Using AppSettings.setSamples() with a value not supported by video hardware causes exception

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What steps will reproduce the problem?
1. Call AppSettings.setSamples(23940293) before starting the jME3 app.

What is the expected output? What do you see instead?
I expect jME3 to check maximum number of supported samples and set that value 
on the context. Currently, the context simply fails to load.

Original issue reported on code.google.com by ShadowIs...@gmail.com on 9 Jun 2012 at 8:59

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NOTE: This issue will only happen in the case that the main framebuffer has 
been requested to be multisampled. When using post processing, the user will 
typically set the number of samples in the FrameBuffer itself, which would 
properly be clamped to prevent a crash in the renderer. Most users reporting 
this issue set the "x16" option unwittingly in jME3's built-in settings dialog, 
then rush to the forum to report the crash. 

Possible solution: Create new method in LwjglContext

int determineMaxSamples() which would create a pbuffer context and then query 
the max number of samples by using GL_EXT_framebuffer_multisample and 
GL_MAX_SAMPLES. 
Unfortunately, this extension was released quite recently and therefore might 
not be supported in older GPUs. The only solution is to test each number of 
samples, starting at AppSettings.getSamples() and dividing by 2 each time, e.g. 
16, 8, 4, 2, 1, until the pbuffer creation no longer throws an exception. 
However, the GPU may not support pbuffer creation, adding an additional 
handicap to this method. If pbuffers are not supported, then we have two 
options, either return 1, indicating that multisampling is not available, or 
return MAX_INT, indicating any value is acceptable and let the user take the 
risk of an exception. Since jMonkeyPlatform utilizes pbuffers extensively, we 
can conclude that this method will succeed in the majority of cases given there 
were no reports of jMP failing to load due to lack of pbuffer support.

Original comment by ShadowIs...@gmail.com on 4 Aug 2012 at 4:55

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Original comment by ShadowIs...@gmail.com on 4 Aug 2012 at 9:52

• Changed state: Fixed
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