/*
   Copyright (C) 2007 guest(r) - guest.r@gmail.com

   This program 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.

   This program 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 this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*/

#pragma parameter AAOFFSET2 "AA offset second pass" 0.5 0.25 2.0 0.05 

#if defined(VERTEX)

#if __VERSION__ >= 130
#define COMPAT_VARYING out
#define COMPAT_ATTRIBUTE in
#define COMPAT_TEXTURE texture
#else
#define COMPAT_VARYING varying 
#define COMPAT_ATTRIBUTE attribute 
#define COMPAT_TEXTURE texture2D
#endif

#ifdef GL_ES
#define COMPAT_PRECISION mediump
#else
#define COMPAT_PRECISION
#endif

COMPAT_ATTRIBUTE vec4 VertexCoord;
COMPAT_ATTRIBUTE vec4 COLOR;
COMPAT_ATTRIBUTE vec4 TexCoord;
COMPAT_VARYING vec4 COL0;
COMPAT_VARYING vec4 TEX0;

vec4 _oPosition1; 
uniform mat4 MVPMatrix;
uniform COMPAT_PRECISION int FrameDirection;
uniform COMPAT_PRECISION int FrameCount;
uniform COMPAT_PRECISION vec2 OutputSize;
uniform COMPAT_PRECISION vec2 TextureSize;
uniform COMPAT_PRECISION vec2 InputSize;

// compatibility #defines
#define vTexCoord TEX0.xy
#define SourceSize vec4(TextureSize, 1.0 / TextureSize) //either TextureSize or InputSize
#define OutSize vec4(OutputSize, 1.0 / OutputSize)

void main()
{
    gl_Position = MVPMatrix * VertexCoord;
    TEX0.xy = TexCoord.xy * 1.00001;
}

#elif defined(FRAGMENT)

#if __VERSION__ >= 130
#define COMPAT_VARYING in
#define COMPAT_TEXTURE texture
out vec4 FragColor;
#else
#define COMPAT_VARYING varying
#define FragColor gl_FragColor
#define COMPAT_TEXTURE texture2D
#endif

#ifdef GL_ES
#ifdef GL_FRAGMENT_PRECISION_HIGH
precision highp float;
#else
precision mediump float;
#endif
#define COMPAT_PRECISION mediump
#else
#define COMPAT_PRECISION
#endif

uniform COMPAT_PRECISION int FrameDirection;
uniform COMPAT_PRECISION int FrameCount;
uniform COMPAT_PRECISION vec2 OutputSize;
uniform COMPAT_PRECISION vec2 TextureSize;
uniform COMPAT_PRECISION vec2 InputSize;
uniform sampler2D Texture;
COMPAT_VARYING vec4 TEX0;

// compatibility #defines
#define Source Texture
#define vTexCoord TEX0.xy
#define texture(c, d) COMPAT_TEXTURE(c, d)
#define SourceSize vec4(TextureSize, 1.0 / TextureSize) //either TextureSize or InputSize
#define OutSize vec4(OutputSize, 1.0 / OutputSize)

#ifdef PARAMETER_UNIFORM
uniform float AAOFFSET2;
#else
#define AAOFFSET2  0.5
#endif 

void main()
{
   vec2 texsize = SourceSize.xy;
   float dx = pow(texsize.x, -1.0) * AAOFFSET2;
   float dy = pow(texsize.y, -1.0) * AAOFFSET2;
   vec3 dt = vec3(1.0, 1.0, 1.0);

   vec2 UL = vTexCoord.xy + vec2(-dx,-dy);
   vec2 UR = vTexCoord.xy + vec2(dx,-dy);
   vec2 DL = vTexCoord.xy + vec2(-dx, dy);
   vec2 DR = vTexCoord.xy + vec2(dx, dy);

   vec3 c00 = texture(Source, UL).xyz;
   vec3 c20 = texture(Source, UR).xyz;
   vec3 c02 = texture(Source, DL).xyz;
   vec3 c22 = texture(Source, DR).xyz;

   float m1=dot(abs(c00-c22),dt)+0.001;
   float m2=dot(abs(c02-c20),dt)+0.001;

   FragColor = vec4((m1*(c02+c20)+m2*(c22+c00))/(2.0*(m1+m2)),1.0);
} 
#endif
