<@include gpu/Config.slh@><$VERSION_HEADER$>//  Generated on <$_SCRIBE_DATE$>////  fxaa.frag//  fragment shader////  Created by Raffi Bedikian on 8/30/15//  Copyright 2015 High Fidelity, Inc.////  Distributed under the Apache License, Version 2.0.//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html// // FXAA shader, GLSL code adapted from:// http://horde3d.org/wiki/index.php5?title=Shading_Technique_-_FXAA// Whitepaper describing the technique:// http://developer.download.nvidia.com/assets/gamedev/files/sdk/11/FXAA_WhitePaper.pdf #ifdef GL_ESprecision mediump float;precision mediump int;#endif TEXTURE(0, sampler2D, colorTexture);//uniform sampler2D historyTexture; // FIXME make into a uniform buffer or push constant if this shader ever comes into usevec2 texcoordOffset = vec2(0.0); INPUT(0, vec2, varTexCoord0);OUTPUT(0, vec4, outFragColor);//OUTPUT(0, vec4, outFragHistory); void main() {    outFragColor = vec4(texture(colorTexture, varTexCoord0).xyz, 1.0/8.0);     // v2     /*   float ModulationFactor = 1.0 / 8.0;         vec3 History = textureLod(historyTexture, varTexCoord0, 0.0).rgb;        vec3 CurrentSubpixel = textureLod(colorTexture, varTexCoord0, 0.0).rgb;    /*        vec3 NearColor0 = textureLodOffset(colorTexture, varTexCoord0, 0.0, ivec2(1, 0)).xyz;        vec3 NearColor1 = textureLodOffset(colorTexture, varTexCoord0, 0.0, ivec2(0, 1)).xyz;        vec3 NearColor2 = textureLodOffset(colorTexture, varTexCoord0, 0.0, ivec2(-1, 0)).xyz;        vec3 NearColor3 = textureLodOffset(colorTexture, varTexCoord0, 0.0, ivec2(0, -1)).xyz;         vec3 BoxMin = min(CurrentSubpixel, min(NearColor0, min(NearColor1, min(NearColor2, NearColor3))));        vec3 BoxMax = max(CurrentSubpixel, max(NearColor0, max(NearColor1, max(NearColor2, NearColor3))));;         if (gl_FragCoord.x > 800) {            History = clamp(History, BoxMin, BoxMax);        }         History = mix(CurrentSubpixel, History, ModulationFactor);        /* outFragHistory.xyz = History;        outFragHistory.w = ModulationFactor         outFragColor.xyz = History;        outFragColor.w = 1.0;*/           /*  } else {              outFragColor.xyz = CurrentSubpixel;              outFragColor.w = 1.0;           }*/    if (gl_FragCoord.x > 800.0) {     /*  // filter width limit for dependent "two-tap" texture samples        float FXAA_SPAN_MAX = 8.0;         // local contrast multiplier for performing AA        // higher = sharper, but setting this value too high will cause near-vertical and near-horizontal edges to fail        // see "fxaaQualityEdgeThreshold"        float FXAA_REDUCE_MUL = 1.0 / 8.0;         // luminance threshold for processing dark colors        // see "fxaaQualityEdgeThresholdMin"        float FXAA_REDUCE_MIN = 1.0 / 128.0;         // fetch raw RGB values for nearby locations        // sampling pattern is "five on a die" (each diagonal direction and the center)        // computing the coordinates for these texture reads could be moved to the vertex shader for speed if needed        vec3 rgbNW = texture(colorTexture, varTexCoord0 + (vec2(-1.0, -1.0) * texcoordOffset)).xyz;        vec3 rgbNE = texture(colorTexture, varTexCoord0 + (vec2(+1.0, -1.0) * texcoordOffset)).xyz;        vec3 rgbSW = texture(colorTexture, varTexCoord0 + (vec2(-1.0, +1.0) * texcoordOffset)).xyz;        vec3 rgbSE = texture(colorTexture, varTexCoord0 + (vec2(+1.0, +1.0) * texcoordOffset)).xyz;        vec3 rgbM = texture(colorTexture, varTexCoord0).xyz;         // convert RGB values to luminance        vec3 luma = vec3(0.299, 0.587, 0.114);        float lumaNW = dot(rgbNW, luma);        float lumaNE = dot(rgbNE, luma);        float lumaSW = dot(rgbSW, luma);        float lumaSE = dot(rgbSE, luma);        float lumaM = dot(rgbM, luma);         // luma range of local neighborhood        float lumaMin = min(lumaM, min(min(lumaNW, lumaNE), min(lumaSW, lumaSE)));        float lumaMax = max(lumaM, max(max(lumaNW, lumaNE), max(lumaSW, lumaSE)));         // direction perpendicular to local luma gradient        vec2 dir;        dir.x = -((lumaNW + lumaNE) - (lumaSW + lumaSE));        dir.y = ((lumaNW + lumaSW) - (lumaNE + lumaSE));         // compute clamped direction offset for additional "two-tap" samples        // longer vector = blurry, shorter vector = sharp        float dirReduce = max((lumaNW + lumaNE + lumaSW + lumaSE) * (0.25 * FXAA_REDUCE_MUL), FXAA_REDUCE_MIN);        float rcpDirMin = 1.0 / (min(abs(dir.x), abs(dir.y)) + dirReduce);        dir = min(vec2(FXAA_SPAN_MAX, FXAA_SPAN_MAX),            max(vec2(-FXAA_SPAN_MAX, -FXAA_SPAN_MAX), dir * rcpDirMin)) * texcoordOffset;         // perform additional texture sampling perpendicular to gradient        vec3 rgbA = (1.0 / 2.0) * (            texture(colorTexture, varTexCoord0 + dir * (1.0 / 3.0 - 0.5)).xyz +            texture(colorTexture, varTexCoord0 + dir * (2.0 / 3.0 - 0.5)).xyz);        vec3 rgbB = rgbA * (1.0 / 2.0) + (1.0 / 4.0) * (            texture(colorTexture, varTexCoord0 + dir * (0.0 / 3.0 - 0.5)).xyz +            texture(colorTexture, varTexCoord0 + dir * (3.0 / 3.0 - 0.5)).xyz);        float lumaB = dot(rgbB, luma);         // compare luma of new samples to the luma range of the original neighborhood        // if the new samples exceed this range, just use the first two samples instead of all four        if (lumaB < lumaMin || lumaB > lumaMax) {            outFragColor.xyz = rgbA;        }        else {            outFragColor.xyz = rgbB;        }*/        outFragColor.a = 1.0;    }}