added bresenham line drawing algorithm

bresenham_line.py

@@ -0,0 +1,71 @@
+from OpenGL.GL import *
+from OpenGL.GLU import *
+from OpenGL.GLUT import *
+import sys
+import math
+print("Packages imported successfully")
+
+
+def clearscreen():  # clears the windows
+    glClearColor(0.0, 0.0, 0.0, 1.0)
+    gluOrtho2D(-20.0, 20.0, -20.0, 20.0)
+
+
+def plot_points(x,y):
+    print("in points")
+    glClear(GL_COLOR_BUFFER_BIT)
+    glColor3f(0.0, 1.0, 0.0)
+    glPointSize(5.0)
+    glBegin(GL_POINTS)
+    glVertex2f(x,y)
+    glEnd()
+    glFlush()
+
+
+def Bresenham_algo(x1, y1, x2, y2):
+    print('in algo')
+    x = x1
+    y = y1
+    dx,dy = abs(x2-x1),abs(y2-y1)
+    plot_points(x, y)
+    p = 2*dy - dx
+    if dx > dy:
+        while x < x2:
+          x = x+1
+          if p < 0:
+              p = p+2*dy
+          else: 
+              y=y+1
+              p = p+2*dy - 2*dx
+        plot_points(x, y)
+
+    else:
+        while y<y2:
+            y=y+1
+            if p<0:
+                p=p+2*dx
+            else:
+                 x=x+1
+                 p=p+2*dx-2*dy
+        plot_points(x, y)
+
+def Display():
+    x1=float(input('Enter Coordinate X1 :'))
+    x2=float(input('Enter Coordinate X2 :'))
+    y1=float(input('Enter Coordinate Y2 :'))
+    y2=float(input('Enter Coordinate Y2 :'))
+    Bresenham_algo(x1,y1,x2,y2)
+    print('ended')
+
+def main():
+    glutInit(sys.argv)
+    glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB)
+    glutCreateWindow("Bresenham Algorithm")
+    glutInitWindowSize(500, 500)
+    glutInitWindowPosition(50, 50)
+    clearscreen()
+    glutDisplayFunc(Display)
+    glutMainLoop()
+
+
+main()