Distorted Android

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

// Copyright 2016 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.library;

import android.content.res.Resources;

import android.opengl.GLES30;

import org.distorted.library.message.EffectMessage;

import org.distorted.library.program.DistortedProgram;

import org.distorted.library.program.FragmentCompilationException;

import org.distorted.library.program.FragmentUniformsException;

import org.distorted.library.program.LinkingException;

import org.distorted.library.program.VertexCompilationException;

import org.distorted.library.program.VertexUniformsException;

import org.distorted.library.type.Data1D;

import org.distorted.library.type.Dynamic1D;

import org.distorted.library.type.Static1D;

import java.io.InputStream;

import java.nio.ByteBuffer;

import java.nio.ByteOrder;

import java.nio.FloatBuffer;

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

class EffectQueuePostprocess extends EffectQueue

  {

  private static final int POS_DATA_SIZE= 2; // Post Program: size of the position data in elements

  private static final int TEX_DATA_SIZE= 2; // Post Program: size of the texture coordinate data in elements.

  private static final int NUM_UNIFORMS = 4;

  private static final int NUM_CACHE    = 0;

  private static final int INDEX = EffectTypes.POSTPROCESS.ordinal();

  private static final FloatBuffer mQuadPositions, mQuadTextureNor, mQuadTextureInv;

  static

    {

    int dataLength      = 4;

    int bytes_per_float = 4;

    float[] position  = { -0.5f, -0.5f,  -0.5f, 0.5f,  0.5f,-0.5f,  0.5f, 0.5f };

    float[] textureNor= {  0.0f,  0.0f,   0.0f, 1.0f,  1.0f, 0.0f,  1.0f, 1.0f };

    float[] textureInv= {  0.0f,  0.0f,   1.0f, 0.0f,  0.0f, 1.0f,  1.0f, 1.0f };

    mQuadPositions = ByteBuffer.allocateDirect(POS_DATA_SIZE*dataLength*bytes_per_float).order(ByteOrder.nativeOrder()).asFloatBuffer();

    mQuadPositions.put(position).position(0);

    mQuadTextureNor= ByteBuffer.allocateDirect(TEX_DATA_SIZE*dataLength*bytes_per_float).order(ByteOrder.nativeOrder()).asFloatBuffer();

    mQuadTextureNor.put(textureNor).position(0);

    mQuadTextureInv= ByteBuffer.allocateDirect(TEX_DATA_SIZE*dataLength*bytes_per_float).order(ByteOrder.nativeOrder()).asFloatBuffer();

    mQuadTextureInv.put(textureInv).position(0);

    }

  private static DistortedFramebuffer mPostBuffer = new DistortedFramebuffer(true,DistortedSurface.TYPE_SYST,1,1);

                 DistortedFramebuffer mMainBuffer = new DistortedFramebuffer(true,DistortedSurface.TYPE_SYST,1,1);

  // BLUR effect

  private static final float GAUSSIAN[] =   // G(0.00), G(0.03), G(0.06), ..., G(3.00), 0

    {                                       // where G(x)= (1/(sqrt(2*PI))) * e^(-(x^2)/2). The last 0 terminates.

    0.398948f, 0.398769f, 0.398231f, 0.397336f, 0.396086f, 0.394485f, 0.392537f, 0.390247f, 0.387622f, 0.384668f,

    0.381393f, 0.377806f, 0.373916f, 0.369733f, 0.365268f, 0.360532f, 0.355538f, 0.350297f, 0.344823f, 0.339129f,

    0.333229f, 0.327138f, 0.320868f, 0.314436f, 0.307856f, 0.301142f, 0.294309f, 0.287373f, 0.280348f, 0.273248f,

    0.266089f, 0.258884f, 0.251648f, 0.244394f, 0.237135f, 0.229886f, 0.222657f, 0.215461f, 0.208311f, 0.201217f,

    0.194189f, 0.187238f, 0.180374f, 0.173605f, 0.166940f, 0.160386f, 0.153951f, 0.147641f, 0.141462f, 0.135420f,

    0.129520f, 0.123765f, 0.118159f, 0.112706f, 0.107408f, 0.102266f, 0.097284f, 0.092461f, 0.087797f, 0.083294f,

    0.078951f, 0.074767f, 0.070741f, 0.066872f, 0.063158f, 0.059596f, 0.056184f, 0.052920f, 0.049801f, 0.046823f,

    0.043984f, 0.041280f, 0.038707f, 0.036262f, 0.033941f, 0.031740f, 0.029655f, 0.027682f, 0.025817f, 0.024056f,

    0.022395f, 0.020830f, 0.019357f, 0.017971f, 0.016670f, 0.015450f, 0.014305f, 0.013234f, 0.012232f, 0.011295f,

    0.010421f, 0.009606f, 0.008847f, 0.008140f, 0.007483f, 0.006873f, 0.006307f, 0.005782f, 0.005296f, 0.004847f,

    0.004432f, 0.000000f

    };

  private static final int NUM_GAUSSIAN = GAUSSIAN.length-2;

  // Support blurs consisting of the present pixel and up to MAX_BLUR pixels in each direction

  private static final int MAX_BLUR = 50;

  // The (fixed-function-sampled) Gaussian Blur kernels are of the size k0=1, k1=2, k2=2, k3=3, k4=3, k5=4, k6=4,...

  // i.e. k(i)=floor((i+3)/2).  (the 'i' in k(i) means 'blur taking into account the present pixel and 'i' pixels

  // in all 4 directions)

  // We need room for MAX_BLUR of them, and sum(i=0...N, floor((i+3)/2)) = N + floor(N*N/4)

  private static float[] weightsCache = new float[MAX_BLUR + MAX_BLUR*MAX_BLUR/4];

  private static float[] offsetsCache = new float[MAX_BLUR + MAX_BLUR*MAX_BLUR/4];

  private static DistortedProgram mBlurProgram;

  private static int mRadiusH,mOffsetsH,mWeightsH,mDepthH;

  private static float[] mWeights = new float[MAX_BLUR];

  private static float[] mOffsets = new float[MAX_BLUR];

  // another effect ....

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

  EffectQueuePostprocess(long id)

    { 

    super(id,NUM_UNIFORMS,NUM_CACHE,INDEX );

    }

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

  static void createProgram(Resources resources)

  throws FragmentCompilationException,VertexCompilationException,VertexUniformsException,FragmentUniformsException,LinkingException

    {

    final InputStream postVertexStream   = resources.openRawResource(R.raw.blur_vertex_shader);

    final InputStream postFragmentStream = resources.openRawResource(R.raw.blur_fragment_shader);

    mBlurProgram = new DistortedProgram(postVertexStream,postFragmentStream,

                                        "#version 100\n",

                                        "#version 100\n#define MAX_BLUR "+MAX_BLUR);

    int blurProgramH = mBlurProgram.getProgramHandle();

    mRadiusH    = GLES30.glGetUniformLocation( blurProgramH, "u_Radius");

    mOffsetsH   = GLES30.glGetUniformLocation( blurProgramH, "u_Offsets");

    mWeightsH   = GLES30.glGetUniformLocation( blurProgramH, "u_Weights");

    mDepthH     = GLES30.glGetUniformLocation( blurProgramH, "u_Depth");

    }

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

  synchronized boolean compute(long currTime)

    {

    if( currTime==mTime ) return false;

    if( mTime==0 ) mTime = currTime;

    long step = (currTime-mTime);

    for(int i=0; i<mNumEffects; i++)

      {

      mCurrentDuration[i] += step;

      if( mInter[0][i]!=null && mInter[0][i].interpolateMain(mUniforms ,NUM_UNIFORMS*i, mCurrentDuration[i], step) )

        {

        for(int j=0; j<mNumListeners; j++)

          EffectMessageSender.newMessage( mListeners.elementAt(j),

                                          EffectMessage.EFFECT_FINISHED,

                                         (mID[i]<<EffectTypes.LENGTH)+EffectTypes.POSTPROCESS.type,

                                          mName[i],

                                          mObjectID);

        if( EffectNames.isUnity(mName[i], mUniforms, NUM_UNIFORMS*i) )

          {

          remove(i);

          i--;

          continue;

          }

        else mInter[0][i] = null;

        }

      }

    mTime = currTime;

    return true;

    }  

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

  protected void moveEffect(int index)

    {

    mUniforms[NUM_UNIFORMS*index  ] = mUniforms[NUM_UNIFORMS*(index+1)  ];

    mUniforms[NUM_UNIFORMS*index+1] = mUniforms[NUM_UNIFORMS*(index+1)+1];

    mUniforms[NUM_UNIFORMS*index+2] = mUniforms[NUM_UNIFORMS*(index+1)+2];

    mUniforms[NUM_UNIFORMS*index+3] = mUniforms[NUM_UNIFORMS*(index+1)+3];

    }

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

// This implements the 'Better separable implementation using GPU fixed function sampling' from

// https://software.intel.com/en-us/blogs/2014/07/15/an-investigation-of-fast-real-time-gpu-based-image-blur-algorithms

  private void computeGaussianKernel(int radius)

    {

    int offset = radius + radius*radius/4;

    if( weightsCache[offset]==0.0f )

      {

      float z, x= 0.0f, P= (float)NUM_GAUSSIAN / (radius>3 ? radius:3);

      mWeights[0] = GAUSSIAN[0];

      float sum   = GAUSSIAN[0];

      int j;

      for(int i=1; i<=radius; i++)

        {

        x += P;

        j = (int)x;

        z = x-j;

        mWeights[i] = (1-z)*GAUSSIAN[j] + z*GAUSSIAN[j+1];

        sum += 2*mWeights[i];

        }

      for(int i=0; i<=radius; i++) mWeights[i] /= sum;

      int numloops = radius/2;

      weightsCache[offset] = mWeights[0];

      offsetsCache[offset] = 0.0f;

      for(int i=0; i<numloops; i++)

        {

        offsetsCache[offset+i+1] = mWeights[2*i+1]*(2*i+1) + mWeights[2*i+2]*(2*i+2);

        weightsCache[offset+i+1] = mWeights[2*i+1] + mWeights[2*i+2];

        offsetsCache[offset+i+1]/= weightsCache[offset+i+1];

        }

      if( radius%2 == 1 )

        {

        int index = offset + radius/2 +1;

        offsetsCache[index]=mOffsets[radius];

        weightsCache[index]=mWeights[radius];

        }

      }

    }

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

  int postprocess(long time, DistortedOutputSurface surface)

    {

    if( mNumEffects>0 && compute(time) )

      {

      mMainBuffer.setAsInput();

      float w = surface.mWidth;

      float h = surface.mHeight;

      int radius = (int)mUniforms[0];

      if( radius>=MAX_BLUR ) radius = MAX_BLUR-1;

      computeGaussianKernel(radius);

      int offset = radius + radius*radius/4;

      radius = (radius+1)/2;

      for(int i=0; i<=radius; i++) mOffsets[i] = offsetsCache[offset+i]/h;

      mPostBuffer.resizeFast( (int)w, (int)h);

      mPostBuffer.setAsOutput(time);

      GLES30.glViewport(0, 0, (int)w, (int)h);

      mBlurProgram.useProgram();

      GLES30.glUniform1fv( mWeightsH, radius+1, weightsCache,offset);

      GLES30.glUniform1i( mRadiusH, radius);

      GLES30.glUniform1f( mDepthH , 1.0f-surface.mNear);

      // horizontal blur

      GLES30.glUniform1fv( mOffsetsH ,radius+1, mOffsets,0);

      GLES30.glVertexAttribPointer(mBlurProgram.mAttribute[0], POS_DATA_SIZE, GLES30.GL_FLOAT, false, 0, mQuadPositions);

      GLES30.glVertexAttribPointer(mBlurProgram.mAttribute[1], TEX_DATA_SIZE, GLES30.GL_FLOAT, false, 0, mQuadTextureInv);

      GLES30.glDrawArrays(GLES30.GL_TRIANGLE_STRIP, 0, 4);

      // vertical blur

      mPostBuffer.setAsInput();

      surface.setAsOutput(time);

      for(int i=0; i<=radius; i++) mOffsets[i] = offsetsCache[offset+i]/w;

      GLES30.glUniform1fv( mOffsetsH ,radius+1, mOffsets,0);

      GLES30.glDrawArrays(GLES30.GL_TRIANGLE_STRIP, 0, 4);

      }

    return mNumEffects;

    }

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

// blur

  synchronized long add(EffectNames eln, Data1D degree)

    {

    if( mMax[INDEX]>mNumEffects )

      {

      if( degree instanceof Dynamic1D)

        {

        mInter[0][mNumEffects] = (Dynamic1D)degree;

        }

      else if( degree instanceof Static1D)

        {

        mInter[0][mNumEffects] = null;

        mUniforms[NUM_UNIFORMS*mNumEffects] = ((Static1D)degree).getX();

        }

      else return -1;

      mInter[1][mNumEffects] = null;

      mInter[2][mNumEffects] = null;

      return addBase(eln);

      }

    return -1;

    }

  }