# DX11 DX11-Window Rect vs render target buffer size.

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I just realize that doesnt matter the size I specifie on the swap chain desc buffer, it always paints the entire window rect? Why this happens? I mean, Lets say I set everything to 640x480( swapchains backbuffer/rendertarget), if my window is 700x800 it will all be cleared by my clear color, why? What is the size of the swapchain desc for?

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What size is your viewport? If you are rendering to a 700x800 viewport it will fill it with the 640x480 rendertarget... I believe.

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The viewport have the same size of the back buffer specified on the swap chain desc.

Doesnt matter what value I put on the viewport or in the buffer description, notting changes, but Im not rendering anything, just clearing the render target with a color and presenting..

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The size you give for the swap chain will specify the size of the backbuffer. No matter what size you choose, the backbuffer is scaled to the size of the window's client area. If you don't want this behavior, you'll have to implement it manually either by adjusting your viewport or through some other means.

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But adjusting the viewport dont works either!

What I want specifialy is let a space for the status bar that my app have( The status bar is drawed at the window client area)

some code:
//here I change the original size of the window, so lets say it have height 480+20=500MoveWindow( hWnd_p, wndrect_p.left, wndrect_p.top, wndrect_p.right, wndrect_p.bottom+sbHeight, TRUE );//the swap chain description is filled with the original wndrect values(640x480)DXGI_SWAP_CHAIN_DESC		sw = {0};//IN						sw.BufferCount						= 2;					sw.BufferDesc.Format					= DXGI_FORMAT_R8G8B8A8_UNORM;					sw.BufferDesc.RefreshRate.Numerator		= 60;					sw.BufferDesc.RefreshRate.Denominator	= 1;					sw.BufferDesc.Scaling					= DXGI_MODE_SCALING_CENTERED;					sw.BufferDesc.ScanlineOrdering			= DXGI_MODE_SCANLINE_ORDER_UNSPECIFIED;					sw.BufferDesc.Width						= wndrect_p.right;					sw.BufferDesc.Height					= wndrect_p.bottom;						sw.BufferUsage						= DXGI_USAGE_RENDER_TARGET_OUTPUT;						sw.Flags							= NULL;						sw.OutputWindow						= hWnd_p;					sw.SampleDesc.Count						= 1;					sw.SampleDesc.Quality					= 0;						sw.SwapEffect						= DXGI_SWAP_EFFECT_DISCARD;						sw.Windowed							= TRUE;//and so is the view port://note that I alredy tried a lot of values here, like toplefx/y = 0 and width/height=100, notting changes.D3D11_VIEWPORT vp = {0};		vp.Width = (FLOAT)wndrect_p.right;		vp.Height = (FLOAT)wndrect_p.bottom;		vp.MinDepth = 0.0f; vp.MaxDepth = 1.0f;		vp.TopLeftX = (FLOAT)wndrect_p.left; vp.TopLeftY = (FLOAT)wndrect_p.top;	pDIContext_p->RSSetViewports( 1, &vp );//Render Stage//here is how Im setting the rendertarget view:	ID3D11Texture2D *pTex2DBBuff = NULL;//resource to get the back buffer	if( pSC_p->GetBuffer( 0, __uuidof(ID3D11Texture2D), (VOID**)&pTex2DBBuff ) != S_OK ) return E_FAIL;	if( pDevice_p->CreateRenderTargetView( pTex2DBBuff, NULL, &pRTV_p ) != S_OK ) return E_FAIL;g_pDIContext->OMSetRenderTargets( 1, &g_pRTV, NULL);//Output Merger Stage`

How can I make it render just on a part of the client area? Am Im doing something wrong?
When I create the render target view Im specifiing NULL as description, on the sdk it says "Set this parameter to NULL to create a view that accesses all of the subresources in mipmap level 0." My subresource is the backbuffer specified at the swap chain desc and have the righ size. Checking this struct at the SDK dont help much, I cant find a member data that would have something to do with this, but Im a moron, maybe it do...It have a member View Dimensions(enum), but the values possible are weird, I cant understand:
D3D11_RTV_DIMENSION_UNKNOWN = 0,
D3D11_RTV_DIMENSION_BUFFER = 1,
D3D11_RTV_DIMENSION_TEXTURE1D = 2,
D3D11_RTV_DIMENSION_TEXTURE1DARRAY = 3,
D3D11_RTV_DIMENSION_TEXTURE2D = 4,
D3D11_RTV_DIMENSION_TEXTURE2DARRAY = 5,
D3D11_RTV_DIMENSION_TEXTURE2DMS = 6,
D3D11_RTV_DIMENSION_TEXTURE2DMSARRAY = 7,
D3D11_RTV_DIMENSION_TEXTURE3D = 8

..
Its problay simple stuff..Render to just a part of client area is commom, someones alredy figured it out..o.o

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Someone could also explain me the D3D11_BUFFER_RTV struct please...On the SDK it have 2 members, but it have 4 members:
rtvdesc.Buffer.ElementOffset
rtvdesc.Buffer.ElementWidth
rtvdesc.Buffer.FirstElement
rtvdesc.Buffer.NumElements
What is a buffer element?

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When you give the swap chain a handle to the window, it pretty much "owns" the entire client area. There's not really a good way to make it play nice with other child windows in the same client area.

What might be an easier approach for you would be to create the status bar as a child window, and then make another borderless child window that fills up the rest of the main window's client area. Then you can just present to that child window.

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Hi..
I just figure out that the view port works, the stuff is rendered and clipped just on the view port part of the client area, but the entire client area is cleared(painted) with the clear color... Im sure must be some detail that I didnt find yet..

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