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Hello!

I resently "developed" a problem, no idea how or how to solve it.

The thing is, when i rotate a model in the X axis, it rotates the Y axis,and the Y rotates the X axis.
To solve the problem i started to mess around with the vertex shader to find a solution.. with out any Luck!

My question is now, is this correct? (psudo code)

1 : Set my ViewProjection to the shader as a TRANPOSED matrix.
2 : calculate World * ViewProjection
3 : calculate VertexPos * (World*Viewprojection)

That is the way i have been doing it befor and it workt perfect by then.
any helps would be nice! cheers!

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Give the ObjectTransformationMatrix, ViewMatrix and ProjectionMatrix to the shader.
Multiply from object space to screen space in the vertex shader and give all 4 types of vertex position to the pixel shader.
ObjectSpace -> WorldSpace -> CameraSpace -> ScreenSpace

If you try to optimize by making one matrix on the CPU, you will sooner or later have to split it to support more advanced materials.

Each object should store:
Normalized orthogonal 3x3 matrix for fast rotation.
X,Y,Z scaling vector for setting the size.
X,Y,Z translation vector for moving.

Multiply the object's normalized orthogonal 3x3 matrix with a rotation matrix, orthogonalize to remove rounding errors and let the compiler optimize the multiplications with 0 and 1.
[url="http://en.wikipedia.org/wiki/Rotation_matrix"]http://en.wikipedia....Rotation_matrix[/url]

Scale object's normalized orthogonal 3x3 matrix with the scaling vector and insert it to a 4x4 matrix together with the translation vector to create the final ObjectTransformationMatrix that you can give to your shader.

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well, most of the stuff you said i do understand.

what i dont understand isent why my matrix calulation wont work :

(World * View * Projection) * localpos;

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If you are applying the multiplication in screen space, it will rotate in screen space. Only apply rotations to the matrix that convert object space to world space.

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How are you calculating your world transformation? If you think about it, the world matrix is simply a mapping from one space to another, so if it is being done incorrectly then there are really only two possible reasons why - 1. the mapping calculated is wrong or 2. the two spaces are related in the way that you think they are.

I'm pretty sure that it is either the calculation is incorrect, or possibly that the arguments on your matrix multiplication should be flipped - i.e. mul(vector, matrix) should be mul(matrix, vector) or vice versa. Are you able to post the relevant code snippets?

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• ### Similar Content

Dispatch(32, 24, 1)

I'm attempting to implement some basic post-processing in my "engine" and the HLSL part of the Compute Shader and such I think I've understood, however I'm at a loss at how to actually get/use it's output for rendering to the screen.
Assume I'm doing something to a UAV in my CS:
RWTexture2D<float4> InputOutputMap : register(u0); I want that texture to essentially "be" the backbuffer.

I'm pretty certain I'm doing something wrong when I create the views (what I think I'm doing is having the backbuffer be bound as render target aswell as UAV and then using it in my CS):

DXGI_SWAP_CHAIN_DESC scd; ZeroMemory(&scd, sizeof(DXGI_SWAP_CHAIN_DESC)); scd.BufferCount = 1; scd.BufferDesc.Format = DXGI_FORMAT_R8G8B8A8_UNORM; scd.BufferUsage = DXGI_USAGE_RENDER_TARGET_OUTPUT | DXGI_USAGE_SHADER_INPUT | DXGI_USAGE_UNORDERED_ACCESS; scd.OutputWindow = wndHandle; scd.SampleDesc.Count = 1; scd.Windowed = TRUE; HRESULT hr = D3D11CreateDeviceAndSwapChain(NULL, D3D_DRIVER_TYPE_HARDWARE, NULL, NULL, NULL, NULL, D3D11_SDK_VERSION, &scd, &gSwapChain, &gDevice, NULL, &gDeviceContext); // get the address of the back buffer ID3D11Texture2D* pBackBuffer = nullptr; gSwapChain->GetBuffer(0, __uuidof(ID3D11Texture2D), (LPVOID*)&pBackBuffer); // use the back buffer address to create the render target gDevice->CreateRenderTargetView(pBackBuffer, NULL, &gBackbufferRTV); // set the render target as the back buffer CreateDepthStencilBuffer(); gDeviceContext->OMSetRenderTargets(1, &gBackbufferRTV, depthStencilView); //UAV for compute shader D3D11_UNORDERED_ACCESS_VIEW_DESC uavd; ZeroMemory(&uavd, sizeof(uavd)); uavd.Format = DXGI_FORMAT_R8G8B8A8_UNORM; uavd.ViewDimension = D3D11_UAV_DIMENSION_TEXTURE2D; uavd.Texture2D.MipSlice = 1; gDevice->CreateUnorderedAccessView(pBackBuffer, &uavd, &gUAV); pBackBuffer->Release();
After I render the scene, I dispatch like this:
gDeviceContext->OMSetRenderTargets(0, NULL, NULL); m_vShaders["cs1"]->Bind(); gDeviceContext->CSSetUnorderedAccessViews(0, 1, &gUAV, 0); gDeviceContext->Dispatch(32, 24, 0); //hard coded ID3D11UnorderedAccessView* nullview = { nullptr }; gDeviceContext->CSSetUnorderedAccessViews(0, 1, &nullview, 0); gDeviceContext->OMSetRenderTargets(1, &gBackbufferRTV, depthStencilView); gSwapChain->Present(0, 0); Worth noting is the scene is rendered as usual, but I dont get any results from the CS (simple gaussian blur)
I'm sure it's something fairly basic I'm doing wrong, perhaps my understanding of render targets / views / what have you is just completely wrong and my approach just makes no sense.

If someone with more experience could point me in the right direction I would really appreciate it!

On a side note, I'd really like to learn more about this kind of stuff. I can really see the potential of the CS aswell as rendering to textures and using them for whatever in the engine so I would love it if you know some good resources I can read about this!

Thank you <3

P.S I excluded the .hlsl since I cant imagine that being the issue, but if you think you need it to help me just ask

P:P:S. As you can see this is my first post however I do have another account, but I can't log in with it because gamedev.net just keeps asking me to accept terms and then logs me out when I do over and over

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struct CameraBufferType
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XMFLOAT3 cameraPosition;
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• By mellinoe
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