA which is AT LEAST as important as the breeding itself.
- depending on the problem, there are almost always better specific ways of how to code the mutation and the crossover operators. but octopus is meant to keep it general for the moment - maybe there's a way for an interface to code those things yourself..!?
2) elite size = SPEA-2 archive size, yes. the rate depends on your convergence behaviour i would say. i usually start off with at least half the size of the population, but mostly the same size (as it is hard-coded in the new version, i just realize) is big enough.
4) the non-dominated front is always put into the archive first. if the archive size is exceeded, the least important individual (the significant strategy in SPEA-2) are truncated one by one until the size is reached. if it is smaller, the fittest dominated individuals are put into the elite. the latter happens in the beginning of the run, when the front wasn't discovered well yet.
3) yes it is. this is a custom implementation i figured out myself. however i'm close to have the HypE algorithm working in the new version, which natively has got the possibility to articulate perference relations on sets of solutions.
…
Analysis Tools (LAT). Our plugin has come a long way in the last 4 years and, while the legacy version will still include some small updates and contributions, we are confident in saying that the changes will be far fewer and the plugin more stable in the following months as we switch gears into the LAT effort. I can say personally that (save for a couple of small capabilities) I have made it through my list of critical features and I will hereafter be working on making these features cross-platform, cleanly-implemented, and well-documented in the new Ladybug Analysis Tools software package. As always, you can download the new release from Food4Rhino. Make sure to remove the older version of Ladybug and Honeybee and update your scripts.
The majority of changes with this release represent “icing on the cake” after a long, multi-year effort to connect to the major open source engines and datasets. So, without further adieu, here is the list of the new capabilities added with this release:
LADYBUG
Stereographic Sky Projections - Thanks to several code contributions from Byron Mardas, all Ladybug sky visualizations now support stereographic projections! Such projections are useful for understanding the hemispherical visualizations in a 2D format and they also make it easier to overlay different sky datasets on top of one another. Check here for an example file showing the sun path overlaid with helpful/harmful parts of the sky and see here for an example file using shading masks representing strategies (like an overhang) on top of the helpful / harmful portions of the sun path.
Wind Rose Upgrades - Devang Chauhan has added several new features to the Ladybug wind rose including both visual and numerical outputs of average wind velocity and frequency for each petal of the rose. Not only does this enhance the usefulness of the rose but it also paves the way for the use of the wind rose to set up CFD simulations once Butterfly is released in the near future. The new features of the wind rose can be seen in this hydra example file.
Complete Set of Local Thermal Discomfort Models - After the last release included components to evaluate radiant asymmetry discomfort (which can be modeled using these example files: 1, 2), today’s release completes Ladybug’s suite of local discomfort models from ASHRAE and the ISO by adding components to account for discomfort from cold draft. Specifically, two draft models have been added for different types of situations. The first is an older model published by P.O. Fanger, which was developed through experiments where subjects had cold air blown on the back of their neck (the most sensitive part of the body to draft). While this is useful for understanding a worst-case scenario, it can greatly overestimate the discomfort for cases of draft at ankle level - a more common occurrence that typically results from the tendency of cold air to sink. For this situation, a second draft discomfort model has been included, which is specifically meant to forecast ankle draft discomfort. The model is currently undergoing review for integration into ASHRAE-55 and a publication outlining the derivation of this model can be found here:
Liu, S., Schiavon, S., Kabanshi, A. and Nazaroff, W. (2016), Predicted Percentage Dissatisfied with Ankle Draft. Indoor Air. Accepted Author Manuscript. doi:10.1111/ina.12364 (http://escholarship.org/uc/item/9076254n).
Special thanks is due to Shichao Liu, Toby Cheung and Stefano Schiavon for sharing the model and the results of their study with the development team. The integration of draft models completes the full integration of ASHRAE-55 and EN-15251 with Ladybug. Now, you can rest assured that, if there is a certain thermal comfort standard that you need to fulfill for a given project, you can model it with the ‘bug!
Window-Based Draft Model - With the integration of draft models, the first question that one might ask is “how should these models be applied to typical design cases?” While the (soon-to-be-released) Butterfly plugin for OpenFOAM should open up a Pandora’s box of possible situations, this release of Ladybug includes a simplified downdraft model from cold vertical surfaces, which helps model several typical cases of draft discomfort. The model has been validated across several papers:
Heiselberg, P. (1994). Draught Risk From Cold Vertical Surfaces. Building and Environment, Vol 29, No. 3, 297-301
Manz, H. and Frank, T. (2003). Analysis of Thermal Comfort near Cold Vertical Surfaces by Means of Computational Fluid Dynamics. Indoor Built Environment. 13: 233-242
It has been built into the “Ladybug_Downdraft Velocity” component and has been included in an example file illustrating discomfort from cold windows in winter. The example is intended to show when glazing ratio and window U-Values are small enough to eliminate perimeter heating - a practice that is aesthetically unpleasing, costly to maintain and wasteful in its energy use.
Operative Temperature on the Psychrometric Chart - This is a feature that should have been added a long time ago but we are finally happy to say that the Ladybug_Psychrometric Chart can draw a comfort polygon assuming that the air temperature and radiant temperature are the same value (aka. an operative temperature psychrometric chart). This operative temperature chart is the format that is needed to use the ASHRAE-55 graphical method and is generally a better representation of the range of comfort in cases where one does not intend to hold the radiant temperature constant. This operative temperature capability is now set as the default on the component but you can, of course, still bring back the older comfort polygon by simply plugging in a value for meanRadiantTemperature_.
Contour Map Visualizations - Using the same inputs as the Ladybug_Recolor Mesh component, the new Ladybug_Contour Mesh component allows you to generate contoured color graphics from the results of any analysis. Now, you to maximize the use of your high-resolution studies with contours that highlight thresholds and gradients!
Image Texture Mapping for Colored Meshes - Antonello DiNunzio has added the very useful Ladybug_Texture Maker component, which allows you to bake Ladybug colored meshes with image texture maps (as opposed to the classic method that used colored vertices). This enables the creation of transparent Ladybug meshes, making it even easier to overlay Ladybug graphics with one another and with Rhino geometry:
This component also adds the ability to render Ladybug + Honeybee meshes with other rendering programs like V-Ray and 3ds Max. So you can produce Ladybug graphics like this!
Finally, image-mapped textures are also the format required for gaming and Virtual Reality software like Unity and Augmented Reality programs like Augment. So now you can export your Ladybug meshes all of the way to the virtual world!
Rhino Sun Component - If you have ever had to set up the sun for a rendering plugin and wished that you could just take your Ladybug sun and use that, then you are in luck! Byron Mardas has contributed a component that lets you set the Rhino sun based on your EPW location data, your north direction (if different from the Y-Axis) and any time of day that you want. Not only does this make it easier to coordinate the Rhino sun with your Ladybug visualizations, but you can also use it for real time shadow previews by setting your Rhino view to “Rendered” and scrolling through a slider.
Rendered Ladybug Animations - With both the image texture mapping and the Rhino sun components released, your first thought might be “it would be great if I could use this all in a rendered animation!” Thankfully, Ladybug has added a new component to help you here. The Ladybug_Render View component works in essentially the same way as the Capture View component, allowing you to make a series of images as you animate through a slider. The major benefit here is that it works with both Rhino Render and V-Ray so that animations like this can be produced effortlessly:
Cone of Vision Added - Antonello Di Nunzio has added a component that allows you to visualize various cones of vision in order to help inform your view studies. You can fine tune parameters to include just text-readable or full peripheral vision and use the resulting view cone to constrict the results of your “Ladybug_View Analysis” studies.
Terrain WIP Components Released as the Gismo Plugin - Our friend Djordje has released a new plugin Gismo - a plugin for GIS environmental analysis. As a result the following 5 terrain components: Horizon Angles, Flow Paths, Terrain Shading Mask, Terrain Generator 2, Terrain Analysis, have been removed from Ladybug+Honeybee's WIP section and are added to Gismo.
HONEYBEE
Search, Select, and Import the Hundreds Outputs from EnergyPlus/OpenStudio - Many of the power users in our community know that EnergyPlus is capable of writing several hundred different outputs from the simulation (well beyond what the basic Honeybee result readers can import). While Honeybee has always allowed one to request these outputs by adding them to the simulationOutputs_ of the component, there has not been an official workflow for searching through all of the possible outputs or importing their specific results… until now! We have added the "Honeybee_Read Result Dictionary" component, which allows you to parse the Result Data Dictionary (or .rrd file) that EnergyPlus outputs during every run of a given model. This allows you to see all of the outputs that are available for the model and you can even search through this list to find a particular output that you are interested in. Once you find what you are looking for, simply copy the text output from the component into a panel and and plug this into simulationOutputs_. Then you can use the "Honeybee_Read EP Custom Result" component to bring your custom results into GH after rerunning the simulation. The example file of an evaporative cooling tower shows how to use the workflow to request and import in the energy removed by the tower.
OpenStudio HVAC System Sizing Results - After the full integration of HVAC in the last release, we realized that a number of people wanted to run EnergyPlus models simply to evaluate the size of the Heating/Cooling system in the model (obtained from the EnergyPlus autosize calculation that is run at the start of every simulation). Such a sizing calculation can be a great way to quantify the anticipated savings from a given strategy (like shading) on the size/cost of the building’s HVAC system. To get the results of the sizing calculation, all that one needs to do is connect the output eioFile from the OpenStudio component to the Honeybee_Read HVAC Sizing component. The outputs will indicate the peak heating/cooling loads of each zone (in Watts) as well as the size of each piece of HVAC equipment in the model. The next time that you are on a project that is about to value-engineer out an exterior shading system, use the workflow in the following example file to show that the client will probably end up paying for it with a more expensive HVAC system: Quantifying HVAC Sizing Impact of Shade.
Improved Memory Usage When Building Large Energy Models - As we take the capabilities of Honeybee to larger and larger models, many of us have begun to run up against a particular limitation of our machines: memory. After upgrading our machines to have 32 GBs of RAM, there was only one way left to alleviate the problem: restructure some of the code. Honeybee now uses an enhanced approach that ensures all the previous iterations of Honeybee objects will be removed from the memory once there is a change. In any case, the considerations of memory are definitely something that we intend to improve with the future Honeybee[+] plugin.
Workflow to Import gbXML Files - While GrizzlyBear has been around for several years, enabling us to export Honeybee zones to gbXML, we have gone for quite some time without a workflow to import gbXML files to Honeybee. The new Honeybee_gbXML to Honeybee component addresses this and establishes an easier path to import models from Revit into honeybee. You can read more about the component in this post.
Window Frame Capabilities Added to OpenStudio - After the implementation of LBNL THERM / WINDOW capabilities in the last two releases, there was one final bridge to build in the Honeybee workflow - fully connecting LBNL WINDOW to Honeybee’s OpenStudio workflow. This release of Honeybee will now write all FrameAndDivider objects exported from LBNL WINDOW glazing systems into the energy simulation, enabling you to account for the frame’s thermal bridging effects. As long as the construction is brought in with the Honeybee_Import WINDOW IDF Report component, the frames associated with the construction will be assigned to all windows that have the construction. Finally, it is worth noting that the current Honeybee will also write all glass spectral data as well as gas (or gas mixture) materials into the simulation. This means that essentially all properties of any IDF export that one makes from LBNL WINDOW can be factored into the OpenStudio energy simulation (with the only exception being BSDF materials).
OpenStudio Daylight Sensors Added - In our previous releases of Honeybee, the only means of correctly account for daylight sensors in an energy simulation was to run an annual daylight simulation and use the resulting schedules for the lighting in the energy simulation. However, this can take a lot of time and work to set up and run, particularly if the daylight control (at the end of the day) will be driven by just one sensor per room. Now, we have added another option, which uses OpenStudio/EnergyPlus’s built-in daylight controls. You can assign just a point and an illuminance target on the “Set Zone Thresholds” component and the lighting will be automatically adjusted in the course of the simulation. It should also be noted that the addition of daylight sensors has also coincided with the addition of blind/shade control based on glare. The same sensor point for daylight can be used to drive dynamic shades in the energy simulation based on glare experienced at this point. This example file shows how to set up daylight controls on the EnergyPlus model and check the lighting power results to see the effect.
Better Defaults for Natural Ventilation - After many good people wrote to me informing me that Honeybee overestimates natural ventilation airflow and I wrote back showing the way that I intended natural ventilation to be set up with the component, it dawned on me that I had selected some poor component defaults. Accordingly, this release includes a window-based natural ventilation option on the Set EP Airflow component that corrects for some of the common issues that I have seen. Insect screens are included by default and the component runs a general check to see if wind-driven cross ventilation is possible before auto-assigning it. The component will air on the side of more-conservative, lower airflow rates unless the user overrides the defaults. Finally, it’s worth noting that all of these changes have not affected the freedom of the Custom WindAndStack option on the component. The new defaults can be viewed in this example file.
CFD Results Can be Plugged into Microclimate Maps - In preparation for the (very soon) release of the Butterfly that connects to the OpenFOAM CFD platform, we just wanted to note that all of the microclimate map recipes can now take an input of a csv file with a matrix of CFD results for wind speed. For the time being, we have used these to produce very high-accuracy, high resolution maps of outdoor comfort. There will be more to follow soon!
We should also note that, in the last release I mentioned that we would be phasing out the EnergyPlus component so that all efforts are focused on the OpenStudio component. While I reiterate that all of the features of the EnergyPlus component are available in the OpenStudio component and I encourage everyone to use the OpenStudio component in order to take advantage of its HVAC capabilities, I have come to realize that many prefer to use the EnergyPlus component out of habit and have not yet gotten the time to understand why the OpenStudio component is an improvement over the EnergyPlus component. As a result, we have decided to leave the EnergyPlus component in place for the time being so that everyone has more time to understand this. The future Ladybug Analysis Tools platform will only interact with EnergyPlus through OpenStudio and so it is recommended that everyone use these two components in the Honeybee plugin will serve as an educational resource to understand our current path moving forward with OpenStudio.
Lastly, it is with great pleasure that we welcome Devang Chauhan and Byron Mardas to the developer team! As mentioned previously Devang has contributed several updates to the Ladybug Wind Rose in addition to finding and solving a multitude of bugs in other components. Byron has contributed code that has enabled the previously-mentioned stereographic sky projections along with a better method for running the Ladybug Sky Mask. Finally, Byron has contributed the Rhino Sun component, which allows you to coordinate your Rhino renders with your Ladybug data. Welcome to the Ladybug team, gentlemen!
As always let us know your comments and suggestions. Cheers!
Ladybug Analysis Tools Development Team…
guages I'd recommend all use the RhinoCommon SDK and thus all have access to the same functionality.
How long would it take me to understand and write my own code?
If you already know how to program, it probably won't take too long. If you're past the hurdle of what it means to declare and assign variables, how conditionals and loops work and what scope is, you've already rounded the hardest corner.
Is it even worth it?
That really depends. "Learn programming" is clearly not blanket good advice. Most people out there do not have to learn programming to be happy with their lives and successful in their careers. For some people it can make a small difference, and for a few people it can make a huge difference. If you feel you're in the 'some' category then this is indeed a question you have to answer. Note that the investment for learning programming is a continuous process. Unless you keep up your skills and learn about new stuff that becomes available, you'll lose the ability to write successful code over time.
Where do I start?
Step 1 is to answer the previous question. It is unlikely that anyone besides yourself can answer it, but you can start by making a list of things you do manually now that may be programmable. Then make a list of the things you are unable to do now but which you might be able to do with programming. If while looking at these lists your reaction is: "meh", the answer is probably no.
Step 2 is to pick a language. This is again a very personal thing; there's no wrong answer, because there's no right answer.
Step 3 is to start learning this language. My experience is that the best way to learn a programming language is to try and solve a real problem that you understand very well. If the problem statement is nebulous or poorly understood, you'll be learning two things and that's a recipe for unnecessary frustration.
Here are my thoughts on language:
Python: I don't use Python myself, I can sort of read it while moving my lips. I don't particularly like Python though. The indentation sensitiveness stresses me out, and I find the lack of type-safety disturbing. However it is a good language for mathematical/scientific programs. There are lots of additional code libraries you can easily import that will ease the development of mathematically intense algorithms.
C#: I like C# very much, but it does suffer from geekerosis. A lot of the keywords used in the language are not self-explanatory (abstract, sealed, virtual). For me this is no longer a problem as I've memorised what they all mean. C# is designed to be an efficient language to write, rather than an easy one to learn.
The great thing about C# though is that there's a huge amount of material out there for learning it. It is one of the most popular, mature and modern languages you can hope to pick.
VB: I learned VBScript as my first language, and then moved on to VB5, VB6 and VB.NET. It is somewhat more friendly than C#, and functionally it is almost identical. The switch from VB to C# is reasonably low-threshold and there are excellent tools for translating VB code to C# and vice versa.
Since you already know some Python, it probably makes the most sense to continue on that path. If you want to switch, C# is more like Python than VB, so C# would be my next suggestion.
As for where to get information... you have 4 major options when developing code for Rhino.
If it's a question about the language itself, StackOverflow is a great resource. It can be a pretty hostile place for beginner questions, but I find that mostly the questions I'm asking have been asked already and the answers on SO tend to be good. In fact usually when I google my questions, the first few hits are always SO posts.
If it's a question about the Rhino SDK or Grasshopper, you can ask it either on the GH forums (where we are now), or on Discourse. We're not as quick on the draw as SO, but we do know about Rhino.
If you're looking for a basic explanation of what a keyword or a type is for, perhaps with an example, MSDN is the best first choice. In fact if you google the name a of a .NET type, the first hit is almost always an MSDN page.…
Added by David Rutten at 2:03pm on December 3, 2014
umbrella of Urban Heat Island (UHI) and I am going to try to separate them out in order to give you a sense of the current capabilities in LB+HB.
1) UHI as defined as a recorded elevated air temperature in an urban area:
If you have access to epw files for both an urban area and a rural area, you can use Ladybug to visualize and deeply explore the differences between the two weather files. Ladybug is primarily a tool for weather file visualization and analysis and it can be very helpful for understanding the consequences of UHI on strategies for buildings or on comfort. This said, if you do not have both rural and urban recorded weather data or you want to generate your own weather files based on criteria about urban areas (as it sounds like you want to do), this definition might not be so helpful.
2) UHI defined by air elevated air temperature but viewed as a computer model-able phenomenon resulting primarily from urban canyon geometry, building materials, and (to a lesser degree) anthropogenic heat:
This definition seems to fit more with they type of thing that you are looking for but it is unfortunately very difficult and computationally intensive such that we do not currently have anything within Ladybug to do this right now. I can say that the state-of-the art for this type of modeling is an application called Town Energy Budget (TEB) and this is what all of the advanced UHI researches that I know use (http://www.cnrm.meteo.fr/surfex/spip.php?article7). Unfortunately for those trying to use it in professional practice, it can take a while to get comfortable with it and it currently runs exclusively on Linux (this does mean that it is open source, though, and that you can really get deep into the assumptions of the model). A couple years ago, a peer of mine translated almost all of TEB into Matlab language making it possible to run it on Windows if you have Matlab. He wrapped everything together into a tool called the Urban Weather Generator (UWG), which can take an epw file of a rural area and warp it to an urban area based on inputs that you give of building height, materials, vegetation, anthropogenic heat, etc. I would recommend looking into this for your project, although, bear in mind that is it not open source like the original TEB tool and that you may need to get a (very expensive) copy of MATLAB (http://urbanmicroclimate.scripts.mit.edu/uwg.php).
3) UHI as defined by a thermal satellite image of an urban area depicting an elevated average radiant environment that reaches a maximum a the city center and changes by land use:
This is the definition of UHI that I am most familiar with and was the basis of much of my past research. I feel that it is also a definition of UHI that is a bit more in line with where a lot of contemporary UHI research is headed, which is away from the notion of UHI as a macro-scale meteorological phenomena that is averaged as an air temperature over a huge area towards one that accepts that different land uses have different microclimates and (importantly) different radiant environments. While the air temperature difference between urban and rural areas usually does not change more than 1-4 C, the radiant environment can be very different (on the order of 10-15 C differences). The best way to understand UHI in this context is with Thermal satellite images, for which there is ha huge database of publicly available data on NASA's glovis website (http://glovis.usgs.gov/) or their ECHO website (http://reverb.echo.nasa.gov/reverb/#utf8=%E2%9C%93&spatial_map=satellite&spatial_type=rectangle). I tend to use thermal data from LANDSAT 5-8 and ASTER satellites in my research. Unfortunately, there is a lot f bad data with a lot of cloud cover mixed in with the really good stuff and it can take some time to find good images. Also, there aren't too many programs that read the GeoTiff file format that you download the data as. I know that ArcGIS will read it, a program called ENVI will read it (I think that the open source QGIS can also red it). I have plans to write a set of components to bring this type of data into Rhino and GH (I may get to it a few months down the line).
4) UHI as a computer model-able notion of "Urban Microclimate" with consideration of local differences and the local radiant environment:
This is where a lot of my research has lead and, thankfully, is an area that Honeybee can help you out a lot with. EnergyPlus simulations can output information on outside building surface temperatures and these can be very helpful in helping get a sense of the radiant environment around individual buildings. Right now, I am focusing just on using this data to fully model the indoor environments of buildings as you see in this video:
https://www.youtube.com/watch?v=fNylb42FPIc&list=UUc6HWbF4UtdKdjbZ2tvwiCQ
I have plans to move this methodology to the outdoors once I complete this initial application to the indoors. For now, you can use the "Surface result reader" and the "color surfaces based on EP result" components to get a sense of variation in the outside temperature of your buildings.
I hope that this helped,
-Chris
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ther math and logic. i can usually conceptualise what i want to do and cobble some semi working thing together but don't know which components to use and how to patch it. so i'm super happy to have someone who knows what he's doing to find this interesting.
and i'm glad you mention the fanned frets again, there is one input parameter that's still missing for the multiscale frets to be fully parametric, it's the angle of the nut or which fret should be straight. it depends a bit on personal preferences and playing posture what is more comfortable. so being able to adjust this easily would be cool. again i have no idea how the maths for that work or if you can just rotate each fret the same amount around it's middle point. The input either as fret number (for the straight fret) or as a simple slider from bridge to nut should do as input setting.
Here are the two extremes and the middle ground:
i've been thinkin today while analysing your patches and cleaning up my mess what exactly the monster should do.
Here are the input parameters needed, i think it's the complete list
scale length low E string
scale length high e string
fret angle/straight fret
string width at nut
string width at bridge
number of frets
fretboard overhang at nut (distance from string to fretboard bounds)
fretboard overhang at last fret
string gauges
string tensions
fretboard radius at nut (for compound radius fretboard radius at bridge is calculated with the stewmac formula)
fretwire crown width
fretwire crown height
action height at nut (distance between bottom of string and fretwire crown top)
action height at last fret
pickup 1 neck position
pickup 2 middle position
pickup 3 bridge position
nut width
the pickup positions should be used to draw circles for the magnet poles on each string so they are perfectly aligned and can be used for the pickup flatwork construction. ideally they would need a rotation control aligning the center line of the pickup so it's somewher between the last fret angle and bridge angle. personally i do this visually depending on the design i'm looking for, some people have huge theories on pickup positioning but personally i don't believe in it.
that should result in everything needed to quickly generate all the necessary construction curves or geometry for nut/fingerboard/frets/pickups. this is the core of what makes a guitar work, the more precise this dynamic system is the better the guitar plays and sounds.
i posted another thread trying to understand how i could use datasets form spreadsheets,databse, csv to organize the input parameters. What would make sense for the strings for example is hook into a spreadsheet with the different string sets, i attached one for the d'Addario NYXL string line which basically covers all combos that make sense.
The string tension is an interesting one, and implmenting it would sure be overkill albeit super interesting to try. it should be possible to extrapolate from the scale length of each string what the tension for a given string gauge of that string would be so that you could say 'i want a fully balanced set' or 'heavy top light bottom) and it would calculate which SKU from d'addario would best match the required tension. All the strings listed in the spreadsheet are available as single strings to buy.
i'm trying to reorganize everything which helps me understand it. i just discovered the 'hidden wires' feature which is great since once i understood what a certain block does or have finished one of my own, i can get the wires out of the way to carry on undistracted. a bit risky to hide so many wires but it makes it so much easier not to get completely lost :-)
btw, the 'fanned fret' term is trademarked, some guy tried to patent it in the 80's which is a bit silly since it has been done for centuries. there is a level of sophistication above this as well, check out http://www.truetemperament.com/ and that really is something else. it really is astounding how superior the tuning is on those wigglefrets, the problem is that it's rather awkward for string bending and also you can't easily recrown or level the frets when they are used. …
rmation?" I know that this can already be accomplished using the brilliant Kangaroo plugin, but I wanted a simpler and faster (yet still accurate) single component that could replicate this unique curve using a variety of inputs: the length of the rod/wire, the width/distance between the endpoints, the height of the bend, and the tangent angle at the start. I also wanted make the unknowns (such as height if only length and width are known) easily accessible for plugging into additional components.
The resulting script, being an all-in-one solution, is somewhat unwieldy, but it could easily be broken down into smaller components (custom .gha's which I don't have the ability to code). If someone wants to tackle this, please do! I'm not an expert coder by any means, and as this was only my second time diving into Grasshopper scripting, if the script seems somewhat strange, that's probably why. I did try to comment the code pretty well though. Here's the full description:
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DESCRIPTION: This beast creates the so-called 'elastica curve', the shape a long, thin rod or wire makes when it is bent elastically (i.e. not permanently). In this case, force is assumed to only be applied horizontally (which would be in line with the rod at rest) and both ends are assumed to be pinned or hinged meaning they are free to rotate (as opposed to clamped, when the end tangent angle is fixed, usually horizontally). An interesting finding is that it doesn't matter what the material or cross-sectional area is, as long as they're uniform along the entire length. Everything makes the same shape when bent as long as it doesn't cross the threshold from elastic to plastic (permanent) deformation (I don't bother to find that limit here, but can be found if the yield stress for a material is known).
Key to the formulas used in this script are elliptic integrals, specifically K(m), the complete elliptic integral of the first kind, and E(m), the complete elliptic integral of the second kind. There was a lot of confusion over the 'm' and 'k' parameters for these functions, as some people use them interchangeably, but they are not the same. m = k^2 (thus k = Sqrt(m)). I try to use the 'm' parameter exclusively to avoid this confusion. Note that there is a unique 'm' parameter for every configuration/shape of the elastica curve.
This script tries to find that unique 'm' parameter based on the inputs. The algorithm starts with a test version of m, evaluates an expression, say 2*E(m)/K(m)-1, then compares the result to what it should be (in this case, a known width/length ratio). Iterate until the correct m is found. Once we have m, we can then calculate all of the other unknowns, then find points that lie on that curve, then interpolate those points for the actual curve. You can also use Wolfram|Alpha as I did to find the m parameter based on the equations in this script (example here: http://tiny.cc/t4tpbx for when say width=45.2 and length=67.1).
Other notes:
* This script works with negative values for width, which will creat a self-intersecting curve (as it should). The curvature of the elastica starts to break down around m=0.95 (~154°), but this script will continue to work until M_MAX, m=0.993 (~169°). If you wish to ignore self-intersecting curves, set ignoreSelfIntersecting to True
* When the only known values are length and height, it is actually possible for certain ratios of height to length to have two valid m values (thus 2 possible widths and angles). This script will return them both.
* Only the first two valid parameters (of the required ones) will be used, meaning if all four are connected (length, width or a PtB, height, and angle), this script will only use length and width (or a PtB).
* Depending on the magnitude of your inputs (say if they're really small, like if length < 10), you might have to increase the constant ROUNDTO at the bottom
REFERENCES: {1} "The elastic rod" by M.E. Pacheco Q. & E. Pina, http://www.scielo.org.mx/pdf/rmfe/v53n2/v53n2a8.pdf {2} "An experiment in nonlinear beam theory" by A. Valiente, http://www.deepdyve.com/lp/doc/I3lwnxdfGz {3} "Snap buckling, writhing and Loop formation In twisted rods" by V.G.A. GOSS, http://myweb.lsbu.ac.uk/~gossga/thesisFinal.pdf {4} "Theory of Elastic Stability" by Stephen Timoshenko, http://www.scribd.com/doc/50402462/Timoshenko-Theory-of-Elastic-Stability (start on p. 76)
INPUT: PtA - First anchor point (required) PtB - Second anchor point (optional, though 2 out of the 4--length, width, height, angle--need to be specified) [note that PtB can be the same as PtA (meaning width would be zero)] [also note that if a different width is additionally specified that's not equal to the distance between PtA and PtB, then the end point will not equal PtB anymore] Pln - Plane of the bent rod/wire, which bends up in the +y direction. The line between PtA and PtB (if specified) must be parallel to the x-axis of this plane
** 2 of the following 4 need to be specified ** Len - Length of the rod/wire, which needs to be > 0 Wid - Width between the endpoints of the curve [note: if PtB is specified in addition, and distance between PtA and PtB <> width, the end point will be relocated Ht - Height of the bent rod/wire (when negative, curve will bend downward, relative to the input plane, instead) Ang - Inner departure angle or tangent angle (in radians) at the ends of the bent rod/wire. Set up so as width approaches length (thus height approaches zero), angle approaches zero
* Following variables only needed for optional calculating of bending force, not for shape of curve. E - Young's modulus (modulus of elasticity) in GPa (=N/m^2) (material-specific. for example, 7075 aluminum is roughly 71.7 GPa) I - Second moment of area (or area moment of inertia) in m^4 (cross-section-specific. for example, a hollow rod would have I = pi * (outer_diameter^4 - inner_diameter^4) / 32 Note: E*I is also known as flexural rigidity or bending stiffness
OUTPUT: out - only for debugging messages Pts - the list of points that approximate the shape of the elastica Crv - the 3rd-degree curve interpolated from those points (with accurate start & end tangents) L - the length of the rod/wire W - the distance (width) between the endpoints of the rod/wire H - the height of the bent rod/wire A - the tangent angle at the (start) end of the rod/wire F - the force needed to hold the rod/wire in a specific shape (based on the material properties & cross-section) **be sure your units for 'I' match your units for the rest of your inputs (length, width, etc.). Also note that the critical buckling load (force) that makes the rod/wire start to bend can be found at height=0
THANKS TO: Mårten Nettelbladt (thegeometryofbending.blogspot.com) Daniel Piker (Kangaroo plugin) David Rutten (Grasshopper guru) Euler & Bernoulli (the O.G.'s)
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Edit: More on the math behind this here.
Cheers,
Will
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Added by Will McElwain at 4:08pm on February 26, 2014