请D3D9达人们帮帮忙，关于贴图

holyodin

小弟我刚学D3D不久，今天在把位图加载并显示在屏幕上时发现图片出现比较严重的锯齿（图片本身没问题）。这在我以前用GDI时是不会有的。请问是怎么回事？以下是我的源码：
其中的位图文件大家随便拿一幅来试试就行了。谢谢！

#include "stdafx.h"
#include <d3d9.h>
#include "d3dx9.h"
#include "stdio.h"
#include "d3dx9tex.h"
#pragma comment(lib,"dxguid.lib")
#pragma comment(lib,"d3d9.lib")
#pragma comment(lib,"d3dx9.lib")

IDirect3D9* d3d_3D ;
IDirect3DDevice9*        d3d_Device ;
IDirect3DSurface9* surface;
HWND hWnd;
HINSTANCE hInst;
const int SCREENWIDTH = 1280;
const int SCREENHEIGHT = 960 ;
ATOM                                MyRegisterClass(HINSTANCE hInstance);
BOOL                                InitInstance(HINSTANCE, int);
bool initDirect3D(void);
void render(void);
void cleanUp (void);
LRESULT CALLBACK        WndProc(HWND, UINT, WPARAM, LPARAM);



int APIENTRY WinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR     lpCmdLine,
                     int       nCmdShow)
{
        MSG msg;
        MyRegisterClass(hInstance);       
        if (!InitInstance (hInstance, nCmdShow))
        {
                return FALSE;
        }
       
         while( msg.message!=WM_QUIT )
    {
        if( PeekMessage( &msg, NULL, 0,0 ,PM_REMOVE) )
        {
            TranslateMessage( &msg );
            DispatchMessage( &msg );
        }
                else
                {
                        render();
                }
               
    }
        cleanUp ();

        return msg.wParam;
}


ATOM MyRegisterClass(HINSTANCE hInstance)
{
        WNDCLASSEX wcex;

        wcex.cbSize = sizeof(WNDCLASSEX);
        wcex.style                        = CS_HREDRAW | CS_VREDRAW;
        wcex.lpfnWndProc        = (WNDPROC)WndProc;
        wcex.cbClsExtra                = 0;
        wcex.cbWndExtra                = 0;
        wcex.hInstance                = hInstance;
        wcex.hIcon                        = NULL;
        wcex.hCursor                = NULL;
        wcex.hCursor                = LoadCursor(NULL, IDC_ARROW);
        wcex.hbrBackground        = (HBRUSH)(COLOR_WINDOW+1);
        wcex.lpszMenuName        = NULL;
        wcex.lpszClassName        = "canvas";
        wcex.hIconSm                = NULL;

        return RegisterClassEx(&wcex);
}


BOOL InitInstance(HINSTANCE hInstance, int nCmdShow)
{
       

        hInst = hInstance;

        hWnd = CreateWindow("canvas", "Mydx" , WS_OVERLAPPEDWINDOW,
                CW_USEDEFAULT, 0, CW_USEDEFAULT, 0, NULL, NULL, hInstance, NULL);

        if (!hWnd)
        {
                return FALSE;
        }
        if ( !initDirect3D( ) )
        {
        return FALSE;
        }

        MoveWindow(hWnd,0,0,1280,960,true);
        ShowWindow(hWnd, nCmdShow);
        UpdateWindow(hWnd);

        return TRUE;
}

bool initDirect3D(void)
{
d3d_3D = NULL;
d3d_Device = NULL;

if( ! ( d3d_3D = Direct3DCreate9( D3D_SDK_VERSION ) ) )
{
return false;
}
    char str[20] = "";
    UINT va=d3d_3D->GetAdapterCount();
    sprintf(str,"X?%d    ",va);
    MessageBox(hWnd,str,"sdfd",NULL);
    D3DADAPTER_IDENTIFIER9 ident;
    d3d_3D->GetAdapterIdentifier(D3DADAPTER_DEFAULT, 0, &ident);
    MessageBox(hWnd,ident.Description,"sdfd",NULL);
    UINT numModes = d3d_3D->GetAdapterModeCount(D3DADAPTER_DEFAULT,D3DFMT_X8R8G8B8);
    sprintf(str,"X?%d    ",numModes);
        MessageBox(hWnd,str,"sdfd",NULL);
        for (UINT i=0; i < numModes; i++)
{
        D3DDISPLAYMODE mode;                                                               
        d3d_3D->EnumAdapterModes(D3DADAPTER_DEFAULT,D3DFMT_X8R8G8B8,i,&mode);                                                                             
        if ( mode.Width == SCREENWIDTH && mode.Height == SCREENHEIGHT )
        {               
        break ;
        }
}



D3DPRESENT_PARAMETERS d3dpp;
ZeroMemory( &d3dpp, sizeof( d3dpp ) );
d3dpp.Windowed = TRUE;
d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
d3dpp.BackBufferFormat = D3DFMT_UNKNOWN;
d3dpp.BackBufferCount = 1;
d3dpp.BackBufferHeight = 1280;
d3dpp.BackBufferWidth = 960;
d3dpp.hDeviceWindow = hWnd;

if( D3D_OK!=( d3d_3D->CreateDevice( D3DADAPTER_DEFAULT,
D3DDEVTYPE_REF,
hWnd,
D3DCREATE_SOFTWARE_VERTEXPROCESSING,
&d3dpp,
&d3d_Device ) ) )
{
return false;
}

if(D3D_OK!=(d3d_Device->CreateOffscreenPlainSurface(
1280,
960,
D3DFMT_X8R8G8B8,
D3DPOOL_DEFAULT,
&surface,
NULL))
)

{
  return NULL;
}


if(D3D_OK!=(D3DXLoadSurfaceFromFile( surface,
NULL,
NULL,
"Sophia2.bmp",
NULL,
D3DX_DEFAULT,
0,
NULL )))

return NULL;


return true;
}

void render(void)
{

if( NULL == d3d_Device ) return;

d3d_Device->Clear( 0, NULL, D3DCLEAR_TARGET,
D3DCOLOR_XRGB( 0,0,255), 1.0f, 0 );

if(SUCCEEDED(d3d_Device->BeginScene()))
{

IDirect3DSurface9* backbuffer = NULL;


d3d_Device->GetBackBuffer( 0,
0,
D3DBACKBUFFER_TYPE_MONO,
&backbuffer );
d3d_Device->StretchRect( surface,NULL,backbuffer,NULL,D3DTEXF_NONE );
if((d3d_Device->UpdateSurface(surface, NULL, backbuffer, NULL)))  
d3d_Device->EndScene();
}
d3d_Device-&gtresent( NULL, NULL, NULL, NULL );
}

void cleanUp (void)
{

if( d3d_Device != NULL )
d3d_Device->Release( );
if( d3d_3D != NULL )
d3d_3D->Release( );
if( surface != NULL )
surface->Release( );
}


LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
       
        switch (message)
        {       
                case WM_DESTROY:
                        PostQuitMessage(0);
                        break;
                default:
                        return DefWindowProc(hWnd, message, wParam, lParam);
   }
   return 0;
}

jk20012001

StretchRect里面把纹理过滤打开，把D3DTEXF_NONE换成D3DTEXF_LINEAR
PS：D3D里面不要随便操作BackBuffer，2D图片就用面片渲染到屏幕，或者直接用D3DXSPRITE