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Dx11 mesh questions, geometry buffer etc

I’m a bit stuck with the new dx11 pipeline, i’ve read all the help topics i can find, including the ‘DirectX 11 Rendering Techniques I workshop’ and I still can’t work out how to feed the spread of point positions into geometry buffer in the correct format to create a normal mesh.

I just want to create a basic flat mesh/grid and be able to vary the z position of each point.
Any further help or tips much appreciated
thanks

Hola,

Basically you use IndexedGeometryBuffer and you have to set the InputElement correctly according to your combined input spread.

See attached.

I also added the (almost) equivalent to normals (mesh) aka facenormals which is a contribution.

I think the texture coordinates are not 100% right. If someone can correct me, thats nice.

MeshJoin DX11.rar (11.7 kB)

Thank Tekcor,
unfortunately your patch has just confused me more! I thought I pretty much understood the demonstration patches from the workshop materials, but I understand even less what’s going in yours.
It seems to produce a pretty messy shape, not a flat grid?

What is the relation between the spread of vertices and the spread of indices?

How do I know what to input into the input element? The dx11 render techniques workshop patches only have 2 items going into each input, position and texture coordinates, do i need the normal as well, even if i’m only working with wireframe?

thanks, i had enough of a basic grasp of this stuff to work with dx9, but it’s all got a bit more complicated now!

there was a contribution that I can’t now find, that has some geomfx in it, if all your doing is distorting a 3d mesh or grid that should do you, but you’ll have to go look through them yourself, I couldn’t find them in the 1st 2 pages of hits!

I’m not sure what contribution you’re referring me to, but looking for it did lead me to a contribution of dx11 nodes which I get the impression had been added to the pack, but I didn’t seem to have them already for some reason.

Anyway, it contains Geometry Split, which is what i’d been looking for really, but unsurprisingly it doesn’t behave the same as the equivalent nodes in dx9.
When i split the vertices out of a simple grid, change the values for the points’ z position and then recombine using geometrybuffer join then it’s no longer 1 smooth mesh, instead the triangles that make up the mesh no longer meet each other at their corners.

Can someone explain what I need to do to fix this, thought it might have been something to do with topology, adjacency or something, but no joy. I know it comes down to my lack of knowledge to do with vertices, indecises, normals etc, which I need to learn properly, but for now, I really need to know just how to deform a simple grid! It was one of the first things I learnt in vvvv, and used it plenty of times, simple but effective it was… now its not so simple anymore!

I understand that you can do without indexes in DX11? Tell me what I’m doing wrong? Tried all topologies, point still not connected correctly (

patch to previous post.

mesh.v4p (10.5 kB)

@arturmihel: you haven’t seen anything because for some reason triangle vertex order is reversed in sphere ex9 and the default rendering in dx11 is back-face culling. if you create a rasterizer node and set it NoCullSimple you get the sphere, also if you deal with indexed geometry you have to use indices at dx11 side too with IndexedGeometryBuffer. If you use simple GeometryBuffer it will create the topology from every 2-32nd chunks of vertices. see the corrected patch below:

mesh_corrected.v4p (12.4 kB)

Thanks for the answer! All somehow became entangled with the geometry in dx11) I was hoping that no indexes will be easy to build surfaces in jitter example. Well, probably dx11 concept is still evolving.

well indices are just a way to reduce datasize by storing common vertices only once but you can build a geometry sequencially too, it’s up to you, it doesn’t have anything to do with evolving.

Hey @arturmihel: you should get in touch with Pixar and let them know that DX11 is still evolving and that MS is somehow confused about it; they collaborate with Microsoft - to code something which somehow involves DX11 technology, as it is possible to see here - on fast GPU drawing libraries.
Oh, also this guy should be aware of this.
Let us know what they possibly answer.

)))) h99, very funny, and i do that. I’m sorry, I did not clearly expressed. I meant that develops implementation DX11 to VVVV. Maybe I’m wrong, but the lack of GeometryBuffer (Split) says about it. I just would like to be able to quickly create geometry by default, without specifying indexes. But in general I am very grateful to the developers for such a terrific product, and do not consider me trolled) PS sorry for the English, it is not my native language.

Yes, I guessed it ;)
For me, it has been just a chance to post a couple of links in the forum…
Have a nice day!