<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"></head><body ><div>Datastructure behaves exactly like C language, if all variables and functions are already writen on a paper or with merise or UML, like it would usually be done with a c or c++ program, variable naming and memory allocation becomes easier. In C this is exactly the same method for accessing a place in memory, traversing a template, from pointer to another, if you want to access directly a particular place in memory, use arrays instead. It's possible to change scalars with textfile like I suggested in my first message in this topic.</div><div><br></div><div><br></div><div><br></div><div><br></div><div><div style="font-size:100%">Patrice Colet </div></div> <br><br><br>-------- Message d'origine --------<br>De : Roman Haefeli <reduzent@gmail.com> <br>Date : 28/05/2013 9:57 (GMT+00:00) <br>A : pd-list <pd-list@iem.at> <br>Objet : Re: [PD] first exercise with data structures <br> <br><br>Thanks for sharing your mind on the topic.<br><br>Probably this has already been covered as a limitation and may I haven't<br>really understood it. There is one thing troubling me at the moment.<br>From what I can see, you can easily get data out of your data structure.<br>And for what I am trying, editing data manually/per GUI is quite easy.<br>But how to set data programmatically, i.e. by message? As you can only<br>change a certain scalar by setting a pointer to it, the only way I see<br>is to traverse all scalars until you find the one you want to change. Is<br>this currently the only way to change a property of a particular scalar?<br><br>Roman<br><br><br>On Sam, 2013-05-25 at 12:13 +0200, João Pais wrote:<br>> jonathan already gave a smart reply to your question, using variable <br>> variables as delimiters in your polygons, you can vary everything. If you <br>> notice, in your first example you could vary the position of the <br>> individual array elements (because you don't have a fixed x distance), but <br>> you couldn't vary the position of the whole array - which wasn't necessary <br>> for now, but I just wanted to remark that.<br>> <br>> I would add only something to your [setsize bar_struct bar_array] <br>> construct: in case you want to get a pointer of a specific template, use <br>> the template's name as argument e.g. [pointer bar_struct], and route the <br>> exit of the 2nd outlet to a [next(. That creates a loop that only stops <br>> when you get your pointer. if you have several scalars of the same <br>> template, adding a [get ...] to that loop makes it better (in case you <br>> have a sort of identifier for each scalar).<br>> <br>> A not-so-efficient-as-Jonathan's example of dynamic polygons can be seen <br>> in my [jmmmp/bezier] abstraction (attached also the upcoming audio <br>> version). Inside my folder are a couple other abstractions using data <br>> structures (some new ones might appear only in the next pd-ext release).<br>> <br>> I wouldn't say "don't bother with data structures", but rather "work a lot <br>> with it and make pressure so that they get improved". besides Jonathan's <br>> remarks, there are many other simple things that make life harder: lack of <br>> methods for simple operations (select previous pointer, or previous/next X <br>> pointers), math or expr functions inside of data-s templates (you need to <br>> get the data and then set it again), can't delete scalars without using <br>> the delete key or clearing the whole canvas, ...<br>> many small things that make one patch a lot just to make simple operations.<br>> and the biggest problem, rendering. don't even try to think of using <br>> data-s for any high-rate GUI. for that better to look at GEM.<br>> <br>> looking at Miller's words, data structures was one of the main reasons to <br>> start Pd. after all this time, they didn't change that much.<br>> <br>> very nice would be to have Ircam's FTM library implemented in Pd, but it <br>> seems to be an impossible task, someone has tried already.<br>> <br>> <br>> > On Fre, 2013-05-24 at 16:13 -0700, Jonathan Wilkes wrote:<br>> >> Here's a quickly made approach that uses quanta syntax and checks<br>> >> for mouse manipulations from the outlet of [struct].<br>> ><br>> > Thanks a lot. A lot of new stuff (for me) in your example.<br>> ><br>> >> I wouldn't recommend spending too much time learning data structures.<br>> >> They are _extremely_ limited with the current implementation.<br>> ><br>> > I appreciate your advice. I have the impression one finds out about the<br>> > limitations only by diving into data structures a bit more deeply.<br>> > Although I haven't a clear picture yet what is possible and what is not,<br>> > I find some of the examples in Millers documentation quite intriguing.<br>> ><br>> > Roman<br>> ><br>> ><br>> >> ----- Original Message -----<br>> >> From: Roman Haefeli <reduzent@gmail.com><br>> >> To: pd-list <pd-list@iem.at><br>> >> Cc:<br>> >> Sent: Friday, May 24, 2013 6:15 PM<br>> >> Subject: [PD] first exercise with data structures<br>> >><br>> >> Hi all<br>> >><br>> >> Finally an attempt to dive into data structures. I read Frank<br>> >> Barknecht's still excellent DS tutorial and, of course, section 4 of<br>> >> Pd's help written by Miller Puckette, which is a bit more demanding, but<br>> >> definitely very interesting. Though I can somewhat follow the simpler<br>> >> example patches, the fundamental concepts are still a bit nebulous.<br>> >><br>> >> Here's my problem. I found how to use [filledpolygon] to draw a<br>> >> rectangle whose width can be changed by mouse interaction. When using<br>> >> the same [struct] as the element of an array, I can draw many rectangles<br>> >> which can be grabbed and moved by the mouse (x-y-array). However, when<br>> >> it is used as an element, the ability to change the width dynamically<br>> >> with the mouse is lost. When it is not part of an array, it cannot be<br>> >> moved easily (without going into edit mode). How can I have both at the<br>> >> same time? Is it even possible at all?<br>> >><br>> >> Attached is an example that illustrates both cases.<br>> >><br>> >> Roman<br>> >><br>> >> _______________________________________________<br>> >> Pd-list@iem.at mailing list<br>> >> UNSUBSCRIBE and account-management -> <br>> >> http://lists.puredata.info/listinfo/pd-list<br>> ><br>> ><br>> ><br>> > _______________________________________________<br>> > Pd-list@iem.at mailing list<br>> > UNSUBSCRIBE and account-management -> <br>> > http://lists.puredata.info/listinfo/pd-list<br>> <br>> <br><br><br><br>_______________________________________________<br>Pd-list@iem.at mailing list<br>UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list<br></body>