2题

//

// 程序名称：消隐图

// 功    能：实现预设三维物体的消隐图。

// 编译环境：VS2019，EasyX_20220116

// 最后修改：2022-4-14

#include <graphics.h>

#include <conio.h>

#include <iostream>

#include <stdio.h>

#include <stdlib.h>

using namespace std;

//顶点表

float point[20][4] = {

{0,0,150,1},//0

{250,0,150,1},//1

{250,0,50,1},//2

{300,0,50,1},//3

{300,0,0,1},//4

{300,200,0,1},//5

{0,200,0,1},//6

{0,200,100,1},//7

{0,150,100,1},//8

{0,150,150,1},//9

{50,150,150,1},//10

{50,50,150,1},//11

{250,50,150,1},//12

{250,50,50,1},//13

{150,50,50,1},//14

{150,200,50,1},//15

{100,200,100,1},//16

{100,150,100,1},//17

{300,200,50,1},//18

{0,0,0,1}//19

};

//环表

int ring[72] = {

//parallel XOY

0,1,12,11,10,9,0,//visible

8,17,16,7,8,//visible

2,3,18,15,14,13,2,//visible

4,19,6,5,4,//invisible

//parallel XOZ

1,2,3,4,19,0,1,//invisible

12,13,14,11,12,//visible

10,17,8,9,10,//visible

5,6,7,16,15,18,5,//visible

//parallel YOZ

1,2,13,12,1,//visible

0,9,8,7,6,19,0,//invisible

3,4,5,18,3,//visible

//slope

11,10,17,16,15,14,11 //visible

};

//面表

int surface[12][2] = {

//parallel XOY

{0,6},{7,11},{12,18},{19,23},

//parallel XOZ

{24,30},{31,35},{36,40},{41,47},

//parallel YOZ

{48,52},{53,59},{60,64},

//slope

{65,71}

};

//矩阵乘法，a*b=c，a[m][n]，b[n][q]，c[m][q]

void MatrixMultiplication(float a[20][4], float b[4][4], float c[20][4]) {

int i = 0, j = 0, k = 0;

for (i = 0; i < 20; i++) {

for (j = 0; j < 4; j++) {

c[i][j] = 0;

for (k = 0; k < 4; k++) {

c[i][j] = c[i][j] + a[i][k] * b[k][j];

}

}

}

}

//主函数

int main() {

//float point[20][4]

//int ring[72]

//int surface[12][2]

int i, j, start, end;

//正等轴测向量

float zdz[4][4] = { {0.707,0,-0.408,0},{-0.707,0,-0.408,0},{0,0,0.8165,0},{0,0,0,1} };

//备份顶点集

float point1[20][4];

double x1, x2, x3, z1, z2, z3;

//E值

double valueE[12];

//矩阵乘法=>正等轴测

MatrixMultiplication(point, zdz, point1);

initgraph(1000, 700);

//移动x坐标和y坐标

for (i = 0; i < 20; i++) {

point1[i][0] = 500 - point1[i][0] * 1.2;//220

point1[i][2] = 350 - point1[i][2] * 1.2;//140

}

//求E的值

for (i = 0; i < 12; i++) {

j = surface[i][0];

x1 = point1[ring[j]][0];

x2 = point1[ring[j + 1]][0];

x3 = point1[ring[j + 2]][0];

z1 = point1[ring[j]][2];

z2 = point1[ring[j + 1]][2];

z3 = point1[ring[j + 2]][2];

valueE[i] = (z2 - z1) * (x3 - x2) - (x2 - x1) * (z3 - z2);

}

for (i = 0; i < 12; i++) {

if (valueE[i] >= 0) {

start = surface[i][0];

end = surface[i][1];

for (j = start; j < end; j++) {

line(point1[ring[j]][0], point1[ring[j]][2], point1[ring[j + 1]][0], point1[ring[j + 1]][2]);

}

}

}

_getch();

closegraph();

return 0;

}

1题

//

// 程序名称：正等轴测投影图

// 功    能：实现预设三维物体的正等轴测投影图。

// 编译环境：VS2019，EasyX_20220116

// 最后修改：2022-4-14

#include <graphics.h>

#include <conio.h>

#include <iostream>

#include <math.h>

using namespace std;

//和分割线之间的距离

const int gap = 50;

//预设三维体的点坐标

int X[33] = { 0,0,0,0,0,0,0,0,100,100,0,100,100,100,100,100,100,100,100,0,0,0,0,100,100,100,100,0,0,0,0,100,100 };

int Y[33] = { 0,0,250,250,200,150,0,0,0,0,0,0,150,200,250,250,0,0,150,150,0,150,200,200,150,200,250,250,200,250,250,250,250 };

int Z[33] = { 100,0,0,50,50,100,100,0,0,100,100,100,100,50,50,0,0,100,100,100,100,100,50,50,100,50,50,50,50,50,0,0,50 };

//顶点总数

const int num = 33;

//正等轴测图绘制

void fun() {

POINT* p = new POINT[num];

for (int i = 0; i < num; i++) {

p[i].x = 0.7071 * X[i] - 0.7071 * Y[i] + 500;

p[i].y = 0.4082 * X[i] + 0.4082 * Y[i] - 0.8165 * Z[i] + 350;

}

for (int i = 0; i < num - 1; i++) {

setcolor(YELLOW);

line(p[i].x, p[i].y, p[i + 1].x, p[i + 1].y);

}

free(p);

}

int main() {

initgraph(1000, 700);

//调用函数

fun();

_getch();

closegraph();

return 0;

}