www.pudn.com > OpenGL_3d_terrain.rar > MyGrid.cpp

// MyGrid.cpp: implementation of the CMyGrid class. 
// 
////////////////////////////////////////////////////////////////////// 
 
#include "stdafx.h" 
#include "MyTerrain1.h" 
#include "MyGrid.h" 
 
#ifdef _DEBUG 
#undef THIS_FILE 
static char THIS_FILE[]=__FILE__; 
#define new DEBUG_NEW 
#endif 
 
////////////////////////////////////////////////////////////////////// 
// Construction/Destruction 
////////////////////////////////////////////////////////////////////// 
struct cvPoint 
{ 
	float x, y, z; //点的坐标 
}; 
 
//矢量相乘 C = A x B  
void vect_mult(struct cvPoint *A, struct cvPoint *B, struct cvPoint *C) 
{ 
	C->x = A->y*B->z - A->z*B->y; 
	C->y = A->z*B->x - A->x*B->z; 
	C->z = A->x*B->y - A->y*B->x; 
} 
 
// Catmull-Rom Curve calculations 
void cvCatmullRom(struct cvPoint *p, float t, struct cvPoint *outp) 
{ 
	float t2, t3, t1; 
 
	t2 = t*t; 
	t3 = t*t*t; 
	t1 = (1-t)*(1-t); 
 
	outp->x = (-t*t1*p[0].x + (2-5*t2+3*t3)*p[1].x + t*(1+4*t-3*t2)*p[2].x - t2*(1-t)*p[3].x)/2; 
	outp->y = (-t*t1*p[0].y + (2-5*t2+3*t3)*p[1].y + t*(1+4*t-3*t2)*p[2].y - t2*(1-t)*p[3].y)/2; 
	outp->z = (-t*t1*p[0].z + (2-5*t2+3*t3)*p[1].z + t*(1+4*t-3*t2)*p[2].z - t2*(1-t)*p[3].z)/2; 
} 
 
 
 
CMyGrid::CMyGrid() 
{ 
	grid = NULL; 
	m_width = 0; 
	m_height = 0; 
	SetCellLength(1.0); 
	SetHeight(0, 2); 
	SetInterpolationLevel(20); 
	SetDimensions(10, 10); 
 
} 
 
//带参数的构造函数 
CMyGrid::CMyGrid(int width, int height) 
{ 
	grid = NULL; 
	m_width = 0; 
	m_height = 0; 
	SetCellLength(1.0); 
	SetDimensions(width, height); 
	SetHeight(0, 2); 
	SetInterpolationLevel(20); 
} 
 
CMyGrid::~CMyGrid() 
{ 
	if (grid) delete [] grid; 
 
} 
 
// 设置地形的大小 
void CMyGrid::SetDimensions(int width, int height) 
{ 
	if (grid) delete [] grid; 
	grid = new float [height*width]; 
 
	for (int i=0; i<(height*width); i++) grid[i] = 0; 
	m_width = width; 
	m_height = height; 
} 
 
// 网格的边长 
void CMyGrid::SetCellLength(float l) 
{ 
	m_cell = l; 
} 
 
// 设置地形最小和最大高度 
void CMyGrid::SetHeight(float min, float max) 
{ 
	m_min = min; 
	m_max = max; 
} 
 
// 曲线内的插值阶数(曲线内点的个数) 
void CMyGrid::SetInterpolationLevel(int level) 
{ 
	m_interpol_level = level; 
} 
 
// 网格的生成 
void CMyGrid::GenerateNewGrid() 
{ 
	srand((unsigned int)time(NULL)); 
 
	for (int i=0; i 0) 
						{ 
							// 计算矢量A 
							a.x = temp[l].x - outp.x; 
							a.y = temp[l].y - outp.y; 
							a.z = temp[l].z - outp.z; 
 
							// 计算矢量B 
							b.x = temp[l-1].x - outp.x; 
							b.y = temp[l-1].y - outp.y; 
							b.z = temp[l-1].z - outp.z; 
							 
							// 计算矢量C = AxB 
							vect_mult(&a, &b, &c); 
 
							glNormal3f(c.x, c.y, c.z); 
 
							glTexCoord2f(t_int_x, t_int_y); 
							glVertex3f(outp.x, outp.y, outp.z); 
					 
							glTexCoord2f(t_int_x-int_const, t_int_y); 
							glVertex3f(temp[l].x, temp[l].y, temp[l].z); 
							 
							glTexCoord2f(t_int_x-int_const, t_int_y-int_const); 
							glVertex3f(temp[l-1].x, temp[l-1].y, temp[l-1].z); 
						} 
						temp[l] = outp; 
					} 
					t_int_y += int_const; 
				} 
				flag = 1; 
				t_int_x += int_const; 
			} 
			 
		} 
	} 
	glEnd(); 
 
	delete [] temp; 
	glEndList(); 
}