How to draw large sized text on a canvas?

Question

I want to draw on canvas month\'s text vertical along screen height.

Paint init:

   this.paint = new Paint();
         


        

Answer 1

I don't have enough reputation to comment on Krylez's excellent answer, but I'd like to reply to mcfly soft's comment/question about paths.

The idea is the same for paths as text. Instead of scaling and translating the canvas a path is drawn on, put the same scaling and translation into a matrix and pass that to Path.transform:

// instead of this:
canvas.scale(sX, sY);
canvas.translate(trX, trY);
canvas.drawPath(path);

// do this:
matrix.postScale(sX, sY);
matrix.postTranslate(trX, trY);
path.transform(matrix);
canvas.drawPath(path);

Answer 2

The problem is that you're drawing text at one size and scaling the result up. Once you've determined how wide you want the text to be, you should use calls to Paint.measureText(), adjusting the size via Paint.setTextSize() accordingly. Once it measures correctly, then you do your call to Canvas.drawText().

An alternative would be to not measure the text at all and just immediately call:

paint.setTextSize(paint.getSize() * scale)

There's no guarantee the text will fit in this case, though.

None of your other transform calls should result in interpolation, so it should give you very sharp lines.

Edit

Here is a code sample and comparison screenshot:

canvas.save();
canvas.scale(10, 10);
canvas.drawText("Hello", 0, 10, mTextPaint);
canvas.restore();
float textSize = mTextPaint.getTextSize();
mTextPaint.setTextSize(textSize * 10);
canvas.drawText("Hello", 0, 300, mTextPaint);
mTextPaint.setTextSize(textSize);