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library / src / main / java / org / distorted / library / Distorted.java @ a56bc359

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///////////////////////////////////////////////////////////////////////////////////////////////////
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// Copyright 2016 Leszek Koltunski                                                               //
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//                                                                                               //
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// This file is part of Distorted.                                                               //
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//                                                                                               //
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// Distorted is free software: you can redistribute it and/or modify                             //
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// it under the terms of the GNU General Public License as published by                          //
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// the Free Software Foundation, either version 2 of the License, or                             //
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// (at your option) any later version.                                                           //
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//                                                                                               //
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// Distorted is distributed in the hope that it will be useful,                                  //
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// but WITHOUT ANY WARRANTY; without even the implied warranty of                                //
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the                                 //
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// GNU General Public License for more details.                                                  //
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//                                                                                               //
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// You should have received a copy of the GNU General Public License                             //
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// along with Distorted.  If not, see <http://www.gnu.org/licenses/>.                            //
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///////////////////////////////////////////////////////////////////////////////////////////////////
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package org.distorted.library;
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import java.io.BufferedReader;
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import java.io.IOException;
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import java.io.InputStream;
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import java.io.InputStreamReader;
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import android.content.Context;
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import android.opengl.GLES20;
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import android.os.Build;
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import android.util.Log;
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import org.distorted.library.exception.*;
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
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 * A singleton class used to control various global settings.
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 */
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public class Distorted 
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  {
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  /**
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   * When creating an instance of a DistortedObject from another instance, do not clone anything.
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   * Used in the copy constructor.
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   */
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  public static final int CLONE_NOTHING = 0x0;
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  /**
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   * When creating an instance of a DistortedObject from another instance, clone the Bitmap that's
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   * backing up our DistortedObject. 
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   * <p>
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   * This way we can have two DistortedObjects, both backed up by the same Bitmap, to which we can 
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   * apply different effects. Used in the copy constructor.
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   */
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  public static final int CLONE_BITMAP  = 0x1;
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  /**
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   * When creating an instance of a DistortedObject from another instance, clone the Matrix Effects.
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   * <p>
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   * This way we can have two different DistortedObjects with different Bitmaps behind them, both 
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   * always displayed in exactly the same place on the screen. Applying any matrix-based effect to 
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   * one of them automatically applies the effect to the other. Used in the copy constructor.
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   */
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  public static final int CLONE_MATRIX = 0x2;
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  /**
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   * When creating an instance of a DistortedObject from another instance, clone the Vertex Effects.
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   * <p>
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   * This way we can have two different DistortedObjects with different Bitmaps behind them, both 
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   * always with the same Vertex effects. Applying any vertex-based effect to one of them automatically 
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   * applies the effect to the other. Used in the copy constructor.
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   */
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  public static final int CLONE_VERTEX  = 0x4;
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  /**
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   * When creating an instance of a DistortedObject from another instance, clone the Fragment Effects.
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   * <p>
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   * This way we can have two different DistortedObjects with different Bitmaps behind them, both 
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   * always with the same Fragment effects. Applying any fragment-based effect to one of them automatically 
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   * applies the effect to the other. Used in the copy constructor.
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   */
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  public static final int CLONE_FRAGMENT= 0x8;
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  /**
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   * When creating an instance of a DistortedNode from another instance, clone the children Nodes.
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   * <p>
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   * This is mainly useful for creating many similar sub-trees of Bitmaps and rendering then at different places
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   * on the screen, with (optionally) different effects of the top-level root Bitmap.   
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   */
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  public static final int CLONE_CHILDREN= 0x10;
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  private static final String TAG = Distorted.class.getSimpleName();
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  private static boolean mInitialized = false;
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  private static int mProgramH;         // handle to our shading program.
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  private static int mTextureUniformH;  // the texture.
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  static int mPositionH;                // model position information
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  static int mNormalH;                  // model normal information.
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  static int mTextureCoordH;            // model texture coordinate information.
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  static DistortedFramebuffer mFramebuffer = new DistortedFramebuffer(0); // output to the screen
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///////////////////////////////////////////////////////////////////////////////////////////////////
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  private Distorted()
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    {
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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  private static void sanitizeMaxValues() throws VertexUniformsException,FragmentUniformsException
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    {
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    int maxV,maxF;  
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    int[] param = new int[1];
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    GLES20.glGetIntegerv(GLES20.GL_MAX_VERTEX_UNIFORM_VECTORS, param, 0);
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    maxV = param[0];
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    GLES20.glGetIntegerv(GLES20.GL_MAX_FRAGMENT_UNIFORM_VECTORS, param, 0);
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    maxF = param[0];
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    Log.d(TAG, "Max vectors in vertex shader: "+maxV);
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    Log.d(TAG, "Max vectors in fragment shader: "+maxF);
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    if( !Build.FINGERPRINT.contains("generic") )
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      {
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      int realMaxV = (maxV-11)/4;   // adjust this in case of changes to the shaders...
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      int realMaxF = (maxF- 2)/4;   //
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      if( getMaxVertex()   > realMaxV )
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        {
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        throw new VertexUniformsException("Too many effects in the vertex shader, max is "+realMaxV, realMaxV);
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        }
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      if( getMaxFragment() > realMaxF )
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        {
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        throw new FragmentUniformsException("Too many effects in the fragment shader, max is "+realMaxF, realMaxF);
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        }
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      }
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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  private static int compileShader(final int shaderType, final String shaderSource) throws FragmentCompilationException,VertexCompilationException
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    {
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    int shaderHandle = GLES20.glCreateShader(shaderType);
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    if (shaderHandle != 0) 
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      {
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      GLES20.glShaderSource(shaderHandle, "#version 100 \n"+ generateShaderHeader(shaderType) + shaderSource);
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      GLES20.glCompileShader(shaderHandle);
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      final int[] compileStatus = new int[1];
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      GLES20.glGetShaderiv(shaderHandle, GLES20.GL_COMPILE_STATUS, compileStatus, 0);
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      if (compileStatus[0] != GLES20.GL_TRUE ) 
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        {
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        GLES20.glDeleteShader(shaderHandle);
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        shaderHandle = 0;
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        }
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      }
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    if (shaderHandle == 0)
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      {     
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      String error = GLES20.glGetShaderInfoLog(shaderHandle);
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      switch(shaderType)
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        {
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        case GLES20.GL_VERTEX_SHADER  : throw new VertexCompilationException(error); 
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        case GLES20.GL_FRAGMENT_SHADER: throw new FragmentCompilationException(error);
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        default                       : throw new RuntimeException(error);
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        }
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      }
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    return shaderHandle;
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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  private static int createAndLinkProgram(final int vertexShaderHandle, final int fragmentShaderHandle, final String[] attributes) throws LinkingException
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    {
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    int programHandle = GLES20.glCreateProgram();
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    if (programHandle != 0) 
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      {
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      GLES20.glAttachShader(programHandle, vertexShaderHandle);         
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      GLES20.glAttachShader(programHandle, fragmentShaderHandle);
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      if (attributes != null)
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        {
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        final int size = attributes.length;
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        for (int i = 0; i < size; i++)
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          {
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          GLES20.glBindAttribLocation(programHandle, i, attributes[i]);
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          }                
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        }
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      GLES20.glLinkProgram(programHandle);
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      final int[] linkStatus = new int[1];
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      GLES20.glGetProgramiv(programHandle, GLES20.GL_LINK_STATUS, linkStatus, 0);
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      if (linkStatus[0] != GLES20.GL_TRUE ) 
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        {         
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        String error = GLES20.glGetProgramInfoLog(programHandle);
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        GLES20.glDeleteProgram(programHandle);
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        throw new LinkingException(error);
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        }
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      final int[] numberOfUniforms = new int[1];
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      GLES20.glGetProgramiv(programHandle, GLES20.GL_ACTIVE_UNIFORMS, numberOfUniforms, 0);
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      android.util.Log.d(TAG, "number of active uniforms="+numberOfUniforms[0]);
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      }
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    return programHandle;
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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  private static String generateShaderHeader(final int type)
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    {
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    String header="";
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    switch(type)
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      {
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      case GLES20.GL_VERTEX_SHADER  : header += ("#define NUM_VERTEX "  + getMaxVertex()+"\n");
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                                      for(EffectNames name: EffectNames.values() )
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                                        {
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                                        if( name.getType()==EffectTypes.VERTEX)
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                                        header += ("#define "+name.name()+" "+name.ordinal()+"\n");  
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                                        }
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                                      break;
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      case GLES20.GL_FRAGMENT_SHADER: header += ("#define NUM_FRAGMENT "+ getMaxFragment()+"\n");
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                                      for(EffectNames name: EffectNames.values() )
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                                        {
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                                        if( name.getType()==EffectTypes.FRAGMENT)
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                                        header += ("#define "+name.name()+" "+name.ordinal()+"\n");  
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                                        }
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                                      break;
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     }
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    //Log.d(TAG,""+header);
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    return header;
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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  private static String readTextFileFromRawResource(final Context c, final int resourceId)
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    {
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    final InputStream inputStream = c.getResources().openRawResource(resourceId);
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    final InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
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    final BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
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    String nextLine;
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    final StringBuilder body = new StringBuilder();
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    try
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      {
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      while ((nextLine = bufferedReader.readLine()) != null)
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        {
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        body.append(nextLine);
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        body.append('\n');
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        }
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      }
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    catch (IOException e)
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      {
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      return null;
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      }
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    return body.toString();
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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  private static String getVertexShader(final Context c)
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    {
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    return readTextFileFromRawResource( c, R.raw.main_vertex_shader);
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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  private static String getFragmentShader(final Context c)
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    {
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    return readTextFileFromRawResource( c, R.raw.main_fragment_shader);
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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// Public API
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
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 * Sets Vertical Field of View angle and the point the camera is looking at. This changes the Projection Matrix.
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 *   
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 * @param fov Vertical Field Of View angle, in degrees. If T is the middle of the top edge of the 
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 *            screen, E is the eye point, and B is the middle of the bottom edge of the screen, then 
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 *            fov = angle(TEB)
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 * @param x   X-coordinate of the point the camera is looking at. -scrWidth/2 &lt; x &lt; scrWidth/2
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 * @param y   Y-coordinate of the point the camera is looking at. -scrHeight/2 &lt; y &lt; scrHeight/2
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 */
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  public static void setProjection(float fov, float x, float y)
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    {
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    mFramebuffer.setProjection(fov,x,y);
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
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 * When OpenGL context gets created, you need to call this method so that the library can initialise its internal data structures.
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 * I.e. best called from GLSurfaceView.onSurfaceCreated().
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 * <p>
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 * Compiles the vertex and fragment shaders, establishes the addresses of all uniforms, and initialises all Bitmaps that have already
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 * been created.
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 *   
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 * @param context Context of the App using the library - used to open up Resources and read Shader code.
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 * @throws FragmentCompilationException
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 * @throws VertexCompilationException
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 * @throws VertexUniformsException
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 * @throws FragmentUniformsException
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 * @throws LinkingException
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 */
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  public static void onSurfaceCreated(final Context context) throws FragmentCompilationException,VertexCompilationException,VertexUniformsException,FragmentUniformsException,LinkingException
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    { 
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    mInitialized = true;  
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    final String vertexShader   = Distorted.getVertexShader(context);
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    final String fragmentShader = Distorted.getFragmentShader(context);
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    sanitizeMaxValues();
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    final int vertexShaderHandle   = compileShader(GLES20.GL_VERTEX_SHADER  , vertexShader  );     
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    final int fragmentShaderHandle = compileShader(GLES20.GL_FRAGMENT_SHADER, fragmentShader);     
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    mProgramH = createAndLinkProgram(vertexShaderHandle, fragmentShaderHandle, new String[] {"a_Position",  "a_Color", "a_Normal", "a_TexCoordinate"});                                                            
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    mFramebuffer.setProjection(60.0f,0.0f,0.0f);
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    GLES20.glUseProgram(mProgramH);
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    mTextureUniformH = GLES20.glGetUniformLocation(mProgramH, "u_Texture");
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    mPositionH       = GLES20.glGetAttribLocation( mProgramH, "a_Position");
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    mNormalH         = GLES20.glGetAttribLocation( mProgramH, "a_Normal");
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    mTextureCoordH   = GLES20.glGetAttribLocation( mProgramH, "a_TexCoordinate");
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    GLES20.glEnable (GLES20.GL_DEPTH_TEST);
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    GLES20.glDepthFunc(GLES20.GL_LEQUAL);
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    GLES20.glEnable(GLES20.GL_BLEND);
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    GLES20.glBlendFunc(GLES20.GL_SRC_ALPHA, GLES20.GL_ONE_MINUS_SRC_ALPHA);
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    GLES20.glEnable(GLES20.GL_CULL_FACE);
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    GLES20.glCullFace(GLES20.GL_BACK);
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    GLES20.glFrontFace(GLES20.GL_CW);
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    GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
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    GLES20.glUniform1i(mTextureUniformH, 0);
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    EffectQueueFragment.getUniforms(mProgramH);
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    EffectQueueVertex.getUniforms(mProgramH);
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    EffectQueueMatrix.getUniforms(mProgramH);
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    GLES20.glEnableVertexAttribArray(mPositionH);        
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    GLES20.glEnableVertexAttribArray(mNormalH);
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    GLES20.glEnableVertexAttribArray(mTextureCoordH);
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    DistortedObject.reset();
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    DistortedNode.reset();
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    EffectMessageSender.startSending();
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
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 * Call this when the physical size of the surface we are rendering to changes.
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 * I.e. must be called from GLSurfaceView.onSurfaceChanged()  
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 *   
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 * @param surfaceWidth  new width of the surface.
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 * @param surfaceHeight new height of the surface.
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 */
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  public static void onSurfaceChanged(int surfaceWidth, int surfaceHeight)
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    {
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    mFramebuffer.resize(surfaceWidth,surfaceHeight);
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
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 * Call this so that the Library can release its internal data structures.
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 * Must be called from Activity.onDestroy(). 
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 */
380
  public static void onDestroy()
381
    {
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    DistortedObject.release();
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    DistortedFramebuffer.release();
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    DistortedNode.release();
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    EffectQueue.release();
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    EffectMessageSender.stopSending();
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    mInitialized = false;
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    }
390
  
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
393
 * Returns the true if onSurfaceCreated has been called already, and thus if the Library's is ready
394
 * to accept effect requests.
395
 * 
396
 * @return <code>true</code> if the Library is ready for action, <code>false</code> otherwise.
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 */
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  public static boolean isInitialized()
399
    {
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    return mInitialized;  
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
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 * Returns the maximum number of Matrix effects.
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 *    
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 * @return The maximum number of Matrix effects
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 */
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  public static int getMaxMatrix()
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    {
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    return EffectQueue.getMax(EffectTypes.MATRIX.ordinal());
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
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 * Returns the maximum number of Vertex effects.
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 *    
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 * @return The maximum number of Vertex effects
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 */  
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  public static int getMaxVertex()
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    {
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    return EffectQueue.getMax(EffectTypes.VERTEX.ordinal());
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
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 * Returns the maximum number of Fragment effects.
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 *    
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 * @return The maximum number of Fragment effects
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 */  
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  public static int getMaxFragment()
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    {
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    return EffectQueue.getMax(EffectTypes.FRAGMENT.ordinal());
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
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 * Sets the maximum number of Matrix effects that can be applied to a single DistortedObject at one time.
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 * This can fail if:
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 * <ul>
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 * <li>the value of 'max' is outside permitted range (0 &le; max &le; Byte.MAX_VALUE)
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 * <li>We try to increase the value of 'max' when it is too late to do so already. It needs to be called
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 *     before the Vertex Shader gets compiled, i.e. before the call to {@link #onSurfaceCreated}. After this
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 *     time only decreasing the value of 'max' is permitted.
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 * <li>Furthermore, this needs to be called before any DistortedObject gets created.
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 * </ul>
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 * 
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 * @param max new maximum number of simultaneous Matrix Effects. Has to be a non-negative number not greater
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 *            than Byte.MAX_VALUE 
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 * @return <code>true</code> if operation was successful, <code>false</code> otherwise.
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 */
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  public static boolean setMaxMatrix(int max)
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    {
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    return EffectQueue.setMax(EffectTypes.MATRIX.ordinal(),max);
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
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 * Sets the maximum number of Vertex effects that can be applied to a single DistortedObject at one time.
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 * This can fail if:
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 * <ul>
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 * <li>the value of 'max' is outside permitted range (0 &le; max &le; Byte.MAX_VALUE)
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 * <li>We try to increase the value of 'max' when it is too late to do so already. It needs to be called 
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 *     before the Vertex Shader gets compiled, i.e. before the call to {@link #onSurfaceCreated}. After this
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 *     time only decreasing the value of 'max' is permitted.
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* <li>Furthermore, this needs to be called before any DistortedObject gets created.
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 * </ul>
468
 * 
469
 * @param max new maximum number of simultaneous Vertex Effects. Has to be a non-negative number not greater
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 *            than Byte.MAX_VALUE 
471
 * @return <code>true</code> if operation was successful, <code>false</code> otherwise.
472
 */
473
  public static boolean setMaxVertex(int max)
474
    {
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    return EffectQueue.setMax(EffectTypes.VERTEX.ordinal(),max);
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    }
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///////////////////////////////////////////////////////////////////////////////////////////////////
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/**
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 * Sets the maximum number of Fragment effects that can be applied to a single DistortedObject at one time.
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 * This can fail if:
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 * <ul>
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 * <li>the value of 'max' is outside permitted range (0 &le; max &le; Byte.MAX_VALUE)
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 * <li>We try to increase the value of 'max' when it is too late to do so already. It needs to be called 
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 *     before the Fragment Shader gets compiled, i.e. before the call to {@link #onSurfaceCreated}. After this
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 *     time only decreasing the value of 'max' is permitted.
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 * <li>Furthermore, this needs to be called before any DistortedObject gets created.
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 * </ul>
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 * 
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 * @param max new maximum number of simultaneous Fragment Effects. Has to be a non-negative number not greater
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 *            than Byte.MAX_VALUE 
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 * @return <code>true</code> if operation was successful, <code>false</code> otherwise.
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 */
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  public static boolean setMaxFragment(int max)
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    {
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    return EffectQueue.setMax(EffectTypes.FRAGMENT.ordinal(),max);
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    }
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  }