/*
	Scanlines Sine Absolute Value
	An ultra light scanline shader
	RiskyJumps
*/
#pragma parameter amp          "Amplitude"      1.2500  0.000 2.000 0.05
#pragma parameter phase        "Phase"          0.5000  0.000 2.000 0.05
#pragma parameter lines_black  "Lines Blacks"   0.0000  0.000 1.000 0.05
#pragma parameter lines_white  "Lines Whites"   1.0000  0.000 2.000 0.05

#define freq             0.500000
#define offset           0.000000
#define pi               3.141592654

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

#ifdef PARAMETER_UNIFORM
uniform COMPAT_PRECISION float amp;
uniform COMPAT_PRECISION float phase;
uniform COMPAT_PRECISION float lines_black;
uniform COMPAT_PRECISION float lines_white;
#else
#define amp              1.250000
#define phase            0.500000
#define lines_black      0.000000
#define lines_white      1.000000
#endif



#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

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

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

void main()
{
	gl_Position = MVPMatrix * VertexCoord;
	COL0 = COLOR;
	TEX0.xy = TexCoord.xy;

	float omega = 2.0 * pi * freq;				// Angular frequency
	angle = TEX0.y * omega * TextureSize.y + phase;
}

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

// 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 OutputSize vec4(OutputSize, 1.0 / OutputSize)

#ifdef PARAMETER_UNIFORM
// All parameter floats need to have COMPAT_PRECISION in front of them
uniform COMPAT_PRECISION float SCANLINE_BASE_BRIGHTNESS;
uniform COMPAT_PRECISION float SCANLINE_SINE_COMP_A;
uniform COMPAT_PRECISION float SCANLINE_SINE_COMP_B;
#else
#define SCANLINE_BASE_BRIGHTNESS 0.95
#define SCANLINE_SINE_COMP_A 0.0
#define SCANLINE_SINE_COMP_B 0.15
#endif

void main()
{
	vec3 color = texture(Source, vTexCoord).xyz;
	float grid;

	float lines;

	lines = sin(angle);
	lines *= amp;
	lines += offset;
	lines = abs(lines);
	lines *= lines_white - lines_black;
	lines += lines_black;
	color *= lines;

	FragColor = vec4(color.xyz, 1.0);
}
#endif