Direct3D轮回：游戏特效之风动、雾化

风动和雾化都是相对而言比较简单的游戏特效，实现起来甚至比我们前一节提到的晴天光晕还要简单~

大家还记得上上节中我们为陆地种植的那片植被吗？现在我们在场景中加入风的效果，让草儿动起来 ^ ^

首先，我们来实现一个风动效果的Shader：

D3DGame.cpp

/*-------------------------------------

代码清单：D3DGame.cpp
来自：http://www.cnblogs.com/kenkao

-------------------------------------*/

#include "StdAfx.h"
#include "D3DGame.h"
#include "D3DCamera.h"
#include "D3DEffect.h"
#include "CoordCross.h"
#include "SimpleXMesh.h"
#include "Texture2D.h"
#include "D3DSprite.h"
#include "Skybox.h"
#include "SpriteBatch.h"
#include "BaseTerrain.h"
#include "Water.h"
#include "PlantCollect.h"
#include "LensFlare.h"
#include "D3DFog.h"
#include <stdio.h>
#include <time.h>

//---通用全局变量

HINSTANCE g_hInst;
HWND g_hWnd;
D3DXMATRIX g_matWorld;
D3DXMATRIX g_matProjection;
D3DPRESENT_PARAMETERS g_D3DPP;

//---D3D全局变量

IDirect3D9 *g_pD3D = NULL;
IDirect3DDevice9 *g_pD3DDevice = NULL;
CMouseInput *g_pMouseInput = NULL;
CKeyboardInput *g_pKeyboardInput = NULL;
CD3DCamera *g_pD3DCamera = NULL;
CSpriteBatch *g_pSpriteBatch = NULL;
CSkybox *g_pSkybox = NULL;
CBaseTerrain *g_pBaseTerrain = NULL;
CWater *g_pWater = NULL;
CPlantCollect *g_pPlant = NULL;
CSimpleXMesh *g_pMesh = NULL;
CLensFlare *g_pFlare = NULL;

// 场景绘制
void DrawScene(bool isReflect,bool isRefract);

void Initialize(HINSTANCE hInst, HWND hWnd)
{
g_hInst = hInst;
g_hWnd = hWnd;
InitD3D(&g_pD3D, &g_pD3DDevice, g_D3DPP, g_matProjection, hWnd);
g_pMouseInput = new CMouseInput;
g_pMouseInput->Initialize(hInst,hWnd);
g_pKeyboardInput = new CKeyboardInput;
g_pKeyboardInput->Initialize(hInst,hWnd);
g_pD3DCamera = new CD3DCamera;
g_pSpriteBatch = new CSpriteBatch(g_pD3DDevice);
srand(time(0));
}

CTexture2D* debugTexture = NULL;

void LoadContent()
{
g_pD3DCamera->SetCameraPos(D3DXVECTOR3(600.0f,0.0f,600.0f));

g_pSkybox = new CSkybox;
g_pSkybox->Create("Skybox_0.JPG","Skybox_1.JPG","Skybox_2.JPG"
,"Skybox_3.JPG","Skybox_4.JPG","Skybox_5.JPG");

g_pBaseTerrain = new CBaseTerrain;
g_pBaseTerrain->Create(128,128,10,"HeightData_128x128.raw","Grass.dds");

g_pWater = new CWater;
g_pWater->Create(1280,1280,0.0f,0.0f,40.0f);

g_pPlant = new CPlantCollect;
g_pPlant->Create(60,90,15);

g_pMesh = new CSimpleXMesh;
g_pMesh->LoadXMesh("WindMill.x");

g_pFlare = new CLensFlare;
g_pFlare->Create(D3DXVECTOR3(-1600,700,600),D3DXVECTOR2(800,600));

ResetFog(D3DFOGTYPE_PIXEL,D3DFOG_EXP2,D3DXCOLOR_WHITE,0.001f);
}

void Update(float gameTick)
{
g_pMouseInput->GetState();
g_pKeyboardInput->GetState();

// 更新摄影机高度
D3DXVECTOR3 CameraPos = g_pD3DCamera->GetCameraPos();
float roleHeight = 25.0f;
float Ty = g_pBaseTerrain->GetExactHeightAt(CameraPos.x,CameraPos.z) + roleHeight;
g_pD3DCamera->SetCameraPos(D3DXVECTOR3(
CameraPos.x,
Ty,
CameraPos.z));

g_pD3DCamera->Update();
}

void Draw(float gameTick)
{
g_pD3DDevice->GetTransform(D3DTS_WORLD, &g_matWorld);
g_pD3DDevice->SetTransform(D3DTS_VIEW, &g_pD3DCamera->GetViewMatrix());
if(SUCCEEDED(g_pD3DDevice->BeginScene()))
{
BeginFog(g_pD3DDevice);

g_pWater->BeginReflect();
DrawScene(true,false);
g_pWater->EndReflect();

g_pWater->BeginRefract();
DrawScene(false,true);
g_pWater->EndRefract();

g_pD3DDevice->Clear(0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, D3DCOLOR_RGBA(100,149,237,255), 1.0f, 0);
DrawScene(false,false);
g_pWater->Draw(gameTick);
g_pPlant->Draw(gameTick);
g_pFlare->Draw();

EndFog(g_pD3DDevice);

g_pD3DDevice->EndScene();
}
g_pD3DDevice->Present(NULL, NULL, NULL, NULL);
}

void DrawScene(bool isReflect,bool isRefract)
{
g_pSkybox->Draw(isReflect,isRefract);
g_pBaseTerrain->Draw();

D3DXMATRIX scalTrans;
D3DXMatrixScaling(&scalTrans,5.0f,5.0f,5.0f);
D3DXMATRIX movTrans;
D3DXMatrixTranslation(&movTrans,366,g_pBaseTerrain->GetExactHeightAt(366,190)-5.0f,190);
g_pMesh->DrawXMesh(scalTrans * movTrans);
}

void UnloadContent()
{
ReleaseCOM(g_pFlare);
ReleaseCOM(g_pPlant);
ReleaseCOM(g_pWater);
ReleaseCOM(g_pBaseTerrain);
ReleaseCOM(g_pSkybox);
}

void Dispose()
{
ReleaseCOM(g_pSpriteBatch);
ReleaseCOM(g_pD3DCamera);
ReleaseCOM(g_pKeyboardInput);
ReleaseCOM(g_pMouseInput);
ReleaseCOM(g_pD3DDevice);
ReleaseCOM(g_pD3D);
}
最后是效果图：



配合合适的纹理，近处的景色与远处的天空完全浑然一体~

想到一句图形学领域的至理名言：Everything can be faked~ 不正是这样吗？呵呵~

以上，谢谢~