print composer: exporting to PDF does not resize correctly vectors if symbology is in mm. Works fine if units are map units.

[lutra]

Add a point vector layer and in ita symbology assign to it a pretty large size in millimeters.

Open the print composer and export to PDF: the size of points does not scale as in the composer/canvas.

Same process, but now define the size in map units instead of mm: exporting to PDF produce a correct result.

[mhugent]

Do you mean it does not scale the same relatively to the background map? That's because if you specify the size as e.g. 10 mm, it will be 10mm on screen and 10mm in printout.

[lutra]

I'm using the new symbology. If I set a point as a circle symbol with 15mm of diameter, on screen (in the canvas and in the composer) I can measure 11m, then on paper (printing as PDF) I can measure 14mm.

In general there is a 1mm difference between what was set in the symbology properties and the paper. For my uses it is ok, maybe for others it is not.

On screen the measure doesn't seems to be the same as the one set in the symbology properties (20mm become 14.5mm, 50mm become 37mm, etc.).

[lutra]

see also #3125

[mhugent]

I tested on several machines, and the printer output was usually close to 15 mm. On screen, I had different results, it was correct on some and wrong on others (e.g. 11 mm instead of 15). I think this might be do to the fact that the x-server (and thus Qt) does not always give the correct dpi number.

[lutra]

see also #2635

[zanollim]

I attached two PDF exported with the composer.

They both represent the same area at the same scale (1:5000) on the same page size (A4).

The only difference is the quality (100dpi and 300dpi)

As you can see, they are very different, but they should be identical!

I think that the 300dpi PDF is a bigger image resized to fit the 1:5000 scale. I think that this is wrong!

[zanollim]

Sorry, my attachments are a little box of the original PDFs