used to avoid dual update traversals of the scene, which is not
allowed in my application (but I forgot the reason ;-) Now the blank
problem will disappear.
Inactive mode is also available, using the --inactive mode and
--camera-eye and --camera-hpr to set camera position:
./osgposter --output-poster --poster output.bmp --tilesize 800 600
--finalsize 8000 6000 cow.osg --inactive --camera-eye 0 0 20
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I uses a queue of Camera objects to do offscreen rendering with the Camera::attach() function. The entire picture is split into many tiles and it will take a few seconds while attaching and detaching cameras with tiles. You may select to output every tile as an image file, or combine them together to create a large poster, for example, a 12800 x 9600 image.
Start the program like this:
./osgposter --output-poster --poster output.bmp --tilesize 800 600 --finalsize 8000 6000 cow.osg
Adjust the scene camera to a suitable position and press 'p' or 'P' on the keyboard. Wait until sub-cameras dispatching is finished. And the poster file will be created while closing window. A 8000 x 6000 output.bmp will be created to show a fine-printed cow. :)
The command below may also help:
./osgposter --help
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