[reportlab-users] Integrate "Flowable" (SVG) with caching

[Yannick Gosteli @ PETZI]

Robin,

Your example does not match with the case of SVG that we need to render 
in reportlab - I mean we have to build the rasterization.
The ways I know to do this rasterization are "renderPDF.draw()" and 
"renderPM.drawToPIL()".


- CASE 1 -

"renderPDF.draw()" method explicitly needs x & y => there is no way to 
move the point where SVG will be printed via the doForm()

Example:
```
canv.beginForm('svg')
renderPDF.draw(drawing, canv, x=0, y=0)
canv.endForm()

canv.translate(100,100) # no effect
canv.doForm('svg')

-------------


- CASE 2 -

"renderPM.drawToPIL()" will render in a PIL image => we can use it in 
canv.drawImage() => no needs of "form" (useless)

------------


Let me know if you see a better solution

Best regards
Yannick


Yannick Gosteli
PETZI - Association suisse des clubs de musiques actuelles
Billetterie/Petzitickets
yannick.gosteli at petzi.ch
www.petzi.ch - www.petzitickets.ch

Le 16. 11. 17 à 14:38, Robin Becker a écrit :
> On 16/11/2017 12:57, Dinu Gherman wrote:
>> Hi Yannick,
>>
>> have you tried using svglib that I originally wrote in the context of 
>> reportlab? Using it you can import an SVG file and render it as a 
>> reportlab flowable. I’m just not sure if it will be cached and reused 
>> the same way as bitmap images over many pages. And I haven’t really 
>> produced reportlab-generated docs in a long time.
>>
>> https://github.com/deeplook/svglib
>>
>> Cheers,
>>
>> Dinu
>>
> The current code draws directly into the canvas, so if a repeated 
> image is required the code for drawing is repeated and document gets 
> larger.
>
> My hack solution would be to draw into a form and then render the form 
> as often as required.
>
> Yannick is correct in saying that the form is created in it's own 
> space, but if that's zero based then when you use the form you can 
> surround the doForm with
>
> saveState
> scale translate etc etc
> doForm
> restoreState
>
> to position the image anywhere on the page see below.
>
> Obviously this is more work than just using a built in method, but it 
> should be easy enough to make an svg cache.
>
> EG
>
> ############################################
> from reportlab.pdfgen.canvas import Canvas
>
> canv= Canvas('tform.pdf')
>
> #define a form
> canv.beginForm('myform')
> canv.setFont('Times-Roman',10)
> canv.setFillColor((1,0,0))
> canv.setStrokeColor((0,1,0))
> canv.setLineWidth(2)
> s='In myform'
> w=canv.stringWidth(s)
> canv.drawString(2,4,s)
> canv.rect(0,0,2+w,14,stroke=1)
> canv.endForm()
>
> canv.drawString(10,10,'Hello World')
>
>
> canv.saveState()
> canv.translate(100,100)
> canv.lines([(0,-5,0,5), (-5,0,5,0)])
> canv.doForm('myform')
> canv.restoreState()
>
> canv.saveState()
> canv.translate(200,200)
> canv.scale(1.5,1.5)
> canv.lines([(0,-5,0,5), (-5,0,5,0)])
> canv.doForm('myform')
> canv.restoreState()
>
> canv.saveState()
> canv.translate(300,300)
> canv.lines([(0,-5,0,5), (-5,0,5,0)])
> canv.doForm('myform')
> canv.restoreState()
>
> canv.showPage()
> canv.save()
> ############################################
>
>
>
>
>>> Am 15.11.2017 um 22:23 schrieb Yannick Gosteli @ PETZI 
>>> <yannick.gosteli at petzi.ch>:
>>>
>>> Dear,
>>>
>>> I generate a document that contains a SVG repeated several times.
>>> I wonder if there is a way to integrate this SVG with "caching" the 
>>> same way it works with Canvas.drawImage*.
>>>
> ............