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;

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

 * Class which represents a OpenGL Framebuffer object.

 * of the library (the first constructor; primary use case: the screen) or an offscreen

 * because we can only delete from a thread that holds the OpenGL context so here we provide a

  private int[] mFBOH   = new int[1];

  private float mX, mY, mFOV;

  float mDistance;

      GLES30.glBindTexture(GLES30.GL_TEXTURE_2D, mColorH[0]);

      GLES30.glTexParameteri(GLES30.GL_TEXTURE_2D, GLES30.GL_TEXTURE_WRAP_T, GLES30.GL_REPEAT);

      GLES30.glTexParameterf(GLES30.GL_TEXTURE_2D, GLES30.GL_TEXTURE_MIN_FILTER, GLES30.GL_NEAREST);

      GLES30.glTexParameterf(GLES30.GL_TEXTURE_2D, GLES30.GL_TEXTURE_MAG_FILTER, GLES30.GL_LINEAR);

      GLES30.glBindFramebuffer(GLES30.GL_FRAMEBUFFER, mFBOH[0]);

      GLES30.glFramebufferTexture2D(GLES30.GL_FRAMEBUFFER, GLES30.GL_COLOR_ATTACHMENT0, GLES30.GL_TEXTURE_2D, mColorH[0], 0);

      GLES30.glBindTexture(GLES30.GL_TEXTURE_2D, mDepthH[0]);

      GLES30.glTexParameteri(GLES30.GL_TEXTURE_2D, GLES30.GL_TEXTURE_WRAP_T, GLES30.GL_REPEAT);

      GLES30.glTexParameteri(GLES30.GL_TEXTURE_2D, GLES30.GL_TEXTURE_MIN_FILTER, GLES30.GL_NEAREST);

      GLES30.glTexParameteri(GLES30.GL_TEXTURE_2D, GLES30.GL_TEXTURE_MAG_FILTER, GLES30.GL_NEAREST);

      GLES30.glFramebufferTexture2D(GLES30.GL_FRAMEBUFFER, GLES30.GL_DEPTH_ATTACHMENT, GLES30.GL_TEXTURE_2D, mDepthH[0], 0);

      mDepthH[0]=NOT_CREATED_YET;

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

  private boolean checkStatus(String message)

    {

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

      GLES30.glDeleteTextures(1, mDepthH, 0);

      GLES30.glDeleteFramebuffers(1, mFBOH, 0);

      mFBOH[0]   = 0;

      mColorH[0] = FAILED_TO_CREATE;

      mDepthH[0] = FAILED_TO_CREATE;

      return false;

      }

    }

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

        mDepthH[0]=NOT_CREATED_YET;

      mColorH[0] = NOT_CREATED_YET;

      mFBOH[0] = 0;

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

  void destroy()

    {

    if( mColorH[0]!=DONT_CREATE ) mColorH[0] = NOT_CREATED_YET;

    if( mDepthEnabled           ) mDepthH[0] = NOT_CREATED_YET;

    }

  void setAsOutput()

    {

      GLES30.glDepthMask(true);

    else

      {

      GLES30.glDepthMask(false);

  private void createProjection()

    {

    if( mWidth>0 && mHeight>1 )

      {

      if( mFOV>0.0f )  // perspective projection

        {

        float left   = (-mX-mWidth /2.0f)/mHeight;

        float right  = (-mX+mWidth /2.0f)/mHeight;

        float bottom = (-mY-mHeight/2.0f)/mHeight;

        float top    = (-mY+mHeight/2.0f)/mHeight;

        float near   = (top-bottom) / (2.0f*(float)Math.tan(mFOV*Math.PI/360));

        mDistance    = mHeight*near/(top-bottom);

        float far    = 2*mDistance-near;

        mDepth       = (int)((far-near)/2);

        Matrix.frustumM(mProjectionMatrix, 0, left, right, bottom, top, near, far);

        }

      else             // parallel projection

        {

        float left   = -mX-mWidth /2.0f;

        float right  = -mX+mWidth /2.0f;

        float bottom = -mY-mHeight/2.0f;

        float top    = -mY+mHeight/2.0f;

        float near   = (mWidth+mHeight)/2;

        mDistance    = 2*near;

        float far    = 3*near;

        mDepth       = (int)near;

        Matrix.orthoM(mProjectionMatrix, 0, left, right, bottom, top, near, far);

        }

      }

    }

// if new size fits into the size of the underlying Texture, just change the projection without

// reallocating the Texture. Otherwise, we need to reallocate.

//

// Must be called form a thread holding the OpenGL context.

  void resizeFast(int width, int height)

    {

    if( mWidth!=width || mHeight!=height )

      {

      mWidth = width;

      mHeight= height;

      createProjection();

        mSizeY = mHeight;

        delete();

      }

// PUBLIC API

 * Create a new offscreen Framebuffer.

 *

 * @param width Width of the COLOR attachment.

 * @param height Height of the COLOR attachment.

 * @param depthEnabled Add DEPTH attachment?

 */

  @SuppressWarnings("unused")

  public DistortedFramebuffer(int width, int height, boolean depthEnabled)

    {

    mHeight      = height;

    mWidth       = width;

    mFOV         = 60.0f;

    mX           = 0.0f;

    mY           = 0.0f;

    mDepthEnabled= depthEnabled;

    mDepthH[0]   = NOT_CREATED_YET;

    createProjection();

    }

 * @param width Width of the COLOR attachment.

 * @param height Height of the COLOR attachment.

 */

    mWidth       = width;

    mFOV         = 60.0f;

    mX           = 0.0f;

    mY           = 0.0f;

    mDepthEnabled= false;

    mDepthH[0]   = NOT_CREATED_YET;

    }

 * <p>

 * Has to be followed by a 'resize()' to set the size.

 * @param fbo the ID of a OpenGL Framebuffer object. Typically 0 (the screen)

 */

    mX           = 0.0f;

    mY           = 0.0f;

    mDepthEnabled= true;

    mDepthH[0]   = DONT_CREATE;

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

/**

 * Create a new DEPTH buffer and attach it or (param=false) detach an existing DEPTh attachment and destroy it.

 *

 *               <bold>false</bold> if we want to detach the DEPTH attachment.

 * @param time Current time, in milliseconds.

 */

    create();      // the 'setAsInput' because this has side-effects!

    }

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

 * Draws the Tree, and all its children, to the Framebuffer.

 * <p>

 * @param dt DistortedTree to render.

 * @param time Current time, in milliseconds. This will be passed to all the Effects stored in the Tree.

 */

  public void renderTo(DistortedTree dt, long time)

    {

    }

 * Create new Projection matrix.

 *

 * @param fov Vertical 'field of view' of the Projection frustrum (in degrees).

 * @param y Y-coordinate of the point at which our camera looks at. 0 is the center.

  public void setProjection(float fov, float x, float y)

    mY   = y;

    createProjection();

    }

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

 * Resize the underlying Framebuffer.

 *

 * As the Framebuffer is not created until the first render, typical usage of this API is actually

 * to set the size of an not-yet-created Framebuffer of an object that has been created with the

 * second constructor.

 * resize takes place on the next render.

 * @param width The new width.

 * @param height The new height.

 */

    {

      {

      mHeight= height;

      mSizeY = height;

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

/**

 * <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.

 *

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

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

/**

 * Return true if the FBO contains a DEPTH attachment.

 *

 * @return <bold>true</bold> if the FBO contains a DEPTH attachment.

 */

  public boolean hasDepth()

    {