How to use overlay transparent layer by Using DRM with GLES on PowerVR SGX544MP2

PowerVR Insider
1

Hi.



I am trying to draw using multiple layers using GLES and DRM.

I am able to simply drawn with GLES for multiple layers.

However, transparent color of the upper layers is not reflected.

A result of the investigation, it was found to be that allows the setting of alpha values for the layer in ‘drmModeObjectSetProperty’.

But I don’t know is should I pass what the argument for setting the alpha value (Object Type, Object ID, Property ID) .

Could you advice me?



Thank you.

ginjoe

2

Hi ginjoe,



I’m not familiar with the DRM framework you are referring to.



I would recommend using our PVRTrace OpenGL ES capture and analysis tool to verify that you are correctly setting the blend mode & associated functions. If your application isn’t setting blend modes correctly, then there may be a bug in the logic of your application or the framework you are using.



Regards,

Joe

3

Hi Joe.



Thank you for your answer.



That tool is great !!

But My question is very elementary question.

I have not been able to yet use even API for setting…



However I was worth having asked you a question just to have been able to know this tool !!

thank you.



ginjoe

4

Hi ginjoe,



If you’re new to OpenGL ES and want to know more about setting blend modes, I would recommend referring to the source code of our SDK’s AlphaBlend Example.

https://github.com/powervr-graphics/Native_SDK/blob/3.4/Examples/Intermediate/AlphaBlend/OGLES2/OGLES2AlphaBlend.cpp



Let us know if there is anything else we can help you with.



Joe