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I'm trying to get the XY coordinates of the pixels in a string in Java, but I can't figure out how.

I'll try to explain more clearly.

Let's say I want to do something like this:

paint.setTextSize(40);
canvas.drawText("hello", 100, 100, paint);

But instead of actually drawing that text, I want a list of coordinates corresponding to all the pixels that would be in that text, which can be relative to the beginning of the text or the canvas, doesn't matter.

Is this at all possible? Can't find anything about it with Google.

Thanks.

Jarrod
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Suffick
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    what have you tried? Did you try the naive solution? Cause you could just make a copy of the canvas, put your text there and compare the pixels - the ones that differ are from your text. This would be VERY slow, obviously. Why do you even need this? – K.L. Oct 05 '12 at 07:25

2 Answers2

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I doubt whether is is even possible without great effort.

For one this depends on what font you are using.

The only way I can imagine it, is by drawing the text internally on a BufferedImage and then check each pixel for its color.

Say, draw it on a white background with black text color.

Pseudo code:

for each pixel row{
    for each pixel column{
        if(pixel.getColor() == (new Color()).black)
           save coordinates
    }
}
LuigiEdlCarno
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  • I got it working pretty well, forgot to mention it's for Android so I have to use Bitmap instead of BufferedImage. Thanks. – Suffick Oct 05 '12 at 09:06
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I think this sdhould answer your question: Calculate text size according to width of text area

You can determine text sizes, but indivudual pixels are dependding of typeface and parameters like weight etc.

In case you need boundaries of individual characters, you can work with substrings

Community
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Konstantin Pribluda
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