openframeworks / openframeworks/openFrameworks

grabScreen gives black when width equals certain values. FIX may be found

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C++
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Description

I have a strange behavior of grabScreen. I get a black image when width captured = 69 or 70 or 71
But I have the right image when width captured = 67 / 68 / 72 / or more
Some other higher values also gives black.
Height doesn't seem to have an influence

ofImage img
img.clear();
img.grabScreen(0,0,70,100);
img.draw(0,200);

I'm using Head on OSX 10.10.5

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Research direction

Locate the grabScreen implementation and reproduce the issue on OS X using widths 67 through 72 and the other failing values described in the report. Trace the screen-capture path and verify that the resulting images are non-black for the affected widths.

Written by the indexing model from the issue text.

Assessment

Tech stack
cpp
Domain
computer-graphics, desktop
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
25/100

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