计算机图形学实验三:实现四边形的三视图和透视投影图
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// 计算机图形学实验三.cpp : 定义控制台应用程序的入口点。 // #include "stdafx.h" #include"stdio.h" #include"vector" #include"iostream" #include<gl/glut.h> using namespace std; const int maxnum = 200; vector<int>face[10];//最大数,面数vector int winwidth = 1000, winheight = 600;//窗口的宽高 int pointnum = 4, facenum = 4; double matrix[4][4]= { { 1, 0, 0, 0 }, { 0, 1, 0, 0 }, { 0, 0, 1, 0 }, { 500, 300, 300, 1 } };//初始化单位矩阵 double xoz[4][4]= { {1,0,0,0}, {0,0,0,0}, {0,0,1,0}, {0,0,0,1} };//主视图变换矩阵 double xoy[4][4] { {1,0,0,0}, {0,0,-1,0}, {0,0,0,0}, {0,0,-50,1} };//俯视图变换矩阵 double yoz[4][4] { {0,0,0,0}, {-1,0,0,0}, {0,0,1,0}, {-150,0,0,1} };//侧视图变换矩阵 double dd = -400, nn = -200, mm = -360, ll = -500;//dd视点,平移到适当距离nn,mm,ll double yoy[4][4]= { {1,0,0,0}, {0,1,0,0}, {0,0,0,1/dd}, {ll,mm,0,1+nn/dd} };//一点透视矩阵 struct defpoint { double x, y, z, tag; }point[maxnum], tpoint[maxnum], xozpoint[maxnum], xoypoint[maxnum], yozpoint[maxnum], yoypoint[maxnum]; void thpmidinit() { pointnum = 4; point[0].x = 400, point[0].y = 0, point[0].z = 0, point[0].tag = 1; point[1].x = 400, point[1].y = 200, point[1].z = 0, point[1].tag = 1; point[2].x = 0, point[2].y = 200, point[2].z = 0, point[2].tag = 1; point[3].x =200, point[3].y = 200, point[3].z = 200, point[3].tag = 1; facenum = 4; face[0].push_back(0); face[0].push_back(1); face[0].push_back(2); face[1].push_back(0); face[1].push_back(1); face[1].push_back(3); face[2].push_back(0); face[2].push_back(2); face[2].push_back(3); face[3].push_back(1); face[3].push_back(2); face[3].push_back(3); } void transform(defpoint newpoint[], defpoint oldpoint[], double tran[4][4]) { for (int i = 0; i < pointnum; i++) { double tx = oldpoint[i].x, ty = oldpoint[i].y, tz = oldpoint[i].z, ttag = oldpoint[i].tag; newpoint[i].x = tx*tran[0][0] + ty*tran[1][0] + tz*tran[2][0] + ttag*tran[3][0]; newpoint[i].y = tx*tran[0][1] + ty*tran[1][1] + tz*tran[2][1] + ttag*tran[3][1]; newpoint[i].z = tx*tran[0][2] + ty*tran[1][2] + tz*tran[2][2] + ttag*tran[3][2]; newpoint[i].tag = tx*tran[0][3] + ty*tran[1][3] + tz*tran[2][3] + ttag*tran[3][3]; if (newpoint[i].tag != 0 && newpoint[i].tag != 1) { newpoint[i].x /= newpoint[i].tag; newpoint[i].y /= newpoint[i].tag; newpoint[i].z /= newpoint[i].tag; newpoint[i].tag = 1; } } } void reshape(int w, int h) { winwidth = w; winheight = h; glViewport(0, 0, w, h); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluOrtho2D(0.0, winwidth, 0.0, winheight); } void ondraw(defpoint temppoint[]) { glBegin(GL_LINES); for (int i = 0; i < facenum; i++) { int size = face[i].size(); for (int j = 0; j < size; j++) { glVertex2d(temppoint[face[i][j]].x, temppoint[face[i][j]].z); glVertex2d(temppoint[face[i][(j + 1) % size]].x, temppoint[face[i][(j + 1) % size]].z); } } glEnd(); } void ondraw_0(defpoint temppoint[]) { glColor3f(1.0f, 0.0f, 0.0f); glBegin(GL_LINES); glVertex2d(temppoint[0].x, temppoint[0].y); glVertex2d(temppoint[1].x, temppoint[1].y); glVertex2d(temppoint[0].x, temppoint[0].y); glVertex2d(temppoint[2].x, temppoint[2].y); glVertex2d(temppoint[0].x, temppoint[0].y); glVertex2d(temppoint[3].x, temppoint[3].y); glVertex2d(temppoint[1].x, temppoint[1].y); glVertex2d(temppoint[2].x, temppoint[2].y); glVertex2d(temppoint[1].x, temppoint[1].y); glVertex2d(temppoint[3].x, temppoint[3].y); glVertex2d(temppoint[2].x, temppoint[2].y); glVertex2d(temppoint[3].x, temppoint[3].y); glEnd(); glColor3f(0.0f, 1.0f, 0.0f); glBegin(GL_LINES); glVertex2d(temppoint[0].x, temppoint[0].y); glVertex2d(0, 0); glVertex2d(temppoint[1].x, temppoint[1].y); glVertex2d(0, 0); glVertex2d(temppoint[2].x, temppoint[2].y); glVertex2d(0, 0); glVertex2d(temppoint[3].x, temppoint[3].y); glVertex2d(0, 0); glEnd(); } //绘制坐标系 void oncoordinate() { glColor3f(0.0f, 0.0f, 0.0f); glBegin(GL_LINES); glVertex2d(winwidth / 2, 0); glVertex2d(winwidth / 2, winheight); glVertex2d(0, winheight/2); glVertex2d(winwidth, winheight/2); glVertex2d(winwidth/2+5, winheight-15); glVertex2d(winwidth/2+15, winheight-15); glVertex2d(winwidth/2+5, winheight-25); glVertex2d(winwidth/2+15, winheight-15); glVertex2d(winwidth/2+5, winheight-25); glVertex2d(winwidth/2+15, winheight-25); glVertex2d(winwidth/2-5, winheight-5); glVertex2d(winwidth/2,winheight); glVertex2d(winwidth/2+5, winheight-5); glVertex2d(winwidth/2, winheight); glVertex2d(winwidth/2+25,0+15); glVertex2d(winwidth/2+20,0+10); glVertex2d(winwidth/2+15,0+15); glVertex2d(winwidth/2+20,0+10); glVertex2d(winwidth/2+20,0+10); glVertex2d(winwidth/2+20,0+5); glVertex2d(winwidth/2-5,0+5); glVertex2d(winwidth/2,0); glVertex2d(winwidth/2 + 5,0+5); glVertex2d(winwidth/2, 0); glVertex2d(0+25,winheight/2+15); glVertex2d(0+20, winheight/2+10); glVertex2d(0+15, winheight/2+15); glVertex2d(0+20, winheight/2+10); glVertex2d(0+20, winheight/2+10); glVertex2d(0+20, winheight/2+5); glVertex2d(0+5, winheight/2+5); glVertex2d(0, winheight/2); glVertex2d(0+ 5, winheight/2-5); glVertex2d(0, winheight/2 ); glVertex2d(winwidth-25, winheight/2 + 15); glVertex2d(winwidth-15, winheight/2 + 5); glVertex2d(winwidth-25, winheight/2 + 5); glVertex2d(winwidth-15, winheight/2 + 15); glVertex2d(winwidth-5, winheight/2 -5); glVertex2d(winwidth , winheight/2 ); glVertex2d(winwidth - 5, winheight/2 + 5); glVertex2d(winwidth, winheight/2); glEnd(); } void display() { glClear(GL_COLOR_BUFFER_BIT); oncoordinate(); glColor3f(0.0f, 0.0f, 0.0f); glBegin(GL_LINES); glVertex2d(winwidth/2,0); glVertex2d(winwidth/2, winheight); glVertex2d(0, winheight/2); glVertex2d(winwidth, winheight / 2); glEnd(); glColor3f(1.0f, 0.0f, 0.0f); ondraw(xozpoint); glColor3f(0.0f, 1.0f, 0.0f); ondraw(xoypoint); glColor3f(0.0f, 0.0f, 1.0f); ondraw(yozpoint); glColor3f(1.0f, 0.0f, 0.0f); ondraw_0(yoypoint); glutSwapBuffers(); } void getthpmidview() { transform(xozpoint, point, xoz); transform(xoypoint, point, xoy); transform(yozpoint, point, yoz); transform(yoypoint, point, yoy); transform(xozpoint, xozpoint, matrix); transform(xoypoint, xoypoint, matrix); transform(yozpoint, yozpoint, matrix); transform(yoypoint, yoypoint, matrix); } void initial() { for (int i = 0; i < 10; i++) face[i].clear(); glClearColor(1.0f, 1.0f, 1.0f, 1.0f); thpmidinit(); getthpmidview(); } int main(int argc, char *argv[]) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB); glutInitWindowSize(1000, 600); glutInitWindowPosition(150, 100); glutCreateWindow("三维图形 透视投影图&三视图 演示程序"); glutDisplayFunc(display); glutReshapeFunc(reshape); initial(); glutMainLoop(); return 0; }