Bresenham绘制粗线.zip_Bresenham

// Bresenham绘制粗线.cpp : 此文件包含 "main" 函数。程序执行将在此处开始并结束。 // #include <GL/glut.h> #include <cmath> void init(void) { glClearColor(1.0, 1.0, 1.0, 0.0); glMatrixMode(GL_PROJECTION); gluOrtho2D(0.0, 200.0, 0.0, 200.0); } void lineBres(int x0, int y0, int xEnd, int yEnd, int width) { glClear(GL_COLOR_BUFFER_BIT); glColor3f(1.0, 0.5, 0.5); glEnable(GL_POINT_SMOOTH); int dx = fabs(xEnd - x0), dy = fabs(yEnd - y0); int p = 2 * dy - dx; int q = 2 * dx - dy; int twoDy = 2 * dy, twoDyMinusDx = 2 * (dy - dx); int twoDx = 2 * dx, twoDxMinusDy = 2 * (dx - dy); int x=x0, y=y0; glBegin(GL_POINTS); glVertex2i(x, y); glEnd(); int minWidth, maxWidth; width--; if (width % 2 == 0) { minWidth = -width / 2; maxWidth = width / 2; } else { minWidth = -width / 2 - 1; maxWidth = width / 2; } if (fabs(dx) > fabs(dy)) { while(x<xEnd) { x++; if(p<0) p += twoDy; else { y++; p += twoDyMinusDx; } glBegin(GL_POINTS); for (int i = minWidth; i <= maxWidth; i++) glVertex2i(x, y + i); glEnd(); } } else { while (y < yEnd) { y++; if (q < 0) q += twoDx; else { x++; q += twoDxMinusDy; } glBegin(GL_POINTS); for (int i = minWidth; i <= maxWidth; i++) glVertex2i(x + i, y); glEnd(); } } glFlush(); } void pointFun() { int x0 = 0, y0 = 0, xEnd = 100, yEnd = 200, width = 5; lineBres(x0, y0, xEnd, yEnd, width); } int main(int argc, char** argv) { glutInit(&argc, argv); glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutInitWindowPosition(0, 0); glutInitWindowSize(400, 400); glutCreateWindow("An Example OpenGL Program"); init(); glutDisplayFunc(pointFun); glutMainLoop(); return 0; }