OpenGL绘制圆弧/圆/饼图 2

关注

原创最新推荐文章于 2026-03-02 03:38:37 发布 7.1k 阅读 AI 写同款· GEO 优化 ›

Opengl圆弧绘制算法（Bresenham画圆、角度离散法绘制圆弧、中点画圆） 1.Bresenham画圆 #include<gl/glut.h> #include<math.h> void SetPixel(int x, int y)//画点 { glColor3f(1.0f, 0.0f, 0.0f); glBegin(GL_POINTS); glVertex2i(x, y); glEnd(); } //8路对称 void Cirpot(int x0, int y0, int x, int y) { SetPix 阅读详情

OpenGL绘制圆弧/圆/饼图 2

//rorger,2011 //contact me: jhcyd112@163.com //in this new version, we can both draw a arc/circle/pi with color filled or not. #include "windows.h" #include "glut.h" #include "math.h" #define width 640 #define height 480 void drawArc(double x,double y,double start_angle,double end_angle,double delta_angle,double radius,bool fill) { if (fill) { glBegin(GL_TRIANGLE_FAN); } else { glBegin(GL_LINE_STRIP); } for (double i=start_angle;i<=end_angle;i+=delta_angle) { double vx=x+radius * cos(i); double vy=y+radius*sin(i); glVertex2d(vx,vy); } glEnd(); } void drawCircle(double x, double y, double radius,bool fill) { double pi=acos(-1.0); drawArc(x,y,0,2*pi,pi/180,radius,fill); } void drawPie(double x,double y,double start_angle,double end_angle,double delta_angle,double radius,bool fill) { drawArc(x,y,start_angle,end_angle,delta_angle,radius,fill); if (fill) { glBegin(GL_TRIANGLE_FAN); } else { glBegin(GL_LINES); } glVertex2d(x,y); glVertex2d(x+radius*cos(start_angle),y+radius*sin(start_angle)); if (!fill) { glVertex2d(x,y); } glVertex2d(x+radius*cos(end_angle),y+radius*sin(end_angle)); glEnd(); } void myDisplay(void) // plot the sinc function, using world coordinates { double pi=acos(-1.0); glClear(GL_COLOR_BUFFER_BIT); //画笛卡尔坐标系 glColor3f(1.0,0.0,0.0); glBegin(GL_LINES); glVertex2d(-width/2.0,0); glVertex2d(width/2.0,0); glEnd(); glBegin(GL_LINES); glVertex2d(0,height/2.0); glVertex2d(0,-height/2.0); glEnd(); glColor3f(1.0,1.0,0.0); //draw a circle drawCircle(0,0,100,false); //draw two arcs drawArc(0,0,0,pi/2.0,pi/180,200,false); drawArc(0,0,pi,3*pi/2.0,pi/180,200,true); glEnable(GL_BLEND); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); glColor4f(0.1,1.0f,0.0,0.5); //draw two pies drawPie(0,0,5*pi/4.0,7*pi/4.0,pi/180.0,200,false); drawPie(0,0,pi/4.0,3*pi/4.0,pi/180.0,200,false); glDisable(GL_BLEND); glFlush(); } void myInit(void) { glClearColor(0.0, 0.0, 0.0, 0.0); glColor3f(0.0f, 0.0f, 1.0f); glPointSize(4.0); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluOrtho2D(-width/2.0,width/2.0,-height/2.0,height/2.0); glLineWidth(2.0); } void main(int argc, char** argv) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_SINGLE |GLUT_RGBA); glutInitWindowSize(width,height); glutInitWindowPosition(100,150); glutCreateWindow("LineInterSectoin"); glutDisplayFunc(myDisplay); myInit( ); glutMainLoop( ); }