OpenGL Cohen-Sutherland code

Here is an example code for the Cohen-Sutherland line clipping algorithm using OpenGL:

#include <GL/glut.h>

// Define the clipping region constants
const int INSIDE = 0;
const int LEFT = 1;
const int RIGHT = 2;
const int BOTTOM = 4;
const int TOP = 8;

// Define the window coordinates
const int XMIN = 50;
const int XMAX = 250;
const int YMIN = 50;
const int YMAX = 250;

// Define the line coordinates
int x1 = 30;
int y1 = 100;
int x2 = 200;
int y2 = 300;

// Compute the outcode for a point
int computeOutCode(int x, int y) {
    int code = INSIDE;
    if (x < XMIN) {
        code |= LEFT;
    } else if (x > XMAX) {
        code |= RIGHT;
    }
    if (y < YMIN) {
        code |= BOTTOM;
    } else if (y > YMAX) {
        code |= TOP;
    }
    return code;
}

// Clip the line using the Cohen-Sutherland algorithm
void cohenSutherlandLineClip() {
    int outcode1 = computeOutCode(x1, y1);
    int outcode2 = computeOutCode(x2, y2);
    bool accept = false;
    while (true) {
        if (!(outcode1 | outcode2)) {
            accept = true;
            break;
        } else if (outcode1 & outcode2) {
            break;
        } else {
            int x, y;
            int outcodeOut = outcode1 ? outcode1 : outcode2;
            if (outcodeOut & TOP) {
                x = x1 + (x2 - x1) * (YMAX - y1) / (y2 - y1);
                y = YMAX;
            } else if (outcodeOut & BOTTOM) {
                x = x1 + (x2 - x1) * (YMIN - y1) / (y2 - y1);
                y = YMIN;
            } else if (outcodeOut & RIGHT) {
                y = y1 + (y2 - y1) * (XMAX - x1) / (x2 - x1);
                x = XMAX;
            } else {
                y = y1 + (y2 - y1) * (XMIN - x1) / (x2 - x1);
                x = XMIN;
            }
            if (outcodeOut == outcode1) {
                x1 = x;
                y1 = y;
                outcode1 = computeOutCode(x1, y1);
            } else {
                x2 = x;
                y2 = y;
                outcode2 = computeOutCode(x2, y2);
            }
        }
    }
    if (accept) {
        glColor3f(0.0f, 1.0f, 0.0f); // Green color for the clipped line
    } else {
        glColor3f(1.0f, 0.0f, 0.0f); // Red color for the rejected line
    }
    glBegin(GL_LINES);
    glVertex2i(x1, y1);
    glVertex2i(x2, y2);
    glEnd();
}

// Display function
void display() {
    glClear(GL_COLOR_BUFFER_BIT);
    // Draw the window boundaries
    glColor3f(1.0f, 1.0f, 1.0f); // White color for the window
    glBegin(GL_LINE_LOOP);
    glVertex2i(XMIN, YMIN);
    glVertex2i(XMAX, YMIN);
    glVertex2i(XMAX, YMAX);
    glVertex2i(XMIN, YMAX);
    glEnd();
    // Draw the original line
    glColor3f(1.0f, 0.0f, 0.0f); // Red color for the original line
    glBegin(GL_LINES);
    glVertex2i(x1, y1);
    glVertex2i(x2, y2);
    glEnd();
    // Clip the line using the Cohen-Sutherland algorithm
    cohenSutherlandLineClip();
    glFlush();
}

// Main function
int main(int argc, char** argv) {
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
    glutInitWindowSize(300, 300);
    glutInitWindowPosition(100, 100);
    glutCreateWindow("Cohen-Sutherland Line Clipping Algorithm");
    glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
    gluOrtho2D(0, 300, 0, 300);
    glutDisplayFunc(display);
    glutMainLoop();
    return 0;
}