How to display a text?

[woshidag]

I want to display a text in smartGLView. How can I achieve this ?

[smart-fun]

Hello woshidag and thank you for using smartGL.

There are 2 ways to do this, the first one is without smartGL ^^ If you just want a 2D text on top of the surface, then you'd better to add a TextView on top of the SmartGLView (both in the same RelativeLayout for example)

The other way is using a Texture with a text in it, and then use that texture in a sprite or a 3D Object. To create that texture you'll need to draw the text in a bitmap. Here is an example on how to draw a text in a bitmap:

private Bitmap createBitmapFromText(String text) {
    Paint paint = new Paint();
    paint.setAntiAlias(true);
    paint.setTextSize(20);
    paint.setColor(0xFF112233);
    Rect bounds = new Rect();
    paint.getTextBounds(text, 0, text.length(), bounds);
    int width = bounds.right - bounds.left;
    int height = bounds.bottom - bounds.top;
    Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
    if (bitmap != null) {
        Canvas canvas = new Canvas(bitmap);
        canvas.drawColor(0xFFdd8833);
        canvas.drawText(text, -bounds.left, -bounds.top, paint);
    }
    return bitmap;
}

then to create the texture and use it in a sprite:

Bitmap bitmapText = createBitmapFromText("Hello World");
if (bitmapText != null) {
    Texture texture = new Texture(bitmapText);
    mySprite.setTexture(texture);
}

Note that you don't have (must not) create the bitmap or texture at every frame! Create it once and use it. If you have several texts to write, I recommend to use one big texture and change UVs to split the Texture to be used by several faces (but this is another topic).

Arnaud.

[woshidag]

thank you.i use smartgl to show my robot's 2d map and robot pose.