Distorted Android

  VERTEX_SHEAR     ( EffectType.VERTEX  ,   new float[] {0.0f,0.0f,0.0f} , 3, 0,     3    , VertexEffectShear.class        ),

             + "vec3 center = vUniforms[effect+1].yzw;        \n"

             + "v -= center;                                  \n"

             + "v += center;                                  \n"

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

// Copyright 2020 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.effect;

import org.distorted.library.type.Data3D;

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

/**

 * Shear the Mesh.

 */

public class VertexEffectShear extends VertexEffect

  {

  private Data3D mShear, mCenter;

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

/**

 * Only for use by the library itself.

 *

 * @y.exclude

 */

  public boolean compute(float[] uniforms, int index, long currentDuration, long step )

    {

    mCenter.get(uniforms,index+CENTER_OFFSET,currentDuration,step);

    return mShear.get(uniforms,index,currentDuration,step);

    }

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

// PUBLIC API

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

/*

  float sx = uniforms[NUM_UNIFORMS*index  ];

    float sy = uniforms[NUM_UNIFORMS*index+1];

    float sz = uniforms[NUM_UNIFORMS*index+2];

    float x  = uniforms[NUM_UNIFORMS*index+CENTER_OFFSET  ];

    float y  = uniforms[NUM_UNIFORMS*index+CENTER_OFFSET+1];

    float z  = uniforms[NUM_UNIFORMS*index+CENTER_OFFSET+2];

    Matrix.translateM(matrix, 0, x, y, z);

    matrix[4] += sx*matrix[0]; // Multiply viewMatrix by 1 x 0 0 , i.e. X-shear.

    matrix[5] += sx*matrix[1]; //                        0 1 0 0

    matrix[6] += sx*matrix[2]; //                        0 0 1 0

    matrix[7] += sx*matrix[3]; //                        0 0 0 1

    matrix[0] += sy*matrix[4]; // Multiply viewMatrix by 1 0 0 0 , i.e. Y-shear.

    matrix[1] += sy*matrix[5]; //                        y 1 0 0

    matrix[2] += sy*matrix[6]; //                        0 0 1 0

    matrix[3] += sy*matrix[7]; //                        0 0 0 1

    matrix[4] += sz*matrix[8]; // Multiply viewMatrix by 1 0 0 0 , i.e. Z-shear.

    matrix[5] += sz*matrix[9]; //                        0 1 0 0

    matrix[6] += sz*matrix[10];//                        0 z 1 0

    matrix[7] += sz*matrix[11];//                        0 0 0 1

    Matrix.translateM(matrix, 0,-x,-y,-z);

*/

/**

 * Have to call this before the shaders get compiled (i.e before DistortedLibrary.onCreate()) for the Effect to work.

 */

  public static void enable()

    {

    addEffect( EffectName.VERTEX_SHEAR,

               "float sx = vUniforms[effect].x;               \n"

             + "float sy = vUniforms[effect].y;               \n"

             + "float sz = vUniforms[effect].z;               \n"

             + "vec3 center = vUniforms[effect+1].yzw;        \n"

             + "v -= center;                                  \n"

             + "float new_vx = (1.0+sx*sy)*v.x + sx*v.y;      \n"

             + "float new_vy = sy*v.x + v.y;                  \n"

             + "float new_vz = sz*v.y + v.z;                  \n"

             + "v.x = new_vx;                                 \n"

             + "v.y = new_vy;                                 \n"

             + "v.z = new_vz;                                 \n"

             + "v += center;                                  \n"

             + "float new_nx = (1.0+sx*sy)*n.x + sx*n.y;      \n"

             + "float new_ny = sy*n.x + n.y;                  \n"

             + "float new_nz = sz*n.y + n.z;                  \n"

             + "n.x = new_nx;                                 \n"

             + "n.y = new_ny;                                 \n"

             + "n.z = new_nz;                                 \n"

             );

    }

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

/**

 * Shear the Mesh.

 *

 * @param shear   The 3-tuple of shear factors. The first controls level

 *                of shearing in the X-axis, second - Y-axis and the third -

 *                Z-axis. Each is the tangent of the shear angle, i.e 0 -

 *                no shear, 1 - shear by 45 degrees (tan(45deg)=1) etc.

 * @param center  Center of shearing, i.e. the point which stays unmoved.

 */

  public VertexEffectShear(Data3D shear, Data3D center)

    {

    super(EffectName.VERTEX_SHEAR);

    mShear = shear;

    mCenter = center;

    }

  }