Bug report #8209: Print as raster doesn't work on OsX - QGIS Application - QGIS Issue Tracking

Bug report #8209

Print as raster doesn't work on OsX

Added by rcline - almost 11 years ago. Updated about 5 years ago.

Status:	Closed
Priority:	Normal
Assignee:	-
Category:	Map Composer/Printing
Affected QGIS version:	2.4.0	Regression?:	No
Operating System:	OS X	Easy fix?:	No
Pull Request or Patch supplied:	No	Resolution:	end of life
Crashes QGIS or corrupts data:	No	Copied to github as #:	17024

Description

If print as raster is selected and set to 72 dpi, then the map is scaled correctly but quality is poor. As the dpi is increased, I get a smaller and smaller upper-left corner of the map filling the whole page. At 300 dpi I get about a quarter (length) of the map blown up to fill the whole page. Saving as PDF works correctly. Doesn't appear to be effected by page size.

Printing worked in 1.8 so I set to blocker.

printComposer.png (629 KB) rcline -, 2013-07-03 06:26 AM

printAsRasterOn.pdf (1.61 MB) rcline -, 2013-07-03 06:26 AM

printAsRasterOff.pdf (1.93 MB) rcline -, 2013-07-03 06:26 AM

History

#1 Updated by Nyall Dawson almost 11 years ago

I can't replicate this - can you please share some more details (preferably if you can share your project file here so I can test directly -- failing that a screencast showing the issue would help considerably).

#2 Updated by rcline - almost 11 years ago

File printComposer.png added
File printAsRasterOn.pdf added
File printAsRasterOff.pdf added

If Print as raster is checked in the Composition tab, any project will produce the error including having only a single shapefile loaded. The file printComposer.png shows the settings. If Print as raster is checked, the I get the results in printAsRasterOn.pdf. If it is not selected, then I get the expected results shown in printAsRasterOff.pdf. The problem is also present in QGIS 1.8. It appears I just never used the setting. I was experimenting with blend modes and apparently did not get all the settings reverted. I was getting the Project contains composition effects dialog and accepting its default of Print as raster on. Since the problem is present in 1.8, the priority could be reduces, however this impacts the use of the new blend modes.

#3 Updated by Nyall Dawson almost 11 years ago

Hmm... still can't reproduce this unfortunately. It may be an OSX specific issue...

Just to confirm, which method are you using to create the PDFs? Are you using the "Export as PDF" toolbar button/menu item, or printing the composition to a PDF driver?

#4 Updated by rcline - almost 11 years ago

Using Print in the toolbar and either going directly to a printer or going to the PDF driver in Mac print dialog gives the same results. "Export as PDF" works. Tested "Export as PDF" doing a blend of a DEM and its hill shade. Given there is a good alternative to get quality output when doing blends, I would not consider the problem a blocker at this point.

#5 Updated by Giovanni Manghi almost 11 years ago

Status changed from Open to Feedback

rcline - wrote:

Using Print in the toolbar and either going directly to a printer or going to the PDF driver in Mac print dialog gives the same results. "Export as PDF" works. Tested "Export as PDF" doing a blend of a DEM and its hill shade. Given there is a good alternative to get quality output when doing blends, I would not consider the problem a blocker at this point.

have you testes another OS, just to exclude a OS-specific bug? thanks.

#6 Updated by rcline - almost 11 years ago

Only able to test with OS X.

#7 Updated by Giovanni Manghi almost 11 years ago

rcline - wrote:

Only able to test with OS X.

then please share a project (and data) to allow us try in other OSes.

#8 Updated by rcline - almost 11 years ago

If "Print as raster" is selected, the Mac print driver assumes that the raster has a resolution of 72 dpi, no matter to what value the export resolution is set. If export resolution is set to 72 dpi the the map will print correctly (exact area as seen in print composer). If the export resolution is set to 300 dpi and in page setup the scale is set to 24% (72/300) the map prints correctly. If the export resolution is set to 600 dpi and in page setup the scale is set to 12% (72/600) the map prints correctly.

It would appear that rasters resolution defined by"Export resolution" is not getting passed correctly to the Mac print driver and it defaults to 72 dpi so it prints the upper-left corner of what it thinks is a very large low resolution raster.

The problem is not project or data related. I can start QGIS, open a new print composer, draw a rectangle, and click the check box for "Print as raster" and reproduce the problem. I have not even used "Add new map".