Again, extremely insightful Damian, so thanks! Still struggling a little with the understanding the difference between parametric/generative in the modeling domain...
Looking at this section of your entry: "That thin line, to me, is parametric design being generated by a singular reference to an outside piece of data and generative design being generated by a multitude of references an some interpretation of those references in an interconnected manner" Could you perhaps expand with an example of these 'multitude of references' and the interconnected referencing within a CAD/GH context to help me better understand your point? thanks D On Mar 4, 4:22 pm, damien_alomar <[email protected]> wrote: > Although I more or less agree with that definition my personal view of > Generative Design is slightly different. For lack of a better example > I'm going to go with DNA. In its raw state, DNA contains all of the > instructions by which life can be created. It will dictate the growth > of cells as well as the type/characteristics of cells. Theoretically > you could clone someone from their DNA and get an exact "copy" of that > person (remember Dolly?). However, the end result of that clone would > not be an exact copy. Why? The growth of cells is not dictated solely > by DNA, but also by its interactions with its surroundings. Since the > clone invariably develops in conditions that were different from the > "source being" there will always be a difference between the two. > > To me, this is the characteristic of generative design. Its not just > a product of the parameters that generate it, but of the conditions > that surround and interact with it. Even within that definition, > there's a very thin line that separates parametric design from > generative design, since both rely on defining their operations > through external values. That thin line, to me, is parametric design > being generated by a singular reference to an outside piece of data > and generative design being generated by a multitude of references an > some interpretation of those references in an interconnected manner. > > I've moved towards defining GH as a Logical Modeler rather than > parametric or generative. The main reason is that most parametric > modelers rarely focus on the link between parameters as an artifact of > their process. Because of this, their process, though parametrically > based, is still embedded within model itself, which is certainly > fine. GH does not operate in this manner. The creation of a GH > definition is more of a representation of the logical steps used to > create a given output, where as with parametric modelers, the > representation of the inheritance of all parameters is not nearly as > evident. Considering the control, amount of information that is > immediately available by looking at a definition, and the interaction > with those logical steps I would certainly argue that THAT is an > extremely valuable aspect of the GH process. I could possibly argue > that the GH definition itself is more valuable than the output it > creates. > > As to the Generative capabilities of parametric modelers and GH, it > all depends on how you structure the interactions with external data. > A 1 to 1 relationship between a value and an output is more parametric > in my book, where the interaction between a multitude of values is > more of a generative approach. > > Just my 2 cents > > Best, > Damien > > On Mar 4, 9:51 am, David Rutten <[email protected]> wrote: > > > Wikipedia: > > > "The term "generative modelling" describes a paradigm change in shape > > description, the generalization from objects to operations: A shape is > > described by a sequence of processing steps, rather than just the end > > result of applying these operations. Shape design becomes rule > > design." > > > Well, that's clear enough. I'm still having a hard time drawing a > > sharp line between parametric and generative though. > > > -- > > David Rutten > > [email protected] > > Robert McNeel & Associates > > > On Mar 4, 3:48 pm, David Rutten <[email protected]> wrote: > > > > Hi Daniel, > > > > a parametric modeler is one that's driven by parameters, as > > > disappointing as it sounds. So, yes, on a basic level ALL modelers can > > > be considered parameteric. > > > However, that wouldn't be a useful term since it wouldn't exclude > > > anything, so when we talk about parametric modelers we usually refer > > > to indirect parameters. > > > > For example, in Rhino you define a line segment by specifying the > > > start and end point. This is typically not considered parametric. In > > > Solidworks you can define a line segment as a tangent relationship to > > > a circle and a certain length and angle. This would be considered > > > parametric. One of the major outcomes of this different ideology is > > > that parametric models tend to be history based. When you define new > > > geometry using existing geometry, it doesn't take much to change the > > > starting conditions and have the entire model adjust itself. So, I > > > think most people will agree that in a non-parametric environment you > > > directly design the model, whereas in a parametric environment you > > > design the description of the model. In this light, Grasshopper is > > > definitely parametric. > > > > However, the term "parametric" has been applied to packages such as > > > Solidworks and Catia and Pro-E for so long that it is now tightly > > > associated with that particular style of interface. Perhaps this is > > > why the term "Generative" has been introduced. To be honest, I don't > > > exactly know what generative modeling is supposed to be. > > > > -- > > > David Rutten > > > [email protected] > > > Robert McNeel & Associates > > > > On Mar 4, 11:37 am, daniel hilldrup <[email protected]> > > > wrote: > > > > > Hi All, > > > > > I don't know if I am in the right place to start this debate, but I am > > > > looking for answers > > > > to my questions as I am about to undertake research on the field of > > > > 'parametric' CAD design and am looking for some terminology > > > > definitions. > > > > > I am a MA product design student looking to adopt some of Grasshoppers > > > > excellent > > > > capabilities, and apart from the research would like to know how the > > > > software is defined. > > > > > OK my questions/statement: > > > > > What is a parametric design? Is there a definitive definition? > > > > At a fundamental level isn't all CAD parametric, using parameters that > > > > state type, insertion point and direction (as with a line). Elsewhere > > > > I see, dimension based modelers classified as parametric.... > > > > > Is Grasshopper Parametric? I know that the 'blurb' states that it is a > > > > Generative Modeler > > > > using algorithms, so does it make it parametric? > > > > > Would really appreciate any sources of information on the definitions > > > > of generative/parametric modeling and the differences. > > > > > Right, back to the hopper to see if I can make something from this > > > > incredible software!
