Hello,

I dispair of rendering an obj-quad-mesh with DirectX 11. My meshloader seems correct, because the wireframe mode is shown properly.

I found out that obj-meshes are oriented counterclockwise, but DirectX normally is clockwise.
So I set the rasterizer "FrontCounterClockwise" to true and outputtopology of my Hullshader to "triangle_ccw".

The big confusion comes with the constant Hullshader and Domainshader. I tired to make a sketch of one quad (because all my meshes are quad-meshes)

[source lang="cpp"]
// patch[3]
// +--------- e1 ---------+ patch[2]
// | in1 in1 |
// | | | |
// UV.y e0 ---+--in0-----+---- e2
// | | | |
// | | | |
// +--------- e3 ---------+ patch[1]
// patch[0]
// UV.x

// e = edge, in0 = inside[0], in1 = inside[1], UV = SV_DomainLocation of Domainshader

HS_CONSTANT_Out ConstantHS(InputPatch<VS_Out, INPUT_PATCH_SIZE> patch, uint PatchID : SV_PrimitiveID){
HS_CONSTANT_Out output;

output.Edges[0] = 2; //left edge
output.Edges[1] = 3; //upper edge
output.Edges[2] = 2; //right edge
output.Edges[3] = 3; //lower edge
output.Inside[0] = 3; //horizontal
output.Inside[1] = 2; //vertical

return output;
}
[/source]

So, first why is DirectX so weird: is there an explanation for the edges being clockwise? Did I forget to set some value?

Furthermore my mesh isn't drawn correctly. I can see through it and some patches are culled although they are in front of everything. (see attachment)
Looks like the depthbuffer is not cleared, but my render-function is doing "ClearDepthStencilView"

I'm trying to fix that issue since a week or so but I only get even more strange results.

Does someone has a clue or can give me an advice what I could do to find the error?

Thank you very much!


[EDIT: pictures deleted, better ones see below]
[EDIT 2: (just information) not only the edges are clockwise, everything in the shaders is clockwise! Even with FrontCounterClockwise set!]

Any suggests?

Thank you for your answer. ;)

Well, the whole pipeline isn't so small that it can be posted.

Topic outputtopology: I set the outputtopology to triangle_ccw, but the edges are still clockwise.
I find that a bit strange. Is there a reason for that? (another option to set?)

I'll try out PIX... That sounds like it's a good point to continue. Thanks.

Can reverse vertex winding occur even if the wireframe is shown/culled correctly? (cause wireframe's ok)

Wireframe coming....

The advice with PIX helped me out! I found a something.
I bound a custom (extra) rendertarget/depthstencil to the shader-pipeline. If I don't do that (and use "DXUT-standard"), everything looks good.
So the shaders should be right (same shaders in both pipelines). If I switch to "new" pipeline and back to standard-pipeline (while program is running), the "mesh" is broken again!

What I'm doing:
1) create Texture2D for rendertarget/depthstencil with rendertargetview and depthstencilview

2) render:
- clearrendertargetview/cleardepthstencilview
- set shaders, rasterizerstate, inputlayout, constantbuffers
- set vertexbuffer, indexbuffer
- set primitivetopology (quads => 4_control_point_patchlist)
- OMSetRendertarget (with rendertargetview and depthstencilview)
- drawindexed
- reset everything that was set above

Did I forgot something?

Rasterizer:
[source lang="cpp"]
//solid
D3D11_RASTERIZER_DESC RasterDesc;
ZeroMemory(&RasterDesc, sizeof(D3D11_RASTERIZER_DESC));
RasterDesc.FillMode = D3D11_FILL_SOLID;
RasterDesc.CullMode = D3D11_CULL_BACK;
RasterDesc.FrontCounterClockwise = TRUE; //counterclockwise!
RasterDesc.DepthClipEnable = TRUE;
V_RETURN(pd3dDevice->CreateRasterizerState(&RasterDesc, &_g_pRasterizerStateSolid));

//wireframe
RasterDesc.FillMode = D3D11_FILL_WIREFRAME;
V_RETURN(pd3dDevice->CreateRasterizerState(&RasterDesc, &_g_pRasterizerStateWireframe))
[/source]
In Hullshader outputtopology is triangle_ccw, mesh ist loaded from obj (counterclockwise) with indexbuffer (=> drawIndexed)


[EDIT: I added a depthstencilstate and switched the depth-test off => "mesh"-bug was mirrored: the missing corner in face of bigguy is then on the left side! I don't understand this...]

[EDIT: sorry, that was a wrong idea... deleted]

Wohoo! I got it! It's the viewport!

If I comment the viewport out, everything is shown right (in both pipelines!). At least it seems to be right.
(except that the mesh is too small and in the upper-left corner, because of "old" viewport)

Thanks very much Jason Z ;)

In case someone has the same problem. Here's the solution:

[source lang="cpp"]
D3D11_VIEWPORT old;
UINT viewport_nr = 1;
pd3dImmediateContext->RSGetViewports(&viewport_nr, &old);

D3D11_VIEWPORT vp;
ZeroMemory(&vp, sizeof(D3D11_VIEWPORT));
vp.Height = static_cast<FLOAT>(Height);
vp.Width = static_cast<FLOAT>(Width);
vp.TopLeftX = 0;
vp.TopLeftY = 0;
vp.MinDepth = 0; //attention: DO set this value (standard is 0)
vp.MaxDepth = 1; //attention: DO set this value (standard is 1)
pd3dImmediateContext->RSSetViewports(1, &vp);

//render (set up shaders..., DrawIndexed, reset shaders...)

//reset viewport (in my case because of supersampling => so that hud stays the same)
pd3dImmediateContext->RSSetViewports(viewport_nr, &old);
[/source]