如何在三维坐标中选择点

简介

如何在三维坐标中选择点是一个非常非常有用的操作。

code

void pick_point(int x, int y, double p[3])
{
	GLint viewport[4];
	glGetIntegerv(GL_VIEWPORT, viewport);
	GLdouble winX = double(x);
	GLdouble winY = double(viewport[3] - y);
	GLfloat winZ = 0.0;
	glReadPixels((int)winX, (int)winY, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT, &winZ);
	gluUnProject(winX, winY, (GLdouble)winZ, modelview_matrix_, projection_matrix_, viewport, &p[0], &p[1], &p[2]);
}

参考链接

https://blog.csdn.net/donglei2007/article/details/7868229