GASP (Graphics API for Student

如果你读过或者正在读<<HOW TO THINK LIKE A COMPUTER SCIENTIST>>这本书,你一定知道下面的一段话:

GASP ( G raphics A PI for S tudents of P ython) will enable us to write programs involving graphics. Before you can use GASP, it needs to be installed on your machine. If you are running Ubuntu GNU/Linux, see GASP in Appendix A . Current instructions for installing GASP on other platforms can be found at http://dev.laptop.org/pub/gasp/downloads .

To start gasp after it is installed, try the following:

from gasp import*

begin_graphics()

Circle((200,200),60)

Line((100,400),(580,200))

Box((400,350),120,100)

end_graphics()

按照原书的PYTHON的版本我用PYTHON2.5根本无法 from gasp import *,解释器报错:模块不存在,可是我明明看到模块在SITE_PACKAGES.不知道是不是配置问题,到现在还没有弄清楚.

然后我试下PYTHON2.4,可以FROM GASP IMPORT*拉,不过仍然有问题:

Circle (( 200 , 200 ), 60 )
Traceback (most recent call last):
  File "<pyshell#3>", line 1, in -toplevel-  #这句话是什么意思?
    Circle((200,200),60)
  File "D:\python\lib\site-packages\gasp-0.4.0-py2.4.egg\gasp\api.py", line 170, in __repr__
    return "A Circle instance at (%d, %d) with a radius of %d" %(self.x, self.y, self.radius)
AttributeError: Circle instance has no attribute 'x'  #这句话是什么意思?

前几天和 猫猫 讨论下,我去看了源代码:

class Circle(Shape):
    def __init__(self, center, radius, filled=False,
                                       color=(0,0,0),
                                       thickness=1):
        Shape.__init__(self, center, filled, color, thickness)
        self.radius = radius
      
        backend.create_circle(self)

    def __repr__(self):
        return "A Circle instance at (%d, %d) with a radius of %d" %(self.x, self.y, self.radius)

请教各位这代码有问题吗?

需要说明的是 Line (( 100 , 400 ), ( 580 , 200 )) 的时候解释器OK!

LINE的源代码:

class Line:
    def __init__(self, start, end, color=(0,0,0)):
        self.start = Point(start)
        self.end = Point(end)
        self.color = color

        backend.create_line(self)

    def __repr__(self):
        return "A Line instance from (%d,%d) to (%d,%d)" %(self.x, self.y, self.end.x, self.end.y)

请各位给出出主意,多谢拉!急死拉!