23 Replies Latest reply on Apr 15, 2009 12:47 PM by Adolfo Rozenfeld

    Particle Playground in RAM preview

    Level 1
      Using AE CS3 I've built a sequence involving the explosion effect of Particle Playground. I adjusted the Velocity Dispersion parameter to get a good expansion rate for the particles, using RAM preview at 50 percent resolutiion as a test bed. To my surprise, when I rendered the project, the particles flew at many time the rate seen in RAM preview. Any ideas as to why this happened or how to get the RAM preview to faithfully reflect the real render?
        • 1. Re: Particle Playground in RAM preview
          Mylenium Most Valuable Participant
          Never preview at half res, I suppose. ;-) The issue you are probably facing is, that when doing such stuff at half res, you effectively make the plug-in work on a quarter of the pixels (assuming you refer to the layer exploder) which can look drastically different. likewise, sampling of layer maps will be based on the reduced resolution, resulting in different values. I really do think only full res previews will ever give a proper, predictable result.

          Mylenium
          • 2. Re: Particle Playground in RAM preview
            craulmedia Level 1
            tough, not having the ability working at half res with correct preview is a thing that has to be considered from the developers very well.
            most effects are impossible to render-preview in full, impossible!
            • 3. Re: Particle Playground in RAM preview
              Level 1
              I did some experimentation which confirms Mylenium's analysis. I am using layer exploder with subsequent particle behavior determined by the Velocity Dispersion and some interparticle Repel. Both the Velocity Dispersion and the Repel Force Radius are dimensioned in pixels, so when you lower resolution, pixels get bigger as a fractiion of screen size and the effects change. Dispersion Velocity is faster and the Repel force extends over a wider range giving even more dispersal. I have enough RAM that I can preview the critical frames at full-res. But Thomas is right, AE should be fixed so that when previewing at lower res effects with parameters dimensioned in pixels are adjusted so their effect is the same as measured in fractions of screen width. I think a linear scaling based on the resolution reduction should do it.
              • 4. Re: Particle Playground in RAM preview
                Mylenium Most Valuable Participant
                Hehe, technically nothing needs to be fixed, but of course it would be desirable to work in relative sizes/ units in such cases (and several others). On that I can agree. ;-)

                Mylenium
                • 5. Re: Particle Playground in RAM preview
                  craulmedia Level 1
                  desirable???

                  it's essential!!

                  so, what do you mean by "technically nothing needs to be fixed"?

                  what you are exactly talking about?
                  • 6. Re: Particle Playground in RAM preview
                    Level 1
                    I agree with Thomas. When RAM preview gives results at odds with the production render for a known and correctable reason, it "needs to be fixed". The alternative of warning the user is lousy. The alternative of doing nothing is a signal the company places low priority on this product.

                    I've submitted a bug report / feature request on this issue.
                    • 7. Re: Particle Playground in RAM preview
                      craulmedia Level 1
                      b a signal the company places low priority on this product

                      thank you Richard. Now all my thoughts about CS4 make sense.

                      I'm a motion graphics designer and i rarely have do work in photoshop but strangely some certain power lead me to be highly concentrated on every corner of photoshop development in the last couple of months (lets say 12).

                      that's sad, because Ae still feel to me working with version 7.

                      sorry folks...
                      • 8. Re: Particle Playground in RAM preview
                        Mylenium Most Valuable Participant
                        >desirable???
                        >it's essential!!
                        >so, what do you mean by "technically nothing needs to be fixed"

                        Not really. Working with relative units has disadvantages, too (think of the million people whose brain will explode when suddenly they have to set positions or item sizes in fractions of percent...). And technically nothing needs to be fixed - the current behavior is correct in terms of the underlying math and predictable by the user, the only real problem is that Adobe does a pretty poor job of communicating it to the user. If you get my meaning - you will want to work at reduced resolutions all the time to speed up interactivity, but you usually do not want it to make your work less predictable. They are still two different things, though. One could also argue that the flaw is simply in the effect/ plug-in. By all means, within the ranks of the AE API (as I understand it), it could just as well request the full resolution buffer, but then again, I don't know enough of that nor do I know anything about the licensing stuff that futzing with the code may touch upon, as apparently the effect originated outside Adobe a long time ago...

                        Mylenium
                        • 9. Re: Particle Playground in RAM preview
                          craulmedia Level 1
                          :( Thanks for the attempt to explain Mylenium.
                          • 10. Re: Particle Playground in RAM preview
                            Level 1
                            Mylenium - Either you or I are missing the point. In my view there need not be any change in how a user would input parameters into an effect. For example, Force Radius would still be entered as a number measured in pixels, not a percent of screen size. The change would be "behind the scenes". If Ae was asked to do a RAM preview at half-resolution, for example, for that preview it would multiple the number in original pixels by two to get the number of 2x pixels which gives the same fraction of screen size. My experiments show hat this would give the same (or very nearly the same) behavior in the preview as will be seen in the final rendering. The same behind-the-scenes temporary conversion must be made in speeds expressed as pixels per frame or any other parameter with pixel dimensions. This is just a matter of the RAM preview engine knowing which effect parameters are dimensioned in pixels and what resolution it is being asked to use - both easily knowable. Again, the parameter values entered by the user would be unchanged. No need for relative units as far as the user is concerned.
                            I agree that the current behavior does what the coders intended, but giving misleading previews is a serious weakness if fixing it has no negative side effects. I do not agree that if Adobe warns users of this weakness, all is hunk-dory.
                            Am I missing something?
                            • 11. Re: Particle Playground in RAM preview
                              Mylenium Most Valuable Participant
                              >Mylenium - Either you or I are missing the point.

                              No, actually not. We are both right and both helpless in changing the matter. ;-) You are both not considering, that AE's internal measure is pixels. It has no such thing as an abstract "world unit" as one can setup in 3D programs. Therefore, any physics are based either on absolute pixels or percentages of those pixels, at best quantized to the sub-pixel precision grid and that is dependent on the comp resolution/ size. For "predictable" behavior independent of the resolution, you would basically have to treat everything as a procedural 3D item, so the sampling is based on testing the 3D intersection, e.g. with a procedurally defined ramp "texture".... It's really more complex than it looks on first sight, so for the time being, we will probably have to live with these limitations.

                              Mylenium
                              • 12. Re: Particle Playground in RAM preview
                                craulmedia Level 1
                                > we will probably have to live with these limitations.

                                no we don't.
                                • 13. Re: Particle Playground in RAM preview
                                  Mylenium Most Valuable Participant
                                  Why am I not surprised about your answer? 8-O

                                  Mylenium
                                  • 14. Re: Particle Playground in RAM preview
                                    craulmedia Level 1
                                    coz you're an old stager in this biz :P
                                    • 15. Re: Particle Playground in RAM preview
                                      Andrew Yoole MVP & Adobe Community Professional
                                      The limitations with Particle Playground have existed since it's arrival in AE - version 5 0r 6, I think. It has always been a rather cumbersome and hard to use tool, in my opinion. It's always struck me as slightly experimental.

                                      There are, of course, other particle generators within AE, including CC Particle World. But personally, Trapcode Particular is the third party plugin I use more than any other - it is quite simply the most useful plugin I've ever bought for AE, and worth every cent.
                                      • 16. Re: Particle Playground in RAM preview
                                        craulmedia Level 1
                                        > Trapcode Particular is the third party plugin I use more than any other - it is quite simply the most useful plugin I've ever bought for AE,

                                        b and worth every cent.

                                        if you have the dime, everything will be fine...

                                        just a note for the guys from the dev-team who probably may stumble over this thread: i'm not paying for Ae using it on a "experimental basis".
                                        There are two presumptions: you are not capable of properly coding or lets say, having your software-development under control, or you are simply NOT WILLED to take a look into your code to see what else can be managed because you're so distracted by having this app work in somewhat future of Apples somewhat architecture?

                                        i'm in serious anger with Ae every day using it. i don't think i need a higher degree in mathematics just to be able to control a pretty self-explanatory software. if software lacks in usability thus lacking in performance, why someone should spend any future dime on it?

                                        I believe it has all to do with bureaucracy and fund, just to enhance a software systematically from version to version, not pushing the features at once whilst having them already in the top drawer since ages.

                                        it's pure business. it has nothing to do with customer satisfaction nor with customer experience.

                                        though, this forums and all it's peoples input from all aspects did had an impact on development. without it, we still would stuck in the middle 90ies.

                                        Thanks for sharing.

                                        personally i got tired of all this technical drawbacks. it caused me a lot of damage to my health, non billable hours and suffering in my
                                        profession as a digital artist which i've started with pure passion.

                                        I will quit my job and start doing something that makes really sense to me and my fellow men rather than hanging around for days/nights in front of a screen filled with problems.

                                        I release myself from this forum. i wish you all good luck for the future and keep pounding.

                                        cheers,
                                        Thomas
                                        • 17. Re: Particle Playground in RAM preview
                                          Adolfo Rozenfeld Adobe Employee
                                          Richard: Would you like to send a project in which this behavior is really evident? No need for source files or anything like that.
                                          If you would, this is my address: ar@adolforozenfeld.com

                                          Adolfo Rozenfeld - Adobe
                                          • 18. Re: Particle Playground in RAM preview
                                            Level 1
                                            A reply by direct email was sent to Aldolfo enclosing the project file which generated the original post of this thread.
                                            • 19. Re: Particle Playground in RAM preview
                                              Adolfo Rozenfeld Adobe Employee

                                              Got it. Thank you.

                                              • 20. Re: Particle Playground in RAM preview
                                                imagex ideas Level 1

                                                Adolfo - Have you learned anything about causes and fixes for the problem with RAM preview at less than full resolution?

                                                • 21. Re: Particle Playground in RAM preview
                                                  Adolfo Rozenfeld Adobe Employee

                                                  imagex: I discussed it briefly with someone before getting your project. When I did receive it, it went to the proper data base. Which leads me to an important point here - please understand that if engineers had to report back all the time to specific users' concerns, the application would never move forward

                                                  In other words, it's extremely useful that you guys provide example projects or whatever additional info that helps in isolating a potential issue. But also understand that in many cases, there can't be a direct answer other than knowing that it'll be investigated properly. In other cases, it may be a known issue or even a limitation that is part of the design, so it may be easier to come back with feedback in those cases. In any case, the system is designed so that your concerns don't slip through a crack, not to let you know immediately the outcome

                                                  • 22. Re: Particle Playground in RAM preview
                                                    imagex ideas Level 1

                                                    Adolfo - Your last post is clear.  My problematic project has been added to an Adobe database and I should not expect to get any further help on the issue.

                                                     

                                                    However, I was misled by your post asking for my project file.  Without the disclaimer you just sent, I believed I would get at least some response.  Clearly your engineers can't deal with every problematic issue raised in these forums, but if one of them asks for input from a customer without further disclaimer, the customer will generally expect his input to be examined and responded to, as did I.

                                                     

                                                    I suggest you "can" such a disclaimer and add it to future requests for customer input.

                                                    • 23. Re: Particle Playground in RAM preview
                                                      Adolfo Rozenfeld Adobe Employee

                                                      You are absolutely right, Imagex. In fact, I was about to state that as a reply when you sent your message. In fact, I tried to investigate the issue quickly but couldn't get to anything useful before passing it to where it should be. I apologize if you got the impression that I could certainly get back to you with a definitive statement. I thought I could get an answer with a couple of questions. My mistake. That's not always possible, and I should have said it clearly.