Distorted Android

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

// 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.examples.rubik;

import android.opengl.GLSurfaceView;

import org.distorted.library.effect.VertexEffectSink;

import org.distorted.library.main.Distorted;

import org.distorted.library.main.DistortedScreen;

import org.distorted.library.message.EffectListener;

import org.distorted.library.message.EffectMessage;

import org.distorted.library.type.Static3D;

import org.distorted.library.type.Static4D;

import javax.microedition.khronos.egl.EGLConfig;

import javax.microedition.khronos.opengles.GL10;

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

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)

    private RubikSurfaceView mView;

    private DistortedScreen mScreen;

    private Static3D mMove, mScale;

    private Static4D mQuatCurrent, mQuatAccumulated;

    private Static4D mTempCurrent, mTempAccumulated;

    private float mCubeSizeInScreenSpace;

    private int mNextCubeSize;

    private boolean mFinishRotation, mRemoveRotation, mFinishDragCurrent, mFinishDragAccumulated;

    private boolean mCanRotate;

    private RubikCube mCube;

    private int mScreenWidth, mScreenHeight;

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

    RubikRenderer(RubikSurfaceView v)

      {

      mView = v;

      mScreen = new DistortedScreen();

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

      mTempAccumulated = initializeQuat();

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

      mQuatAccumulated = initializeQuat();

      mScreenWidth = mScreenHeight = 0;

      mMove  = new Static3D(0,0,0);

      mScale = new Static3D(1,1,1);

      mFinishRotation        = false;

      mRemoveRotation        = false;

      mFinishDragCurrent     = false;

      mFinishDragAccumulated = false;

      mNextCubeSize= 0;

      mCanRotate = true;

      }

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

// 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;

        mCube.finishRotationNow(this);

        }

      if( mRemoveRotation )

        {

        mRemoveRotation=false;

        mCube.removeRotationNow(this);

        mCanRotate = true;

        }

      if( mNextCubeSize!=0 )

        {

        createCubeNow(mNextCubeSize);

        mScreen.detachAll();

        mCube.attachToScreen(mScreen);

        mNextCubeSize = 0;

        mCanRotate = true;   // it can happen that we have just changed the size of the cube while

                             // finishing rotation and never removed it!

        }

      }

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

// 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)

     {

     switch(em)

        {

        case EFFECT_FINISHED: mRemoveRotation = true; break;

        }

     }

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

    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) 

      {

      mCube.createTexture();

      mScreen.detachAll();

      mCube.attachToScreen(mScreen);

      VertexEffectSink.enable();

      try

        {

        Distorted.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;

     }

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

   void createCube(int newSize)

     {

     mNextCubeSize = newSize;

     }

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

   void createCubeNow(int newSize)

     {

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

     if( oldSize!=newSize )

       {

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

       mCube = new RubikCube(newSize, mMove, mScale, mQuatCurrent, mQuatAccumulated);

       mCube.createTexture();

       if( mScreenWidth!=0 )

         {

         recomputeScaleFactor(mScreenWidth,mScreenHeight);

         }

       }

     }

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

   private void recomputeScaleFactor(int screenWidth, int screenHeight)

     {

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

     float texSize = mCube.getTextureSize();

     float scaleFactor = mCubeSizeInScreenSpace/(texSize*mCube.getSize());

     mMove.set( (screenWidth-scaleFactor*texSize)/2 , (screenHeight-scaleFactor*texSize)/2 , -scaleFactor*texSize/2 );

     mScale.set(scaleFactor,scaleFactor,scaleFactor);

     }

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

   void scrambleCube()

     {

     }

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

   float returnCubeSizeInScreenSpace()

     {

     return mCubeSizeInScreenSpace;

     }

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

   boolean canRotate()

     {

     return mCanRotate;

     }

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

   RubikCube getCube()

     {

     return mCube;

     }

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

// 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;

     }

}