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.main;

import android.opengl.GLES31;

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

/**

 * Class which represents a OpenGL Framebuffer object.

 * <p>

 * User is able to create offscreen FBOs and both a) render to them b) use their COLOR0 attachment as

 * an input texture. Attaching Depths and/or Stencils is also possible.

 */

public class DistortedFramebuffer extends DistortedOutputSurface implements DistortedInputSurface

  {

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

// Must be called from a thread holding OpenGL Context

  void create()

    {

    if( mColorCreated==NOT_CREATED_YET )

      {

      GLES31.glGenTextures( mNumColors, mColorH, 0);

      GLES31.glGenFramebuffers(1, mFBOH, 0);

      GLES31.glBindFramebuffer(GLES31.GL_FRAMEBUFFER, mFBOH[0]);

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

        {

        GLES31.glBindTexture(GLES31.GL_TEXTURE_2D, mColorH[i]);

        GLES31.glTexParameteri(GLES31.GL_TEXTURE_2D, GLES31.GL_TEXTURE_WRAP_S, GLES31.GL_REPEAT);

        GLES31.glTexParameteri(GLES31.GL_TEXTURE_2D, GLES31.GL_TEXTURE_WRAP_T, GLES31.GL_REPEAT);

        GLES31.glTexParameterf(GLES31.GL_TEXTURE_2D, GLES31.GL_TEXTURE_MIN_FILTER, GLES31.GL_NEAREST);

        GLES31.glTexParameterf(GLES31.GL_TEXTURE_2D, GLES31.GL_TEXTURE_MAG_FILTER, GLES31.GL_LINEAR);

        GLES31.glTexImage2D(GLES31.GL_TEXTURE_2D, 0, GLES31.GL_RGBA, mRealWidth, mRealHeight, 0, GLES31.GL_RGBA, GLES31.GL_UNSIGNED_BYTE, null);

        }

      GLES31.glFramebufferTexture2D(GLES31.GL_FRAMEBUFFER, GLES31.GL_COLOR_ATTACHMENT0, GLES31.GL_TEXTURE_2D, mColorH[0], 0);

      GLES31.glBindTexture(GLES31.GL_TEXTURE_2D, 0);

      GLES31.glBindFramebuffer(GLES31.GL_FRAMEBUFFER, 0);

      mColorCreated = checkStatus("color");

      }

    if( mDepthStencilCreated==NOT_CREATED_YET ) // we need to create a new DEPTH or STENCIL attachment

      {

      GLES31.glGenTextures(1, mDepthStencilH, 0);

      GLES31.glBindTexture(GLES31.GL_TEXTURE_2D, mDepthStencilH[0]);

      GLES31.glTexParameteri(GLES31.GL_TEXTURE_2D, GLES31.GL_TEXTURE_WRAP_S, GLES31.GL_REPEAT);

      GLES31.glTexParameteri(GLES31.GL_TEXTURE_2D, GLES31.GL_TEXTURE_WRAP_T, GLES31.GL_REPEAT);

      GLES31.glTexParameteri(GLES31.GL_TEXTURE_2D, GLES31.GL_TEXTURE_MIN_FILTER, GLES31.GL_NEAREST);

      GLES31.glTexParameteri(GLES31.GL_TEXTURE_2D, GLES31.GL_TEXTURE_MAG_FILTER, GLES31.GL_NEAREST);

      GLES31.glTexParameteri(GLES31.GL_TEXTURE_2D, GLES31.GL_DEPTH_STENCIL_TEXTURE_MODE, GLES31.GL_DEPTH_COMPONENT);

      if( mDepthStencil==DEPTH_NO_STENCIL )

        {

        GLES31.glTexImage2D(GLES31.GL_TEXTURE_2D, 0, GLES31.GL_DEPTH_COMPONENT, mRealWidth, mRealHeight, 0, GLES31.GL_DEPTH_COMPONENT, GLES31.GL_UNSIGNED_INT, null);

        }

      else if( mDepthStencil==BOTH_DEPTH_STENCIL )

        {

        GLES31.glTexImage2D(GLES31.GL_TEXTURE_2D, 0, GLES31.GL_DEPTH24_STENCIL8, mRealWidth, mRealHeight, 0, GLES31.GL_DEPTH_STENCIL, GLES31.GL_UNSIGNED_INT_24_8, null);

        }

      GLES31.glBindTexture(GLES31.GL_TEXTURE_2D, 0);

      GLES31.glBindFramebuffer(GLES31.GL_FRAMEBUFFER, mFBOH[0]);

      if( mDepthStencil==DEPTH_NO_STENCIL )

        {

        GLES31.glFramebufferTexture2D(GLES31.GL_FRAMEBUFFER, GLES31.GL_DEPTH_ATTACHMENT, GLES31.GL_TEXTURE_2D, mDepthStencilH[0], 0);

        }

      else if( mDepthStencil==BOTH_DEPTH_STENCIL )

        {

        GLES31.glFramebufferTexture2D(GLES31.GL_FRAMEBUFFER, GLES31.GL_DEPTH_STENCIL_ATTACHMENT, GLES31.GL_TEXTURE_2D, mDepthStencilH[0], 0);

        }

      GLES31.glBindFramebuffer(GLES31.GL_FRAMEBUFFER, 0);

      mDepthStencilCreated = checkStatus("depth");

      }

    if( mDepthStencilCreated==DONT_CREATE && mDepthStencilH[0]>0 ) // we need to detach and recreate the DEPTH attachment.

      {

      // OpenGL ES 3.0.5 spec, chapter 4.4.2.4 :

      // "Note that the texture image is specifically not detached from any other framebuffer objects.

      //  Detaching the texture image from any other framebuffer objects is the responsibility of the application."

      GLES31.glBindFramebuffer(GLES31.GL_FRAMEBUFFER, mFBOH[0]);

      GLES31.glFramebufferTexture2D(GLES31.GL_FRAMEBUFFER, GLES31.GL_DEPTH_ATTACHMENT        , GLES31.GL_TEXTURE_2D, 0, 0);

      GLES31.glFramebufferTexture2D(GLES31.GL_FRAMEBUFFER, GLES31.GL_DEPTH_STENCIL_ATTACHMENT, GLES31.GL_TEXTURE_2D, 0, 0);

      GLES31.glBindFramebuffer(GLES31.GL_FRAMEBUFFER, 0);

      GLES31.glDeleteTextures(1, mDepthStencilH, 0);

      mDepthStencilH[0]=0;

      }

    }

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

  private int checkStatus(String message)

    {

    int status = GLES31.glCheckFramebufferStatus(GLES31.GL_FRAMEBUFFER);

    if(status != GLES31.GL_FRAMEBUFFER_COMPLETE)

      {

      android.util.Log.e("DistortedFramebuffer", "FRAMEBUFFER INCOMPLETE, "+message+" error="+status);

      GLES31.glDeleteTextures(1, mColorH, 0);

      GLES31.glDeleteTextures(1, mDepthStencilH, 0);

      GLES31.glDeleteFramebuffers(1, mFBOH, 0);

      mFBOH[0]= 0;

      return FAILED_TO_CREATE;

      }

    return CREATED;

    }

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

// Must be called from a thread holding OpenGL Context

  void delete()

    {

    if( mColorH[0]>0 )

      {

      GLES31.glDeleteTextures(1, mColorH, 0);

      mColorH[0] = 0;

      mColorCreated = NOT_CREATED_YET;

      }

    if( mDepthStencilH[0]>0 )

      {

      GLES31.glDeleteTextures(1, mDepthStencilH, 0);

      mDepthStencilH[0]=0;

      mDepthStencilCreated = NOT_CREATED_YET;

      }

    GLES31.glDeleteFramebuffers(1, mFBOH, 0);

    mFBOH[0] = 0;

    }

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

// called from onDestroy(); mark OpenGL assets as 'not created'

  void recreate()

    {

    if( mColorCreated!=DONT_CREATE )

      {

      mColorCreated = NOT_CREATED_YET;

      mColorH[0] = 0;

      }

    if( mDepthStencilCreated!=DONT_CREATE )

      {

      mDepthStencilCreated = NOT_CREATED_YET;

      mDepthStencilH[0] = 0;

      }

    }

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

// create SYSTEM or TREE framebuffers (those are just like normal FBOs, just hold information

// that they were autocreated only for the Library's internal purposes (SYSTEM) or for using

// inside a Tree of DistortedNodes (TREE)

// SYSTEM surfaces do not get removed in onDestroy().

  DistortedFramebuffer(int numcolors, int depthStencil, int type, int width, int height)

    {

    super(width,height,NOT_CREATED_YET,numcolors,depthStencil,NOT_CREATED_YET, type);

    }

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

// PUBLIC API

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

/**

 * Create new offscreen Framebuffer with configurable number of COLOR, DEPTH and STENCIL attachments.

 *

 * @param width        Width of all the COLOR attachments.

 * @param height       Height of all the COLOR attachments.

 * @param numcolors    How many COLOR attachments to create?

 * @param depthStencil Add DEPTH or STENCIL attachment?

 *                     Valid values: NO_DEPTH_NO_STENCIL, DEPTH_NO_STENCIL, BOTH_DEPTH_STENCIL.

 */

  @SuppressWarnings("unused")

  public DistortedFramebuffer(int width, int height, int numcolors, int depthStencil)

    {

    super(width,height,NOT_CREATED_YET,numcolors,depthStencil,NOT_CREATED_YET,TYPE_USER);

    }

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

/**

 * Create new offscreen Framebuffer with COLOR0 attachment only.

 *

 * @param width Width of the COLOR0 attachment.

 * @param height Height of the COLOR0 attachment.

 */

  @SuppressWarnings("unused")

  public DistortedFramebuffer(int width, int height)

    {

    super(width,height,NOT_CREATED_YET, 1, NO_DEPTH_NO_STENCIL,NOT_CREATED_YET,TYPE_USER);

    }

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

/**

 * Bind the underlying rectangle of pixels as a OpenGL Texture.

 *

 * @return <code>true</code> if successful.

 */

  public boolean setAsInput()

    {

    if( mColorH[0]>0 )

      {

      GLES31.glActiveTexture(GLES31.GL_TEXTURE0);

      GLES31.glBindTexture(GLES31.GL_TEXTURE_2D, mColorH[0]);

      return true;

      }

    return false;

    }

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

/**

 * Bind the underlying rectangle of pixels as a OpenGL Texture.

 *

 * @return <code>true</code> if successful.

 */

  public boolean setAsInput(int texture)

    {

    if( texture>=0 && texture<mNumColors && mColorH[texture]>0 )

      {

      GLES31.glActiveTexture(GLES31.GL_TEXTURE0);

      GLES31.glBindTexture(GLES31.GL_TEXTURE_2D, mColorH[texture]);

      return true;

      }

    return false;

    }

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

  public void bindForOutput(int texture)

    {

    if( texture>=0 && texture<mNumColors && mColorH[texture]>0 )

      {

      GLES31.glFramebufferTexture2D(GLES31.GL_FRAMEBUFFER, GLES31.GL_COLOR_ATTACHMENT0, GLES31.GL_TEXTURE_2D, mColorH[texture], 0);

      }

    }

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

/**

 * Enable.disable DEPTH and STENCIL buffers.

 *

 * @param depthStencil Valid values: NO_DEPTH_NO_STENCIL, DEPTH_NO_STENCIL, BOTH_DEPTH_STENCIL.

 */

  public void enableDepthStencil(int depthStencil)

    {

    if( depthStencil != mDepthStencil )

      {

      mDepthStencil = depthStencil;

      if( depthStencil!= NO_DEPTH_NO_STENCIL && mDepthStencilCreated==DONT_CREATE )

        {

        mDepthStencilCreated = NOT_CREATED_YET;

        markForCreation();

        }

      if( depthStencil== NO_DEPTH_NO_STENCIL && mDepthStencilCreated!=DONT_CREATE )

        {

        mDepthStencilCreated = DONT_CREATE;

        markForCreation();

        }

      }

    }

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

/**

 * Return the ID of the Texture (COLOR attachment 0) that's backing this FBO.

 * <p>

 * Catch: this will only work if the library has had time to actually create the texture. Remember

 * that the texture gets created only on first render, thus creating a Texture object and immediately

 * calling this method will return an invalid (negative) result.

 *

 * @return If there was not a single render between creation of the Object and calling this method on

 *         it, return a negative value. Otherwise, return ID of COLOR attachment 0.

 */

  public int getTextureID()

    {

    return mColorH[0];

    }

  }