Read pixel color from screen for a given coordinate.

[solewalker]

I wanted to read pixel color either RGB or Hex from the screen for a point inside game window. This could be either a mouse coordinate or a FlxPoint. I searched for a while but could not found anything on this topic. I am not talking about reading pixels off the screen for making a bitmap or sprite. So I need color for one pixel not a given rect inside the screen. Like sorta this,

var pixColor = ReadPixelFromScreen(x, y);  // x, y is a coordinate on the screen

[Gama11]

On Flash or HTML5, you can access the camera buffer for this:

FlxG.camera.buffer.getPixel(x, y);

That is, if you don't have any additional cameras / messed with the camera positioning.

[solewalker]

So it does not work on native? I am yet to try the code, as I am not at my home right now.

[Gama11]

Yep, no camera buffer in FLX_RENDER_TILE mode. There's no reliable way to get a BitmapData with the screen contents on native I know of.

[solewalker]

This is more of a openfl thing, I see they have implemented the function in development version of lime, so I would try to use dev lime, if it does not break flixel or other things.

[Gama11]

No, it's not. Which function do you mean? getPixel()? That's always been part of OpenFL's BitmapData, the problem is that FlxG.camera has no buffer BitmapData on native targets.

[solewalker]

I am talking about GL.readPixels http://www.openfl.org/forums/#!/programming:how-to-use-glreadpixels-

This is the way I used to read pixel in pre-shader opengl  or without using any shader code.