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Android canvas.scale (-1,1)

So, my goal is to flip the image horizontally and then draw it on the canvas. I am currently using canvas.scale (-1,1), which works efficiently and draws the image horizontally, however it also screws with x axis values, where the x position will be 150 before the scale, and after I have to switch to -150 for rendering in the same place.

My question is, how can I make the x value be 150 in both cases without having to adjust the x position after the scale? Is there a more efficient way to do this without clicking on performance?

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3 answers

, :

public void applyMatrix(Matrix matrix) {
    mBitmap = Bitmap.createBitmap(mBitmap, 0, 0, 
      mBitmap.getWidth(), mBitmap.getHeight(), matrix, true);
}
...
Matrix matrix = new Matrix();
matrix.preScale(-1, 1);
mSprite.applyMatrix(matrix);
+1

, , . , , ImageButton. , , . onDraw(Canvas) :

@Override
protected void onDraw(final Canvas canvas) {

    // Scale the canvas, offset by its center.
    canvas.scale(-1f, 1f,
        super.getWidth() * 0.5f, super.getHeight() * 0.5f);

    // Draw the button!
    super.onDraw(canvas);
}
+8

Have you tried to repeat canvas.scale(-1, 1)? It will effectively remove the transformation, as two negatives make it positive.

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