openframeworks / openframeworks/openFrameworks

ofAppEGLWindow - cursor texture is subject to gl transformations in some cases

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bug linuxarm
Dominant language
C++
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Description

On the Raspberry Pi (which uses ofAppEGLWindow) ...

If matrix transformation calls (e.g. ofRotate, ofTranslate) are not wrapped in a ofPushMatrix() and an ofPopMatrix(), the home-brew cursor texture will become subject to the global transformation stack.

@arturoc got any ideas? I think this may have something to do with not pushing the default shader each pass on the Pi.

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First steps

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  3. Fork the repository and make your change on a branch.
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Research direction

Start by locating the ofAppEGLWindow implementation and trace how the home-brew cursor texture is drawn after ofRotate or ofTranslate calls. Compare the cursor rendering with and without ofPushMatrix() and ofPopMatrix(), then investigate whether the default shader state is restored on each pass. Done means global transformations no longer affect the cursor on Raspberry Pi.

Written by the indexing model from the issue text.

Assessment

Tech stack
cpp, raspberry-pi
Domain
computer-graphics, embedded-iot
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
25/100

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