Distorted Android

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

// 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.app.ActivityManager;

import android.content.Context;

import android.content.pm.ConfigurationInfo;

import android.opengl.GLSurfaceView;

import android.view.MotionEvent;

class RubikSurfaceView extends GLSurfaceView

{

    private final static int BACK   = 1;  // FRONT ... BOTTOM

    private final static int LEFT   = 2;  //

    private final static int RIGHT  = 3;  //

    private final static int TOP    = 4;  //

    private final static int BOTTOM = 5;  //

    static final int VECTY = 1;  // dont change this

    static final int VECTZ = 2;  //

    private static final int[] VECT = {VECTX,VECTY,VECTZ};

    private float mCameraDistance;

    public RubikSurfaceView(Context context)

      {

      super(context);

      mCamera= new float[3];

      mTouchPointCastOntoFace = new float[3];

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

      mQuatAccumulated = mRenderer.initializeQuat();

      final ConfigurationInfo configurationInfo = activityManager.getDeviceConfigurationInfo();

      setEGLContextClientVersion( (configurationInfo.reqGlEsVersion>>16) >= 3 ? 3:2 );

      setRenderer(mRenderer);

      }

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

    public RubikRenderer getRenderer()

      {

      return mRenderer;

      }

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

    public boolean onTouchEvent(MotionEvent event)

      int action = event.getAction();

      int x = (int)event.getX();

      int y = (int)event.getY();

      switch(action)

         {

                                       mY = y;

                                       mLastTouchedFace = faceTouched(x,y);

                                         {

                                         mQuatCurrent.set(quatFromDrag(mX-x,mY-y));

                                         mRenderer.setQuatCurrent(mQuatCurrent);

                                         }

                                         if( (mX-x)*(mX-x)+(mY-y)*(mY-y)>minimumToRotate )

                                           {

                                         }

                                         {

                                         continueRotation(x,y);

                                         }

                                       mDragging = false;

                                       mQuatCurrent.set(0f, 0f, 0f, 1f);

                                       mRenderer.setQuatCurrent(mQuatCurrent);

                                       mRenderer.setQuatAccumulated(mQuatAccumulated);

         }

      return true;

      }

    void setScreenSize(int width, int height)

      {

      mScreenWidth = width;

      mScreenHeight= height;

      mScreenMin = width<height ? width:height;

      }

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

    void recomputeCameraDistance(double fovInRadians)

      {

      mCameraDistance = (float)((mScreenHeight*0.5f)/Math.tan(fovInRadians*0.5));

      }

      convertCameraPointToScreenSpace();

          {

          float qY= (mTouchPointCastOntoFace[1]+cubeHalfSize) / (2*cubeHalfSize);

          float qZ= (mTouchPointCastOntoFace[2]+cubeHalfSize) / (2*cubeHalfSize);

          }

      }

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

    private void addNewRotation(int x, int y)

      {

      float cubeHalfSize= mRenderer.returnCubeSizeInScreenSpace()*0.5f;

      convertTouchPointToScreenSpace(x,y);

      castTouchPointOntoFace(mLastTouchedFace,cubeHalfSize,mDiff);

      mDiff[1] -= mTouchPointCastOntoFace[1];

      mDiff[2] -= mTouchPointCastOntoFace[2];

      int xAxis = retFaceXaxis(mLastTouchedFace);

      int yAxis = retFaceYaxis(mLastTouchedFace);

      mRotationVect = (isVertical( mDiff[xAxis], mDiff[yAxis]) ? VECT[xAxis]:VECT[yAxis]);

      mTouchPoint[1] = mPoint[1];

      mTouchPoint[2] = mPoint[2];

      mCube.addNewRotation(mRotationVect,offset);

    private boolean isVertical(float x, float y)

      {

      return (y>x) ? (y>=-x) : (y< -x);

      }

    private void continueRotation(int x, int y)

      {

      mDiff[1] = mPoint[1]-mTouchPoint[1];

      mDiff[2] = mPoint[2]-mTouchPoint[2];

      int yAxis= retFaceYaxis(mLastTouchedFace);

      int sign = retFaceRotationSign(mLastTouchedFace);

      float angle = (mRotationVect==xAxis ? mDiff[yAxis] : -mDiff[xAxis]);

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

    private void finishRotation()

      {

      mRenderer.finishRotation();

      }

// return quat1*quat2

      float qx = quat1.get1();

      float qy = quat1.get2();

      float qz = quat1.get3();

      float qw = quat1.get4();

      float rx = quat2.get1();

      float ry = quat2.get2();

      float rz = quat2.get3();

      float rw = quat2.get4();

      float tx = rw*qx - rz*qy + ry*qz + rx*qw;

      float ty = rw*qy + rz*qx + ry*qw - rx*qz;

      float tz = rw*qz + rz*qw - ry*qx + rx*qy;

      float tw = rw*qw - rz*qz - ry*qy - rx*qx;

      return new Static4D(tx,ty,tz,tw);

      }

// rotate 'vector' by quat^(-1)  ( i.e. return (quat^-1)*vector*quat )

    static Static4D rotateVectorByInvertedQuat(Static4D vector, Static4D quat)

      {

      float qx = quat.get1();

      float qy = quat.get2();

      float qz = quat.get3();

      float qw = quat.get4();

      Static4D quatInverted= new Static4D(-qx,-qy,-qz,qw);

      Static4D tmp = quatMultiply(quatInverted,vector);

      return quatMultiply(tmp,quat);

      }

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

// rotate 'vector' by quat  ( i.e. return quat*vector*(quat^-1) )

    static Static4D rotateVectorByQuat(Static4D vector, Static4D quat)

      {

      float qx = quat.get1();

      float qy = quat.get2();

      float qz = quat.get3();

      float qw = quat.get4();

      Static4D quatInverted= new Static4D(-qx,-qy,-qz,qw);

      Static4D tmp = quatMultiply(quat,vector);

      return quatMultiply(tmp,quatInverted);

      }

    private Static4D quatFromDrag(float dragX, float dragY)

      {

      float axisX = dragY;  // inverted X and Y - rotation axis is

      float axisL = (float)Math.sqrt(axisX*axisX + axisY*axisY + axisZ*axisZ);

      if( axisL>0 )

        {

        axisX /= axisL;

        axisY /= axisL;

        axisZ /= axisL;

        return new Static4D(axisX*sinA, axisY*sinA, axisZ*sinA, cosA);

        }

      return new Static4D(0f, 0f, 0f, 1f);

      }

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

      int zAxis= retFaceZaxis(face);

      {

      float halfScrWidth  = mScreenWidth *0.5f;

      float halfScrHeight = mScreenHeight*0.5f;

      Static4D touchPoint = new Static4D(x-halfScrWidth, halfScrHeight-y, 0, 0);

      Static4D rotatedTouchPoint= rotateVectorByInvertedQuat(touchPoint, mQuatAccumulated);

      mPoint[1] = rotatedTouchPoint.get2();

      mPoint[2] = rotatedTouchPoint.get3();

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

      Static4D rotatedCamera= rotateVectorByInvertedQuat(cameraPoint, mQuatAccumulated);

      mCamera[1] = rotatedCamera.get2();

      mCamera[2] = rotatedCamera.get3();

// given precomputed mCam and mPoi, respectively camera and touch point positions in ScreenSpace,

// cast this touch point onto the 'face' and write the cast coords to 'output'.

// Center of the 'face' = (0,0)

      {

      int sign = retFaceSign(face);

      int zAxis= retFaceZaxis(face);

      output[1] = (mPoint[1]-mCamera[1])*ratio + mCamera[1];

      output[2] = (mPoint[2]-mCamera[2])*ratio + mCamera[2];

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

      }

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

      {

      return (face==BACK || face==RIGHT || face==TOP) ? 1:-1;

        {

        case FRONT :

        case BACK  : return VECTX;

        case LEFT  :

        case RIGHT : return VECTZ;

        case TOP   :

        case BOTTOM: return VECTX;

        }

      switch(face)

        {

        case BACK  : return VECTY;

        case LEFT  :

        case RIGHT : return VECTY;

        case TOP   :

        case BOTTOM: return VECTZ;

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

      switch(face)

        {

        case FRONT :