Modify alpha value of specific pixels of customized widget

[Chandan Bhatia1]

Hello, I am using customized widget in my project. I get buffer index using below:

*framebuffer = touchgfx::HAL::getInstance()->lockFrameBuffer();

 

In this  customized widget, I want to set few pixels alpha value as 0 so it can be transparent and back ground can be visible.

Any suggestions?

Thanks

[Martin KJELDSEN]

You could turn this into a generic widget that you can place on top of things and configure to do something with the pixels below: 1x1 or 10x10, set alpha value, blend with other color, etc.

/Martin

[Chandan Bhatia1]

@Martin KJELDSEN​  Sorry I didn't get it. How should I set alpha value ? I am setting value of pixel as below image for custom widget.

 

 

Thanks

[Martin KJELDSEN]

I think you should read some general material on how to modify pixels, like blending and applying alpha values. You're doing it in the right place, TouchGFX wise.

/Martin

[Chandan Bhatia1]

@Martin KJELDSEN​  Can you please share links ?

[Martin KJELDSEN]

There's lots of information online, just do some searching. It's pretty standard - Basically you seperate the red, green and blue values from the pixel and apply your alpha, then combine the values.,