一个关于DirectX 变换的问题(进者有分)

2005-01-05 02:48:46 366 阅读 AI 写同款 · GEO 优化AI 选题数据监测一键分发 ›

DirectX投影变换矩阵的原理与推导，齐次裁剪空间的应用举例 DirectX Geometry Pipeline的投影变换不是D3DXMatrixShadow或者几何书上的投影变换。几何书上的投影变换是这样的：分别是平行投影和透视投影，把空间中的三维物体变成二维平面上的图形。而DirectX Geometry Pipeline的投影变换是这样的：上图分别是 Perspective Camera 和 Orthographic Camera 的视景体1 阅读详情

我下载了DirectX 9的SDK，安装完毕后在Microsoft DirectX 9.0 SDK (December 2004)\Samples\C++\Direct3D\Tutorials\Tut02_Vertices有一个如何绘制三角形的例子以及Tut03_Matrices如何设置变换矩阵。但是我看完第二个例子后，想直接在上面增加变换矩阵即
void SetMatrix()
{
HRESULT result;
D3DXMATRIXA16 matWorld;
D3DXMatrixTranslation(&matWorld, 50, 50, 0);

result = g_pd3dDevice->SetTransform(D3DTS_WORLD, &matWorld);
assert(result == D3D_OK);

D3DXMATRIXA16 matView;
D3DXVECTOR3 vEyePt(0, 0, 6);
D3DXVECTOR3 vLookatPt(0, 0, -5);
D3DXVECTOR3 vUpVec(0, 1, 0);
D3DXMatrixLookAtLH(&matView, &vEyePt, &vLookatPt, &vUpVec);

g_pd3dDevice->SetTransform(D3DTS_VIEW, &matView);

D3DXMATRIXA16 matProj;
D3DXMatrixPerspectiveFovLH( &matProj, D3DX_PI/4, 1.0f, 1.0f, 100.0f );
g_pd3dDevice->SetTransform( D3DTS_PROJECTION, &matProj );
}

在绘制函数里面加上了对SetMatrix的调用
VOID Render()
{
// Clear the backbuffer to a blue color
g_pd3dDevice->Clear( 0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0,0,255), 1.0f, 0 );

// Begin the scene
if( SUCCEEDED( g_pd3dDevice->BeginScene() ) )
{
SetMatrix();

g_pd3dDevice->SetStreamSource( 0, g_pVB, 0, sizeof(CUSTOMVERTEX) );
g_pd3dDevice->SetFVF( D3DFVF_CUSTOMVERTEX );
g_pd3dDevice->DrawPrimitive( D3DPT_TRIANGLEFAN, 0, 2);

// End the scene
g_pd3dDevice->EndScene();
}

// Present the backbuffer contents to the display
g_pd3dDevice->Present( NULL, NULL, NULL, NULL );
}

困扰我的就是不管我怎么设置这些变换矩阵，最终的显示结果都一样好像就没有设置过这些变换一样，我想请问大虾我哪里做错了或者少添加了什么东西？

...全文

Krylov子空间与Arnoldi过程一、应用背景 Krylov子空间方法是模型降阶(MOR)的一种，Krylov 子空间方法就是在Krylov子空间中寻找近似解。二、Krylov子空间 n是原始矩阵的维度，m为降阶后矩阵的维度，通常m<<n。三、Arnoldi 过程: 计算Km 的一组正交对应上述MGS过程的python代码： import numpy as np def arnoldi_itera... 阅读详情

ChinaShrimp

游戏开发 8,324 成员 23,685 内容

+ 关注 + 加入社区

切换为时间正序

ChinaShrimp 2005-09-03

打赏
举报

多谢大家

chijingde 2005-03-04

打赏
举报

应该解决了吧？

IO_X 2005-03-04

打赏
举报

关于RHW顶点格式的帖子见过N遍了...-.-b

bright_chn 2005-03-03

打赏
举报

up~

mars_snailbaby 2005-03-03

打赏
举报

看一下

tomwen 2005-03-03

打赏
举报

偶不是很懂
也来学学

Snow_1980 2005-01-12

打赏
举报

惭愧，我还不知道呢……

IO_X 2005-01-11

打赏
举报

晕，有rhw的顶点是不经过变换管道的

Leon8086 2005-01-11

打赏
举报

仔细看看Vertex Format那章，D3DFVF_XYZRHW这种格式属于“Lit & Transformed”的顶点，就是说在他上面不会再做光照和坐标系变换了。这种定点格式直接对应于RenderTarget上面的像素点。

Kshape 2005-01-09

打赏
举报

zhouxiaoxiao2015 2005-01-08

打赏
举报

该成这个试一试：D3DFVF_XYZ|D3DFVF_NORMAL|D3DFVF_TEX1

xiaolizi 2005-01-08

打赏
举报

#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZ|D3DFVF_DIFFUSE)
这个格式比较合适

lucky420 2005-01-08

打赏
举报

D3DFVF_XYZRHW：Vertex format includes the position of a transformed vertex.它把你设的位置值直接作为转换后的坐标，所以你的转换矩阵不起作用的。

寻开心 2005-01-07

打赏
举报

支持,iwaiwai的说法, 这种格式根本就不受变换矩阵的影响

小菲姐姐说 2005-01-07

打赏
举报

#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZRHW|D3DFVF_DIFFUSE)

D3DFVF_XYZRHW这个参数的意义查一查

ChinaShrimp 2005-01-06

打赏
举报

困扰我的就是不管我怎么设置这些变换矩阵，最终的显示结果都一样好像就没有设置过这些变换一样，我想请问大虾我哪里做错了或者少添加了什么东西？

潘李亮 2005-01-05

打赏
举报

你想问什么啊

ChinaShrimp 2005-01-05

打赏
举报

很着急，请大家多多帮忙！

ChinaShrimp 2005-01-05

打赏
举报

//-----------------------------------------------------------------------------
// Name: Cleanup()
// Desc: Releases all previously initialized objects
//-----------------------------------------------------------------------------
VOID Cleanup()
{
if( g_pVB != NULL )
g_pVB->Release();

if( g_pd3dDevice != NULL )
g_pd3dDevice->Release();

if( g_pD3D != NULL )
g_pD3D->Release();
}

void SetMatrix()
{
HRESULT result;
D3DXMATRIXA16 matWorld;
D3DXMatrixTranslation(&matWorld, 50, 50, 0);

result = g_pd3dDevice->SetTransform(D3DTS_WORLD, &matWorld);
assert(result == D3D_OK);

D3DXMATRIXA16 matView;
D3DXVECTOR3 vEyePt(0, 0, 6);
D3DXVECTOR3 vLookatPt(0, 0, -5);
D3DXVECTOR3 vUpVec(0, 1, 0);
D3DXMatrixLookAtLH(&matView, &vEyePt, &vLookatPt, &vUpVec);

g_pd3dDevice->SetTransform(D3DTS_VIEW, &matView);

D3DXMATRIXA16 matProj;
D3DXMatrixPerspectiveFovLH( &matProj, D3DX_PI/4, 1.0f, 1.0f, 100.0f );
g_pd3dDevice->SetTransform( D3DTS_PROJECTION, &matProj );
}

//-----------------------------------------------------------------------------
// Name: Render()
// Desc: Draws the scene
//-----------------------------------------------------------------------------
VOID Render()
{
// Clear the backbuffer to a blue color
g_pd3dDevice->Clear( 0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0,0,255), 1.0f, 0 );

// Begin the scene
if( SUCCEEDED( g_pd3dDevice->BeginScene() ) )
{
SetMatrix();
// Draw the triangles in the vertex buffer. This is broken into a few
// steps. We are passing the vertices down a "stream", so first we need
// to specify the source of that stream, which is our vertex buffer. Then
// we need to let D3D know what vertex shader to use. Full, custom vertex
// shaders are an advanced topic, but in most cases the vertex shader is
// just the FVF, so that D3D knows what type of vertices we are dealing
// with. Finally, we call DrawPrimitive() which does the actual rendering
// of our geometry (in this case, just one triangle).
g_pd3dDevice->SetStreamSource( 0, g_pVB, 0, sizeof(CUSTOMVERTEX) );
g_pd3dDevice->SetFVF( D3DFVF_CUSTOMVERTEX );
g_pd3dDevice->DrawPrimitive( D3DPT_TRIANGLEFAN, 0, 2);

// End the scene
g_pd3dDevice->EndScene();
}

// Present the backbuffer contents to the display
g_pd3dDevice->Present( NULL, NULL, NULL, NULL );
}

//-----------------------------------------------------------------------------
// Name: MsgProc()
// Desc: The window's message handler
//-----------------------------------------------------------------------------
LRESULT WINAPI MsgProc( HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam )
{
switch( msg )
{
case WM_DESTROY:
Cleanup();
PostQuitMessage( 0 );
return 0;
}

return DefWindowProc( hWnd, msg, wParam, lParam );
}

//-----------------------------------------------------------------------------
// Name: WinMain()
// Desc: The application's entry point
//-----------------------------------------------------------------------------
INT WINAPI WinMain( HINSTANCE hInst, HINSTANCE, LPSTR, INT )
{
// Register the window class
WNDCLASSEX wc = { sizeof(WNDCLASSEX), CS_CLASSDC, MsgProc, 0L, 0L,
GetModuleHandle(NULL), NULL, NULL, NULL, NULL,
"test", NULL };
RegisterClassEx( &wc );

// Create the application's window
HWND hWnd = CreateWindow( "test", "transform",
WS_OVERLAPPEDWINDOW, 100, 100, 512, 512,
GetDesktopWindow(), NULL, wc.hInstance, NULL );

// Initialize Direct3D
if( SUCCEEDED( InitD3D( hWnd ) ) )
{
// Create the vertex buffer
if( SUCCEEDED( InitVB() ) )
{
// Show the window
ShowWindow( hWnd, SW_SHOWDEFAULT );
UpdateWindow( hWnd );

// Enter the message loop
MSG msg;
ZeroMemory( &msg, sizeof(msg) );
while( msg.message!=WM_QUIT )
{
if( PeekMessage( &msg, NULL, 0U, 0U, PM_REMOVE ) )
{
TranslateMessage( &msg );
DispatchMessage( &msg );
}
else
Render();
}
}
}

UnregisterClass( "test", wc.hInstance );
return 0;
}

ChinaShrimp 2005-01-05

打赏
举报

多谢了！！！
全部代码：
#include <Windows.h>
#include <mmsystem.h>
#include <d3dx9.h>
#include <strsafe.h>
#include <assert.h>

//-----------------------------------------------------------------------------
// Global variables
//-----------------------------------------------------------------------------
LPDIRECT3D9 g_pD3D = NULL; // Used to create the D3DDevice
LPDIRECT3DDEVICE9 g_pd3dDevice = NULL; // Our rendering device
LPDIRECT3DVERTEXBUFFER9 g_pVB = NULL; // Buffer to hold vertices

// A structure for our custom vertex type
struct CUSTOMVERTEX
{
FLOAT x, y, z, rhw; // The transformed position for the vertex
DWORD color; // The vertex color
};

// Our custom FVF, which describes our custom vertex structure
#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZRHW|D3DFVF_DIFFUSE)

//-----------------------------------------------------------------------------
// Name: InitD3D()
// Desc: Initializes Direct3D
//-----------------------------------------------------------------------------
HRESULT InitD3D( HWND hWnd )
{
// Create the D3D object.
if( NULL == ( g_pD3D = Direct3DCreate9( D3D_SDK_VERSION ) ) )
return E_FAIL;

// Set up the structure used to create the D3DDevice
D3DPRESENT_PARAMETERS d3dpp;
ZeroMemory( &d3dpp, sizeof(d3dpp) );
d3dpp.Windowed = TRUE;
d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD;
d3dpp.BackBufferFormat = D3DFMT_UNKNOWN;

// Create the D3DDevice
if( FAILED( g_pD3D->CreateDevice( D3DADAPTER_DEFAULT, D3DDEVTYPE_HAL, hWnd,
D3DCREATE_SOFTWARE_VERTEXPROCESSING,
&d3dpp, &g_pd3dDevice ) ) )
{
return E_FAIL;
}

// Device state would normally be set here

return S_OK;
}

//-----------------------------------------------------------------------------
// Name: InitVB()
// Desc: Creates a vertex buffer and fills it with our vertices. The vertex
// buffer is basically just a chuck of memory that holds vertices. After
// creating it, we must Lock()/Unlock() it to fill it. For indices, D3D
// also uses index buffers. The special thing about vertex and index
// buffers is that they can be created in device memory, allowing some
// cards to process them in hardware, resulting in a dramatic
// performance gain.
//-----------------------------------------------------------------------------
HRESULT InitVB()
{
float fWidth = 2*128.0f;
// Initialize three vertices for rendering a triangle
CUSTOMVERTEX vertices[] =
{
{ -fWidth, -fWidth, 0.5f, 1.0f, 0xffff0000, }, // x, y, z, rhw, color
{ fWidth, -fWidth, 0.5f, 1.0f, 0xff00ff00, },
{ fWidth, fWidth, 0.5f, 1.0f, 0xff00ffff, },
{ -fWidth, fWidth, 0.5f, 1.0f, 0xff00ffff, }
};

// Create the vertex buffer. Here we are allocating enough memory
// (from the default pool) to hold all our 3 custom vertices. We also
// specify the FVF, so the vertex buffer knows what data it contains.
if( FAILED( g_pd3dDevice->CreateVertexBuffer( 4*sizeof(CUSTOMVERTEX),
0, D3DFVF_CUSTOMVERTEX,
D3DPOOL_DEFAULT, &g_pVB, NULL ) ) )
{
return E_FAIL;
}

// Now we fill the vertex buffer. To do this, we need to Lock() the VB to
// gain access to the vertices. This mechanism is required becuase vertex
// buffers may be in device memory.
VOID* pVertices;
if( FAILED( g_pVB->Lock( 0, sizeof(vertices), (void**)&pVertices, 0 ) ) )
return E_FAIL;
memcpy( pVertices, vertices, sizeof(vertices) );
g_pVB->Unlock();

return S_OK;
}

一个关于DirectX 变换的问题(进者有分)

相关推荐