经过四天的努力,终于自己实现了3D柏林噪声,当第一次用它成功渲染出茶壶的时候,感觉自己跟《当幸福来敲门》的男主角chris一样,当时不由自主为自己鼓起了掌.
4天时间啊,这4天时间基本上没有背单词,白天一个人去教室面对冰冷的代码.晚上回寝室熬夜到2,3点,到处在网上找资料,找源码,但是当自己把茶壶渲染出来的时候,突然觉得这一切都是值得的,因为它那斑驳的颜色温暖了我的心!!!
好了,转入正题.
其实它的原理并不是很难,但是由于网上实现的版本太多太杂,真要实现起来竟然不知从何处下手,而且自己写的时候会遇到各种各样的问题.最终写出来了,所以很欣然.
先看下,我在网上找的一些资料吧
另外我还下载了libnoise源码,可以说这个是我能成功渲染出茶壶的关键.后面我会提到.
好了,这里我只讲1到3D的柏林噪声,4D的我没有实现,实在没有时间,不能在这个环节浪费太多了时间,因为项目里面只用到了2D的柏林噪声来渲染海面.
由于网上理论资料也很详细,我这里主要讲解实现过程中需要注意的地方.
先简单提一下理论,
Perlin噪声由多个coherent noise组成，每一个coherent noise称为一个octave.
octave越多，Perlin噪声就越细致，但计算时间也越长。
具体理论知识见
http://blog.sina.com.cn/s/blog_68f6e8a901013t7d.html
http://www.cnblogs.com/babyrender/archive/2008/10/27/BabyRender.html
coherent 噪声函数
输入为对应维数的向量(对于一维来说就是一个float,对于二维来说就是一个float[2],以此类推)
输出为[-1,1]的float
现在拿一维来举例,首选我们需要在值为整数的点为其生成随机的梯度(1维下是斜率),然后找出输入的float数f左边和右边的两个整数x0,x1,然后找到x0,x1到的梯度g0,g1,算出点f到点x0和x1的向量r0 = f - x0, r1 = f - x1 = r0 - 1,最后分别将两个整数点的梯度与f到这两个整数点的向量相乘,得到u,v两个值,最后需要通过r0算出混合权值h,公式为
h = s_curve_new(r0),最后得到范围在[-1,1]的随机数 u + h * (v - u)
#define s_curve(t) ( t * t * (3. - 2. * t) ) //即3t^2 - 2t^3 ,旧版本
#define s_curve_new(t) ( t * t * t * (t * (t * 6 - 15) + 10) ) //即 6t^5 - 15t^4 + 10t^3,新版本
好了,下面就一个版本一个版本的讲吧
首先是两个官方版本:
http://mrl.nyu.edu/~perlin/noise
第一个版本,只实现了3D的coherent noise
下面是我自己的代码
/*------------------------------------------------------------
main.cpp -- http://mrl.nyu.edu/~perlin/noise/
(c) Seamanj.2013/9/6
------------------------------------------------------------*/
#include <iostream>
#include <cmath>
using namespace std;
int* p;
int permutation[] = { 151,160,137,91,90,15,
131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,
77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,
135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,
5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,
129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,
251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,
49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180
};
static double fade(double t) { return t * t * t * (t * (t * 6 - 15) + 10); }
static double lerp(double t, double a, double b) { return a + t * (b - a); }
static double grad(int hash, double x, double y, double z) //注意梯度产生[-1,1]的范围
{
int h = hash & 15; // CONVERT LO 4 BITS OF HASH CODE INTO 12 GRADIENT DIRECTIONS.
double u = h<8 ? x : y,v = h<4 ? y : h==12||h==14 ? x : z;
return ((h&1) == 0 ? u : -u) + ((h&2) == 0 ? v : -v);//+号左边有四种情况,右边有八种情况
}
double Noise3D(double x, double y, double z)//输出范围为[-1,1]
{
int iX = (int)floor(x) & 255,
iY = (int)floor(y) & 255,
iZ = (int)floor(z) & 255;
x -= floor(x);
y -= floor(y);
z -= floor(z);
double u = fade(x),
v = fade(y),
w = fade(z);
//index∈[0,511] p[index]∈[0,255] iX,iY,iZ ∈ [0,255]
int A = p[iX] + iY, AA = p[A] + iZ, AB = p[A+1] + iZ,
B = p[iX + 1] + iY, BA = p[B] + iZ, BB = p[B + 1] + iZ;
return lerp(w, lerp(v,
lerp(u, grad(p[AA], x, y, z), grad(p[BA], x - 1, y, z)),
lerp(u, grad(p[AB], x, y - 1, z), grad(p[BB], x - 1, y - 1, z))),
lerp(v,
lerp(u, grad(p[AA + 1], x, y, z - 1), grad(p[BA + 1], x - 1, y, z - 1)),
lerp(u, grad(p[AB + 1], x, y - 1, z - 1), grad(p[BB + 1], x - 1, y - 1, z - 1))));
}
int main()
{
p = new int[512];
for (int i=0; i < 256 ; i++)
p[256+i] = p[i] = permutation[i]; //这里搞成两个是因为后面插值的时候+1了,有可能加到256去了
for(double d1 = -10, d2 = -10, d3 = -10; d1 <= 10 && d2 <= 10 && d3 <= 10; d1 += 0.01, d2 += 0.01, d3 += 0.01)
cout << Noise3D(d1, d2, d3) << endl;
delete [] p;
return 0;
}
运行结果:
这个结果表面看上去能接受,但是要拿来真正渲染的时候就会出问题,所以我们需要对输入的数据进行处理,后面我会讲
第二个版本比较详细,实现了1到3D的noise
http://mrl.nyu.edu/~perlin/doc/oscar.html
下面我的代码
/*------------------------------------------------------------
main.cpp -- http://mrl.nyu.edu/~perlin/doc/oscar.html
(c) Seamanj.2013/9/6
------------------------------------------------------------*/
#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#define B 0x100 //256
#define BM 0xff //255
#define N 0x1000 //4096
#define NP 12 // 2^N
#define NM 0xfff
static int p[ B + B + 2];
static float g3[B + B + 2][3];
static float g2[B + B + 2][2];
static float g1[B + B +2];
static int start = 1;//是否需要初始化
static void init(void);
#define s_curve(t) ( t * t * (3. - 2. * t) )
#define s_curve_new(t) ( t * t * t * (t * (t * 6 - 15) + 10) )
#define lerp(t, a, b) ( a + t * (b - a) )
// b0为小于vec[i]的整数,b1为大于vec[i]的整数,r0为中间点到b0的符号距离(为正),r1为中间点到b1的符号距离(为负)
#define setup(i, b0, b1, r0, r1) \
t = vec[i] + N;\
b0 = ((int)t) & BM;\
b1 = (b0+1) & BM;\
r0 = t - (int)t;\
r1 = r0 - 1;
double noise1(double arg)//输出范围[-1,1]
{
int bx0, bx1;
float rx0, rx1, sx, t, u, v ,vec[1];
vec[0] = arg;
if(start)
{
start = 0;
init();
}
setup(0, bx0, bx1, rx0, rx1 );
sx = s_curve(rx0);//根据rx0算出混合权值,这里采用的是Hermit插值,老版本了
//新版的公式为:weight = t * t * t * ( t * ( t * 6 - 15 ) + 10 );
//sx = s_curve_new(rx0);
u = rx0 * g1[ p[ bx0 ] ];//扰动下bx0,让bx0处梯度更加随机些
v = rx1 * g1[ p[ bx1 ] ];
return lerp(sx, u, v);//最后进行插值
}
float noise2(float vec[2])//vec[0]为x,vec[1]为y
{
int bx0, bx1, by0, by1, b00, b10, b01, b11;
float rx0, rx1, ry0, ry1, *q, sx, sy, a, b, u, v, t;
register int i,j;
if( start )
{
start = 0;
init();
}
setup(0, bx0, bx1, rx0, rx1);
setup(1, by0, by1, ry0, ry1);
i = p[bx0];
j = p[bx1];
b00 = p[i+by0];//得到四个随机值
b10 = p[j+by0];
b01 = p[i+by1];
b11 = p[j+by1];
sx = s_curve(rx0);//算出混合权值
sy = s_curve(ry0);
#define at2(rx,ry) ( rx * q[0] + ry * q[1] )
// by1
// ↑
// ry1
// ↓
// bx0←rx0→⊕←rx1→bx1
// +y ↑
// ↑ ry0
// →+x ↓
// by0
q = g2[b00]; u = at2(rx0, ry0);//将(bx0,by0)处的梯度与中间点到该点的向量(rx0,ry0)相乘
q = g2[b10]; v = at2(rx1, ry0);//将(bx1,by0)处的梯度与中间点到该点的向量(rx1,ry0)相乘
a = lerp(sx, u, v);
q = g2[b01]; u = at2(rx0, ry1);//将(bx0,by1)处的梯度与中间点到该点的向量(rx0,ry1)相乘
q = g2[b11]; v = at2(rx1, ry1);//将(bx1,by1)处的梯度与中间点到该点的向量(rx1,ry1)相乘
b = lerp(sx, u, v);
return lerp(sy, a ,b);//进行双线性插值
}
float noise3(float vec[3])
{
int bx0, bx1, by0, by1, bz0, bz1, b00, b10, b01, b11;
float rx0, rx1, ry0, ry1, rz0, rz1, *q, sx, sy, sz, a, b, c, d, u, v, t;
register int i, j;
if (start)
{
start = 0;
init();
}
setup(0, bx0, bx1, rx0, rx1);
setup(1, by0, by1, ry0, ry1);
setup(2, bz0, bz1, rz0, rz1);
i = p[bx0];
j = p[bx1];
b00 = p[i + by0];
b10 = p[j + by0];
b01 = p[i + by1];
b11 = p[j + by1];//产生四个随机数,和bz0,bz1组合成8个随机数
sx = s_curve(rx0);
sy = s_curve(ry0);
sz = s_curve(rz0);
#define at3(rx, ry, rz) ( rx * q[0] + ry * q[1] + rz * q[2] )
// by1
// ↑
// 丨 bz1
// ry1 ↗
// 丨 rz1
// ↓↙
// bx0←rx0→⊕←rx1→bx1
// ↗↑
// rz0 丨
// +y +z ↙ ry0
// ↑↗ bz0 丨
// →+x ↓
// by0
q = g3[b00 + bz0]; u = at3(rx0, ry0, rz0);//将(bx0,by0,bz0)处的梯度与中间点到该点的向量(rx0,ry0,rz0)相乘
q = g3[b10 + bz0]; v = at3(rx1, ry0, rz0);//将(bx1,by0,bz0)处的梯度与中间点到该点的向量(rx1,ry0,rz0)相乘
a = lerp(sx, u, v);
q = g3[b01 + bz0]; u = at3(rx0, ry1, rz0);//将(bx0,by1,bz0)处的梯度与中间点到该点的向量(rx0,ry1,rz0)相乘
q = g3[b11 + bz0]; v = at3(rx1, ry1, rz0);//将(bx1,by1,bz0)处的梯度与中间点到该点的向量(rx1,ry1,rz0)相乘
b = lerp(sx, u, v);
c = lerp(sy, a, b);
q = g3[b00 + bz1]; u = at3(rx0, ry0, rz1);//将(bx0,by0,bz1)处的梯度与中间点到该点的向量(rx0,ry0,rz1)相乘
q = g3[b10 + bz1]; v = at3(rx1, ry0, rz1);//将(bx1,by0,bz1)处的梯度与中间点到该点的向量(rx1,ry0,rz1)相乘
a = lerp(sx, u, v);
q = g3[b01 + bz1]; u = at3(rx0, ry1, rz1);//将(bx0,by1,bz1)处的梯度与中间点到该点的向量(rx0,ry1,rz1)相乘
q = g3[b11 + bz1]; v = at3(rx1, ry1, rz1);//将(bx1,by1,bz1)处的梯度与中间点到该点的向量(rx1,ry1,rz1)相乘
b = lerp(sx, u, v);
d = lerp(sy, a, b);
return lerp(sz, c, d);//进行三次线性插值
}
static void normalize2(float v[2])
{
float s;
s = sqrt(v[0] * v[0] + v[1] * v[1]);
v[0] = v[0] / s;
v[1] = v[1] / s;
}
static void normalize3(float v[3])
{
float s;
s = sqrt(v[0] * v[0] + v[1] * v[1] + v[2] * v[2]);
v[0] = v[0] / s;
v[1] = v[1] / s;
v[2] = v[2] / s;
}
static void init(void)
{
int i, j, k;
for( i = 0; i < B; i++) // [0 , 255]
{
p[i] = i;
g1[i] = (float)((rand() % (B + B)) - B) / B;// [0 , 511] - 256 -> [-256 , 255] / 256 -> [-1 , 255/256 = 0.99609375]
for( j = 0; j < 2 ; j++)
g2[i][j] = (float)((rand() % (B + B)) - B) / B;//[-1 , 0.99609375]
normalize2(g2[i]);
for( j = 0; j < 3; j++)
g3[i][j] = (float)((rand() % (B + B )) - B) / B;//[-1 , 0.99609375]
normalize3(g3[i]);
}//为整数点生成随机的梯度
while( --i ) //[255,1]
{
k = p[i];
p[i] = p[ j = rand() % B];// j∈[0,255]
p[j] = k;
}//使p前256个数随机,数的范围为[0,255]
//注意p的范围为[0,513]
for( i = 0; i < B + 2; i++)//[0,257]
{
p[B + i] = p[i];// 0->256,1->257,...,255->511,256->512,257->513
//所以最后p[0~255]序列中为[0,255]的随机数,p[256~511]为p[0~255]的拷贝,p[512],p[513]为p[0],p[1]的拷贝
g1[B + i] = g1[i];
for( j = 0; j < 2; j++)
g2[B + 1][j] = g2[i][j];
for( j = 0; j < 3; j++)
g3[B + i][j] = g3[i][j];
//同理,将1~3维的随机梯度也按照上面的方法处理
}
}
int main()
{
// for(double d = -100.0; d < 100.0; d += 0.001)
// printf("%lf\n", noise1(d) );
// for(double d1 = -100.0,d2 = -100.0 ; d1 < 100 && d2 < 100 ; d1 += 0.001, d2 += 0.001)
// {
// float vec[2] = {d1,d2};
// printf("%lf\n", noise2(vec));
// }
for(double d1 = -100.0,d2 = -100.0,d3 = -100.0 ; d1 < 100 && d2 < 100 && d3 < 100 ; d1 += 0.001, d2 += 0.001, d3 += 0.001)
{
float vec[3] = {d1,d2,d3};
printf("%lf\n", noise3(vec));
}
}
输出结果:
看了一下输出结果,不是太理想,绝对值超过0.5的数几乎没有.哎,官方版本也坑啊!!!!!!尽管如此,我的茶壶例子还是基本这个版本的3D noise写的,谁叫它是官方版本呢,
但是我看了下libnoise的输出,0.6,0.7都很常见,以后估计我会用libnoise这个库
/*------------------------------------------------------------
main.cpp -- use libnoise to generate noise
(c) Seamanj.2013/9/6
------------------------------------------------------------*/
#include <iostream>
#include <noise.h>
#include "noiseutils.h"
using namespace noise;
#define lecture1 1
#define lecture2 0
int main (int argc, char** argv)
{
module::Perlin myModule;
#if lecture1
for(double d1 = -100.0,d2 = -100.0,d3 = -100.0 ; d1 < 100 && d2 < 100 && d3 < 100 ; d1 += 0.001, d2 += 0.001, d3 += 0.001)
{
std::cout << myModule.GetValue (d1,d2,d3) << std::endl;
}
#endif
#if lecture2
utils::NoiseMap heightMap;
utils::NoiseMapBuilderPlane heightMapBuilder;
heightMapBuilder.SetSourceModule (myModule);
heightMapBuilder.SetDestNoiseMap (heightMap);
heightMapBuilder.SetDestSize (256, 256);
heightMapBuilder.SetBounds (2.0, 6.0, 1.0, 5.0);
heightMapBuilder.Build ();
utils::RendererImage renderer;
utils::Image image;
renderer.SetSourceNoiseMap (heightMap);
renderer.SetDestImage (image);
renderer.Render ();
utils::WriterBMP writer;
writer.SetSourceImage (image);
writer.SetDestFilename ("tutorial.bmp");
writer.WriteDestFile ();
#endif
return 0;
}
另外,我根据<<三维游戏引擎设计技术及其应用>>这本书的提示生成了一个2D Perlin noise渲染了上面Displacement mapping讲过的海洋,只不过这里的移位贴图是我们通过2D Perlin noise生成的,不是预先设定的,虽然版本有点山寨,但是效果还是可以接受
它的倍频的采样方法有点特别,最低倍频,波长最长,振幅最大,如果我们需要生成129*129的2D图(它的方法最好采用2^n + 1的大小的图),最低倍频,我们设波长为32,那么我们就分别
在0,32,64,96,128处进行采样(也就是生成0到振幅的随机数),然后中间的进行以这些点进行插值,当为2倍频时,周期减少一倍为16,则在,0,16,32,48,64,80,96,112,128处进行采样,然后进行插值,注意采样时这里振幅也会减少一倍.后面的依次类推,最后将它们全部累加得到的就是2D的perlin noise
用这个版本渲染的海洋
用这个版本生成的海洋以及对应的位移贴图,颜色越白,海面越高
用这个版本生成 的2D Perlin noise(即移位贴图,只不过是两张Perlin noise按照某一权值比重进行累加后的结果)
下面给出这个DEMO的源代码
/*------------------------------------------------------------
3D_Math_2DPerlinNoise_ocean.cpp -- achieve perlin noise
(c) Seamanj.2013/9/4
------------------------------------------------------------*/
#include "DXUT.h"
#include "resource.h"
// phase1 : add camera
// phase2 : add sky box
// phase3 : add grid mesh
// phase4 : add FX
// phase5 : add perlin noise
// phase6 : add flat technique
#define phase1 1
#define phase2 1
#define phase3 1
#define phase4 1
#define phase5 1
#define phase6 1
#if phase1
#include "DXUTcamera.h"
CFirstPersonCamera g_Camera;
#endif
#if phase2
// Vertex Buffer
LPDIRECT3DVERTEXBUFFER9 g_pVB = NULL;
// Index Buffer
LPDIRECT3DINDEXBUFFER9 g_pIB = NULL;
PDIRECT3DCUBETEXTURE9 g_pCubeTex = 0;
#endif
#if phase3
#include <vector>
int g_iVerticesNumPerRow = 128 + 1;
int g_iVerticesNumPerCol = 128 + 1;
float g_fDeltaX = 0.25f;
float g_fDeltaZ = 0.25f;
const float EPSILON = 0.001f;
IDirect3DVertexDeclaration9* g_pVertexDecl;
ID3DXMesh* g_pMesh;
// The two normal maps to scroll.
IDirect3DTexture9* g_pNormalTex1;
IDirect3DTexture9* g_pNormalTex2;
// The two displacement maps to scroll.
IDirect3DTexture9* g_pDisplacementTex1;
IDirect3DTexture9* g_pDisplacementTex2;
//===============================================================
// Colors and Materials
const D3DXCOLOR WHITE(1.0f, 1.0f, 1.0f, 1.0f);
const D3DXCOLOR BLACK(0.0f, 0.0f, 0.0f, 1.0f);
const D3DXCOLOR RED(1.0f, 0.0f, 0.0f, 1.0f);
const D3DXCOLOR GREEN(0.0f, 1.0f, 0.0f, 1.0f);
const D3DXCOLOR BLUE(0.0f, 0.0f, 1.0f, 1.0f);
struct DirectionalLight
{
D3DXCOLOR ambient;
D3DXCOLOR diffuse;
D3DXCOLOR specular;
D3DXVECTOR3 directionInWorld;
};
struct Material
{
Material()
:ambient(WHITE), diffuse(WHITE), specular(WHITE), specularPower(8.0f){}
Material(const D3DXCOLOR& a, const D3DXCOLOR& d,
const D3DXCOLOR& s, float power)
:ambient(a), diffuse(d), specular(s), specularPower(power){}
D3DXCOLOR ambient;
D3DXCOLOR diffuse;
D3DXCOLOR specular;
float specularPower;
};
DirectionalLight g_structDirectionalLight;
Material g_structMaterial;
D3DXVECTOR2 g_scaleHeights = D3DXVECTOR2(0.5f, 0.5f);
float g_fTexScale = 8.0f;
D3DXVECTOR2 g_normalMapVelocity1 = D3DXVECTOR2(0.05f, 0.07f);
D3DXVECTOR2 g_normalMapVelocity2 = D3DXVECTOR2(-0.01f, 0.13f);
D3DXVECTOR2 g_displacementMapVelocity1 = D3DXVECTOR2(0.012f, 0.015f);
D3DXVECTOR2 g_displacementMapVelocity2 = D3DXVECTOR2(0.014f, 0.05f);
// Offset of normal maps for scrolling (vary as a function of time)
D3DXVECTOR2 g_normalMapOffset1(0.0f, 0.0f);
D3DXVECTOR2 g_normalMapOffset2(0.0f, 0.0f);
// Offset of displacement maps for scrolling (vary as a function of time)
D3DXVECTOR2 g_displacementMapOffset1(0.0f, 0.0f);
D3DXVECTOR2 g_displacementMapOffset2(0.0f, 0.0f);
#endif
#if phase4
#include "SDKmisc.h"//加载文件时会用到
ID3DXEffect* g_pEffect = NULL; // D3DX effect interface
D3DXHANDLE g_hTech = 0;
#if phase6
D3DXHANDLE g_hFlatTech = 0;
#endif
D3DXHANDLE g_hWorld = 0;
D3DXHANDLE g_hWorldInv = 0;
D3DXHANDLE g_hWorldViewProj = 0;
D3DXHANDLE g_hEyePositionInWorld = 0;
D3DXHANDLE g_hDirectionalLightStruct = 0;
D3DXHANDLE g_hMaterialStruct = 0;
D3DXHANDLE g_hNormalTex1 = 0;
D3DXHANDLE g_hNormalTex2 = 0;
D3DXHANDLE g_hDisplacementTex1 = 0;
D3DXHANDLE g_hDisplacementTex2 = 0;
D3DXHANDLE g_hNormalOffset1 = 0;
D3DXHANDLE g_hNormalOffset2 = 0;
D3DXHANDLE g_hDisplacementOffset1 = 0;
D3DXHANDLE g_hDisplacementOffset2 = 0;
D3DXHANDLE g_hScaleHeights = 0; //缩放移位1,2纹理得到的高度
D3DXHANDLE g_hDelta = 0; //网格X,Z轴方向的步长
#endif
#if phase5
#include "Perlin2D.h"
Perlin2D myPerlinNoise(4, 32, 256, 0.5);
#endif
//--------------------------------------------------------------------------------------
// Rejects any D3D9 devices that aren't acceptable to the app by returning false
//--------------------------------------------------------------------------------------
bool CALLBACK IsD3D9DeviceAcceptable( D3DCAPS9* pCaps, D3DFORMAT AdapterFormat, D3DFORMAT BackBufferFormat,
bool bWindowed, void* pUserContext )
{
// Typically want to skip back buffer formats that don't support alpha blending
IDirect3D9* pD3D = DXUTGetD3D9Object();
if( FAILED( pD3D->CheckDeviceFormat( pCaps->AdapterOrdinal, pCaps->DeviceType,
AdapterFormat, D3DUSAGE_QUERY_POSTPIXELSHADER_BLENDING,
D3DRTYPE_TEXTURE, BackBufferFormat ) ) )
return false;
return true;
}
//--------------------------------------------------------------------------------------
// Before a device is created, modify the device settings as needed
//--------------------------------------------------------------------------------------
bool CALLBACK ModifyDeviceSettings( DXUTDeviceSettings* pDeviceSettings, void* pUserContext )
{
#if phase1
pDeviceSettings->d3d9.pp.PresentationInterval = D3DPRESENT_INTERVAL_IMMEDIATE;
#endif
return true;
}
#if phase3
//create Vertex Declaration
HRESULT createVertexDeclaration( IDirect3DDevice9* pd3dDevice )
{
D3DVERTEXELEMENT9 decl[] =
{
// offsets in bytes
{0, 0, D3DDECLTYPE_FLOAT3, D3DDECLMETHOD_DEFAULT, D3DDECLUSAGE_POSITION, 0},
{0, 12, D3DDECLTYPE_FLOAT2, D3DDECLMETHOD_DEFAULT, D3DDECLUSAGE_TEXCOORD, 0},
{0, 20, D3DDECLTYPE_FLOAT2, D3DDECLMETHOD_DEFAULT, D3DDECLUSAGE_TEXCOORD, 1},
D3DDECL_END()
};
return pd3dDevice->CreateVertexDeclaration(decl, &g_pVertexDecl);
}
struct GridVertexFormat
{
D3DXVECTOR3 pos;
D3DXVECTOR2 scaledTexCoord; // [a, b]
D3DXVECTOR2 normalizedTexCoord; // [0, 1]
};
//将顶点位置以及索引写入指定的vector中,为后面写入缓冲区打下基础
void writeVertexPosAndIndicesToVectors(int iVerticesNumPerRow, int iVerticesNumPerCol,float fDeltaX, float fDeltaZ,
const D3DXVECTOR3& center,std::vector<D3DXVECTOR3>& vecVertexPosData,
std::vector<DWORD>& vecIndexData)
{
int iVerticesNum = iVerticesNumPerRow * iVerticesNumPerCol;
int iCellsNumPerRow = iVerticesNumPerRow - 1;
int iCellsNumPerCol = iVerticesNumPerCol - 1;
int iTrianglesNum = iCellsNumPerRow * iCellsNumPerCol * 2;
float fWidth = (float)iCellsNumPerCol * fDeltaX;
float fDepth = (float)iCellsNumPerRow * fDeltaZ;
//===========================================
// Build vertices.
// We first build the grid geometry centered about the origin and on
// the xz-plane, row-by-row and in a top-down fashion. We then translate
// the grid vertices so that they are centered about the specified
// parameter 'center'.从左上角开始,列序优先的方式放置顶点数据
vecVertexPosData.resize( iVerticesNum );
// Offsets to translate grid from quadrant 4 to center of
// coordinate system.
float fOffsetX = -fWidth * 0.5f;
float fOffsetZ = fDepth * 0.5f;
int k = 0;
for(float i = 0; i < iVerticesNumPerRow; ++i)
{
for(float j = 0; j < iVerticesNumPerCol; ++j)
{
// Negate the depth coordinate to put in quadrant four.
// Then offset to center about coordinate system.
vecVertexPosData[k].x = j * fDeltaX + fOffsetX;
vecVertexPosData[k].z = -i * fDeltaZ + fOffsetZ;
vecVertexPosData[k].y = 0.0f;
// Translate so that the center of the grid is at the
// specified 'center' parameter.
D3DXMATRIX T;
D3DXMatrixTranslation(&T, center.x, center.y, center.z);
D3DXVec3TransformCoord(&vecVertexPosData[k], &vecVertexPosData[k], &T);
++k; // Next vertex
}
}
//===========================================
// Build indices.
vecIndexData.resize(iTrianglesNum * 3);
// Generate indices for each quad.
k = 0;
for(DWORD i = 0; i < (DWORD)iCellsNumPerRow; ++i)
{
DWORD j;
for(j = 0; j < (DWORD)iCellsNumPerCol; ++j)
{
vecIndexData[k] = i * iVerticesNumPerCol + j;
vecIndexData[k + 1] = i * iVerticesNumPerCol + j + 1;
vecIndexData[k + 2] = (i+1) * iVerticesNumPerCol + j;
vecIndexData[k + 3] = (i+1) * iVerticesNumPerCol + j;
vecIndexData[k + 4] = i * iVerticesNumPerCol + j + 1;
vecIndexData[k + 5] = (i+1) * iVerticesNumPerCol + j + 1;
// 1---2 5
// | / / |
// | / / |
// 3 4---6
// next quad
k += 6;
}
// vecIndexData[k] = i * iVerticesNumPerCol + j;
// vecIndexData[k + 1] = i * iVerticesNumPerCol ;
// vecIndexData[k + 2] = (i+1) * iVerticesNumPerCol + j;
//
// vecIndexData[k + 3] = (i+1) * iVerticesNumPerCol + j;
// vecIndexData[k + 4] = i * iVerticesNumPerCol ;
// vecIndexData[k + 5] = (i+1) * iVerticesNumPerCol ;
// k += 6;
}
}
#endif
//--------------------------------------------------------------------------------------
// Create any D3D9 resources that will live through a device reset (D3DPOOL_MANAGED)
// and aren't tied to the back buffer size
//--------------------------------------------------------------------------------------
HRESULT CALLBACK OnD3D9CreateDevice( IDirect3DDevice9* pd3dDevice, const D3DSURFACE_DESC* pBackBufferSurfaceDesc,
void* pUserContext )
{
#if phase3
HRESULT hr;
#endif
#if phase1
// Setup the camera's view parameters
D3DXVECTOR3 vecEye( 0.0f, 0.0f, -5.0f );
D3DXVECTOR3 vecAt ( 0.0f, 0.0f, -0.0f );
g_Camera.SetViewParams( &vecEye, &vecAt );
g_Camera.SetEnablePositionMovement( true );
#endif
#if phase2
D3DXCreateCubeTextureFromFile(pd3dDevice, L"grassenvmap1024.dds", &g_pCubeTex);
#endif
#if phase3
createVertexDeclaration(pd3dDevice);
DWORD dwTrianglesNum = (g_iVerticesNumPerRow - 1) * (g_iVerticesNumPerCol - 1) * 2;
DWORD dwVerticesNum = g_iVerticesNumPerRow * g_iVerticesNumPerCol;
D3DVERTEXELEMENT9 elems[MAX_FVF_DECL_SIZE];
UINT uElemsNum = 0;
g_pVertexDecl->GetDeclaration(elems, &uElemsNum);
V( D3DXCreateMesh(dwTrianglesNum, dwVerticesNum, D3DXMESH_MANAGED, elems, pd3dDevice, &g_pMesh) );
//===============================================================
// Write the grid vertices and triangles to the mesh.
GridVertexFormat *pVertices = NULL;
V( g_pMesh->LockVertexBuffer(0, (void**)&pVertices) );
std::vector<D3DXVECTOR3> vecVertexPosData;
std::vector<DWORD> vecIndexData;
writeVertexPosAndIndicesToVectors(g_iVerticesNumPerRow, g_iVerticesNumPerCol, g_fDeltaX,
g_fDeltaZ, D3DXVECTOR3(0.0f, 0.0f, 0.0f), vecVertexPosData, vecIndexData);
for(int i = 0; i < g_iVerticesNumPerRow; ++i)
{
for(int j = 0; j < g_iVerticesNumPerCol; ++j)
{
DWORD index = i * g_iVerticesNumPerCol + j;
pVertices[index].pos = vecVertexPosData[index];
pVertices[index].scaledTexCoord = D3DXVECTOR2((float)j / (g_iVerticesNumPerCol-1),
(float)i / (g_iVerticesNumPerRow-1))* g_fTexScale;
//g_fTexScale表示Grid里面用几个纹理,值越大表示纹理重复次数越多
pVertices[index].normalizedTexCoord = D3DXVECTOR2((float)j / (g_iVerticesNumPerCol-1),
(float)i / (g_iVerticesNumPerRow-1));
}
}
V( g_pMesh->UnlockVertexBuffer() );
//===============================================================
// Write triangle data(Indices & Attributes) so we can compute normals.
WORD* pIndices = NULL;
V( g_pMesh->LockIndexBuffer(0, (void**)&pIndices) );
DWORD* pAttributes = NULL;
V( g_pMesh->LockAttributeBuffer(0, &pAttributes) );
for(UINT i = 0; i < g_pMesh->GetNumFaces(); ++i)
{
pIndices[i*3+0] = (WORD)vecIndexData[i*3+0];
pIndices[i*3+1] = (WORD)vecIndexData[i*3+1];
pIndices[i*3+2] = (WORD)vecIndexData[i*3+2];
pAttributes[i] = 0; // All in subset 0.
}
V( g_pMesh->UnlockIndexBuffer() );
V( g_pMesh->UnlockAttributeBuffer() );
//===============================================================
// Optimize for the vertex cache and build attribute table.
// D3DXMESHOPT_ATTRSORT optimization builds an attribute table.
DWORD* adj = new DWORD[g_pMesh->GetNumFaces() * 3];
// Generate adjacency info
V(g_pMesh->GenerateAdjacency(EPSILON, adj));
V(g_pMesh->OptimizeInplace(D3DXMESHOPT_VERTEXCACHE|D3DXMESHOPT_ATTRSORT,adj, 0, 0, 0));
delete[] adj;
//===============================================================
// Create textures.
V(D3DXCreateTextureFromFile(pd3dDevice, L"normal_map1.dds", &g_pNormalTex1));
V(D3DXCreateTextureFromFile(pd3dDevice, L"normal_map2.dds", &g_pNormalTex2));
#if !phase5
V(D3DXCreateTextureFromFileEx(pd3dDevice, L"Mytex1.jpg", g_iVerticesNumPerRow,
g_iVerticesNumPerCol,1, 0, D3DFMT_R32F, D3DPOOL_MANAGED, D3DX_DEFAULT, D3DX_DEFAULT,
0, 0, 0, &g_pDisplacementTex1));
V(D3DXCreateTextureFromFileEx(pd3dDevice, L"Mytex2.jpg", g_iVerticesNumPerRow,
g_iVerticesNumPerCol,1, 0, D3DFMT_R32F, D3DPOOL_MANAGED, D3DX_DEFAULT, D3DX_DEFAULT,
0, 0, 0, &g_pDisplacementTex2));
#else
//这里通过perlin noise来生成随机的高度值
V( D3DXCreateTexture(pd3dDevice, g_iVerticesNumPerCol, g_iVerticesNumPerRow, 0,
0, D3DFMT_R32F, D3DPOOL_MANAGED, &g_pDisplacementTex1) );
V( D3DXCreateTexture(pd3dDevice, g_iVerticesNumPerCol, g_iVerticesNumPerRow, 0,
0, D3DFMT_R32F, D3DPOOL_MANAGED, &g_pDisplacementTex2) );
D3DLOCKED_RECT lockedRect1,lockedRect2;
g_pDisplacementTex1->LockRect(0, &lockedRect1, 0, 0);
float* imageData1 = static_cast<float*>(lockedRect1.pBits);
g_pDisplacementTex2->LockRect(0, &lockedRect2, 0, 0);
float* imageData2 = static_cast<float*>(lockedRect2.pBits);
myPerlinNoise.CopyPerlin2DToBuffer(g_iVerticesNumPerCol, g_iVerticesNumPerRow, imageData1);
myPerlinNoise.CopyPerlin2DToBuffer(g_iVerticesNumPerCol, g_iVerticesNumPerRow, imageData2);
g_pDisplacementTex1->UnlockRect(0);
g_pDisplacementTex2->UnlockRect(0);
// fill mipmaps
//尼玛这里太帅了,必须要填充mipmap,创建的时候虽然创建了mipmap,但是没有填充,视角一旦太斜,就会出现
//黑色,原因就是因为高层的mipmap是黑色,啊啊啊,尼玛这地方又花了3个小时啊!!!!!!!!!!!!!
V( D3DXFilterTexture(
g_pDisplacementTex1,// texture to fill mipmap levels
0, // default palette
0, // use top level as source for lower levels
D3DX_DEFAULT)); // default filter
V( D3DXFilterTexture(g_pDisplacementTex2,0, 0, D3DX_DEFAULT));
// D3DSURFACE_DESC dd1,dd2;
// g_pDisplacementTex1->GetLevelDesc(0,&dd1);
// g_pDisplacementTex1->GetLevelDesc(0,&dd2);
//D3DXSaveTextureToFile(L"Mytex2.jpg", D3DXIFF_JPG,g_pDisplacementTex2,NULL);
#endif
#endif
#if phase4
WCHAR str[MAX_PATH];
// Read the D3DX effect file
V_RETURN( DXUTFindDXSDKMediaFileCch( str, MAX_PATH, L"PerlinNoise.fx" ) );
// Create the effect
LPD3DXBUFFER pErrorBuff = NULL;
V_RETURN( D3DXCreateEffectFromFile(
pd3dDevice, // associated device
str, // effect filename
NULL, // no preprocessor definitions
NULL, // no ID3DXInclude interface
D3DXSHADER_DEBUG, // compile flags
NULL, // don't share parameters
&g_pEffect, // return effect
&pErrorBuff // return error messages
) );
if( pErrorBuff )
MessageBoxA(0, (char*)pErrorBuff->GetBufferPointer(), 0, 0);
// get handle
g_hTech = g_pEffect->GetTechniqueByName("myTech");
#if phase6
g_hFlatTech = g_pEffect->GetTechniqueByName("flatTech");
#endif
g_hWorld = g_pEffect->GetParameterByName(0, "g_mWorld");
g_hWorldInv = g_pEffect->GetParameterByName(0, "g_mWorldInv");
g_hWorldViewProj = g_pEffect->GetParameterByName(0, "g_mWorldViewProj");
g_hEyePositionInWorld = g_pEffect->GetParameterByName(0, "g_eyePositionInWorld");
g_hDirectionalLightStruct = g_pEffect->GetParameterByName(0, "g_structDirectionalLight");
g_hMaterialStruct = g_pEffect->GetParameterByName(0, "g_structMaterial");
g_hNormalTex1 = g_pEffect->GetParameterByName(0, "g_texNormalMap1");
g_hNormalTex2 = g_pEffect->GetParameterByName(0, "g_texNormalMap2");
g_hDisplacementTex1 = g_pEffect->GetParameterByName(0, "g_texDisplacementMap1");
g_hDisplacementTex2 = g_pEffect->GetParameterByName(0, "g_texDisplacementMap2");
g_hNormalOffset1 = g_pEffect->GetParameterByName(0, "g_normalOffset1");
g_hNormalOffset2 = g_pEffect->GetParameterByName(0, "g_normalOffset2");
g_hDisplacementOffset1 = g_pEffect->GetParameterByName(0, "g_DisplacementOffset1");
g_hDisplacementOffset2 = g_pEffect->GetParameterByName(0, "g_DisplacementOffset2");
g_hScaleHeights = g_pEffect->GetParameterByName(0, "g_scaleHeights");
g_hDelta = g_pEffect->GetParameterByName(0, "g_delta");
// We don't need to set these every frame since they do not change.
D3DXMATRIXA16 mWorld, mWorldInv;
D3DXMatrixIdentity(&mWorld);
V(g_pEffect->SetMatrix(g_hWorld, &mWorld));
D3DXMatrixInverse(&mWorldInv, 0, &mWorld);
V(g_pEffect->SetMatrix(g_hWorldInv, &mWorldInv));
V(g_pEffect->SetTexture(g_hNormalTex1, g_pNormalTex1));
V(g_pEffect->SetTexture(g_hNormalTex2, g_pNormalTex2));
V(g_pEffect->SetTexture(g_hDisplacementTex1, g_pDisplacementTex1));
V(g_pEffect->SetTexture(g_hDisplacementTex2, g_pDisplacementTex2));
g_structDirectionalLight.directionInWorld = D3DXVECTOR3(0.0f, -1.0f, -3.0f);
D3DXVec3Normalize(&g_structDirectionalLight.directionInWorld, &g_structDirectionalLight.directionInWorld);
g_structDirectionalLight.ambient = D3DXCOLOR(0.3f, 0.3f, 0.3f, 1.0f);
g_structDirectionalLight.diffuse = D3DXCOLOR(1.0f, 1.0f, 1.0f, 1.0f);
g_structDirectionalLight.specular = D3DXCOLOR(0.7f, 0.7f, 0.7f, 1.0f);
V(g_pEffect->SetValue(g_hDirectionalLightStruct, &g_structDirectionalLight, sizeof(DirectionalLight)));
g_structMaterial.ambient = D3DXCOLOR(0.4f, 0.4f, 0.7f, 0.0f);
g_structMaterial.diffuse = D3DXCOLOR(0.4f, 0.4f, 0.7f, 1.0f);
g_structMaterial.specular = 0.8f*WHITE;
g_structMaterial.specularPower = 128.0f;
V(g_pEffect->SetValue(g_hMaterialStruct, &g_structMaterial, sizeof(Material)));
V(g_pEffect->SetValue(g_hScaleHeights, &g_scaleHeights, sizeof(D3DXVECTOR2)));
D3DXVECTOR2 delta(g_fDeltaX, g_fDeltaZ);
V(g_pEffect->SetValue(g_hDelta, &delta, sizeof(D3DXVECTOR2)));
#endif
return S_OK;
}
#if phase2
struct MyVertexFormat
{
FLOAT x, y, z;
FLOAT u, v, w;
};
#define FVF_VERTEX (D3DFVF_XYZ | D3DFVF_TEX1 | D3DFVF_TEXCOORDSIZE3(0) )
static HRESULT initVertexIndexBuffer(IDirect3DDevice9* pd3dDevice)
{
static const MyVertexFormat Vertices[] =
{
//+X
{ 1, -1, -1, 1, -1, -1 },
{ 1, -1, 1, 1, -1, 1 },
{ 1, 1, 1 , 1, 1, 1 },
{ 1, 1, -1, 1, 1, -1 },
//-X
{ -1, -1, -1,-1, -1, -1 },
{ -1, 1, -1, -1, 1, -1 },
{ -1, 1, 1 , -1, 1, 1 },
{ -1, -1, 1, -1, -1, 1},
//+Y
{ -1, 1, -1 ,-1, 1, -1 },
{ 1, 1, -1 ,1, 1, -1 },
{ 1, 1, 1 ,1, 1, 1},
{ -1, 1, 1 ,-1, 1, 1 },
//-Y
{ -1, -1, -1,-1, -1, -1 },
{ -1, -1, 1,-1, -1, 1 },
{ 1, -1, 1,1, -1, 1 },
{ 1, -1, -1, 1, -1, -1},
//Z
{ -1, -1, 1,-1, -1, 1 },
{ -1, 1, 1,-1, 1, 1 },
{ 1, 1, 1,1, 1, 1 },
{ 1, -1, 1,1, -1, 1 },
//-Z
{ -1, -1, -1,-1, -1, -1 },
{ 1, -1, -1,1, -1, -1 },
{ 1, 1, -1,1, 1, -1 },
{ -1, 1, -1,-1, 1, -1 }
};
if (FAILED(pd3dDevice->CreateVertexBuffer(sizeof(Vertices),
0, FVF_VERTEX,
D3DPOOL_DEFAULT,
&g_pVB, NULL))) {
return E_FAIL;
}
void* pVertices;
if (FAILED(g_pVB->Lock(0, 0, /* map entire buffer */
&pVertices, 0))) {
return E_FAIL;
}
memcpy(pVertices, Vertices, sizeof(Vertices));
g_pVB->Unlock();
// Create and initialize index buffer
static const WORD Indices[] =
{
0, 1, 2,
0, 2, 3,
4, 5, 6,
4, 6, 7,
8, 9, 10,
8,10, 11,
12,13,14,
12,14,15,
16,17,18,
16,18,19,
20,21,22,
20,22,23
};
if (FAILED(pd3dDevice->CreateIndexBuffer(sizeof(Indices),
D3DUSAGE_WRITEONLY,
D3DFMT_INDEX16,
D3DPOOL_DEFAULT,
&g_pIB, NULL))) {
return E_FAIL;
}
void* pIndices;
if (FAILED(g_pIB->Lock(0, 0, /* map entire buffer */
&pIndices, 0))) {
return E_FAIL;
}
memcpy(pIndices, Indices, sizeof(Indices));
g_pIB->Unlock();
return S_OK;
}
#endif
//--------------------------------------------------------------------------------------
// Create any D3D9 resources that won't live through a device reset (D3DPOOL_DEFAULT)
// or that are tied to the back buffer size
//--------------------------------------------------------------------------------------
HRESULT CALLBACK OnD3D9ResetDevice( IDirect3DDevice9* pd3dDevice, const D3DSURFACE_DESC* pBackBufferSurfaceDesc,
void* pUserContext )
{
#if phase1
pd3dDevice->SetRenderState( D3DRS_CULLMODE, D3DCULL_NONE );
//关闭光照处理, 默认情况下启用光照处理
pd3dDevice->SetRenderState( D3DRS_LIGHTING, FALSE );
//Setup the camera's projection parameters
float fAspectRatio = pBackBufferSurfaceDesc->Width / ( FLOAT )pBackBufferSurfaceDesc->Height;
g_Camera.SetProjParams( D3DX_PI / 2, fAspectRatio, 0.1f, 5000.0f );
#endif
#if phase4
#if phase3
HRESULT hr;
if( g_pEffect )
V_RETURN( g_pEffect->OnResetDevice() );
#endif
#endif
#if !phase2
return S_OK;
#else
return initVertexIndexBuffer(pd3dDevice);
#endif
}
//--------------------------------------------------------------------------------------
// Handle updates to the scene. This is called regardless of which D3D API is used
//--------------------------------------------------------------------------------------
void CALLBACK OnFrameMove( double fTime, float fElapsedTime, void* pUserContext )
{
#if phase1
g_Camera.FrameMove( fElapsedTime );
#endif
#if phase4
g_normalMapOffset1 += g_normalMapVelocity1 * fElapsedTime;
g_normalMapOffset2 += g_normalMapVelocity2 * fElapsedTime;
g_displacementMapOffset1 += g_displacementMapVelocity1 * fElapsedTime;
g_displacementMapOffset2 += g_displacementMapVelocity2 * fElapsedTime;
// if(g_normalMapOffset1.x >= 1.0f || g_normalMapOffset1.x <= -1.0f)
// g_normalMapOffset1.x = 0.0f;
// if(g_normalMapOffset2.x >= 1.0f || g_normalMapOffset2.x <= -1.0f)
// g_normalMapOffset2.x = 0.0f;
// if(g_normalMapOffset1.y >= 1.0f || g_normalMapOffset1.y <= -1.0f)
// g_normalMapOffset1.y = 0.0f;
// if(g_normalMapOffset2.y >= 1.0f || g_normalMapOffset2.y <= -1.0f)
// g_normalMapOffset2.y = 0.0f;
//
// if(g_displacementMapOffset1.x >= 1.0f || g_displacementMapOffset1.x <= -1.0f)
// g_displacementMapOffset1.x = 0.0f;
// if(g_displacementMapOffset2.x >= 1.0f || g_displacementMapOffset2.x <= -1.0f)
// g_displacementMapOffset2.x = 0.0f;
// if(g_displacementMapOffset1.y >= 1.0f || g_displacementMapOffset1.y <= -1.0f)
// g_displacementMapOffset1.y = 0.0f;
// if(g_displacementMapOffset2.y >= 1.0f || g_displacementMapOffset2.y <= -1.0f)
// g_displacementMapOffset2.y = 0.0f;
//注意这里不应该是以1来为单位,应该为2,因为是纹理是MIRROR方式,我就懒一下,不改了
#endif
}
//--------------------------------------------------------------------------------------
// Render the scene using the D3D9 device
//--------------------------------------------------------------------------------------
void CALLBACK OnD3D9FrameRender( IDirect3DDevice9* pd3dDevice, double fTime, float fElapsedTime, void* pUserContext )
{
HRESULT hr;
// Clear the render target and the zbuffer
V( pd3dDevice->Clear( 0, NULL, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, D3DCOLOR_ARGB( 0, 45, 50, 170 ), 1.0f, 0 ) );
// Render the scene
if( SUCCEEDED( pd3dDevice->BeginScene() ) )
{
#if phase2
pd3dDevice->SetRenderState(D3DRS_LIGHTING, false);
// Set world matrix
D3DXMATRIX M;
D3DXMatrixIdentity( &M ); // M = identity matrix
D3DXMatrixScaling(&M,2000, 2000, 2000);
pd3dDevice->SetTransform(D3DTS_WORLD, &M) ;
// Set view matrix
D3DXMATRIX view = *g_Camera.GetViewMatrix() ;
pd3dDevice->SetTransform(D3DTS_VIEW, &view) ;
// Set projection matrix
D3DXMATRIX proj = *g_Camera.GetProjMatrix() ;
pd3dDevice->SetTransform(D3DTS_PROJECTION, &proj) ;
pd3dDevice->SetStreamSource(0, g_pVB, 0, sizeof(MyVertexFormat));
pd3dDevice->SetIndices(g_pIB);//sets the current index buffer.
pd3dDevice->SetFVF(FVF_VERTEX);//Sets the current vertex stream declaration.
pd3dDevice->SetTexture(0, g_pCubeTex);
pd3dDevice->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, 0, 0, 24, 0, 12);
#endif
#if phase6
g_pEffect->SetTechnique(g_hFlatTech);
UINT iPass, cPasses;
D3DXMATRIXA16 mWorldViewProjection;
mWorldViewProjection = *g_Camera.GetViewMatrix() * *g_Camera.GetProjMatrix();
V( g_pEffect->SetMatrix( g_hWorldViewProj, &mWorldViewProjection) );
V(g_pEffect->SetValue(g_hDisplacementOffset1, &g_displacementMapOffset1, sizeof(D3DXVECTOR2)));
V(g_pEffect->SetValue(g_hDisplacementOffset2, &g_displacementMapOffset2, sizeof(D3DXVECTOR2)));
V( g_pEffect->Begin( &cPasses, 0 ) );
for( iPass = 0; iPass < cPasses ; iPass++ )
{
V( g_pEffect->BeginPass( iPass ) );
g_pMesh->DrawSubset(0);
V( g_pEffect->EndPass() );
}
V( g_pEffect->End() );
#endif
#if phase4
V(g_pEffect->SetTechnique(g_hTech));
//set WorldViewProject matrix
mWorldViewProjection = *g_Camera.GetViewMatrix() * *g_Camera.GetProjMatrix();
V( g_pEffect->SetMatrix( g_hWorldViewProj, &mWorldViewProjection) );
V( g_pEffect->SetFloatArray( g_hEyePositionInWorld, (const float*)(g_Camera.GetEyePt()), 3) );
V(g_pEffect->SetValue(g_hNormalOffset1, &g_normalMapOffset1, sizeof(D3DXVECTOR2)));
V(g_pEffect->SetValue(g_hNormalOffset2, &g_normalMapOffset2, sizeof(D3DXVECTOR2)));
V(g_pEffect->SetValue(g_hDisplacementOffset1, &g_displacementMapOffset1, sizeof(D3DXVECTOR2)));
V(g_pEffect->SetValue(g_hDisplacementOffset2, &g_displacementMapOffset2, sizeof(D3DXVECTOR2)));
//UINT iPass, cPasses;
V( g_pEffect->Begin( &cPasses, 0 ) );
for( iPass = 0; iPass < cPasses ; iPass++ )
{
V( g_pEffect->BeginPass( iPass ) );
g_pMesh->DrawSubset(0);
V( g_pEffect->EndPass() );
}
V( g_pEffect->End() );
#endif
V( pd3dDevice->EndScene() );
}
}
//--------------------------------------------------------------------------------------
// Handle messages to the application
//--------------------------------------------------------------------------------------
LRESULT CALLBACK MsgProc( HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam,
bool* pbNoFurtherProcessing, void* pUserContext )
{
#if phase1
g_Camera.HandleMessages( hWnd, uMsg, wParam, lParam );
#endif
return 0;
}
//--------------------------------------------------------------------------------------
// Release D3D9 resources created in the OnD3D9ResetDevice callback
//--------------------------------------------------------------------------------------
void CALLBACK OnD3D9LostDevice( void* pUserContext )
{
#if phase2
SAFE_RELEASE(g_pVB);
SAFE_RELEASE(g_pIB);
#endif
#if phase3
SAFE_RELEASE(g_pVertexDecl);
#endif
#if phase4
if( g_pEffect )
g_pEffect->OnLostDevice();
#endif
}
//--------------------------------------------------------------------------------------
// Release D3D9 resources created in the OnD3D9CreateDevice callback
//--------------------------------------------------------------------------------------
void CALLBACK OnD3D9DestroyDevice( void* pUserContext )
{
#if phase2
SAFE_RELEASE(g_pCubeTex);
#endif
#if phase3
SAFE_RELEASE(g_pMesh);
SAFE_RELEASE(g_pNormalTex1);
SAFE_RELEASE(g_pNormalTex2);
SAFE_RELEASE(g_pDisplacementTex1);
SAFE_RELEASE(g_pDisplacementTex2);
#endif
#if phase4
SAFE_RELEASE(g_pEffect);
#endif
}
//--------------------------------------------------------------------------------------
// Initialize everything and go into a render loop
//--------------------------------------------------------------------------------------
INT WINAPI wWinMain( HINSTANCE, HINSTANCE, LPWSTR, int )
{
// Enable run-time memory check for debug builds.
#if defined(DEBUG) | defined(_DEBUG)
_CrtSetDbgFlag( _CRTDBG_ALLOC_MEM_DF | _CRTDBG_LEAK_CHECK_DF );
#endif
// Set the callback functions
DXUTSetCallbackD3D9DeviceAcceptable( IsD3D9DeviceAcceptable );
DXUTSetCallbackD3D9DeviceCreated( OnD3D9CreateDevice );
DXUTSetCallbackD3D9DeviceReset( OnD3D9ResetDevice );
DXUTSetCallbackD3D9FrameRender( OnD3D9FrameRender );
DXUTSetCallbackD3D9DeviceLost( OnD3D9LostDevice );
DXUTSetCallbackD3D9DeviceDestroyed( OnD3D9DestroyDevice );
DXUTSetCallbackDeviceChanging( ModifyDeviceSettings );
DXUTSetCallbackMsgProc( MsgProc );
DXUTSetCallbackFrameMove( OnFrameMove );
// TODO: Perform any application-level initialization here
// Initialize DXUT and create the desired Win32 window and Direct3D device for the application
DXUTInit( true, true ); // Parse the command line and show msgboxes
DXUTSetHotkeyHandling( true, true, true ); // handle the default hotkeys
DXUTSetCursorSettings( true, true ); // Show the cursor and clip it when in full screen
DXUTCreateWindow( L"3D_Math_2DPerlinNoise_ocean" );
DXUTCreateDevice( true, 1024, 768 );
// Start the render loop
DXUTMainLoop();
// TODO: Perform any application-level cleanup here
return DXUTGetExitCode();
}
/*------------------------------------------------------------
PerlinNoise.fx -- achieve Perlin noise
(c) Seamanj.2013/9/4
------------------------------------------------------------*/
struct Material
{
float4 ambient;
float4 diffuse;
float4 specular;
float specularPower;
};
struct DirectionalLight
{
float4 ambient;
float4 diffuse;
float4 specular;
float3 directionInWorld;
};
uniform extern float4x4 g_mWorld;
uniform extern float4x4 g_mWorldInv;
uniform extern float4x4 g_mWorldViewProj;
uniform extern float3 g_eyePositionInWorld;
uniform extern DirectionalLight g_structDirectionalLight;
uniform extern Material g_structMaterial;
// Two normal maps and displacement maps.
uniform extern texture g_texNormalMap1;
uniform extern texture g_texNormalMap2;
uniform extern texture g_texDisplacementMap1;
uniform extern texture g_texDisplacementMap2;
// Texture coordinate offset vectors for scrolling
// normal maps and displacement maps.
uniform extern float2 g_normalOffset1;
uniform extern float2 g_normalOffset2;
uniform extern float2 g_DisplacementOffset1;
uniform extern float2 g_DisplacementOffset2;
// User-defined scaling factors to scale the heights
// sampled from the displacement map into a more convenient
// range.
uniform extern float2 g_scaleHeights;
// Space between grids in x,z directions in local space
// used for finite differencing.
uniform extern float2 g_delta;
// Shouldn't be hardcoded, but ok for demo.
static const float DISPLACEMENTMAP_SIZE = 129.0f;
static const float DISPLACEMENTMAP_DELTA = 1.0f / DISPLACEMENTMAP_SIZE;
sampler g_samNormalMap1 = sampler_state
{
Texture = <g_texNormalMap1>;
MinFilter = ANISOTROPIC;
MaxAnisotropy = 12;
MagFilter = LINEAR;
MipFilter = LINEAR;
AddressU = WRAP;
AddressV = WRAP;
};
sampler g_samNormalMap2 = sampler_state
{
Texture = <g_texNormalMap2>;
MinFilter = ANISOTROPIC;
MaxAnisotropy = 12;
MagFilter = LINEAR;
MipFilter = LINEAR;
AddressU = WRAP;
AddressV = WRAP;
};
sampler g_samDisplacementMap1 = sampler_state
{
Texture = <g_texDisplacementMap1>;
MinFilter = POINT;
MagFilter = POINT;
MipFilter = POINT;
AddressU = MIRROR;
AddressV = MIRROR;
};
sampler g_samDisplacementMap2 = sampler_state
{
Texture = <g_texDisplacementMap2>;
MinFilter = POINT;
MagFilter = POINT;
MipFilter = POINT;
AddressU = MIRROR;
AddressV = MIRROR;
};
struct OutputVS
{
float4 posInHomogeneous : POSITION0;
float3 toEyeInTangent : TEXCOORD0;
float3 lightDirectionInTangent : TEXCOORD1;
float2 texcoord1 : TEXCOORD2;
float2 texcoord2 : TEXCOORD3;
};
float DoDisplacementMapping(float2 texCoord1, float2 texCoord2)
{
// Transform to texel space
float2 texelPos = DISPLACEMENTMAP_SIZE * texCoord1;
// Determine the lerp amounts.
float2 lerps = frac(texelPos);
float height1[4];
//由于移位纹理显示青色(即B,G通道都为1,所以应该是R通道存储的是高度
height1[0] = tex2Dlod(g_samDisplacementMap1, float4(texCoord1, 0.0f, 0.0f)).r;
height1[1] = tex2Dlod(g_samDisplacementMap1, float4(texCoord1, 0.0f, 0.0f)+float4(DISPLACEMENTMAP_DELTA, 0.0f, 0.0f, 0.0f)).r;
height1[2] = tex2Dlod(g_samDisplacementMap1, float4(texCoord1, 0.0f, 0.0f)+float4(0.0f, DISPLACEMENTMAP_DELTA, 0.0f, 0.0f)).r;
height1[3] = tex2Dlod(g_samDisplacementMap1, float4(texCoord1, 0.0f, 0.0f)+float4(DISPLACEMENTMAP_DELTA, DISPLACEMENTMAP_DELTA, 0.0f, 0.0f)).r;
//这里取出来的值范围在[0,1]之内
// Filter displacement map:
float h1 = lerp( lerp( height1[0], height1[1], lerps.x ),
lerp( height1[2], height1[3], lerps.x ),
lerps.y );
texelPos = DISPLACEMENTMAP_SIZE * texCoord2;
lerps = frac(texelPos);
float height2[4];
height2[0] = tex2Dlod(g_samDisplacementMap2, float4(texCoord2, 0.0f, 0.0f)).r;
height2[1] = tex2Dlod(g_samDisplacementMap2, float4(texCoord2, 0.0f, 0.0f)+float4(DISPLACEMENTMAP_DELTA, 0.0f, 0.0f, 0.0f)).r;
height2[2] = tex2Dlod(g_samDisplacementMap2, float4(texCoord2, 0.0f, 0.0f)+float4(0.0f, DISPLACEMENTMAP_DELTA, 0.0f, 0.0f)).r;
height2[3] = tex2Dlod(g_samDisplacementMap2, float4(texCoord2, 0.0f, 0.0f)+float4(DISPLACEMENTMAP_DELTA, DISPLACEMENTMAP_DELTA, 0.0f, 0.0f)).r;
// Filter displacement map:
float h2 = lerp( lerp( height2[0], height2[1], lerps.x ),
lerp( height2[2], height2[3], lerps.x ),
lerps.y );
// Sum and scale the sampled heights.
return g_scaleHeights.x * h1 + g_scaleHeights.y * h2;
}
OutputVS myVertexEntry(float3 positionInLocal : POSITION0,
float2 scaledTexCoord : TEXCOORD0,//供法线纹理使用
float2 normalizedTexCoord : TEXCOORD1)//供移位纹理使用
{
// Zero out our output.
OutputVS outVS = (OutputVS)0;
// Scroll vertex texture coordinates to animate waves.
float2 DisplacementTexCoord1 = normalizedTexCoord + g_DisplacementOffset1;
float2 DisplacementTexCoord2 = normalizedTexCoord + g_DisplacementOffset2;
// float2 DisplacementTexCoord1 = normalizedTexCoord ;
// float2 DisplacementTexCoord2 = normalizedTexCoord ;
// Set y-coordinate of water grid vertices based on displacement mapping.
positionInLocal.y = DoDisplacementMapping(DisplacementTexCoord1, DisplacementTexCoord2) / 480 * 5 ;
// Estimate TBN-basis using finite differencing in local space.
float left = DoDisplacementMapping(DisplacementTexCoord1 + float2(DISPLACEMENTMAP_DELTA, 0.0f),
DisplacementTexCoord2 + float2(DISPLACEMENTMAP_DELTA, 0.0f)) / 480 * 5;
float front = DoDisplacementMapping(DisplacementTexCoord1 + float2(0.0f, DISPLACEMENTMAP_DELTA),
DisplacementTexCoord2 + float2(0.0f, DISPLACEMENTMAP_DELTA))/ 480 * 5;
float3x3 TBN;
TBN[0] = normalize(float3(1.0f, (left - positionInLocal.y)/g_delta.x , 0.0f)); //Tangent
TBN[1] = normalize(float3(0.0f, (front - positionInLocal.y)/g_delta.y , -1.0f));//Binormal
TBN[2] = normalize(cross(TBN[0], TBN[1]));//Normal
// Matrix transforms from object space to tangent space.
float3x3 toTangentSpace = transpose(TBN);
// Transform eye position to local space.
float3 eyePositionInLocal = mul(float4(g_eyePositionInWorld, 1.0f), g_mWorldInv).xyz;
// Transform to-eye vector to tangent space.
float3 toEyeInLocal = eyePositionInLocal - positionInLocal;
outVS.toEyeInTangent = mul(toEyeInLocal, toTangentSpace);
// Transform light direction to tangent space.
float3 lightDirectionInLocal = mul(float4(g_structDirectionalLight.directionInWorld, 0.0f), g_mWorldInv).xyz;
outVS.lightDirectionInTangent = mul(lightDirectionInLocal, toTangentSpace);
// Transform to homogeneous clip space.
outVS.posInHomogeneous = mul(float4(positionInLocal, 1.0f), g_mWorldViewProj);
// Scroll texture coordinates.
outVS.texcoord1 = scaledTexCoord + g_normalOffset1;
outVS.texcoord2 = scaledTexCoord + g_normalOffset2;
// Done--return the output.
return outVS;
}
float4 myPixelEntry(float3 toEyeInTangent : TEXCOORD0,
float3 lightDirectionInTangent : TEXCOORD1,
float2 texcoord1 : TEXCOORD2,
float2 texcoord2 : TEXCOORD3) : COLOR
{
// Interpolated normals can become unnormal--so normalize.
// Note that toEyeW and normalW do not need to be normalized
// because they are just used for a reflection and environment
// map look-up and only direction matters.
toEyeInTangent = normalize(toEyeInTangent);
lightDirectionInTangent = normalize(lightDirectionInTangent);
// Light vector is opposite the direction of the light.
float3 toLightInTangent = -lightDirectionInTangent;
// Sample normal map.
float3 normalInTangent1 = tex2D(g_samNormalMap1, texcoord1);
float3 normalInTangent2 = tex2D(g_samNormalMap2, texcoord2);
// Expand from [0, 1] compressed interval to true [-1, 1] interval.
normalInTangent1 = 2.0f * normalInTangent1 - 1.0f;
normalInTangent2 = 2.0f * normalInTangent2 - 1.0f;
// Average the two vectors.
float3 normalInTangent = normalize( 0.5f * ( normalInTangent1 + normalInTangent2));
//normalInTangent = float3(0,0,1);
// Compute the reflection vector.
float3 r = reflect(lightDirectionInTangent, normalInTangent);
// Determine how much (if any) specular light makes it into the eye.
float s = pow(max(dot(r, toEyeInTangent), 0.0f), g_structMaterial.specularPower);
// Determine the diffuse light intensity that strikes the vertex.
float d = max(dot(toLightInTangent, normalInTangent), 0.0f);
// If the diffuse light intensity is low, kill the specular lighting term.
// It doesn't look right to add specular light when the surface receives
// little diffuse light.
if(d <= 0.0f)
s = 0.0f;
// Compute the ambient, diffuse and specular terms separatly.
float3 spec = s * ( g_structMaterial.specular * g_structDirectionalLight.specular).rgb;
float3 diffuse = d * (g_structMaterial.diffuse*g_structDirectionalLight.diffuse.rgb);
float3 ambient = g_structMaterial.ambient * g_structDirectionalLight.ambient;
float3 final = ambient + diffuse + spec;
// Output the color and the alpha.
return float4(final, g_structMaterial.diffuse.a);
}
technique myTech
{
pass P0
{
// Specify the vertex and pixel shader associated with this pass.
vertexShader = compile vs_3_0 myVertexEntry();
pixelShader = compile ps_3_0 myPixelEntry();
}
}
struct FlatOutputVS
{
float4 posInHomogeneous : POSITION0;
float2 texcoord1 : TEXCOORD0;
float2 texcoord2 : TEXCOORD1;
};
FlatOutputVS flatVertexEntry(float3 positionInLocal : POSITION0,
float2 scaledTexCoord : TEXCOORD0,//供法线纹理使用
float2 normalizedTexCoord : TEXCOORD1)//供移位纹理使用
{
// Zero out our output.
FlatOutputVS outVS = (FlatOutputVS)0;
// Scroll vertex texture coordinates to animate waves.
outVS.texcoord1 = normalizedTexCoord + g_DisplacementOffset1;
outVS.texcoord2 = normalizedTexCoord + g_DisplacementOffset2;
// outVS.texcoord1 = normalizedTexCoord ;
// outVS.texcoord2 = normalizedTexCoord ;
outVS.posInHomogeneous = mul(float4(positionInLocal, 1.0f), g_mWorldViewProj);
// Done--return the output.
return outVS;
}
float4 flatPixelEntry(float2 texCoord1 : TEXCOORD0,
float2 texCoord2 : TEXCOORD1) : COLOR
{
// Transform to texel space
float2 texelPos = DISPLACEMENTMAP_SIZE * texCoord1;
// Determine the lerp amounts.
float2 lerps = frac(texelPos);
float height1[4];
//由于移位纹理显示青色(即B,G通道都为1,所以应该是R通道存储的是高度
height1[0] = tex2D(g_samDisplacementMap1, float4(texCoord1, 0.0f, 0.0f)).r;
height1[1] = tex2D(g_samDisplacementMap1, float4(texCoord1, 0.0f, 0.0f)+float4(DISPLACEMENTMAP_DELTA, 0.0f, 0.0f, 0.0f)).r;
height1[2] = tex2D(g_samDisplacementMap1, float4(texCoord1, 0.0f, 0.0f)+float4(0.0f, DISPLACEMENTMAP_DELTA, 0.0f, 0.0f)).r;
height1[3] = tex2D(g_samDisplacementMap1, float4(texCoord1, 0.0f, 0.0f)+float4(DISPLACEMENTMAP_DELTA, DISPLACEMENTMAP_DELTA, 0.0f, 0.0f)).r;
//这里取出来的值范围在[0,1]之内
// Filter displacement map:
float h1 = lerp( lerp( height1[0], height1[1], lerps.x ),
lerp( height1[2], height1[3], lerps.x ),
lerps.y );
texelPos = DISPLACEMENTMAP_SIZE * texCoord2;
lerps = frac(texelPos);
float height2[4];
height2[0] = tex2D(g_samDisplacementMap2, float4(texCoord2, 0.0f, 0.0f)).r;
height2[1] = tex2D(g_samDisplacementMap2, float4(texCoord2, 0.0f, 0.0f)+float4(DISPLACEMENTMAP_DELTA, 0.0f, 0.0f, 0.0f)).r;
height2[2] = tex2D(g_samDisplacementMap2, float4(texCoord2, 0.0f, 0.0f)+float4(0.0f, DISPLACEMENTMAP_DELTA, 0.0f, 0.0f)).r;
height2[3] = tex2D(g_samDisplacementMap2, float4(texCoord2, 0.0f, 0.0f)+float4(DISPLACEMENTMAP_DELTA, DISPLACEMENTMAP_DELTA, 0.0f, 0.0f)).r;
// Filter displacement map:
float h2 = lerp( lerp( height2[0], height2[1], lerps.x ),
lerp( height2[2], height2[3], lerps.x ),
lerps.y );
// Sum and scale the sampled heights.
float result = (g_scaleHeights.x * h1 + g_scaleHeights.y * h2) / 480;
return float4(result, result,result, 1);
}
technique flatTech
{
pass P0
{
// Specify the vertex and pixel shader associated with this pass.
vertexShader = compile vs_3_0 flatVertexEntry();
pixelShader = compile ps_3_0 flatPixelEntry();
}
}
/*------------------------------------------------------------
Perlin2D.h -- achieve perlin 2d noise
(c) Seamanj.2013/9/4
------------------------------------------------------------*/
#pragma once
#include <vector>
#include <windows.h>
class Perlin2D
{
public:
Perlin2D( int octaves,//需要融合多少倍频
int maxWaveLength,//最高频谐波波长
float maxAmplitude, //最高频谐波幅度
float falloff)//频率每增加一倍，幅度减少的倍数
: m_iOctaves(octaves), m_iMaxWaveLenght(maxWaveLength),
m_fMaxAmplitude(maxAmplitude), m_fFallOff(falloff)
{}
~Perlin2D()
{}
void GenPerlin2D(int width, int height);
void CopyPerlin2DToBuffer(int width, int height, float* pBuffer)
{
GenPerlin2D(width, height);
std::copy(m_vecData.begin(), m_vecData.end(),pBuffer);
}
private:
float _getRandomFloat(float lowBound, float highBound)
{
if( lowBound >= highBound ) // bad input
return lowBound;
// get random float in [0, 1] interval
float f = (rand() % 10000) * 0.0001f;
// return float in [lowBound, highBound] interval.
return (f * (highBound - lowBound)) + lowBound;
}
// cosin插值
// 插值点离a越近，x越小 x = [0,1]
float _interpolation(float a, float b, float x)
{
float ft = x * 3.1415927f;
float f = (1 - cos(ft)) * 0.5f;
return a*(1-f) + b*f;
}
std::vector<float> m_vecData;
int m_iOctaves;
int m_iMaxWaveLenght;
float m_fMaxAmplitude;
float m_fFallOff;
};
/*------------------------------------------------------------
Perlin2D.cpp -- achieve perlin 2d noise
(c) Seamanj.2013/9/4
------------------------------------------------------------*/
#include "DXUT.h"
#include "Perlin2D.h"
//Perlin2D myPerlinNoise(4, 32, 256, 0.5);
void Perlin2D::GenPerlin2D(int width, int height)
{
std::vector<float> vecData(width * height, 0);
m_vecData.clear();
m_vecData.resize(width * height, 0);
srand(GetTickCount());
int waveLength = m_iMaxWaveLenght;
float amplitude = m_fMaxAmplitude;
// k从小变大，倍频逐渐增高
//256+128+64+32 = 480
//产生0 ~ 480的随机数
for(int k = 0; k < m_iOctaves; k++)
{
// 得到一组二维的离散的噪声图，离散步长为waveLength
for(int i = 0; i < height; i += waveLength )
{
// 噪声数组置0
for(int j=0; j < width; j += waveLength)
vecData[i * height + j] = _getRandomFloat(0, amplitude);
}
// 噪声滤波
//32 64 96 < 129-32 = 97
for(int i = waveLength; i < height - waveLength;i += waveLength)
{
for(int j = waveLength;j < width - waveLength; j += waveLength)
{int iLeftUp = ( i - waveLength ) * width + ( j - waveLength );
int iLeftLow = ( i + waveLength ) * width + ( j - waveLength );
int iRightUp = ( i - waveLength ) * width + ( j + waveLength );
int iRightLow = ( i + waveLength ) * width + ( j + waveLength );float corners = ( vecData[iLeftUp] + vecData[iLeftLow] +
vecData[iRightUp] + vecData[iRightLow]) / 24;int iLeft = i * width + (j - waveLength);
int iLower = (i + waveLength) * width + j;
int iRight = i * width + (j + waveLength);
int iUp = (i - waveLength) * width + j;
float sides = ( vecData[iLeft] + vecData[iLower] +
vecData[iRight] + vecData[iUp])/12;
float center = vecData[i * width + j] / 2;
vecData[i * width + j] = corners + sides + center;
}
}
// 插值得到一组二维的连续的噪声图（步长为1）
for(int i = 0;i < height; i++)
{
for(int j = 0; j < width; j++)
{
// 如果i和j都能被waveLength整除，说明该点为已知点
int iModeLength = i % waveLength;
int jModeLength = j % waveLength;
// i和j都不能被waveLength整除
if( iModeLength && jModeLength)
{
float fLeftUp,fLeftLow,fRightUp,fRightLow;
fLeftUp = vecData[ (i - iModeLength) * width + (j - jModeLength) ];
fRightUp = vecData[ (i - iModeLength) * width + (j - jModeLength + waveLength) ];
fLeftLow = vecData[ (i - iModeLength + waveLength) * width +(j - jModeLength)];
fRightLow = vecData[ (i - iModeLength + waveLength) * width + (j - jModeLength + waveLength) ];
float x = (float)iModeLength /(float)waveLength;
float y = (float)jModeLength /(float)waveLength;
float y1 = _interpolation(fLeftUp, fLeftLow, x);
float y2 = _interpolation(fRightUp, fRightLow, x);
vecData[i * width + j] = _interpolation(y1, y2, y);
}
// 只有i不能被整除
else if(iModeLength)
{
float x = (float)iModeLength /(float)waveLength;
vecData[i * width + j] = _interpolation( vecData[(i - iModeLength) * width + j],
vecData[(i - iModeLength + waveLength) * width + j], x );
}
else if(jModeLength)
{
float y = (float)jModeLength /(float)waveLength;
vecData[i * width + j] = _interpolation( vecData[i * width + (j - jModeLength)],
vecData[i * width + (j - jModeLength + waveLength)], y );
}
m_vecData[i * width + j] += vecData[i * width + j];
}
}
// 增大波长和幅度，准备下一次循环
waveLength = waveLength >> 1; // 波长变小一倍
//32 16 8 4分别是步长,中间进行插值,就相当于一个步长是一个周期
//在网上看到的,在一维的情况下，设噪声函数为noise(x)，则通过noise(2x),noise(4x)
//等就可以构造更高频率的噪声。这里把noise考虑成sin函数就行了,一样的道理amplitude *= m_fFallOff