OpenGL学习之路-2

glut程序

8.多窗口且子窗口能够跟随reshape的变化而变化

///
#include 
#include 


///
int winWidth, winHeight;                                    //  <<=======NEW!!!
int mainWinID;                                              //  <<=======NEW!!!
int subWinID0(0), subWinID1(0), subWinID2(0), subWinID3(0); //  <<=======NEW!!!


///
void myMainWinDraw(void);
void myMainWinReshape(int _width, int _height);

void mySubWinDrawSphere(void);
void mySubWinDrawTeapot(void);
void mySubWinDrawTorus(void);
void mySubWinDrawIcos(void);


///
int main(int argc,char** argv) {
    glutInit(&argc,argv);
	glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB);
	glutInitWindowSize(400, 400);
	glutInitWindowPosition(0, 0);

	mainWinID = glutCreateWindow("Hello");

	glutDisplayFunc(myMainWinDraw);
	glutReshapeFunc(myMainWinReshape);

	glutMainLoop();
	return 0;
}


///
void myMainWinReshape(int _width, int _height) {
	winWidth  = _width;                  // <<==============NEW!!!
	winHeight = _height;                 // <<==============NEW!!!

	if (subWinID0)                       // <<==============NEW!!!
		glutDestroyWindow(subWinID0);     // <<==============NEW!!!

    subWinID0 = glutCreateSubWindow(mainWinID, 0, 0,   // <<=======NEW!!!
			                          winWidth>>1, winHeight>>1);
    glutDisplayFunc(mySubWinDrawSphere);              // <<=======NEW!!!


	if (subWinID1) {
		glutDestroyWindow(subWinID1);
	}
	subWinID1 = glutCreateSubWindow(mainWinID, winWidth>>1, 0,
		                             winWidth>>1, winHeight>>1);
	glutDisplayFunc(mySubWinDrawTeapot);

	if (subWinID2)
		glutDestroyWindow(subWinID2);
	subWinID2 = glutCreateSubWindow(mainWinID, 0, winHeight>>1,
			                          winWidth>>1, winHeight>>1);
	glutDisplayFunc(mySubWinDrawTorus);

	if (subWinID3)
		glutDestroyWindow(subWinID3);
	subWinID3 = glutCreateSubWindow(mainWinID, winWidth>>1, winHeight>>1,
		                             winWidth>>1, winHeight>>1);

	glutDisplayFunc(mySubWinDrawIcos);
}


///
void myMainWinDraw() {
	glClearColor(0.0, 0.0, 0.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);

	glFlush();
}


///
void mySubWinDrawSphere(void) {
	glClearColor(0.0, 0.0, 1.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);

	glRotatef(30, 1.0f, 1.0f, 1.0f);
	glutWireSphere(0.8f, 20, 20);

	glFlush();
}


///
void mySubWinDrawTeapot(void) {
	glClearColor(1.0, 1.0, 0.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);

	glutWireTeapot(0.5f);

	glFlush();
}


///
void mySubWinDrawTorus(void) {
	glClearColor(0.0, 1.0, 1.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);

	glutWireTorus(0.3f, 0.6f, 20, 30);

	glFlush();
}


///
void mySubWinDrawIcos(void) {
	glClearColor(1.0, 0.0, 1.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);

	glRotatef(30, 1.0f, 1.0f, 1.0f);
   glutWireIcosahedron();

	glFlush();
}


///

新增的知识点：

1.回调函数myMainWinReshape中：改变窗口大小时，先将原来子窗口销毁（如果存在的话），再重新产生新的子窗口。

2.glutDestroyWindow：销毁窗口

道理上是这个样子，但是我在实际运行过程中，拖动鼠标改变窗口大小时，出现了问题。 

差不多是说，没有注册给窗口6的回调函数。可能和我这个freeglut有关系的。暂时没有解决。

9.可控制的子窗口显示

///
#include 
#include 


///
void myMainWinDraw(void);
void myMainWinReshape(int _width, int _height);
void myMainWinKeyboard(unsigned char _key, int _x, int _y);

void mySubWinDrawSphere(void);
void mySubWinDrawTeapot(void);
void mySubWinDrawTorus(void);
void mySubWinDrawIcos(void);


///
int winWidth, winHeight;
int mainWinID;
int subWinID0(0), subWinID1(0), subWinID2(0), subWinID3(0);

// <<================= NEW !!!!!!
bool isShowSubWin0(1), isShowSubWin1(1), isShowSubWin2(1), isShowSubWin3(1);


///
int main(int argc,char** argv) {
    glutInit(&argc,argv);
	glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB);
	glutInitWindowSize(400, 400);
	glutInitWindowPosition(0, 0);

	mainWinID = glutCreateWindow("Hello");

	glutDisplayFunc(myMainWinDraw);
	glutReshapeFunc(myMainWinReshape);
	glutKeyboardFunc(myMainWinKeyboard);

	glutMainLoop();
	return 0;
}


///
void myMainWinReshape(int _width, int _height) {
	winWidth  = _width;
	winHeight = _height;

	if (subWinID0) {
		glutDestroyWindow(subWinID0);
		subWinID0 = 0;
	}
	if (isShowSubWin0) {
      subWinID0 = glutCreateSubWindow(mainWinID, 0, 0,  winWidth>>1, winHeight>>1);
      glutDisplayFunc(mySubWinDrawSphere);
	}

	if (subWinID1) {
		glutDestroyWindow(subWinID1);
		subWinID1 = 0;
	}
	if (isShowSubWin1) {
	   subWinID1 = glutCreateSubWindow(mainWinID, winWidth>>1, 0,
		                                winWidth>>1, winHeight>>1);
	   glutDisplayFunc(mySubWinDrawTeapot);
	}

	if (subWinID2) {
		glutDestroyWindow(subWinID2);
		subWinID2 = 0;
	}
	if (isShowSubWin2) {
	   subWinID2 = glutCreateSubWindow(mainWinID, 0, winHeight>>1,
			                             winWidth>>1, winHeight>>1);
	   glutDisplayFunc(mySubWinDrawTorus);
	}

	if (subWinID3) {
		glutDestroyWindow(subWinID3);
		subWinID3 = 0;
	}
	if (isShowSubWin3) {
	   subWinID3 = glutCreateSubWindow(mainWinID, winWidth>>1, winHeight>>1,
		                                winWidth>>1, winHeight>>1);
	   glutDisplayFunc(mySubWinDrawIcos);
	}
}


///
void myMainWinDraw() {
	glClearColor(0.0, 0.0, 0.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);

	glFlush();
}


//      <<<<<===================== NEW !!!!!
#define RENEW    myMainWinReshape(winWidth, winHeight);\
                 glutPostRedisplay();\
	             //myMainWinDraw();

///
void myMainWinKeyboard(unsigned char _key, int _x, int _y) {
	switch (_key) {
	  case 'a':
		  isShowSubWin0 = !isShowSubWin0;
		  RENEW;
		  break;
	  case 's':
		  isShowSubWin1 = !isShowSubWin1;
		  RENEW;
		  break;
	  case 'z':
		  isShowSubWin2 = !isShowSubWin2;
		  RENEW;
		  break;
	  case 'x':
		  isShowSubWin3 = !isShowSubWin3;
		  RENEW;
		  break;
	  case 'f':
		  // <<================== NEW !!!
		  glutFullScreen();
		  break;
	  case 'v':
		  // <<================== NEW !!!
		  glutSetWindow(mainWinID);
		  glutReshapeWindow(300, 300);
		  break;
	  case 'w':
		  // <<================== NEW !!!
		  glutSetWindow(subWinID0);
		  glutReshapeWindow(100, 100);
	}
}

#undef RENEW    // <<================== NEW !!!

///
void mySubWinDrawSphere(void) {
	glClearColor(0.0, 0.0, 1.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);

	glRotatef(30, 1.0f, 1.0f, 1.0f);
	glutWireSphere(0.8f, 20, 20);

	glFlush();
}


///
void mySubWinDrawTeapot(void) {
	glClearColor(1.0, 1.0, 0.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);

	glutWireTeapot(0.5f);

	glFlush();
}


///
void mySubWinDrawTorus(void) {
	glClearColor(0.0, 1.0, 1.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);

	glutWireTorus(0.3f, 0.6f, 20, 30);

	glFlush();
}


///
void mySubWinDrawIcos(void) {
	glClearColor(1.0, 0.0, 1.0, 0.0);
	glClear(GL_COLOR_BUFFER_BIT);

	glRotatef(30, 1.0f, 1.0f, 1.0f);
   glutWireIcosahedron();

	glFlush();
}


///

引入bool量isShowSubWin0, isShowSubWin1, isShowSubWin2, isShowSubWin3来判断是否应该显示该子窗口。