// CRT-torridgristle - Candy Bloom
// license: public domain

#pragma parameter GlowLevel "Glow Level" 1.0 0.0 1.0 0.1
#pragma parameter GlowTightness "Glow Tightness" 0.5 0.0 1.0 0.1

#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;
}

#elif defined(FRAGMENT)

#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

#if __VERSION__ >= 130
#define COMPAT_VARYING in
#define COMPAT_TEXTURE texture
out COMPAT_PRECISION vec4 FragColor;
#else
#define COMPAT_VARYING varying
#define FragColor gl_FragColor
#define COMPAT_TEXTURE texture2D
#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;
uniform sampler2D PassPrev3Texture;
COMPAT_VARYING vec4 TEX0;

#define candy_ref PassPrev3Texture

// compatibility #defines
#define Source Texture
#define vTexCoord TEX0.xy

#define SourceSize vec4(TextureSize, 1.0 / TextureSize) //either TextureSize or InputSize
#define OutSize vec4(OutputSize, 1.0 / OutputSize)

#ifdef PARAMETER_UNIFORM
uniform COMPAT_PRECISION float GlowLevel, GlowTightness;
#else
#define GlowLevel 1.0
#define GlowTightness 0.5
#endif

void main()
{
	vec3 Picture = COMPAT_TEXTURE(Source, vTexCoord).xyz;

    float MaxRGB       = max(Picture.x, max(Picture.y, Picture.z));
    float MinRGB       = min(Picture.x, min(Picture.y, Picture.z));

    float YIQLuminance = ((0.299*Picture.x) + (0.587*Picture.y) + (0.114*Picture.z));
    
    
    Picture /= MaxRGB;
    Picture = clamp(Picture,0.0,1.0);
    
    
    FragColor = vec4(mix(COMPAT_TEXTURE(candy_ref, vTexCoord).xyz, Picture, mix(1.-pow(1.-YIQLuminance,2.0),YIQLuminance*YIQLuminance,GlowTightness)*GlowLevel),1.0);
} 
#endif
