Magic Cube

///////////////////////////////////////////////////////////////////////////////////////////////////

// Copyright 2019 Leszek Koltunski                                                               //

//                                                                                               //

// This file is part of Distorted.                                                               //

//                                                                                               //

// Distorted is free software: you can redistribute it and/or modify                             //

// it under the terms of the GNU General Public License as published by                          //

// the Free Software Foundation, either version 2 of the License, or                             //

// (at your option) any later version.                                                           //

//                                                                                               //

// Distorted is distributed in the hope that it will be useful,                                  //

// but WITHOUT ANY WARRANTY; without even the implied warranty of                                //

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the                                 //

// GNU General Public License for more details.                                                  //

//                                                                                               //

// You should have received a copy of the GNU General Public License                             //

// along with Distorted.  If not, see <http://www.gnu.org/licenses/>.                            //

///////////////////////////////////////////////////////////////////////////////////////////////////

package org.distorted.magic;

import android.opengl.GLSurfaceView;

import org.distorted.effect.TransitionEffect;

import org.distorted.library.effect.EffectType;

import org.distorted.library.effect.VertexEffectSink;

import org.distorted.library.main.DistortedEffects;

import org.distorted.library.main.DistortedLibrary;

import org.distorted.library.main.DistortedScreen;

import org.distorted.library.main.DistortedTexture;

import org.distorted.library.mesh.MeshQuad;

import org.distorted.library.message.EffectListener;

import org.distorted.library.message.EffectMessage;

import org.distorted.library.type.Static4D;

import javax.microedition.khronos.egl.EGLConfig;

import javax.microedition.khronos.opengles.GL10;

///////////////////////////////////////////////////////////////////////////////////////////////////

public class RubikRenderer implements GLSurfaceView.Renderer, EffectListener

{

    private static final float CUBE_SCREEN_RATIO = 0.5f;

    private static final float CAMERA_DISTANCE   = 0.6f;  // 0.6 of the length of max(scrHeight,scrWidth)

    public  static final int TEXTURE_SIZE = 600;

    private RubikSurfaceView mView;

    private DistortedScreen mScreen;

    private Static4D mQuatCurrent, mQuatAccumulated;

    private Static4D mTempCurrent, mTempAccumulated;

    private float mCubeSizeInScreenSpace;

    private int mNextCubeSize;

    private long mRotationFinishedID, mTransitionEffectID;

    private boolean mFinishRotation, mRemoveRotation, mFinishDragCurrent, mFinishDragAccumulated;

    private boolean mCanRotate, mCanDrag;

    private RubikCube mOldCube, mNewCube;

    private int mScreenWidth, mScreenHeight;

    private MeshQuad mMesh;

///////////////////////////////////////////////////////////////////////////////////////////////////

    RubikRenderer(RubikSurfaceView v)

      {

      mView = v;

      mScreen = new DistortedScreen();

      mOldCube = null;

      mNewCube = null;

      mTempCurrent     = new Static4D(0,0,0,1);

      mTempAccumulated = initializeQuat();

      mQuatCurrent     = new Static4D(0,0,0,1);

      mQuatAccumulated = initializeQuat();

      mScreenWidth = mScreenHeight = 0;

      mFinishRotation        = false;

      mRemoveRotation        = false;

      mFinishDragCurrent     = false;

      mFinishDragAccumulated = false;

      mNextCubeSize= 0;

      mCanRotate = true;

      mCanDrag   = true;

      mMesh= new MeshQuad();

      }

///////////////////////////////////////////////////////////////////////////////////////////////////

// various things are done here delayed, 'after the next render' as not to be done mid-render and

// cause artifacts.

    public void onDrawFrame(GL10 glUnused) 

      {

      mScreen.render( System.currentTimeMillis() );

      if( mFinishDragCurrent )

        {

        mFinishDragCurrent = false;

        mQuatCurrent.set(mTempCurrent);

        }

      if( mFinishDragAccumulated )

        {

        mFinishDragAccumulated = false;

        mQuatAccumulated.set(mTempAccumulated);

        }

      if( mFinishRotation )

        {

        mCanRotate = false;

        mFinishRotation=false;

        mRotationFinishedID = mNewCube.finishRotationNow(this);

        }

      if( mRemoveRotation )

        {

        mRemoveRotation=false;

        mNewCube.removeRotationNow(this);

        mCanRotate = true;

        }

      if( mNextCubeSize!=0 )

        {

        mCanDrag   = false;

        mCanRotate = false;

        createCubeNow(mNextCubeSize);

        try

          {

          TransitionEffect effect = TransitionEffect.create(TransitionEffect.Type.ROUND);

          mTransitionEffectID = effect.start(mScreen,mOldCube,mNewCube,this);

          }

        catch(Exception ex)

          {

          android.util.Log.e("Renderer", "failed to create TransitionEffect, exception: "+ex.getMessage());

          }

        mNextCubeSize = 0;

        }

      }

///////////////////////////////////////////////////////////////////////////////////////////////////

// EffectListener. The library sends a message to us when it's time to call 'removeRotation'

   public void effectMessage(final EffectMessage em, final long effectID, final long objectID)

     {

     if(      effectID == mRotationFinishedID )

       {

       //android.util.Log.e("renderer", "rotation finished");

       mRemoveRotation = true;

       }

     else if( effectID == mTransitionEffectID )

       {

       /*

       int nM = mNewCube.getNumEffects(EffectType.MATRIX);

       int nV = mNewCube.getNumEffects(EffectType.VERTEX);

       int nF = mNewCube.getNumEffects(EffectType.FRAGMENT);

       int nP = mNewCube.getNumEffects(EffectType.POSTPROCESS);

       android.util.Log.d("renderer", "transition finished, new cube effects= "+nM+","+nV+","+nF+","+nP);

       int oM = mOldCube.getNumEffects(EffectType.MATRIX);

       int oV = mOldCube.getNumEffects(EffectType.VERTEX);

       int oF = mOldCube.getNumEffects(EffectType.FRAGMENT);

       int oP = mOldCube.getNumEffects(EffectType.POSTPROCESS);

       android.util.Log.d("renderer", "transition finished, old cube effects= "+oM+","+oV+","+oF+","+oP);

       */

       mCanRotate = true;

       mCanDrag   = true;

       }

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

    public void onSurfaceChanged(GL10 glUnused, int width, int height) 

      {

      float cameraDistance = CAMERA_DISTANCE*(width>height ? width:height);

      float fovInDegrees   = computeFOV(cameraDistance,height);

      mScreen.setProjection( fovInDegrees, 0.1f);

      mView.setScreenSize(width,height);

      mView.setCameraDist(cameraDistance);

      mScreen.resize(width, height);

      recomputeScaleFactor(width,height);

      mScreenHeight = height;

      mScreenWidth  = width;

      }

///////////////////////////////////////////////////////////////////////////////////////////////////

    public void onSurfaceCreated(GL10 glUnused, EGLConfig config) 

      {

      mNewCube.createTexture();

      mScreen.detachAll();

      mScreen.attach(mNewCube);

      VertexEffectSink.enable();

      TransitionEffect.enableEffects();

      try

        {

        DistortedLibrary.onCreate(mView.getContext());

        }

      catch(Exception ex)

        {

        android.util.Log.e("Rubik", ex.getMessage() );

        }

      }

///////////////////////////////////////////////////////////////////////////////////////////////////

   private float computeFOV(float cameraDistance, int screenHeight)

     {

     double halfFOVInRadians = Math.atan( screenHeight/(2*cameraDistance) );

     return (float)(2*halfFOVInRadians*(180/Math.PI));

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

// no this will not race with onDrawFrame

   void finishRotation()

     {

     mFinishRotation = true;

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

   boolean createCube(int newSize)

     {

     if( mCanDrag && mCanRotate )

       {

       mNextCubeSize = newSize;

       return true;

       }

     android.util.Log.e("renderer", "cannot change, drag="+mCanDrag+" rotate="+mCanRotate);

     return false;

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

   void createCubeNow(int newSize)

     {

     int oldSize = mNewCube==null ? 0 : mNewCube.getSize();

     if( oldSize!=newSize )

       {

       if( mOldCube!=null ) mOldCube.releaseResources();

       mOldCube = mNewCube;

       DistortedTexture texture = new DistortedTexture(TEXTURE_SIZE,TEXTURE_SIZE);

       DistortedEffects effects = new DistortedEffects();

       mNewCube = new RubikCube(newSize, mQuatCurrent, mQuatAccumulated, texture, mMesh, effects);

       mNewCube.createTexture();

       if( mScreenWidth!=0 )

         {

         recomputeScaleFactor(mScreenWidth,mScreenHeight);

         }

       }

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

   private void recomputeScaleFactor(int screenWidth, int screenHeight)

     {

     mCubeSizeInScreenSpace = CUBE_SCREEN_RATIO*(screenWidth>screenHeight ? screenHeight:screenWidth);

     mNewCube.recomputeScaleFactor(screenWidth, screenHeight, mCubeSizeInScreenSpace);

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

   void scrambleCube()

     {

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

   float returnCubeSizeInScreenSpace()

     {

     return mCubeSizeInScreenSpace;

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

   boolean canRotate()

     {

     return mCanRotate;

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

   boolean canDrag()

     {

     return mCanDrag;

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

   RubikCube getCube()

     {

     return mNewCube;

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

// Initial rotation of the cube. Something semi-random that looks good.

   Static4D initializeQuat()

     {

     return new Static4D(-0.25189602f,0.3546389f,0.009657208f,0.90038127f);

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

   void setQuatCurrent(Static4D current)

     {

     mTempCurrent.set(current);

     mFinishDragCurrent = true;

     }

///////////////////////////////////////////////////////////////////////////////////////////////////

   void setQuatAccumulated(Static4D accumulated)

     {

     mTempAccumulated.set(accumulated);

     mFinishDragAccumulated = true;

     }

}