#version 450




layout(push_constant)uniform Push
{
 vec4 OutputSize;
 vec4 OriginalSize;
 vec4 SourceSize;
 uint FrameCount;
 float aspect_x;
 float aspect_y;
 float border_zoom;
 float BRIGHTNESS;
 float integer_scale;
 float overscale;
 float scanline_toggle;
 float interp_toggle;
 float THICKNESS;
 float DARKNESS;
 float OS_MASK_TOP;
 float OS_MASK_BOTTOM;
 float OS_MASK_LEFT;
 float OS_MASK_RIGHT;
} params;

#pragma parameteraspect_x¡64.01.0256.1.0
#pragma parameteraspect_y¡49.01.0256.1.0
#pragma parameterborder_zoom¡1.50.5100.5
#pragma parameterBRIGHTNESS¡0.0-1.01.00.05
#pragma parameterinteger_scale¡1.00.01.01.0
#pragma parameteroverscale¡0.00.01.01.0
#pragma parameterscanline_toggle¡0.00.01.01.0
#pragma parameterinterp_toggle¡0.00.01.01.0
#pragma parameterTHICKNESS¡2.01.012.01.0
#pragma parameterDARKNESS¡0.350.01.00.05
#pragma parameterOS_MASK_TOP¡0.00.01.00.005
#pragma parameterOS_MASK_BOTTOM¡0.00.01.00.005
#pragma parameterOS_MASK_LEFT¡0.00.01.00.005
#pragma parameterOS_MASK_RIGHT¡0.00.01.00.005

layout(std140, set = 0, binding = 0)uniform UBO
{
   mat4 MVP;
} global;

#pragma stagevertex
layout(location = 0)in vec4 Position;
layout(location = 1)in vec2 TexCoord;
layout(location = 0)out vec2 vTexCoord;
layout(location = 1)out vec2 tex_border;

void main()
{
 gl_Position = global . MVP * Position;
 vec2 out_res = params . OutputSize . xy;
 vec2 corrected_size = params . SourceSize . xy * vec2(params . aspect_x / params . aspect_y, 1.0)
   * vec2(params . SourceSize . y / params . SourceSize . x, 1.0);
 float full_scale =(params . integer_scale > 0.5)? floor(params . OutputSize . y /
  params . SourceSize . y)+ params . overscale : params . OutputSize . y / params . SourceSize . y;
 vec2 scale =(params . OutputSize . xy / corrected_size)/ full_scale;
 vec2 middle = vec2(0.49999, 0.49999);
 vec2 diff = TexCoord . xy - middle;
 vTexCoord = middle + diff * scale;
 vec2 zoom_coord =(((TexCoord . xy - middle)/ params . border_zoom)* vec2(params . OutputSize . x / params . OutputSize . y, 1.0)
  / vec2(params . aspect_x / params . aspect_y, 1.0))+ middle;
 tex_border = zoom_coord;
}

#pragma stagefragment
layout(location = 0)in vec2 vTexCoord;
layout(location = 1)in vec2 tex_border;
layout(location = 0)out vec4 FragColor;
layout(set = 0, binding = 2)uniform sampler2D Source;
layout(set = 0, binding = 3)uniform sampler2D Reference;

vec4 scanlines(vec4 frame, vec2 coord, vec2 texture_size, vec2
 video_size, vec2 output_size)
{
 float lines = fract(coord . y * texture_size . y);
 float scale_factor = floor((output_size . y / video_size . y)+ 0.4999);
    float lightness = 1.0 - params . DARKNESS;
 return(params . scanline_toggle > 0.5 &&(lines <(1.0 / scale_factor * params . THICKNESS)))
  ? frame * vec4(lightness, lightness, lightness, lightness): frame;
}

vec2 interp_coord(vec2 coord, vec2 texture_size)
{
 vec2 p = coord . xy;
 p = p * texture_size . xy + vec2(0.5, 0.5);
 vec2 i = floor(p);
 vec2 f = p - i;

 f = f * f * f * f *(f *(f *(- 20.0 * f + vec2(70.0, 70.0))- vec2(84.0, 84.0))+ vec2(35.0, 35.0));
 p = i + f;
 p =(p - vec2(0.5, 0.5))* 1.0 / texture_size;
 return p;
}

vec4 border(vec2 texture_size, vec2 video_size, vec2 output_size,
 float frame_count, vec2 tex, sampler2D decal, vec2 tex_border, sampler2D ORIG)
{
 vec4 effect = texture(decal, tex_border);
 effect += vec4(vec3(params . BRIGHTNESS), effect . w);

 vec2 coord =(params . interp_toggle < 0.5)? tex : interp_coord(tex, texture_size);
 vec4 frame = texture(ORIG, coord);
 frame = scanlines(frame, tex, texture_size, video_size, output_size);
 vec2 fragcoord =(coord . xy);
 if(fragcoord . x < 1.0 - params . OS_MASK_RIGHT && fragcoord . x > 0.0 + params . OS_MASK_LEFT &&
  fragcoord . y < 1.0 - params . OS_MASK_BOTTOM && fragcoord . y > 0.0 + params . OS_MASK_TOP)
   return frame;

 else return effect;
}

void main()
{
 FragColor = border(params . SourceSize . xy, params . SourceSize . xy, params . OutputSize . xy,
  float(params . FrameCount), vTexCoord, Source, tex_border, Reference);
}