用opengl C语言写一段代码，要求用bresenham画线法画直线段，鼠标左键取点，鼠标右键画线

好的，我可以为您提供一个Bresenham算法的代码示例，以使用OpenGL的C语言编写直线段。以下是示例代码：

#include <GL/glut.h>
#include <stdio.h>

int winWidth = 640;
int winHeight = 480;
int pointCount = 0;
int points[2][2];

void init(void) {
    glClearColor(0.0, 0.0, 0.0, 0.0);
    glMatrixMode(GL_PROJECTION);
    gluOrtho2D(0.0, winWidth, 0.0, winHeight);
}

void display() {}

void bresenham(int x1, int y1, int x2, int y2) {
    int dx = abs(x2-x1), dy = abs(y2-y1);
    int p = 2*dy-dx;
    int x = x1, y = y1;

    glBegin(GL_POINTS);
    glVertex2i(x, y);
    while (x < x2) {
        if (p >= 0) {
            y++;
            p += 2*dy-2*dx;
        } else {
            p += 2*dy;
        }
        x++;
        glVertex2i(x, y);
    }
    glEnd();
    glFlush();
}

void mouse(int button, int state, int x, int y) {
    if (button == GLUT_LEFT_BUTTON && state == GLUT_DOWN) {
        points[pointCount][0] = x;
        points[pointCount][1] = winHeight - y;
        pointCount++;
    } else if (button == GLUT_RIGHT_BUTTON && state == GLUT_DOWN) {
        bresenham(points[0][0], points[0][1], points[1][0], points[1][1]);
        pointCount = 0;
    }
}

int main(int argc, char** argv) {
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
    glutInitWindowSize(winWidth, winHeight);
    glutInitWindowPosition(100, 100);
    glutCreateWindow("Bresenham Line Drawing");
    glutDisplayFunc(display);
    glutMouseFunc(mouse);
    init();
    glutMainLoop();
    return 0;
}

该代码使用OpenGL库和GLUT库来实现直线段的创建和显示。Bresenham算法是在while循环中执行的，以在屏幕上绘制直线。当用鼠标左键单击时，该代码会记录所选点的坐标，并在用鼠标右键单击时使用这些点的坐标来绘制直线。