TwistyPuzzleLib

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// Copyright 2021 Leszek Koltunski                                                               //

//                                                                                               //

// This file is part of Magic Cube.                                                              //

//                                                                                               //

// Magic Cube is proprietary software licensed under an EULA which you should have received      //

// along with the code. If not, check https://distorted.org/magic/License-Magic-Cube.html        //

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package org.distorted.objectlib.helpers;

import org.distorted.library.helpers.QuatHelper;

import org.distorted.library.type.Static3D;

import org.distorted.library.type.Static4D;

import org.distorted.objectlib.main.TwistyObject;

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public class ObjectShape

  {

  private static final float[] mTmp1 = new float[4];

  private static final float[] mTmp2 = new float[4];

  private final float[][] mVertices;

  private final int[][] mVertIndices;

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  public ObjectShape(float[][] vertices, int[][] vertIndices)

    {

    mVertices   = vertices;

    mVertIndices= vertIndices;

    }

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  public float[][] getVertices()

    {

    return mVertices;

    }

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  public int[][] getVertIndices()

    {

    return mVertIndices;

    }

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  public static int computeNumComponents(ObjectShape[] shapes)

    {

    int ret = 0;

    for( ObjectShape shape : shapes )

      {

      int numShape = shape.mVertIndices.length;

      if( numShape>ret ) ret = numShape;

      }

    return ret;

    }

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// take vertex, apply quat, apply move, write to output

  private static void computeVertex(float[] output, float[] vertex, float[] move, Static4D quat)

    {

    QuatHelper.rotateVectorByQuat(mTmp2,vertex[0],vertex[1],vertex[2],1.0f,quat);

    int numMoves = move.length/3;

    float moveX=0.0f, moveY=0.0f, moveZ=0.0f;

    for(int m=0; m<numMoves; m++)

      {

      moveX += move[3*m  ];

      moveY += move[3*m+1];

      moveZ += move[3*m+2];

      }

    output[0] = mTmp2[0] + moveX/numMoves;

    output[1] = mTmp2[1] + moveY/numMoves;

    output[2] = mTmp2[2] + moveZ/numMoves;

    }

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  private static boolean vertInFace(float[] vertex, Static3D faceAxis, float dist)

    {

    final float MAX_ERROR = 0.04f;  // Rex Cube requires this

    float x= faceAxis.get0();

    float y= faceAxis.get1();

    float z= faceAxis.get2();

    float a = vertex[0]*x + vertex[1]*y + vertex[2]*z;

    float diff = a - dist;

    return diff>-MAX_ERROR && diff<MAX_ERROR;

    }

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  private static boolean indexContains(int[] indices, int index)

    {

    for( int j : indices )

      if( j==index ) return true;

    return false;

    }

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  private static int[] computeCubitFaceColors(ObjectShape shape, float[] move, Static4D quat, Static3D[] faceAxis, float[] dist3D, float size)

    {

    float[][] vertices = shape.getVertices();

    int[][] indices = shape.getVertIndices();

    int numVert = vertices.length;

    int numFaces = faceAxis.length;

    int numIndices = indices.length;

    int[] cubitFaceColor = new int[numIndices];

    for(int face=0; face<numIndices; face++) cubitFaceColor[face] = 0xffffffff;

    for(int vert=0; vert<numVert; vert++)

      {

      computeVertex(mTmp1,vertices[vert],move,quat);

      int vertBelongsBitmap = 0x00000000;

      for(int face=0; face<numFaces; face++)

        if( vertInFace(mTmp1,faceAxis[face],dist3D[face]*size) ) vertBelongsBitmap |= (1<<face);

      for(int index=0; index<numIndices; index++)

        if( cubitFaceColor[index]!=0 && indexContains(indices[index],vert) ) cubitFaceColor[index] &= vertBelongsBitmap;

      }

    return cubitFaceColor;

    }

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  private static void translateFromBitmap(int cubit, int[] colorsBitmap)

    {

    int len = colorsBitmap.length;

    for(int face=0; face<len; face++)

      {

      if( colorsBitmap[face]==0 ) colorsBitmap[face] = -1;

      else

        {

        int shift=0;

        while( (colorsBitmap[face]&0x1) != 1 )

          {

          colorsBitmap[face]>>=1;

          shift++;

          }

        if( colorsBitmap[face]!=1 )

          {

          android.util.Log.e("D", "ERROR, cubit= "+cubit+" face "+face+" seems to belong to "+shift+" and still "+colorsBitmap[face]);

          }

        colorsBitmap[face] = shift;

        }

      }

    }

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  public static int[][] computeColors(ObjectShape[] shapes, float[][] moves, Static4D[] quats, TwistyObject object)

    {

    int numCubits = moves.length;

    int[][] colors = new int[numCubits][];

    int[] numLayers = object.getNumLayers();

    Static3D[] faceAxis = object.getFaceAxis();

    float[] dist3D = object.getDist3D(numLayers);

    float size = object.getSize();

    for(int cubit=0; cubit<numCubits; cubit++)

      {

      int variant = object.getCubitVariant(cubit,numLayers);

      colors[cubit] = computeCubitFaceColors(shapes[variant],moves[cubit],quats[cubit],faceAxis,dist3D,size);

      translateFromBitmap(cubit,colors[cubit]);

      }

    return colors;

    }

  }