Flip layer

[Pongpipat Supalak]

How to flip layer.
Give me for example code please.

[Michael Bayne]

On Tue, Apr 14, 2015 at 8:35 AM, Pongpipat Supalak <k.blu...@gmail.com> wrote:

How to flip layer.
Give me for example code please.

If by that you mean animate a layer flipping over using a 3D rotation, then you need code that looks something like this:

https://github.com/threerings/tripleplay/blob/twodotoh/core/src/main/java/tripleplay/ui/Box.java

Specifically the flip transition:

    public static class Flip extends Trans {

        public Flip (int duration) { super(duration); }

        @Override protected void init () {

            // TODO: compute the location of the center of the box in screen coordinates, place

            // the eye there in [0, 1] coords

            Graphics gfx = _ocontents.root().iface.plat.graphics();

            Point eye = LayerUtil.layerToScreen(

                _ocontents.layer, _ocontents.size().width()/2, _ocontents.size().height()/2);

            eye.x /= gfx.viewSize.width();

            eye.y /= gfx.viewSize.height();

            _obatch = new RotateYBatch(gfx.gl, eye.x, eye.y, 1);

            _nbatch = new RotateYBatch(gfx.gl, eye.x, eye.y, 1);

            _ocontents.layer.setBatch(_obatch);

            _ncontents.layer.setBatch(_nbatch);

        }

        @Override protected void update (float pct) {

            _obatch.angle = FloatMath.PI * pct;

            _nbatch.angle = -FloatMath.PI * (1-pct);

            _ocontents.layer.setVisible(pct < 0.5f);

            _ncontents.layer.setVisible(pct >= 0.5f);

        }

        @Override protected void cleanup () {

            _ocontents.layer.setBatch(null);

            _ncontents.layer.setBatch(null);

        }

        protected RotateYBatch _obatch, _nbatch;

    }

This is operating on TPUI elements, but those are just a Layer with a bunch of extra bookkeeping. So all of this operates on the underlying layers and should be pretty easy to convert to whatever you're doing.

-- m...@samskivert.com