[Interest] Qt3D How to draw 2D-Text always facing the Camera
volker.enderlein at ifm-chemnitz.de
Wed Dec 19 09:14:23 CET 2018
The number of Text2D elements is not known in advance and may differ.
It's a simulation environment, where some textual information is added
to a fairly high number of elements.
To avoid the data management for different kinds of entities my first
idea was to create a specialized Text2d entity that handles all the
gory details in a custom material and provides an option to always face
Am 19.12.2018 um 08:37 schrieb david crémoux:
> You're welcome.
> I will most probably have to implement the same feature in a near
> future for the project I'm currently working on.
> If making the custom camera is too much complex, there is a more basic
> way but involving more data management (depending on how much 2d text
> entities you have to display):
> You still use a specific frame graph branch with a layer filter but
> with an identity camera.
> Then you attach all your 2d text entities to your scene root entity
> and you update their transform/position on every camera transform/move.
> On 19-Dec-18 10:05, Volker Enderlein wrote:
>> Hi David,
>> thanks for the answer. I wasn't thinking of that, as my knowledge
>> about framegraphs is very limited. But this helps me further.
>> Cheers Volker
>> Am 18.12.2018 um 14:53 schrieb david crémoux:
>>> Hello Volker,
>>> I guess you can achieve it with regular QText2DEntity, with a
>>> specific frame graph branch in your rendering for your 2d text, a
>>> layer filter and a custom camera (based on your main camera).
>>> On 18-Dec-18 14:37, Volker Enderlein wrote:
>>>> Hi all,
>>>> when building a rather complex Qt3D-Scene I needed some 2D-Text
>>>> that has a 3D position, is always facing the camera, and fixed in
>>>> size, independent of the camera settings.
>>>> While looking over the components provided by Qt3D I stumbled
>>>> across Text2DEntity and thought about how it can be tweaked ot
>>>> fulfill my requirements.
>>>> As all my requirements can be done inside a shader I thought about
>>>> whether the QText2DMaterial that is used inside the class can be
>>>> replaced by a custom material. But unfortunately the material is
>>>> not accessible from outside.
>>>> Text2DEntity can be embedded in another class that applies the
>>>> camera information to it, but is there an easier solution to this
>>>> Cheers Volker
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