实验1：Bresenham算法

eView cpp implementation of the CEView class include stdafx h include e h include eDoc h include eView h ifdef DEBUG define new DEBUG NEW undef THIS FILE static char THIS FILE FILE endif CEView IMPLEMENT DYNCREATE CEView CView BEGIN MESSAGE MAP CEView CView AFX MSG MAP CEView NOTE the ClassWizard will add and remove mapping macros here DO NOT EDIT what you see in these blocks of generated code AFX MSG MAP Standard printing commands ON COMMAND ID FILE PRINT CView OnFilePrint ON COMMAND ID FILE PRINT DIRECT CView OnFilePrint ON COMMAND ID FILE PRINT PREVIEW CView OnFilePrintPreview END MESSAGE MAP CEView construction destruction CEView CEView TODO add construction code here CEView CEView BOOL CEView PreCreateWindow CREATESTRUCT CEView drawing void Bresenhamline int x1 int y1 int x2 int y2 CDC pDC 对于所有直线均按照从左至右的方向绘制 int x y dy dx right rightleft d if x1 x2 int tempx tempy tempx x1 x1 x2 x2 tempx tempy y1 y1 y2 y2 tempy 根据斜率的情况不同而绘制 if y1 y2 斜率为 0 的情况 for x x1 xSetPixel x y1 2 else if x1 x2 直线为垂直的情况 if y1 y2 使直线按从下往上画 int tempy y1 y1 y2 y2 tempy for y y1 ySetPixel x1 y 2 else dy y2 y1 dx x2 x1 if abs dy abs dx 斜率为 1 或 1 时 x x1 y y1 if dy y2 y x pDC SetPixel x y 2 斜率为 1 else 斜率为 1 for ySetPixel x y 2 斜率为 1 else if abs dy 0 rightleft 2 dx 2 dy d dx 2 dy x x1 y y1 while xSetPixel x y 2 x if d 0 y d d rightleft else d d right 斜率为正时 else 斜率为负时 right 2 dy rightleft 2 dy 2 dx d 2 dy dx x x1 y y1 while xSetPixel x y 2 x if d0 rightleft 2 dx 2 dy d 2 dx dy x x1 y y1 while ySetPixel x y 2 y if d 0 x d d rightleft else d d right 斜率为正时 else 斜率为负时 right 2 dx rightleft 2 dx 2 dy d 2 dx dy x x1 y y1 while y y2 pDC SetPixel x y 2 y if dIsK