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/crt-geom-flat.cg

Created Jun 20, 2016
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#pragma parameter CRTgamma "CRTGeom Target Gamma" 2.4 0.1 5.0 0.1
#pragma parameter monitorgamma "CRTGeom Monitor Gamma" 2.2 0.1 5.0 0.1
#pragma parameter d "CRTGeom Distance" 1.5 0.1 3.0 0.1
#pragma parameter CURVATURE "CRTGeom Curvature Toggle" 0.0 0.0 1.0 1.0
#pragma parameter R "CRTGeom Curvature Radius" 2.0 0.1 10.0 0.1
#pragma parameter cornersize "CRTGeom Corner Size" 0.001 0.001 1.0 0.005
#pragma parameter cornersmooth "CRTGeom Corner Smoothness" 1000.0 80.0 2000.0 100.0
#pragma parameter x_tilt "CRTGeom Horizontal Tilt" 0.0 -0.5 0.5 0.05
#pragma parameter y_tilt "CRTGeom Vertical Tilt" 0.0 -0.5 0.5 0.05
#pragma parameter overscan_x "CRTGeom Horiz. Overscan %" 100.0 -125.0 125.0 1.0
#pragma parameter overscan_y "CRTGeom Vert. Overscan %" 100.0 -125.0 125.0 1.0
#pragma parameter DOTMASK "CRTGeom Dot Mask Toggle" 0.3 0.0 0.3 0.3
#pragma parameter SHARPER "CRTGeom Sharpness" 1.0 1.0 3.0 1.0
#pragma parameter scanline_weight "CRTGeom Scanline Weight" 0.3 0.1 0.5 0.05
#ifdef PARAMETER_UNIFORM
uniform float CRTgamma;
uniform float monitorgamma;
uniform float d;
uniform float CURVATURE;
uniform float R;
uniform float cornersize;
uniform float cornersmooth;
uniform float x_tilt;
uniform float y_tilt;
uniform float overscan_x;
uniform float overscan_y;
uniform float DOTMASK;
uniform float SHARPER;
uniform float scanline_weight;
#else
#define CRTgamma 2.4
#define monitorgamma 2.2
#define d 1.5
#define CURVATURE 0.0
#define R 2.0
#define cornersize 0.001
#define cornersmooth 8000.0
#define x_tilt 0.0
#define y_tilt 0.0
#define overscan_x 100.0
#define overscan_y 100.0
#define DOTMASK 0.3
#define SHARPER 1.0
#define scanline_weight 0.3
#endif
// END PARAMETERS //
/* COMPATIBILITY
- HLSL compilers
- Cg compilers
*/
/*
CRT-interlaced
Copyright (C) 2010-2012 cgwg, Themaister and DOLLS
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.
(cgwg gave their consent to have the original version of this shader
distributed under the GPL in this message:
http://board.byuu.org/viewtopic.php?p=26075#p26075
"Feel free to distribute my shaders under the GPL. After all, the
barrel distortion code was taken from the Curvature shader, which is
under the GPL."
)
This shader variant is pre-configured with screen curvature
*/
// Comment the next line to disable interpolation in linear gamma (and
// gain speed).
#define LINEAR_PROCESSING
// Enable 3x oversampling of the beam profile; improves moire effect caused by scanlines+curvature
#define OVERSAMPLE
// Use the older, purely gaussian beam profile; uncomment for speed
//#define USEGAUSSIAN
// Use interlacing detection; may interfere with other shaders if combined
#define INTERLACED
// Enable Dot-mask emulation:
// Output pixels are alternately tinted green and magenta.
// #define DOTMASK
// Macros.
#define FIX(c) max(abs(c), 1e-5);
#define PI 3.141592653589
#ifdef LINEAR_PROCESSING
# define TEX2D(c) pow(tex2D(s0, (c)), float4(CRTgamma))
#else
# define TEX2D(c) tex2D(s0, (c))
#endif
// aspect ratio
static float2 aspect = float2(1.0, 0.75);
float intersect(float2 xy, float2 sinangle, float2 cosangle)
{
float A = dot(xy,xy)+d*d;
float B = 2.0*(R*(dot(xy,sinangle)-d*cosangle.x*cosangle.y)-d*d);
float C = d*d + 2.0*R*d*cosangle.x*cosangle.y;
return (-B-sqrt(B*B-4.0*A*C))/(2.0*A);
}
float2 bkwtrans(float2 xy, float2 sinangle, float2 cosangle)
{
float c = intersect(xy, sinangle, cosangle);
float2 point = float2(c)*xy;
point -= float2(-R)*sinangle;
point /= float2(R);
float2 tang = sinangle/cosangle;
float2 poc = point/cosangle;
float A = dot(tang,tang)+1.0;
float B = -2.0*dot(poc,tang);
float C = dot(poc,poc)-1.0;
float a = (-B+sqrt(B*B-4.0*A*C))/(2.0*A);
float2 uv = (point-a*sinangle)/cosangle;
float r = FIX(R*acos(a));
return uv*r/sin(r/R);
}
float2 fwtrans(float2 uv, float2 sinangle, float2 cosangle)
{
float r = FIX(sqrt(dot(uv,uv)));
uv *= sin(r/R)/r;
float x = 1.0-cos(r/R);
float D = d/R + x*cosangle.x*cosangle.y+dot(uv,sinangle);
return d*(uv*cosangle-x*sinangle)/D;
}
float3 maxscale(float2 sinangle, float2 cosangle)
{
float2 c = bkwtrans(-R * sinangle / (1.0 + R/d*cosangle.x*cosangle.y), sinangle, cosangle);
float2 a = float2(0.5,0.5)*aspect;
float2 lo = float2(fwtrans(float2(-a.x,c.y), sinangle, cosangle).x,
fwtrans(float2(c.x,-a.y), sinangle, cosangle).y)/aspect;
float2 hi = float2(fwtrans(float2(+a.x,c.y), sinangle, cosangle).x,
fwtrans(float2(c.x,+a.y), sinangle, cosangle).y)/aspect;
return float3((hi+lo)*aspect*0.5,max(hi.x-lo.x,hi.y-lo.y));
}
// Calculate the influence of a scanline on the current pixel.
//
// 'distance' is the distance in texture coordinates from the current
// pixel to the scanline in question.
// 'color' is the colour of the scanline at the horizontal location of
// the current pixel.
float4 scanlineWeights(float distance, float4 color)
{
// "wid" controls the width of the scanline beam, for each RGB
// channel The "weights" lines basically specify the formula
// that gives you the profile of the beam, i.e. the intensity as
// a function of distance from the vertical center of the
// scanline. In this case, it is gaussian if width=2, and
// becomes nongaussian for larger widths. Ideally this should
// be normalized so that the integral across the beam is
// independent of its width. That is, for a narrower beam
// "weights" should have a higher peak at the center of the
// scanline than for a wider beam.
#ifdef USEGAUSSIAN
float4 wid = 0.3 + 0.1 * pow(color, float4(3.0));
float4 weights = float4(distance / wid);
return 0.4 * exp(-weights * weights) / wid;
#else
float4 wid = 2.0 + 2.0 * pow(color, float4(4.0));
float4 weights = float4(distance / scanline_weight);
return 1.4 * exp(-pow(weights * rsqrt(0.5 * wid), wid)) / (0.6 + 0.2 * wid);
#endif
}
struct input
{
float2 tex_coord;
float2 video_size;
float2 texture_size;
float2 output_size;
float frame_count;
};
struct out_vertex {
float4 position : POSITION;
float4 color : COLOR;
float2 texCoord : TEXCOORD0;
float2 one;
float mod_factor;
float2 ilfac;
float3 stretch;
float2 sinangle;
float2 cosangle;
float2 TextureSize;
};
/* VERTEX_SHADER */
out_vertex main_vertex
(
float4 position : POSITION,
float4 color : COLOR,
float2 texCoord : TEXCOORD0,
uniform float4x4 modelViewProj,
uniform input IN
)
{
out_vertex OUT;
OUT.position = mul(modelViewProj, position);
OUT.color = color;
// Precalculate a bunch of useful values we'll need in the fragment
// shader.
OUT.sinangle = sin(float2(x_tilt, y_tilt));
OUT.cosangle = cos(float2(x_tilt, y_tilt));
OUT.stretch = maxscale(OUT.sinangle, OUT.cosangle);
OUT.texCoord = texCoord;
OUT.TextureSize = float2(SHARPER * IN.texture_size.x, IN.texture_size.y);
#ifdef INTERLACED
OUT.ilfac = float2(1.0,clamp(floor(IN.video_size.y/200.0),1.0,2.0));
#else
OUT.ilfac = float2(1.0,clamp(floor(IN.video_size.y/1000.0),1.0,2.0));
#endif
// The size of one texel, in texture-coordinates.
OUT.one = OUT.ilfac / OUT.TextureSize;
// Resulting X pixel-coordinate of the pixel we're drawing.
OUT.mod_factor = texCoord.x * IN.texture_size.x * IN.output_size.x / IN.video_size.x;
return OUT;
}
/* FRAGMENT SHADER */
float4 main_fragment(in out_vertex VAR, uniform input IN, uniform sampler2D s0 : TEXUNIT0) : COLOR
{
// Here's a helpful diagram to keep in mind while trying to
// understand the code:
//
// | | | | |
// -------------------------------
// | | | | |
// | 01 | 11 | 21 | 31 | <-- current scanline
// | | @ | | |
// -------------------------------
// | | | | |
// | 02 | 12 | 22 | 32 | <-- next scanline
// | | | | |
// -------------------------------
// | | | | |
//
// Each character-cell represents a pixel on the output
// surface, "@" represents the current pixel (always somewhere
// in the bottom half of the current scan-line, or the top-half
// of the next scanline). The grid of lines represents the
// edges of the texels of the underlying texture.
// Texture coordinates of the texel containing the active pixel.
float2 xy = 0.0;
if (CURVATURE > 0.5)
{
float2 cd = VAR.texCoord;
cd *= IN.texture_size / IN.video_size;
cd = (cd-float2(0.5))*aspect*VAR.stretch.z+VAR.stretch.xy;
xy = (bkwtrans(cd, VAR.sinangle, VAR.cosangle)/float2(overscan_x / 100.0, overscan_y / 100.0)/aspect+float2(0.5)) * IN.video_size / IN.texture_size;
}
else
{
xy = VAR.texCoord;
}
float2 cd2 = xy;
cd2 *= IN.texture_size / IN.video_size;
cd2 = (cd2 - float2(0.5)) * float2(overscan_x / 100.0, overscan_y / 100.0) + float2(0.5);
cd2 = min(cd2, float2(1.0)-cd2) * aspect;
float2 cdist = float2(cornersize);
cd2 = (cdist - min(cd2,cdist));
float dist = sqrt(dot(cd2,cd2));
float cval = clamp((cdist.x-dist)*cornersmooth,0.0, 1.0);
float2 xy2 = ((xy*VAR.TextureSize/IN.video_size-float2(0.5))*float2(1.0,1.0)+float2(0.5))*IN.video_size/VAR.TextureSize;
// Of all the pixels that are mapped onto the texel we are
// currently rendering, which pixel are we currently rendering?
float2 ilfloat = float2(0.0,VAR.ilfac.y > 1.5 ? fmod(float(IN.frame_count),2.0) : 0.0);
float2 ratio_scale = (xy * VAR.TextureSize - float2(0.5) + ilfloat)/VAR.ilfac;
#ifdef OVERSAMPLE
float filter = IN.video_size.y / IN.output_size.y;
#endif
float2 uv_ratio = frac(ratio_scale);
// Snap to the center of the underlying texel.
xy = (floor(ratio_scale)*VAR.ilfac + float2(0.5) - ilfloat) / VAR.TextureSize;
// Calculate Lanczos scaling coefficients describing the effect
// of various neighbour texels in a scanline on the current
// pixel.
float4 coeffs = PI * float4(1.0 + uv_ratio.x, uv_ratio.x, 1.0 - uv_ratio.x, 2.0 - uv_ratio.x);
// Prevent division by zero.
coeffs = FIX(coeffs);
// Lanczos2 kernel.
coeffs = 2.0 * sin(coeffs) * sin(coeffs / 2.0) / (coeffs * coeffs);
// Normalize.
coeffs /= dot(coeffs, float4(1.0));
// Calculate the effective colour of the current and next
// scanlines at the horizontal location of the current pixel,
// using the Lanczos coefficients above.
float4 col = clamp(mul(coeffs, float4x4(
TEX2D(xy + float2(-VAR.one.x, 0.0)),
TEX2D(xy),
TEX2D(xy + float2(VAR.one.x, 0.0)),
TEX2D(xy + float2(2.0 * VAR.one.x, 0.0)))),
0.0, 1.0);
float4 col2 = clamp(mul(coeffs, float4x4(
TEX2D(xy + float2(-VAR.one.x, VAR.one.y)),
TEX2D(xy + float2(0.0, VAR.one.y)),
TEX2D(xy + VAR.one),
TEX2D(xy + float2(2.0 * VAR.one.x, VAR.one.y)))),
0.0, 1.0);
#ifndef LINEAR_PROCESSING
col = pow(col , float4(CRTgamma));
col2 = pow(col2, float4(CRTgamma));
#endif
// Calculate the influence of the current and next scanlines on
// the current pixel.
float4 weights = scanlineWeights(uv_ratio.y, col);
float4 weights2 = scanlineWeights(1.0 - uv_ratio.y, col2);
#ifdef OVERSAMPLE
uv_ratio.y =uv_ratio.y+1.0/3.0*filter;
weights = (weights+scanlineWeights(uv_ratio.y, col))/3.0;
weights2=(weights2+scanlineWeights(abs(1.0-uv_ratio.y), col2))/3.0;
uv_ratio.y =uv_ratio.y-2.0/3.0*filter;
weights=weights+scanlineWeights(abs(uv_ratio.y), col)/3.0;
weights2=weights2+scanlineWeights(abs(1.0-uv_ratio.y), col2)/3.0;
#endif
float3 mul_res = (col * weights + col2 * weights2).rgb;
mul_res *= float3(cval);
// dot-mask emulation:
// Output pixels are alternately tinted green and magenta.
float3 dotMaskWeights = lerp(
float3(1.0, 1.0 - DOTMASK, 1.0),
float3(1.0 - DOTMASK, 1.0, 1.0 - DOTMASK),
floor(fmod(VAR.mod_factor, 2.0))
);
mul_res *= dotMaskWeights;
// Convert the image gamma for display on our output device.
mul_res = pow(mul_res, float3(1.0 / monitorgamma));
// Color the texel.
return float4(mul_res, 1.0);
}
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