void RenderFrame(void)
{
    D3DXMATRIX matView, matProjection;
    D3DXMATRIX matFinal;

    // create a view matrix
    D3DXMatrixLookAtLH(&matView,
    &D3DXVECTOR3(0.0f, 9.0f, 24.0f),   // the camera position
    &D3DXVECTOR3(0.0f, 0.0f, 0.0f),    // the look-at position
    &D3DXVECTOR3(0.0f, 1.0f, 0.0f));   // the up direction

    // create a projection matrix
    D3DXMatrixPerspectiveFovLH(&matProjection,
    (FLOAT)D3DXToRadian(45),                    // field of view
    (FLOAT)SCREEN_WIDTH / (FLOAT)SCREEN_HEIGHT, // aspect ratio
    1.0f,                                       // near view-plane
    100.0f);                                    // far view-plane

    // create the final transform
    matFinal = matView * matProjection;

    devcon->ClearRenderTargetView(backbuffer, D3DXCOLOR(0.0f, 0.2f, 0.4f, 1.0f));

    devcon->ClearDepthStencilView(zbuffer, D3D11_CLEAR_DEPTH, 1.0f, 0);

    UINT stride = sizeof(VERTEX);
    UINT offset = 0;
    devcon->IASetVertexBuffers(0, 1, &pVBuffer, &stride, &offset);
    devcon->IASetIndexBuffer(pIBuffer, DXGI_FORMAT_R32_UINT, 0);
    devcon->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);

    devcon->UpdateSubresource(pCBuffer, 0, 0, &matFinal, 0, 0);
    devcon->DrawIndexed(24, 0, 0);

    swapchain->Present(0, 0);
}