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Print Layout : print result issues

Mar 12, 2015 at 5:40 PM
Hi,
we are developing an application using DotSpatial.
We have another problems with the print result of the layout (thanks jany_ for your previous correction in changesets 74959 & 74996)
The following image shows my layout configuration containg 2 shape files, a line and a polygon layer:
Image

The following image shows now the result of the printing (to simulate a print, I have print a pdf file using PDF Creator. I have the same result if I print directly to a printer):
Image

Another zooms
Image

Image

As you can see, the lines and the hatch are not displayed with a good result. It seems that its linked to the number of points in the lines geometry: I have a lot of points in the line geometry definition
You can download the shape files here:
SHP
Someone has already seen these issues? how can we have a print result conform with what we seen in the layout?
Mar 25, 2015 at 10:38 AM
Another link to download the shp files:
https://www.transfernow.net/fr/820hf1i3whe1

Thanks!
Apr 13, 2015 at 1:39 PM
Hi,
any news on this subject?
Has someone the same problem?
Thanks
Best regards
Apr 13, 2015 at 3:47 PM
I had a look at this but thought that borders of the shapes looked bad all the same whether they were shown in DemoMap or on a printed pdf.

I've been working on drawing circles and ellipses. My ellipses look good but the circles don't. That comes from using Point.Buffer() for the circles and calculating the coordinates of the ellipses in steps of Math.PI / 360 myself. Might be the border of your circle looks bad because you're still not using enough points to define it.

The IAP-shapes look as if you used more than 2 points for the straight lines. If so that could explain why those lines don't look as straight as they should.


The problem with the hatches could be caused by the resolution used for printing but I didn't have the time yet to have a look at that.
Apr 13, 2015 at 3:58 PM
Thanks jany for your answer.
All our line are computed geodetic line, so there is always more than 2 points, also because there are a lot of curve lines, and we can not modify this.
But in the GIS viewer and in the Layout view all the shapes lines look fine; the problem appear only when we print on a pdf or on paper.
What happens during the print process? Dotspatial generates a picture?
May 7, 2015 at 4:17 PM
Hi,
any news on this subject?
We are developing a solution based on DotSpatial in order to generates charts using the layout module, but unfortunately we can not for the moment print the charts (or export as pdf using Pdf Creator for example), due to the problems mentioned above.
Best regards
May 22, 2015 at 12:05 PM
I had a look at this again.

The hatches are drawn with a hatch brush. That looks alright when you draw it on screen. But whichever way I tried, I could not get it to look good when printed. This might be because the resolution of the printer (600dpi for my pdf-printer) differs from that of the preview (96dpi).

The only solution I can think of would be to define the hatch patterns in a way that lets us paint them line by line.
That means as long as that is not changed you either have to life with the way your hatches look or don't use them.

The problem with the shapes lines results from the different resolutions (printer/preview), too. Because the printers resolution is higher you print a sharper image which looks more jagged. As I said before that would not happen if the definition of your shapes were different.

I used the simplify lines tool on your IAP shape and thought that the printed version of the resulting shape looked way better than the print of the IAP shape.
The simplify lines tool doesn't seem to be able to work with polygons. But I think it would be easy to change that.
This could be a way for you to get your shapes to look smoother.