能不能告诉我怎样画一个五角星?最好把算法讲得明白点,谢谢!!! 最好把算法讲得明白点,谢谢!!! 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 直接调用画多边型的函数.ploygon()好象是这个.参数自己查一下. 是啊,那是五边形啊!!!我想画的是五角星,要是用Polygon()需要10个点的坐标,我就是坐标不会算才问的啊,帮帮忙好么?谢谢了 void CTestView::Drawpentacle(CDC *pDC, CPoint ptCenter,int nRadius){ double pi = 3.1415926535; CPoint point[5]; for(int i=0;i<5;i++) { point[i].x =(long)(ptCenter.x -nRadius*sin((i*72+36)*2*pi/360)); point[i].y =(long)(ptCenter.y +nRadius*cos((i*72+36)*2*pi/360)); } for(i=0;i<5;i++) { pDC->MoveTo(point[i]); pDC->LineTo(point[(i+2)%5]); } } 可以通过opengl来画好处就是可以采用多种方式来显示这个图形这个是我们图形学的大作业具体过程你看看有关opengl的书需要有opengl库的支持// PentagonStar.cpp// OpenGL sdudy// Demonstrates OpenGL GL_TRIANGLES with outline's display// // Program by wangqingsheng. 03/24/6#include <windows.h>#include <gl/gl.h>#include <gl/glu.h>#include "glut.h"// Define a constant for the value of PI#define GL_PI 3.1415f// Rotation amountsstatic GLfloat xRot = 0.0f;static GLfloat yRot = 0.0f;// Flags for effects#define MODE_SOLID 0#define MODE_LINE 1#define MODE_POINT 2int iMode = MODE_SOLID;GLboolean bEdgeFlag = TRUE;///////////////////////////////////////////////////////////////////////////////// Reset flags as appropriate in response to menu selectionsvoid ProcessMenu(int value) { switch(value) { case 1: iMode = MODE_SOLID; break; case 2: iMode = MODE_LINE; break; case 3: iMode = MODE_POINT; break; case 4: bEdgeFlag = TRUE; break; case 5: default: bEdgeFlag = FALSE; break; } glutPostRedisplay(); }// Called to draw scenevoid RenderScene(void) { //另外一组数据/// double radx[5] = {5.8779,-5.8779,-9.5106,-0.0000,9.5106};// double rady[5] = {8.0902,8.0902,-3.0902,-10.0000,-3.0902};// double Radx[5] = {38.0423,0.0000,-38.0423,-23.5114,23.5114};// double Rady[5] = {12.3607,40.0000,12.3607,-32.3607,-32.3607}; //内部五边形的数据 double radx[5] = {7.0534,-7.0534,-11.4127,-0.0000,11.4127}; double rady[5] = {9.7082,9.7082,-3.7082,-12.0000,-3.7082}; //外部五边形的数据 double Radx[5] = {38.0423,0.0000,-38.0423,-23.5114,23.5114}; double Rady[5] = {12.3607,40.0000,12.3607,-32.3607,-32.3607}; // Clear the window glClear(GL_COLOR_BUFFER_BIT); // Draw back side as a polygon only, if flag is set if(iMode == MODE_LINE) glPolygonMode(GL_FRONT_AND_BACK,GL_LINE); if(iMode == MODE_POINT) glPolygonMode(GL_FRONT_AND_BACK,GL_POINT); if(iMode == MODE_SOLID) glPolygonMode(GL_FRONT_AND_BACK,GL_FILL); // Save matrix state and do the rotation glPushMatrix(); glRotatef(xRot, 1.0f, 0.0f, 0.0f); glRotatef(yRot, 0.0f, 1.0f, 0.0f); // Begin the triangles glBegin(GL_TRIANGLES); //按照逆时针的顺序画出直线 glEdgeFlag(bEdgeFlag); glVertex2f(radx[1],rady[1]); glEdgeFlag(TRUE); glVertex2f(radx[0],rady[0]); glVertex2f(Radx[1],Rady[1]); glVertex2f(radx[1],rady[1]); glVertex2f(Radx[2],Rady[2]); glEdgeFlag(bEdgeFlag); glVertex2f(radx[2],rady[2]); glEdgeFlag(TRUE); glVertex2f(radx[2],rady[2]); glVertex2f(Radx[3],Rady[3]); glEdgeFlag(bEdgeFlag); glVertex2f(radx[3],rady[3]); glEdgeFlag(TRUE); glVertex2f(radx[3],rady[3]); glVertex2f(Radx[4],Rady[4]); glEdgeFlag(bEdgeFlag); glVertex2f(radx[4],rady[4]); glEdgeFlag(TRUE); glVertex2f(radx[4],rady[4]); glVertex2f(Radx[0],Rady[0]); glEdgeFlag(bEdgeFlag); glVertex2f(radx[0],rady[0]); glEdgeFlag(TRUE); // Center square as two triangles //画出内部的五边形,都设置为FLASE glEdgeFlag(bEdgeFlag); glVertex2f(radx[0],rady[0]); glVertex2f(radx[1],rady[1]); glVertex2f(radx[2],rady[2]); glVertex2f(radx[3],rady[3]); glVertex2f(radx[4],rady[4]); glVertex2f(radx[0],rady[0]); glVertex2f(radx[3],rady[3]); glEdgeFlag(bEdgeFlag); glVertex2f(radx[0],rady[0]); glVertex2f(radx[2],rady[2]); glEdgeFlag(TRUE); glEnd(); // Restore transformations glPopMatrix(); // Flush drawing commands glutSwapBuffers(); }// This function does any needed initialization on the rendering// context. void SetupRC() { //设置背景色为蓝色 glClearColor(0.1f, 0.5f, 1.0f, 1.0f ); // Set drawing color to green glColor3f(0.0f, 1.0f, 0.0f); }void SpecialKeys(int key, int x, int y) { if(key == GLUT_KEY_UP) xRot-= 5.0f; if(key == GLUT_KEY_DOWN) xRot += 5.0f; if(key == GLUT_KEY_LEFT) yRot -= 5.0f; if(key == GLUT_KEY_RIGHT) yRot += 5.0f; if(key > 356.0f) xRot = 0.0f; if(key < -1.0f) xRot = 355.0f; if(key > 356.0f) yRot = 0.0f; if(key < -1.0f) yRot = 355.0f; // Refresh the Window glutPostRedisplay(); }void ChangeSize(int w, int h) { GLfloat nRange = 100.0f; // Prevent a divide by zero if(h == 0) h = 1; // Set Viewport to window dimensions glViewport(0, 0, w, h); // Reset projection matrix stack glMatrixMode(GL_PROJECTION); glLoadIdentity(); // Establish clipping volume (left, right, bottom, top, near, far) if (w <= h) glOrtho (-nRange, nRange, -nRange*h/w, nRange*h/w, -nRange, nRange); else glOrtho (-nRange*w/h, nRange*w/h, -nRange, nRange, -nRange, nRange); // Reset Model view matrix stack glMatrixMode(GL_MODELVIEW); glLoadIdentity(); }int main(int argc, char* argv[]) { int nModeMenu; int nEdgeMenu; int nMainMenu; glutInit(&argc, argv); //设置窗口显示模式 glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH); //设置窗口大小 glutInitWindowSize(1024,768); //设置窗口显示标题 glutCreateWindow("五角星的显示"); // Create the Menu nModeMenu = glutCreateMenu(ProcessMenu); glutAddMenuEntry("Solid",1); glutAddMenuEntry("Outline",2); glutAddMenuEntry("Points",3); nEdgeMenu = glutCreateMenu(ProcessMenu); glutAddMenuEntry("On",4); glutAddMenuEntry("Off",5); nMainMenu = glutCreateMenu(ProcessMenu); glutAddSubMenu("Mode", nModeMenu); glutAddSubMenu("Edges", nEdgeMenu); glutAttachMenu(GLUT_RIGHT_BUTTON); glutReshapeFunc(ChangeSize); glutSpecialFunc(SpecialKeys); glutDisplayFunc(RenderScene); SetupRC(); glutMainLoop(); return 0; } 循序渐进实现仿QQ界面(六):异型菜单与内建滚动条自绘 屏幕截取编程的问题 【源码】:放源码了,线程类! 网络编程的相关问题 MFC初学者问个小问题。。 如何通过编程改变Edit控件输入字体的大小??? 请教如何获得EDITBOX里的值 如何将xml文件转换成access 数据库中的一个表 谁能帮我看看这个程序:关于复制位图数据到内存 请教一个简单的问题,如何判断用户同时按Shift和Delete键 关于应用程序线程句柄 请问如何用ADO控件直接操作数据库
{
double pi = 3.1415926535;
CPoint point[5];
for(int i=0;i<5;i++)
{
point[i].x =(long)(ptCenter.x -nRadius*sin((i*72+36)*2*pi/360));
point[i].y =(long)(ptCenter.y +nRadius*cos((i*72+36)*2*pi/360));
}
for(i=0;i<5;i++)
{
pDC->MoveTo(point[i]);
pDC->LineTo(point[(i+2)%5]);
}
}
// PentagonStar.cpp
// OpenGL sdudy
// Demonstrates OpenGL GL_TRIANGLES with outline's display
//
// Program by wangqingsheng. 03/24/6
#include <windows.h>
#include <gl/gl.h>
#include <gl/glu.h>
#include "glut.h"
// Define a constant for the value of PI
#define GL_PI 3.1415f// Rotation amounts
static GLfloat xRot = 0.0f;
static GLfloat yRot = 0.0f;// Flags for effects
#define MODE_SOLID 0
#define MODE_LINE 1
#define MODE_POINT 2int iMode = MODE_SOLID;
GLboolean bEdgeFlag = TRUE;///////////////////////////////////////////////////////////////////////////////
// Reset flags as appropriate in response to menu selections
void ProcessMenu(int value)
{
switch(value)
{
case 1:
iMode = MODE_SOLID;
break; case 2:
iMode = MODE_LINE;
break; case 3:
iMode = MODE_POINT;
break; case 4:
bEdgeFlag = TRUE;
break; case 5:
default:
bEdgeFlag = FALSE;
break;
} glutPostRedisplay();
}
// Called to draw scene
void RenderScene(void)
{
//另外一组数据
/// double radx[5] = {5.8779,-5.8779,-9.5106,-0.0000,9.5106};
// double rady[5] = {8.0902,8.0902,-3.0902,-10.0000,-3.0902};
// double Radx[5] = {38.0423,0.0000,-38.0423,-23.5114,23.5114};
// double Rady[5] = {12.3607,40.0000,12.3607,-32.3607,-32.3607}; //内部五边形的数据
double radx[5] = {7.0534,-7.0534,-11.4127,-0.0000,11.4127};
double rady[5] = {9.7082,9.7082,-3.7082,-12.0000,-3.7082};
//外部五边形的数据
double Radx[5] = {38.0423,0.0000,-38.0423,-23.5114,23.5114};
double Rady[5] = {12.3607,40.0000,12.3607,-32.3607,-32.3607};
// Clear the window
glClear(GL_COLOR_BUFFER_BIT);
// Draw back side as a polygon only, if flag is set
if(iMode == MODE_LINE)
glPolygonMode(GL_FRONT_AND_BACK,GL_LINE); if(iMode == MODE_POINT)
glPolygonMode(GL_FRONT_AND_BACK,GL_POINT); if(iMode == MODE_SOLID)
glPolygonMode(GL_FRONT_AND_BACK,GL_FILL);
// Save matrix state and do the rotation
glPushMatrix();
glRotatef(xRot, 1.0f, 0.0f, 0.0f);
glRotatef(yRot, 0.0f, 1.0f, 0.0f);
// Begin the triangles
glBegin(GL_TRIANGLES); //按照逆时针的顺序画出直线
glEdgeFlag(bEdgeFlag);
glVertex2f(radx[1],rady[1]);
glEdgeFlag(TRUE);
glVertex2f(radx[0],rady[0]);
glVertex2f(Radx[1],Rady[1]); glVertex2f(radx[1],rady[1]);
glVertex2f(Radx[2],Rady[2]);
glEdgeFlag(bEdgeFlag);
glVertex2f(radx[2],rady[2]); glEdgeFlag(TRUE);
glVertex2f(radx[2],rady[2]);
glVertex2f(Radx[3],Rady[3]);
glEdgeFlag(bEdgeFlag);
glVertex2f(radx[3],rady[3]);
glEdgeFlag(TRUE); glVertex2f(radx[3],rady[3]);
glVertex2f(Radx[4],Rady[4]);
glEdgeFlag(bEdgeFlag);
glVertex2f(radx[4],rady[4]);
glEdgeFlag(TRUE); glVertex2f(radx[4],rady[4]);
glVertex2f(Radx[0],Rady[0]);
glEdgeFlag(bEdgeFlag);
glVertex2f(radx[0],rady[0]);
glEdgeFlag(TRUE); // Center square as two triangles //画出内部的五边形,都设置为FLASE
glEdgeFlag(bEdgeFlag);
glVertex2f(radx[0],rady[0]);
glVertex2f(radx[1],rady[1]);
glVertex2f(radx[2],rady[2]);
glVertex2f(radx[3],rady[3]);
glVertex2f(radx[4],rady[4]);
glVertex2f(radx[0],rady[0]);
glVertex2f(radx[3],rady[3]);
glEdgeFlag(bEdgeFlag);
glVertex2f(radx[0],rady[0]);
glVertex2f(radx[2],rady[2]);
glEdgeFlag(TRUE);
glEnd(); // Restore transformations
glPopMatrix(); // Flush drawing commands
glutSwapBuffers();
}// This function does any needed initialization on the rendering
// context.
void SetupRC()
{
//设置背景色为蓝色
glClearColor(0.1f, 0.5f, 1.0f, 1.0f ); // Set drawing color to green
glColor3f(0.0f, 1.0f, 0.0f);
}void SpecialKeys(int key, int x, int y)
{
if(key == GLUT_KEY_UP)
xRot-= 5.0f; if(key == GLUT_KEY_DOWN)
xRot += 5.0f; if(key == GLUT_KEY_LEFT)
yRot -= 5.0f; if(key == GLUT_KEY_RIGHT)
yRot += 5.0f; if(key > 356.0f)
xRot = 0.0f; if(key < -1.0f)
xRot = 355.0f; if(key > 356.0f)
yRot = 0.0f; if(key < -1.0f)
yRot = 355.0f; // Refresh the Window
glutPostRedisplay();
}
void ChangeSize(int w, int h)
{
GLfloat nRange = 100.0f; // Prevent a divide by zero
if(h == 0)
h = 1; // Set Viewport to window dimensions
glViewport(0, 0, w, h); // Reset projection matrix stack
glMatrixMode(GL_PROJECTION);
glLoadIdentity(); // Establish clipping volume (left, right, bottom, top, near, far)
if (w <= h)
glOrtho (-nRange, nRange, -nRange*h/w, nRange*h/w, -nRange, nRange);
else
glOrtho (-nRange*w/h, nRange*w/h, -nRange, nRange, -nRange, nRange); // Reset Model view matrix stack
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
}int main(int argc, char* argv[])
{
int nModeMenu;
int nEdgeMenu;
int nMainMenu; glutInit(&argc, argv);
//设置窗口显示模式
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
//设置窗口大小
glutInitWindowSize(1024,768);
//设置窗口显示标题
glutCreateWindow("五角星的显示");
// Create the Menu
nModeMenu = glutCreateMenu(ProcessMenu);
glutAddMenuEntry("Solid",1);
glutAddMenuEntry("Outline",2);
glutAddMenuEntry("Points",3); nEdgeMenu = glutCreateMenu(ProcessMenu);
glutAddMenuEntry("On",4);
glutAddMenuEntry("Off",5); nMainMenu = glutCreateMenu(ProcessMenu);
glutAddSubMenu("Mode", nModeMenu);
glutAddSubMenu("Edges", nEdgeMenu);
glutAttachMenu(GLUT_RIGHT_BUTTON);
glutReshapeFunc(ChangeSize);
glutSpecialFunc(SpecialKeys);
glutDisplayFunc(RenderScene);
SetupRC();
glutMainLoop(); return 0;
}