Distorted Android

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// Copyright 2016 Leszek Koltunski                                                          //

//                                                                                          //

// the Free Software Foundation, either version 2 of the License, or                        //

// (at your option) any later version.                                                      //

//                                                                                          //

// 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                        // 

in vec3 a_Normal;                     // Per-vertex normal vector.

in vec2 a_TexCoordinate;              // Per-vertex texture coordinate.

in float a_Component;                 // The component a vertex belongs to.

                                      // to a vertex effect. An effect will only be active on a vertex iff (a_Association & vAssociation[effect]) != 0.

                                      // ( see VertexEffect.retSection() )

out vec3 v_Normal;                    //

out vec2 v_TexCoordinate;             //

uniform mat4 u_MVMatrixP;             // the combined model/view matrix. (for points)

uniform mat4 u_MVMatrixV;             // the combined model/view matrix. (for vectors)

                                      // which need to work differently on points and vectors

uniform float u_Inflate;              // how much should we inflate (>0.0) or deflate (<0.0) the mesh.

uniform int u_TransformFeedback;      // are we doing the transform feedback now?

uniform ivec4 vProperties[NUM_VERTEX];// their properties, 4 ints:

                                      // 1: name of the effect

                                      // 2: effect's AND association

                                      // 3: reserved int (probably another AND assoc in the future)

                                      // 4: effect's EQU association

                                      // The first vec4 is the Interpolated values,

                                      // second vec4: first float - cache, next 3: Center, the third -  the Region.

                                      // 1: component's AND association

                                      // 2: reserved. Probably another AND assoc in the future.

                                      // 3: component's EQU association

                                      // 4: reserved

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// HELPER FUNCTIONS

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// Let 'PS' be the vector from point P (the current vertex) to point S (the center of the effect).

// Let region.w be the radius of the region sphere.

// (This all should work regardless if S is inside or outside of the sphere).

//

// then from the law of cosines PX^2 + PO^2 - 2*PX*PO*cos(OPX) = OX^2 so PX = -a + sqrt(a^2 + OX^2 - PO^2)

// where a = PS*PO/|PS| but we are really looking for d = |PX|/(|PX|+|PS|) = 1/(1+ (|PS|/|PX|) ) and

// |PX|/|PS| = -b + sqrt(b^2 + (OX^2-PO^2)/PS^2) where b=PS*PO/|PS|^2 which can be computed with only one sqrt.

  float d = region.w*region.w-dot(PO,PO);

  if( d<=0.0 ) return 0.0;

  float b = dot(PS,PO)/ps_sq;

  return 1.0 / (1.0 + 1.0/(sqrt(b*b + d/ps_sq)-b));

void main()

  {

  vec3 v = a_Position + u_Inflate*(a_Position - vComCenter[component].xyz);

#if NUM_VERTEX>0

    {

      // ENABLED EFFECTS WILL BE INSERTED HERE

#endif

#ifdef PREAPPLY

  v_endPosition= n;

    {

    vec4 tmp1 =  u_MVMatrixP * vec4(v,1.0);

    vec4 tmp2 =  normalize(u_MVMatrixV * vec4(n,0.0));

    v_Position    = vec3(tmp1);

    v_endPosition = vec3(tmp1+100.0*tmp2);

    }

    {

    v_Position = v;

    }