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.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

{

    private static final int NUM_CUBES = 4;

    private static final float CUBE_SCREEN_RATIO = 0.5f;

    private static final float CAMERA_DISTANCE = 0.5f;     // 0.5 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 boolean mFinishRotation, mFinishDragCurrent, mFinishDragAccumulated;

    private RubikCube mCube;

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

    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();

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

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

      mFinishRotation        = false;

      mFinishDragCurrent     = false;

      mFinishDragAccumulated = false;

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

      }

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

    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 )

        {

        mFinishRotation=false;

        mCube.finishRotationCalledOnNextRender();

        }

      }

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

    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);

      mCubeSizeInScreenSpace = CUBE_SCREEN_RATIO*(width>height ? height:width);

      float texSize = mCube.getTextureSize();

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

      mMove.set( (width-scaleFactor*texSize)/2 , (height-scaleFactor*texSize)/2 , -scaleFactor*texSize/2 );

      mScale.set(scaleFactor,scaleFactor,scaleFactor);

      mScreen.resize(width, height);

      }

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

    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) );

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

      return fovInDegrees;

      }

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

// no this will not race with onDrawFrame

    void finishRotation()

      {

      mFinishRotation = true;

      }

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

    float returnCubeSizeInScreenSpace()

      {

      return mCubeSizeInScreenSpace;

      }

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

    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;

      }

}