Direct3D9 fullscreen app - deformed renderering - directx

Question

I have been hardly coding on a Direct3D9 based game. Everything went excellent util I hit a big problem. I created a class that wraps the process of loading a mesh from a .x file. I successfully loaded a cube with only one face visible. In theory, that face should look like a square but it is actually rendered as a rectangle. I am quite sure that there is something wrong with the D3DPRESENT_PARAMETERS structure. Down bellow are only the most important lines of my application's initialization.
First part to be created is the focus window:
HWND hWnd = CreateWindowEx(0UL, L"NewFrontiers3DWindowClass", Title.c_str(), WS_POPUP | WS_EX_TOPMOST, 0, 0, 1280, 1024, nullptr, (HMENU)false, hInstance, nullptr);
Then I fill out the D3DPRESENT_PARAMETERS structure.
D3DDISPLAYMODE D3DMM;
SecureZeroMemory(&D3DMM, sizeof(D3DDISPLAYMODE));
if(FAILED(hr = Direct3D9->GetAdapterDisplayMode(Adapter, &D3DMM)))
{
// Error is processed here
}
PresP.BackBufferWidth = D3DMM.Width;
PresP.BackBufferHeight = D3DMM.Height;
PresP.BackBufferFormat = BackBufferFormat;
PresP.BackBufferCount = 1U;
PresP.MultiSampleType = D3DMULTISAMPLE_NONE;
PresP.MultiSampleQuality = 0UL;
PresP.SwapEffect = D3DSWAPEFFECT_DISCARD;
PresP.hDeviceWindow = hWnd;
PresP.Windowed = false;
PresP.EnableAutoDepthStencil = EnableAutoDepthStencil;
PresP.AutoDepthStencilFormat = AutoDepthStencilFormat;
PresP.Flags = D3DPRESENTFLAG_DISCARD_DEPTHSTENCIL;
PresP.FullScreen_RefreshRateInHz = D3DMM.RefreshRate;
PresP.PresentationInterval = PresentationInterval;
Then the Direct3D9 device is created, followed by the SetRenderState functions.
Next, the viewport is assigned.
D3DVIEWPORT9 D3D9Viewport;
SecureZeroMemory(&D3D9Viewport, sizeof(D3DVIEWPORT9));
D3D9Viewport.X = 0UL;
D3D9Viewport.Y = 0UL;
D3D9Viewport.Width = (DWORD)D3DMM.Width;
D3D9Viewport.Height = (DWORD)D3DMM.Height;
D3D9Viewport.MinZ = 0.0f;
D3D9Viewport.MaxZ = 1.0f;
if(FAILED(Direct3D9Device->SetViewport(&D3D9Viewport)))
{
// Error is processed here
}
After this initialization, I globally declare some parameters that will be used later.
D3DXVECTOR3 EyePt(0.0f, 0.0f, -5.0f), Up(0.0f, 1.0f, 0.0f), LookAt(0.0f, 0.0f, 0.0f);
D3DXMATRIX View, Proj, World;
The update function looks like this:
Mesh.Render(Direct3D9Device);
D3DXMatrixLookAtLH(&View, &EyePt, &LookAt, &Up);
Direct3D9Device->SetTransform(D3DTS_VIEW, &View);
D3DXMatrixPerspectiveFovLH(&Proj, D3DX_PI/4, 1.0f, 1.0f, 1000.f);
Direct3D9Device->SetTransform(D3DTS_PROJECTION, &Proj);
D3DXMatrixTranslation(&World, 0.0f, 0.0f, 0.0f);
Direct3D9Device->SetTransform(D3DTS_WORLD, &World);
The device is not a null pointer.
I recently realized that there is no difference between declaring and setting up a view port and not doing so.
If there is anybody who can point me to the right answer, please help me solve this annoying problem.

Answer 1

If you don't set any transformation matrices, so the identity transformation is applied to your mesh, then face of the cube will be stretched to the same shape of the viewport. If your viewport isn't square (eg. it's the same size as the screen) then your cube's face also won't be square.
You can use a square viewport to workaround this problem, but that will limit your rendering to just that square on the screen. If you want to render to the entire screen you'll need to set a suitable projection matrix. You can calculate a normal perspective perspective matrix using D3DXMatrixPerspectiveFovLH. If you want an orthogonal perspective, where everything is the same size regardless of the distance from the camera, then use D3DXMatrixOrthoLH to calculate the perspective matrix. Note that if you use your viewport's width and height with the later function it will shrink your cube. A unit size cube will be rendered as a single pixel on the screen. You can either use a world or view transform to scale it up again, or use something like width/height and 1 as your width and height parameters to D3DXMatrixOrthoLH.
If you go with D3DXMatrixPerspectiveFovLH then you want something like this:
D3DXMatrixPerspectiveFovLH(&Proj, D3DX_PI/4, (double) D3DMM.Width / D3DMM.Height,
1.0f, 1000.f);

Answer 2

I think your problem not in D3DPP parameters but in your projective matrix. If you use D3DXMatrixPerspectiveFovLH, check aspect ratio to be 1280 / 1024 = 1.3333f