Distorted Android

// 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                     //

// Distorted is distributed in the hope that it will be useful,                             //

// but WITHOUT ANY WARRANTY; without even the implied warranty of                           //

// along with Distorted.  If not, see <http://www.gnu.org/licenses/>.                       //

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

precision highp float;

precision highp int;

in vec3 a_Position;                  // Per-vertex position.

in vec3 a_Inflate;                   // This vector describes the direction this vertex needs to go when we 'inflate' the whole mesh.

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

in float a_Tag;                      // Per-vertex tag. Connects the vertex (really the mesh component the vertex is a member of) to a vertex effect.

out vec3 v_Position;                 //

out vec3 v_endPosition;              // for Transform Feedback only

out vec3 v_Normal;                   //

uniform mat4 u_MVPMatrix;            // the combined model/view/projection matrix.

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

uniform int vNumEffects;             // total number of vertex effects

uniform int vName[NUM_VERTEX];       // their names.

uniform vec4 vUniforms[3*NUM_VERTEX];// i-th effect is 3 consecutive vec4's: [3*i], [3*i+1], [3*i+2].

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

uniform int vTag[NUM_VERTEX];        // Tags of the vertex effects. Tags are used to connect an effect to a Mesh component.

// Return degree of the point as defined by the Region. Currently only supports spherical regions.

//

// Let region.xyz be the vector from point S to point O (the center point of the region sphere)

//

// Then, the degree of a point with respect to a given (spherical!) Region is defined by:

//

// If P is outside the sphere, return 0.

// Otherwise, let X be the point where the halfline SP meets the sphere - then return |PX|/|SX|,

// aka the 'degree' of point P.

// We solve the triangle OPX.

// We know the lengths |PO|, |OX| and the angle OPX, because cos(OPX) = cos(180-OPS) = -cos(OPS) = -PS*PO/(|PS|*|PO|)

float degree(in vec4 region, in vec3 PS)

  {

  vec3 PO  = PS + region.xyz;

  float ps_sq = dot(PS,PS);

  float one_over_ps_sq = 1.0/(ps_sq-(sign(ps_sq)-1.0));  // return 1.0 if ps_sq = 0.0

  float DOT  = dot(PS,PO)*one_over_ps_sq;

  return 1.0 / (1.0 + 1.0/(sqrt(DOT*DOT+D*one_over_ps_sq)-DOT));

  }

#endif  // NUM_VERTEX>0

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

  vec3 v = a_Position + u_Inflate*a_Inflate;

  vec3 n = a_Normal;

#ifdef PREAPPLY

#if NUM_VERTEX>0

  int effect=0;

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

    // ENABLED EFFECTS WILL BE INSERTED HERE

    effect+=3;

    }

  v_Position      = v;

  v_Inflate       = inf;

#else

  v_TexCoordinate = a_TexCoordinate;

  v_Normal        = normalize(vec3(u_MVMatrix*vec4(n,0.0)));

  gl_Position     = u_MVPMatrix*vec4(v,1.0);

  }