bresenham画直线源代码

#include <cstdlib> #include <cmath> #include <GL/glut.h> void init() { glClearColor(0.0, 0.0, 0.0, 0.0); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluOrtho2D(0.0, 300, 0.0, 300); } void setPixel(int x, int y) { glBegin(GL_POINTS); glVertex2d(x, y); glEnd(); } void lineBres(int x0, int y0, int xEnd, int yEnd) { int dx = fabs((float)(xEnd-x0)), dy = fabs((float)(yEnd - y0)); int p = 2*dy -dx; int twoDy =2*dy, twoDyMinusDx = 2*(dy - dx); int x, y; if (x0 > xEnd) { x = xEnd; y = yEnd; xEnd = x0; yEnd = y0; } else { x = x0; y = y0; } setPixel(x, y); while (x < xEnd) { x++; if (p < 0) { p += twoDy; } else { y++; p += twoDyMinusDx; } setPixel(x, y); } } void display() { glClear(GL_COLOR_BUFFER_BIT); glColor3f(1.0, 0.0, 0.0); lineBres(0, 0, 250, 200); glFlush(); } int main(int argc, char** argv) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutInitWindowPosition(100, 100); glutInitWindowSize(300, 300); glutCreateWindow("DrawBresenhamLine"); init(); glutDisplayFunc(display); glutMainLoop(); return 0; }