On Thu, Jun 13, 2013 at 7:56 AM, Sletta Gunnar <gunnar.sle...@digia.com> wrote: > > On Jun 12, 2013, at 9:58 PM, Mark <mark...@gmail.com> wrote: > >> Hi Gunnar, >> >> I just tried your example out (from the new review link [1]) and >> you've truly done a amazing job! + you saved my days of fiddling >> around :) >> Big pros! It runs well on Qt with OpenGL on Windows. I haven't tried >> other instances. >> >> Again, an awesome job! >> >> Will this be added as an example to 5.1.0 or 5.1.1? It's not like it's >> blocking anything ;) > > Targeted at 5.1.1 now, it is by no means a showstopper :)
Hey, psst, have you tried out one of your own pitfalls? ^_- I bet you didn't, hehehe. I added 0.5 in my code for the X in the vertical lines and 0.5 for the Y in horizontal lines. Then multisampling looks sharp again. However, when doing that and disabling multisampling again the lines are off by one pixel.. I haven't looked into that yet why that happens. Regards, Mark > >> >> Cheers, >> Mark >> >> [1] https://codereview.qt-project.org/#change,58714 >> >> On Wed, Jun 12, 2013 at 8:54 AM, Mark <mark...@gmail.com> wrote: >>> On Wed, Jun 12, 2013 at 8:29 AM, Sletta Gunnar <gunnar.sle...@digia.com> >>> wrote: >>>>>> This graph concept might be a good usecase for a more complex example >>>>>> down the line though.. I'll keep it in mind and maybe it will be >>>>>> included in Qt in the future :) >>>>> >>>>> Oh... that sucks. >>>> >>>> I think so too, so I spent some time yesterday evening to put it together: >>>> https://codereview.qt-project.org/#change,58589 >>>> >>>> It does the background, grid, line and dropshadow as 4 separate geometry >>>> nodes and shows several new sides of the scene graph API. >>>> >>>> The line stroking is a bit crude as it doesn't account for the line angle >>>> so steep slopes will come out thinner, but it should be a good starting >>>> point. >>> >>> Oh wow! You're trying to do everything i tried in just a couple of >>> hours where i would spend several nights and not even get close to >>> what you just made. Thank you very much for this! >>>> >>>> cheers, >>>> Gunnar >>>> >>>>> Well, i guess i'm just gonna have to play with this >>>>> and see how it turns out. If (assuming i can figure it out) i get it >>>>> working i will certainly share my code in here or on this list. >>>> >>>>> >>>>>> >>>>>>> - for the dropshadow, do exactly the same as for the line, except you >>>>>>> can use the custom vertex shader to expand it a little bit more and >>>>>>> change the opacity to make it a more blurry. >>>>>> Here i really do wonder if it isn't easier to just make a simple line >>>>>> component and use QtGraphicalEffects for the shadowing... I guess >>>>>> experimenting with both will tell which option works best. >>>>>> >>>>>> >>>>>>> - for the gradient under the line, create a trianglestrip and colorize >>>>>>> it according based on the y position in the fragment shader. >>>>>> Yeah, figured it would be something like that. Will do. >>>>>>> >>>>>>>> >>>>>>>> 2. Another way i see is taking the OpenGL direct approach following >>>>>>>> the "OpenGLunderQML example [1]. I can probably work of that example, >>>>>>>> but i really try to stay away from doing direct opengl interaction.. >>>>>>> >>>>>>> Raw OpenGL has its benefits, which is why the example and the feature >>>>>>> is there, but I've been thinking that the primary usecase for >>>>>>> OpenGLUnderQML is when you have a game/cad app running and QML is just >>>>>>> the HUD controls. Using raw opengl for UI elements has the downside >>>>>>> that you don't get any inherited clipping, transformation, nor opacity >>>>>>> so things might be quite a bit more complicated to manage inside your >>>>>>> UI. >>>>>> Exactly my opinion as well. I try to stay away from raw opengl calls. >>>>>>> >>>>>>>> >>>>>>>> 3. A third possible way that i can think of is by throwing everything >>>>>>>> out and starting over in a very abstract manner. Making a bunch of >>>>>>>> small components (in C++) like: >>>>>>>> (note: this is still for the charting stuff [0]) >>>>>>>> - 1 component to draw the background with a little more power then a >>>>>>>> Rectangle. However, if i choose this route i might as well use the >>>>>>>> QtGraphicalEffects for the added power (gradients) since that provides >>>>>>>> it. >>>>>>>> - 1 component for drawing a grid on top of the gradient. >>>>>>>> - 1 component for drawing a line where i probably only provide the >>>>>>>> data indicating where the line should be. Again i can use >>>>>>>> QtGraphicalEffects on top of this to add additional shadow. However, i >>>>>>>> find the default OpenGL line drawing stuff (even with multisampling) >>>>>>>> of a very very very poor rendering quality. I'm really thinking of >>>>>>>> using the "vase renderer" for drawing a way sharper line [2] Another >>>>>>>> note, this might also be very interesting for you to draw way sharper >>>>>>>> "scene graph fonts" which at the moment still look quite blurry at >>>>>>>> it's best under desktop environments. >>>>>>> >>>>>>> The distancefield fonts are unhinted and this is why they look more >>>>>>> blurry than native fonts (at least on windows and potentially linux). >>>>>>> You can enable native rendering by sacrificing font scalability: >>>>>>> http://blog.qt.digia.com/blog/2012/08/08/native-looking-text-in-qml-2/ >>>>>>> >>>>>>>> - I'm stuck at how to animate the line as more data flows in.. >>>>>>>> >>>>>>>> I hope you can advice me here in picking an option to go for. It's all >>>>>>>> quite a bit of work and all likely has the same end result. Right now >>>>>>>> i'm leaning towards option 3 where i was trying to go for option 1 >>>>>>>> till this very moment. >>>>>>>> >>>>>>>> >>>>>>>> [0] http://i.stack.imgur.com/Zk2RG.png -- i try to make it look as >>>>>>>> crisp as this one >>>>>>> >>>>>>> >>>>>>>> [1] >>>>>>>> https://qt.gitorious.org/qt/qtdeclarative/trees/stable/examples/quick/scenegraph/openglunderqml >>>>>>>> [2] >>>>>>>> http://www.codeproject.com/Articles/226569/Drawing-polylines-by-tessellation >>>>>>>> >>>>>>>> >>>>>>>> On Mon, Jun 10, 2013 at 10:07 AM, Sletta Gunnar >>>>>>>> <gunnar.sle...@digia.com> wrote: >>>>>>>>> >>>>>>>>> On Jun 8, 2013, at 11:33 PM, Mark <mark...@gmail.com> wrote: >>>>>>>>> >>>>>>>>>> Hi, >>>>>>>>>> >>>>>>>>>> Back when the graphical effects where first showcased in a blog i was >>>>>>>>>> already kinda scared that there would be no C++ interface to use them >>>>>>>>>> from the C++ side. Now i find myself in the position where i want to >>>>>>>>>> use the DropShadow element from that very same module in custom QML >>>>>>>>>> Scene Graph module and give a line a shadow. >>>>>>>>>> >>>>>>>>>> I kinda - very much - dislike copying the relavant parts of the >>>>>>>>>> DropShadow code and re-create that in C++.. >>>>>>>>>> >>>>>>>>>> Is there a way that i can use DropShadow from the C++ side? >>>>>>>>> >>>>>>>>> There is no way to do this using pure C++ API. You could construct it >>>>>>>>> from c++ using QQmlComponent and set the source property by passing >>>>>>>>> it the item that creates the geometry node. >>>>>>>>> >>>>>>>>> cheers, >>>>>>>>> Gunnar >>>>>>>>> >>>>>>>>>> >>>>>>>>>> Regards, >>>>>>>>>> Mark >>>>>>>>>> _______________________________________________ >>>>>>>>>> Interest mailing list >>>>>>>>>> Interest@qt-project.org >>>>>>>>>> http://lists.qt-project.org/mailman/listinfo/interest >>>>>>>>> >>>>>>> >>>>> > _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
