A simple method for rotate images in reportlab

问题

How can we rotate easily an image using reportlab ? I looked for and I do not found an easy method. The only way found comes from http://dods.ipsl.jussieu.fr/orchidee/SANORCHIDEE/TEMP/TEMP_LOCAL/cdat_portable/lib_new_wrong_gcc/python2.4/site-packages/reportlab/test/test_graphics_images.py using for example:

>>> from reportlab.graphics.shapes import Image, Drawing
>>> from reportlab.platypus import SimpleDocTemplate
>>> from reportlab.lib.pagesizes import A4, portrait
>>> from reportlab.lib.units import mm
>>> img = Image(-202/25.4, -125/25.4, 210/25.4, 138/25.4, 'uneBelleImage.png') # (x, y [from lower left corner], width, height, path, **kw)
>>> d = Drawing(0, 0) # (width, height, *nodes, **keywords)
>>> d.add(img)
>>> d.scale(100,100) #(%width, %height)
>>> d.rotate(90)
>>> report=[]
>>> report.append(d)
>>> page = SimpleDocTemplate('toto.pdf', pagesize = portrait(A4), rightMargin=20*mm, leftMargin=20*mm, topMargin=10*mm, bottomMargin = 10*mm)
>>> page.build(report)

This is working, but it is like using a sledgehammer to crack a nut ? Is there a more direct method, using for example the classical reportlab.platypus.Image ? Thanks by advance !

回答1:

to modify an existing flowable, you should create a derived class and override the methods you need to change to get the desired behaviour. So, to create a rotated image you need to override the wrap and draw methods of the existing Image class like this :

from reportlab.platypus.flowables import Image

class RotatedImage(Image):

    def wrap(self,availWidth,availHeight):
        h, w = Image.wrap(self,availHeight,availWidth)
        return w, h
    def draw(self):
        self.canv.rotate(90)
        Image.draw(self)

I = RotatedImage('../images/somelogo.gif')

来源：https://stackoverflow.com/questions/29848988/a-simple-method-for-rotate-images-in-reportlab

标签

python

reportlab