#ifndef BLUR_FUNCTIONS_H #define BLUR_FUNCTIONS_H ///////////////////////////////// MIT LICENSE //////////////////////////////// // Copyright (C) 2014 TroggleMonkey // // Permission is hereby granted, free of charge, to any person obtaining a copy // of this software and associated documentation files (the "Software"), to // deal in the Software without restriction, including without limitation the // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or // sell copies of the Software, and to permit persons to whom the Software is // furnished to do so, subject to the following conditions: // // The above copyright notice and this permission notice shall be included in // all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS // IN THE SOFTWARE. ///////////////////////////////// DESCRIPTION //////////////////////////////// // This file provides reusable one-pass and separable (two-pass) blurs. // Requires: All blurs share these requirements (dxdy requirement is split): // 1.) All requirements of gamma-management.h must be satisfied! // 2.) filter_linearN must == "true" in your .cgp preset unless // you're using tex2DblurNresize at 1x scale. // 3.) mipmap_inputN must == "true" in your .cgp preset if // IN.output_size < IN.video_size. // 4.) IN.output_size == IN.video_size / pow(2, M), where M is some // positive integer. tex2Dblur*resize can resize arbitrarily // (and the blur will be done after resizing), but arbitrary // resizes "fail" with other blurs due to the way they mix // static weights with bilinear sample exploitation. // 5.) In general, dxdy should contain the uv pixel spacing: // dxdy = (IN.video_size/IN.output_size)/IN.texture_size // 6.) For separable blurs (tex2DblurNresize and tex2DblurNfast), // zero out the dxdy component in the unblurred dimension: // dxdy = vec2(dxdy.x, 0.0) or vec2(0.0, dxdy.y) // Many blurs share these requirements: // 1.) One-pass blurs require scale_xN == scale_yN or scales > 1.0, // or they will blur more in the lower-scaled dimension. // 2.) One-pass shared sample blurs require ddx(), ddy(), and // tex2Dlod() to be supported by the current Cg profile, and // the drivers must support high-quality derivatives. // 3.) One-pass shared sample blurs require: // tex_uv.w == log2(IN.video_size/IN.output_size).y; // Non-wrapper blurs share this requirement: // 1.) sigma is the intended standard deviation of the blur // Wrapper blurs share this requirement, which is automatically // met (unless OVERRIDE_BLUR_STD_DEVS is #defined; see below): // 1.) blurN_std_dev must be global static const float values // specifying standard deviations for Nx blurs in units // of destination pixels // Optional: 1.) The including file (or an earlier included file) may // optionally #define USE_BINOMIAL_BLUR_STD_DEVS to replace // default standard deviations with those matching a binomial // distribution. (See below for details/properties.) // 2.) The including file (or an earlier included file) may // optionally #define OVERRIDE_BLUR_STD_DEVS and override: // static const float blur3_std_dev // static const float blur4_std_dev // static const float blur5_std_dev // static const float blur6_std_dev // static const float blur7_std_dev // static const float blur8_std_dev // static const float blur9_std_dev // static const float blur10_std_dev // static const float blur11_std_dev // static const float blur12_std_dev // static const float blur17_std_dev // static const float blur25_std_dev // static const float blur31_std_dev // static const float blur43_std_dev // 3.) The including file (or an earlier included file) may // optionally #define OVERRIDE_ERROR_BLURRING and override: // static const float error_blurring // This tuning value helps mitigate weighting errors from one- // pass shared-sample blurs sharing bilinear samples between // fragments. Values closer to 0.0 have "correct" blurriness // but allow more artifacts, and values closer to 1.0 blur away // artifacts by sampling closer to halfway between texels. // UPDATE 6/21/14: The above static constants may now be overridden // by non-static uniform constants. This permits exposing blur // standard deviations as runtime GUI shader parameters. However, // using them keeps weights from being statically computed, and the // speed hit depends on the blur: On my machine, uniforms kill over // 53% of the framerate with tex2Dblur12x12shared, but they only // drop the framerate by about 18% with tex2Dblur11fast. // Quality and Performance Comparisons: // For the purposes of the following discussion, "no sRGB" means // GAMMA_ENCODE_EVERY_FBO is #defined, and "sRGB" means it isn't. // 1.) tex2DblurNfast is always faster than tex2DblurNresize. // 2.) tex2DblurNresize functions are the only ones that can arbitrarily resize // well, because they're the only ones that don't exploit bilinear samples. // This also means they're the only functions which can be truly gamma- // correct without linear (or sRGB FBO) input, but only at 1x scale. // 3.) One-pass shared sample blurs only have a speed advantage without sRGB. // They also have some inaccuracies due to their shared-[bilinear-]sample // design, which grow increasingly bothersome for smaller blurs and higher- // frequency source images (relative to their resolution). I had high // hopes for them, but their most realistic use case is limited to quickly // reblurring an already blurred input at full resolution. Otherwise: // a.) If you're blurring a low-resolution source, you want a better blur. // b.) If you're blurring a lower mipmap, you want a better blur. // c.) If you're blurring a high-resolution, high-frequency source, you // want a better blur. // 4.) The one-pass blurs without shared samples grow slower for larger blurs, // but they're competitive with separable blurs at 5x5 and smaller, and // even tex2Dblur7x7 isn't bad if you're wanting to conserve passes. // Here are some framerates from a GeForce 8800GTS. The first pass resizes to // viewport size (4x in this test) and linearizes for sRGB codepaths, and the // remaining passes perform 6 full blurs. Mipmapped tests are performed at the // same scale, so they just measure the cost of mipmapping each FBO (only every // other FBO is mipmapped for separable blurs, to mimic realistic usage). // Mipmap Neither sRGB+Mipmap sRGB Function // 76.0 92.3 131.3 193.7 tex2Dblur3fast // 63.2 74.4 122.4 175.5 tex2Dblur3resize // 93.7 121.2 159.3 263.2 tex2Dblur3x3 // 59.7 68.7 115.4 162.1 tex2Dblur3x3resize // 63.2 74.4 122.4 175.5 tex2Dblur5fast // 49.3 54.8 100.0 132.7 tex2Dblur5resize // 59.7 68.7 115.4 162.1 tex2Dblur5x5 // 64.9 77.2 99.1 137.2 tex2Dblur6x6shared // 55.8 63.7 110.4 151.8 tex2Dblur7fast // 39.8 43.9 83.9 105.8 tex2Dblur7resize // 40.0 44.2 83.2 104.9 tex2Dblur7x7 // 56.4 65.5 71.9 87.9 tex2Dblur8x8shared // 49.3 55.1 99.9 132.5 tex2Dblur9fast // 33.3 36.2 72.4 88.0 tex2Dblur9resize // 27.8 29.7 61.3 72.2 tex2Dblur9x9 // 37.2 41.1 52.6 60.2 tex2Dblur10x10shared // 44.4 49.5 91.3 117.8 tex2Dblur11fast // 28.8 30.8 63.6 75.4 tex2Dblur11resize // 33.6 36.5 40.9 45.5 tex2Dblur12x12shared // TODO: Fill in benchmarks for new untested blurs. // tex2Dblur17fast // tex2Dblur25fast // tex2Dblur31fast // tex2Dblur43fast // tex2Dblur3x3resize ///////////////////////////// SETTINGS MANAGEMENT //////////////////////////// // Set static standard deviations, but allow users to override them with their // own constants (even non-static uniforms if they're okay with the speed hit): #ifndef OVERRIDE_BLUR_STD_DEVS // blurN_std_dev values are specified in terms of dxdy strides. #ifdef USE_BINOMIAL_BLUR_STD_DEVS // By request, we can define standard deviations corresponding to a // binomial distribution with p = 0.5 (related to Pascal's triangle). // This distribution works such that blurring multiple times should // have the same result as a single larger blur. These values are // larger than default for blurs up to 6x and smaller thereafter. const float blur3_std_dev = 0.84931640625; const float blur4_std_dev = 0.84931640625; const float blur5_std_dev = 1.0595703125; const float blur6_std_dev = 1.06591796875; const float blur7_std_dev = 1.17041015625; const float blur8_std_dev = 1.1720703125; const float blur9_std_dev = 1.2259765625; const float blur10_std_dev = 1.21982421875; const float blur11_std_dev = 1.25361328125; const float blur12_std_dev = 1.2423828125; const float blur17_std_dev = 1.27783203125; const float blur25_std_dev = 1.2810546875; const float blur31_std_dev = 1.28125; const float blur43_std_dev = 1.28125; #else // The defaults are the largest values that keep the largest unused // blur term on each side <= 1.0/256.0. (We could get away with more // or be more conservative, but this compromise is pretty reasonable.) const float blur3_std_dev = 0.62666015625; const float blur4_std_dev = 0.66171875; const float blur5_std_dev = 0.9845703125; const float blur6_std_dev = 1.02626953125; const float blur7_std_dev = 1.36103515625; const float blur8_std_dev = 1.4080078125; const float blur9_std_dev = 1.7533203125; const float blur10_std_dev = 1.80478515625; const float blur11_std_dev = 2.15986328125; const float blur12_std_dev = 2.215234375; const float blur17_std_dev = 3.45535583496; const float blur25_std_dev = 5.3409576416; const float blur31_std_dev = 6.86488037109; const float blur43_std_dev = 10.1852050781; #endif // USE_BINOMIAL_BLUR_STD_DEVS #endif // OVERRIDE_BLUR_STD_DEVS #ifndef OVERRIDE_ERROR_BLURRING // error_blurring should be in [0.0, 1.0]. Higher values reduce ringing // in shared-sample blurs but increase blurring and feature shifting. const float error_blurring = 0.5; #endif // Make a length squared helper macro (for usage with static constants): #define LENGTH_SQ(vec) (dot(vec, vec)) ////////////////////////////////// INCLUDES ////////////////////////////////// // gamma-management.h relies on pass-specific settings to guide its behavior: // FIRST_PASS, LAST_PASS, GAMMA_ENCODE_EVERY_FBO, etc. See it for details. #include "gamma-management.h" //#include "quad-pixel-communication.h" #include "special-functions.h" /////////////////////////////////// HELPERS ////////////////////////////////// vec4 uv2_to_uv4(vec2 tex_uv) { // Make a vec2 uv offset safe for adding to vec4 tex2Dlod coords: return vec4(tex_uv, 0.0, 0.0); } // Make a length squared helper macro (for usage with static constants): #define LENGTH_SQ(vec) (dot(vec, vec)) float get_fast_gaussian_weight_sum_inv(const float sigma) { // We can use the Gaussian integral to calculate the asymptotic weight for // the center pixel. Since the unnormalized center pixel weight is 1.0, // the normalized weight is the same as the weight sum inverse. Given a // large enough blur (9+), the asymptotic weight sum is close and faster: // center_weight = 0.5 * // (erf(0.5/(sigma*sqrt(2.0))) - erf(-0.5/(sigma*sqrt(2.0)))) // erf(-x) == -erf(x), so we get 0.5 * (2.0 * erf(blah blah)): // However, we can get even faster results with curve-fitting. These are // also closer than the asymptotic results, because they were constructed // from 64 blurs sizes from [3, 131) and 255 equally-spaced sigmas from // (0, blurN_std_dev), so the results for smaller sigmas are biased toward // smaller blurs. The max error is 0.0031793913. // Relative FPS: 134.3 with erf, 135.8 with curve-fitting. //static const float temp = 0.5/sqrt(2.0); //return erf(temp/sigma); return min(exp(exp(0.348348412457428/ (sigma - 0.0860587260734721))), 0.399334576340352/sigma); } //////////////////// ARBITRARILY RESIZABLE SEPARABLE BLURS /////////////////// vec3 tex2Dblur11resize(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Global requirements must be met (see file description). // Returns: A 1D 11x Gaussian blurred texture lookup using a 11-tap blur. // It may be mipmapped depending on settings and dxdy. // Calculate Gaussian blur kernel weights and a normalization factor for // distances of 0-4, ignoring constant factors (since we're normalizing). const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float w3 = exp(-9.0 * denom_inv); const float w4 = exp(-16.0 * denom_inv); const float w5 = exp(-25.0 * denom_inv); const float weight_sum_inv = 1.0 / (w0 + 2.0 * (w1 + w2 + w3 + w4 + w5)); // Statically normalize weights, sum weighted samples, and return. Blurs are // currently optimized for dynamic weights. vec3 sum = vec3(0.0); sum += w5 * tex2D_linearize(tex, tex_uv - 5.0 * dxdy).rgb; sum += w4 * tex2D_linearize(tex, tex_uv - 4.0 * dxdy).rgb; sum += w3 * tex2D_linearize(tex, tex_uv - 3.0 * dxdy).rgb; sum += w2 * tex2D_linearize(tex, tex_uv - 2.0 * dxdy).rgb; sum += w1 * tex2D_linearize(tex, tex_uv - 1.0 * dxdy).rgb; sum += w0 * tex2D_linearize(tex, tex_uv).rgb; sum += w1 * tex2D_linearize(tex, tex_uv + 1.0 * dxdy).rgb; sum += w2 * tex2D_linearize(tex, tex_uv + 2.0 * dxdy).rgb; sum += w3 * tex2D_linearize(tex, tex_uv + 3.0 * dxdy).rgb; sum += w4 * tex2D_linearize(tex, tex_uv + 4.0 * dxdy).rgb; sum += w5 * tex2D_linearize(tex, tex_uv + 5.0 * dxdy).rgb; return sum * weight_sum_inv; } vec3 tex2Dblur9resize(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Global requirements must be met (see file description). // Returns: A 1D 9x Gaussian blurred texture lookup using a 9-tap blur. // It may be mipmapped depending on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float w3 = exp(-9.0 * denom_inv); const float w4 = exp(-16.0 * denom_inv); const float weight_sum_inv = 1.0 / (w0 + 2.0 * (w1 + w2 + w3 + w4)); // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w4 * tex2D_linearize(tex, tex_uv - 4.0 * dxdy).rgb; sum += w3 * tex2D_linearize(tex, tex_uv - 3.0 * dxdy).rgb; sum += w2 * tex2D_linearize(tex, tex_uv - 2.0 * dxdy).rgb; sum += w1 * tex2D_linearize(tex, tex_uv - 1.0 * dxdy).rgb; sum += w0 * tex2D_linearize(tex, tex_uv).rgb; sum += w1 * tex2D_linearize(tex, tex_uv + 1.0 * dxdy).rgb; sum += w2 * tex2D_linearize(tex, tex_uv + 2.0 * dxdy).rgb; sum += w3 * tex2D_linearize(tex, tex_uv + 3.0 * dxdy).rgb; sum += w4 * tex2D_linearize(tex, tex_uv + 4.0 * dxdy).rgb; return sum * weight_sum_inv; } vec3 tex2Dblur7resize(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Global requirements must be met (see file description). // Returns: A 1D 7x Gaussian blurred texture lookup using a 7-tap blur. // It may be mipmapped depending on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float w3 = exp(-9.0 * denom_inv); const float weight_sum_inv = 1.0 / (w0 + 2.0 * (w1 + w2 + w3)); // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w3 * tex2D_linearize(tex, tex_uv - 3.0 * dxdy).rgb; sum += w2 * tex2D_linearize(tex, tex_uv - 2.0 * dxdy).rgb; sum += w1 * tex2D_linearize(tex, tex_uv - 1.0 * dxdy).rgb; sum += w0 * tex2D_linearize(tex, tex_uv).rgb; sum += w1 * tex2D_linearize(tex, tex_uv + 1.0 * dxdy).rgb; sum += w2 * tex2D_linearize(tex, tex_uv + 2.0 * dxdy).rgb; sum += w3 * tex2D_linearize(tex, tex_uv + 3.0 * dxdy).rgb; return sum * weight_sum_inv; } vec3 tex2Dblur5resize(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Global requirements must be met (see file description). // Returns: A 1D 5x Gaussian blurred texture lookup using a 5-tap blur. // It may be mipmapped depending on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float weight_sum_inv = 1.0 / (w0 + 2.0 * (w1 + w2)); // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w2 * tex2D_linearize(tex, tex_uv - 2.0 * dxdy).rgb; sum += w1 * tex2D_linearize(tex, tex_uv - 1.0 * dxdy).rgb; sum += w0 * tex2D_linearize(tex, tex_uv).rgb; sum += w1 * tex2D_linearize(tex, tex_uv + 1.0 * dxdy).rgb; sum += w2 * tex2D_linearize(tex, tex_uv + 2.0 * dxdy).rgb; return sum * weight_sum_inv; } vec3 tex2Dblur3resize(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Global requirements must be met (see file description). // Returns: A 1D 3x Gaussian blurred texture lookup using a 3-tap blur. // It may be mipmapped depending on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float weight_sum_inv = 1.0 / (w0 + 2.0 * w1); // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w1 * tex2D_linearize(tex, tex_uv - 1.0 * dxdy).rgb; sum += w0 * tex2D_linearize(tex, tex_uv).rgb; sum += w1 * tex2D_linearize(tex, tex_uv + 1.0 * dxdy).rgb; return sum * weight_sum_inv; } /////////////////////////// FAST SEPARABLE BLURS /////////////////////////// vec3 tex2Dblur11fast(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: 1.) Global requirements must be met (see file description). // 2.) filter_linearN must = "true" in your .cgp file. // 3.) For gamma-correct bilinear filtering, global // gamma_aware_bilinear == true (from gamma-management.h) // Returns: A 1D 11x Gaussian blurred texture lookup using 6 linear // taps. It may be mipmapped depending on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float w3 = exp(-9.0 * denom_inv); const float w4 = exp(-16.0 * denom_inv); const float w5 = exp(-25.0 * denom_inv); const float weight_sum_inv = 1.0 / (w0 + 2.0 * (w1 + w2 + w3 + w4 + w5)); // Calculate combined weights and linear sample ratios between texel pairs. // The center texel (with weight w0) is used twice, so halve its weight. const float w01 = w0 * 0.5 + w1; const float w23 = w2 + w3; const float w45 = w4 + w5; const float w01_ratio = w1/w01; const float w23_ratio = w3/w23; const float w45_ratio = w5/w45; // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w45 * tex2D_linearize(tex, tex_uv - (4.0 + w45_ratio) * dxdy).rgb; sum += w23 * tex2D_linearize(tex, tex_uv - (2.0 + w23_ratio) * dxdy).rgb; sum += w01 * tex2D_linearize(tex, tex_uv - w01_ratio * dxdy).rgb; sum += w01 * tex2D_linearize(tex, tex_uv + w01_ratio * dxdy).rgb; sum += w23 * tex2D_linearize(tex, tex_uv + (2.0 + w23_ratio) * dxdy).rgb; sum += w45 * tex2D_linearize(tex, tex_uv + (4.0 + w45_ratio) * dxdy).rgb; return sum * weight_sum_inv; } vec3 tex2Dblur17fast(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Same as tex2Dblur11() // Returns: A 1D 17x Gaussian blurred texture lookup using 1 nearest // neighbor and 8 linear taps. It may be mipmapped depending // on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float w3 = exp(-9.0 * denom_inv); const float w4 = exp(-16.0 * denom_inv); const float w5 = exp(-25.0 * denom_inv); const float w6 = exp(-36.0 * denom_inv); const float w7 = exp(-49.0 * denom_inv); const float w8 = exp(-64.0 * denom_inv); //const float weight_sum_inv = 1.0 / (w0 + 2.0 * ( // w1 + w2 + w3 + w4 + w5 + w6 + w7 + w8)); const float weight_sum_inv = get_fast_gaussian_weight_sum_inv(sigma); // Calculate combined weights and linear sample ratios between texel pairs. const float w1_2 = w1 + w2; const float w3_4 = w3 + w4; const float w5_6 = w5 + w6; const float w7_8 = w7 + w8; const float w1_2_ratio = w2/w1_2; const float w3_4_ratio = w4/w3_4; const float w5_6_ratio = w6/w5_6; const float w7_8_ratio = w8/w7_8; // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w7_8 * tex2D_linearize(tex, tex_uv - (7.0 + w7_8_ratio) * dxdy).rgb; sum += w5_6 * tex2D_linearize(tex, tex_uv - (5.0 + w5_6_ratio) * dxdy).rgb; sum += w3_4 * tex2D_linearize(tex, tex_uv - (3.0 + w3_4_ratio) * dxdy).rgb; sum += w1_2 * tex2D_linearize(tex, tex_uv - (1.0 + w1_2_ratio) * dxdy).rgb; sum += w0 * tex2D_linearize(tex, tex_uv).rgb; sum += w1_2 * tex2D_linearize(tex, tex_uv + (1.0 + w1_2_ratio) * dxdy).rgb; sum += w3_4 * tex2D_linearize(tex, tex_uv + (3.0 + w3_4_ratio) * dxdy).rgb; sum += w5_6 * tex2D_linearize(tex, tex_uv + (5.0 + w5_6_ratio) * dxdy).rgb; sum += w7_8 * tex2D_linearize(tex, tex_uv + (7.0 + w7_8_ratio) * dxdy).rgb; return sum * weight_sum_inv; } vec3 tex2Dblur25fast(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Same as tex2Dblur11() // Returns: A 1D 25x Gaussian blurred texture lookup using 1 nearest // neighbor and 12 linear taps. It may be mipmapped depending // on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float w3 = exp(-9.0 * denom_inv); const float w4 = exp(-16.0 * denom_inv); const float w5 = exp(-25.0 * denom_inv); const float w6 = exp(-36.0 * denom_inv); const float w7 = exp(-49.0 * denom_inv); const float w8 = exp(-64.0 * denom_inv); const float w9 = exp(-81.0 * denom_inv); const float w10 = exp(-100.0 * denom_inv); const float w11 = exp(-121.0 * denom_inv); const float w12 = exp(-144.0 * denom_inv); //const float weight_sum_inv = 1.0 / (w0 + 2.0 * ( // w1 + w2 + w3 + w4 + w5 + w6 + w7 + w8 + w9 + w10 + w11 + w12)); const float weight_sum_inv = get_fast_gaussian_weight_sum_inv(sigma); // Calculate combined weights and linear sample ratios between texel pairs. const float w1_2 = w1 + w2; const float w3_4 = w3 + w4; const float w5_6 = w5 + w6; const float w7_8 = w7 + w8; const float w9_10 = w9 + w10; const float w11_12 = w11 + w12; const float w1_2_ratio = w2/w1_2; const float w3_4_ratio = w4/w3_4; const float w5_6_ratio = w6/w5_6; const float w7_8_ratio = w8/w7_8; const float w9_10_ratio = w10/w9_10; const float w11_12_ratio = w12/w11_12; // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w11_12 * tex2D_linearize(tex, tex_uv - (11.0 + w11_12_ratio) * dxdy).rgb; sum += w9_10 * tex2D_linearize(tex, tex_uv - (9.0 + w9_10_ratio) * dxdy).rgb; sum += w7_8 * tex2D_linearize(tex, tex_uv - (7.0 + w7_8_ratio) * dxdy).rgb; sum += w5_6 * tex2D_linearize(tex, tex_uv - (5.0 + w5_6_ratio) * dxdy).rgb; sum += w3_4 * tex2D_linearize(tex, tex_uv - (3.0 + w3_4_ratio) * dxdy).rgb; sum += w1_2 * tex2D_linearize(tex, tex_uv - (1.0 + w1_2_ratio) * dxdy).rgb; sum += w0 * tex2D_linearize(tex, tex_uv).rgb; sum += w1_2 * tex2D_linearize(tex, tex_uv + (1.0 + w1_2_ratio) * dxdy).rgb; sum += w3_4 * tex2D_linearize(tex, tex_uv + (3.0 + w3_4_ratio) * dxdy).rgb; sum += w5_6 * tex2D_linearize(tex, tex_uv + (5.0 + w5_6_ratio) * dxdy).rgb; sum += w7_8 * tex2D_linearize(tex, tex_uv + (7.0 + w7_8_ratio) * dxdy).rgb; sum += w9_10 * tex2D_linearize(tex, tex_uv + (9.0 + w9_10_ratio) * dxdy).rgb; sum += w11_12 * tex2D_linearize(tex, tex_uv + (11.0 + w11_12_ratio) * dxdy).rgb; return sum * weight_sum_inv; } vec3 tex2Dblur31fast(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Same as tex2Dblur11() // Returns: A 1D 31x Gaussian blurred texture lookup using 16 linear // taps. It may be mipmapped depending on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float w3 = exp(-9.0 * denom_inv); const float w4 = exp(-16.0 * denom_inv); const float w5 = exp(-25.0 * denom_inv); const float w6 = exp(-36.0 * denom_inv); const float w7 = exp(-49.0 * denom_inv); const float w8 = exp(-64.0 * denom_inv); const float w9 = exp(-81.0 * denom_inv); const float w10 = exp(-100.0 * denom_inv); const float w11 = exp(-121.0 * denom_inv); const float w12 = exp(-144.0 * denom_inv); const float w13 = exp(-169.0 * denom_inv); const float w14 = exp(-196.0 * denom_inv); const float w15 = exp(-225.0 * denom_inv); //const float weight_sum_inv = 1.0 / // (w0 + 2.0 * (w1 + w2 + w3 + w4 + w5 + w6 + w7 + w8 + // w9 + w10 + w11 + w12 + w13 + w14 + w15)); const float weight_sum_inv = get_fast_gaussian_weight_sum_inv(sigma); // Calculate combined weights and linear sample ratios between texel pairs. // The center texel (with weight w0) is used twice, so halve its weight. const float w0_1 = w0 * 0.5 + w1; const float w2_3 = w2 + w3; const float w4_5 = w4 + w5; const float w6_7 = w6 + w7; const float w8_9 = w8 + w9; const float w10_11 = w10 + w11; const float w12_13 = w12 + w13; const float w14_15 = w14 + w15; const float w0_1_ratio = w1/w0_1; const float w2_3_ratio = w3/w2_3; const float w4_5_ratio = w5/w4_5; const float w6_7_ratio = w7/w6_7; const float w8_9_ratio = w9/w8_9; const float w10_11_ratio = w11/w10_11; const float w12_13_ratio = w13/w12_13; const float w14_15_ratio = w15/w14_15; // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w14_15 * tex2D_linearize(tex, tex_uv - (14.0 + w14_15_ratio) * dxdy).rgb; sum += w12_13 * tex2D_linearize(tex, tex_uv - (12.0 + w12_13_ratio) * dxdy).rgb; sum += w10_11 * tex2D_linearize(tex, tex_uv - (10.0 + w10_11_ratio) * dxdy).rgb; sum += w8_9 * tex2D_linearize(tex, tex_uv - (8.0 + w8_9_ratio) * dxdy).rgb; sum += w6_7 * tex2D_linearize(tex, tex_uv - (6.0 + w6_7_ratio) * dxdy).rgb; sum += w4_5 * tex2D_linearize(tex, tex_uv - (4.0 + w4_5_ratio) * dxdy).rgb; sum += w2_3 * tex2D_linearize(tex, tex_uv - (2.0 + w2_3_ratio) * dxdy).rgb; sum += w0_1 * tex2D_linearize(tex, tex_uv - w0_1_ratio * dxdy).rgb; sum += w0_1 * tex2D_linearize(tex, tex_uv + w0_1_ratio * dxdy).rgb; sum += w2_3 * tex2D_linearize(tex, tex_uv + (2.0 + w2_3_ratio) * dxdy).rgb; sum += w4_5 * tex2D_linearize(tex, tex_uv + (4.0 + w4_5_ratio) * dxdy).rgb; sum += w6_7 * tex2D_linearize(tex, tex_uv + (6.0 + w6_7_ratio) * dxdy).rgb; sum += w8_9 * tex2D_linearize(tex, tex_uv + (8.0 + w8_9_ratio) * dxdy).rgb; sum += w10_11 * tex2D_linearize(tex, tex_uv + (10.0 + w10_11_ratio) * dxdy).rgb; sum += w12_13 * tex2D_linearize(tex, tex_uv + (12.0 + w12_13_ratio) * dxdy).rgb; sum += w14_15 * tex2D_linearize(tex, tex_uv + (14.0 + w14_15_ratio) * dxdy).rgb; return sum * weight_sum_inv; } vec3 tex2Dblur43fast(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Same as tex2Dblur11() // Returns: A 1D 43x Gaussian blurred texture lookup using 22 linear // taps. It may be mipmapped depending on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float w3 = exp(-9.0 * denom_inv); const float w4 = exp(-16.0 * denom_inv); const float w5 = exp(-25.0 * denom_inv); const float w6 = exp(-36.0 * denom_inv); const float w7 = exp(-49.0 * denom_inv); const float w8 = exp(-64.0 * denom_inv); const float w9 = exp(-81.0 * denom_inv); const float w10 = exp(-100.0 * denom_inv); const float w11 = exp(-121.0 * denom_inv); const float w12 = exp(-144.0 * denom_inv); const float w13 = exp(-169.0 * denom_inv); const float w14 = exp(-196.0 * denom_inv); const float w15 = exp(-225.0 * denom_inv); const float w16 = exp(-256.0 * denom_inv); const float w17 = exp(-289.0 * denom_inv); const float w18 = exp(-324.0 * denom_inv); const float w19 = exp(-361.0 * denom_inv); const float w20 = exp(-400.0 * denom_inv); const float w21 = exp(-441.0 * denom_inv); //const float weight_sum_inv = 1.0 / // (w0 + 2.0 * (w1 + w2 + w3 + w4 + w5 + w6 + w7 + w8 + w9 + w10 + w11 + // w12 + w13 + w14 + w15 + w16 + w17 + w18 + w19 + w20 + w21)); const float weight_sum_inv = get_fast_gaussian_weight_sum_inv(sigma); // Calculate combined weights and linear sample ratios between texel pairs. // The center texel (with weight w0) is used twice, so halve its weight. const float w0_1 = w0 * 0.5 + w1; const float w2_3 = w2 + w3; const float w4_5 = w4 + w5; const float w6_7 = w6 + w7; const float w8_9 = w8 + w9; const float w10_11 = w10 + w11; const float w12_13 = w12 + w13; const float w14_15 = w14 + w15; const float w16_17 = w16 + w17; const float w18_19 = w18 + w19; const float w20_21 = w20 + w21; const float w0_1_ratio = w1/w0_1; const float w2_3_ratio = w3/w2_3; const float w4_5_ratio = w5/w4_5; const float w6_7_ratio = w7/w6_7; const float w8_9_ratio = w9/w8_9; const float w10_11_ratio = w11/w10_11; const float w12_13_ratio = w13/w12_13; const float w14_15_ratio = w15/w14_15; const float w16_17_ratio = w17/w16_17; const float w18_19_ratio = w19/w18_19; const float w20_21_ratio = w21/w20_21; // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w20_21 * tex2D_linearize(tex, tex_uv - (20.0 + w20_21_ratio) * dxdy).rgb; sum += w18_19 * tex2D_linearize(tex, tex_uv - (18.0 + w18_19_ratio) * dxdy).rgb; sum += w16_17 * tex2D_linearize(tex, tex_uv - (16.0 + w16_17_ratio) * dxdy).rgb; sum += w14_15 * tex2D_linearize(tex, tex_uv - (14.0 + w14_15_ratio) * dxdy).rgb; sum += w12_13 * tex2D_linearize(tex, tex_uv - (12.0 + w12_13_ratio) * dxdy).rgb; sum += w10_11 * tex2D_linearize(tex, tex_uv - (10.0 + w10_11_ratio) * dxdy).rgb; sum += w8_9 * tex2D_linearize(tex, tex_uv - (8.0 + w8_9_ratio) * dxdy).rgb; sum += w6_7 * tex2D_linearize(tex, tex_uv - (6.0 + w6_7_ratio) * dxdy).rgb; sum += w4_5 * tex2D_linearize(tex, tex_uv - (4.0 + w4_5_ratio) * dxdy).rgb; sum += w2_3 * tex2D_linearize(tex, tex_uv - (2.0 + w2_3_ratio) * dxdy).rgb; sum += w0_1 * tex2D_linearize(tex, tex_uv - w0_1_ratio * dxdy).rgb; sum += w0_1 * tex2D_linearize(tex, tex_uv + w0_1_ratio * dxdy).rgb; sum += w2_3 * tex2D_linearize(tex, tex_uv + (2.0 + w2_3_ratio) * dxdy).rgb; sum += w4_5 * tex2D_linearize(tex, tex_uv + (4.0 + w4_5_ratio) * dxdy).rgb; sum += w6_7 * tex2D_linearize(tex, tex_uv + (6.0 + w6_7_ratio) * dxdy).rgb; sum += w8_9 * tex2D_linearize(tex, tex_uv + (8.0 + w8_9_ratio) * dxdy).rgb; sum += w10_11 * tex2D_linearize(tex, tex_uv + (10.0 + w10_11_ratio) * dxdy).rgb; sum += w12_13 * tex2D_linearize(tex, tex_uv + (12.0 + w12_13_ratio) * dxdy).rgb; sum += w14_15 * tex2D_linearize(tex, tex_uv + (14.0 + w14_15_ratio) * dxdy).rgb; sum += w16_17 * tex2D_linearize(tex, tex_uv + (16.0 + w16_17_ratio) * dxdy).rgb; sum += w18_19 * tex2D_linearize(tex, tex_uv + (18.0 + w18_19_ratio) * dxdy).rgb; sum += w20_21 * tex2D_linearize(tex, tex_uv + (20.0 + w20_21_ratio) * dxdy).rgb; return sum * weight_sum_inv; } vec3 tex2Dblur3fast(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Same as tex2Dblur11() // Returns: A 1D 3x Gaussian blurred texture lookup using 2 linear // taps. It may be mipmapped depending on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float weight_sum_inv = 1.0 / (w0 + 2.0 * w1); // Calculate combined weights and linear sample ratios between texel pairs. // The center texel (with weight w0) is used twice, so halve its weight. const float w01 = w0 * 0.5 + w1; const float w01_ratio = w1/w01; // Weights for all samples are the same, so just average them: return 0.5 * ( tex2D_linearize(tex, tex_uv - w01_ratio * dxdy).rgb + tex2D_linearize(tex, tex_uv + w01_ratio * dxdy).rgb); } vec3 tex2Dblur5fast(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Same as tex2Dblur11() // Returns: A 1D 5x Gaussian blurred texture lookup using 1 nearest // neighbor and 2 linear taps. It may be mipmapped depending // on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float weight_sum_inv = 1.0 / (w0 + 2.0 * (w1 + w2)); // Calculate combined weights and linear sample ratios between texel pairs. const float w12 = w1 + w2; const float w12_ratio = w2/w12; // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w12 * tex2D_linearize(tex, tex_uv - (1.0 + w12_ratio) * dxdy).rgb; sum += w0 * tex2D_linearize(tex, tex_uv).rgb; sum += w12 * tex2D_linearize(tex, tex_uv + (1.0 + w12_ratio) * dxdy).rgb; return sum * weight_sum_inv; } vec3 tex2Dblur7fast(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Same as tex2Dblur11() // Returns: A 1D 7x Gaussian blurred texture lookup using 4 linear // taps. It may be mipmapped depending on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float w3 = exp(-9.0 * denom_inv); const float weight_sum_inv = 1.0 / (w0 + 2.0 * (w1 + w2 + w3)); // Calculate combined weights and linear sample ratios between texel pairs. // The center texel (with weight w0) is used twice, so halve its weight. const float w01 = w0 * 0.5 + w1; const float w23 = w2 + w3; const float w01_ratio = w1/w01; const float w23_ratio = w3/w23; // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w23 * tex2D_linearize(tex, tex_uv - (2.0 + w23_ratio) * dxdy).rgb; sum += w01 * tex2D_linearize(tex, tex_uv - w01_ratio * dxdy).rgb; sum += w01 * tex2D_linearize(tex, tex_uv + w01_ratio * dxdy).rgb; sum += w23 * tex2D_linearize(tex, tex_uv + (2.0 + w23_ratio) * dxdy).rgb; return sum * weight_sum_inv; } //////////////////// ARBITRARILY RESIZABLE ONE-PASS BLURS //////////////////// vec3 tex2Dblur3x3resize(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Global requirements must be met (see file description). // Returns: A 3x3 Gaussian blurred mipmapped texture lookup of the // resized input. // Description: // This is the only arbitrarily resizable one-pass blur; tex2Dblur5x5resize // would perform like tex2Dblur9x9, MUCH slower than tex2Dblur5resize. const float denom_inv = 0.5/(sigma*sigma); // Load each sample. We need all 3x3 samples. Quad-pixel communication // won't help either: This should perform like tex2Dblur5x5, but sharing a // 4x4 sample field would perform more like tex2Dblur8x8shared (worse). const vec2 sample4_uv = tex_uv; const vec2 dx = vec2(dxdy.x, 0.0); const vec2 dy = vec2(0.0, dxdy.y); const vec2 sample1_uv = sample4_uv - dy; const vec2 sample7_uv = sample4_uv + dy; const vec3 sample0 = tex2D_linearize(tex, sample1_uv - dx).rgb; const vec3 sample1 = tex2D_linearize(tex, sample1_uv).rgb; const vec3 sample2 = tex2D_linearize(tex, sample1_uv + dx).rgb; const vec3 sample3 = tex2D_linearize(tex, sample4_uv - dx).rgb; const vec3 sample4 = tex2D_linearize(tex, sample4_uv).rgb; const vec3 sample5 = tex2D_linearize(tex, sample4_uv + dx).rgb; const vec3 sample6 = tex2D_linearize(tex, sample7_uv - dx).rgb; const vec3 sample7 = tex2D_linearize(tex, sample7_uv).rgb; const vec3 sample8 = tex2D_linearize(tex, sample7_uv + dx).rgb; // Statically compute Gaussian sample weights: const float w4 = 1.0; const float w1_3_5_7 = exp(-LENGTH_SQ(vec2(1.0, 0.0)) * denom_inv); const float w0_2_6_8 = exp(-LENGTH_SQ(vec2(1.0, 1.0)) * denom_inv); const float weight_sum_inv = 1.0/(w4 + 4.0 * (w1_3_5_7 + w0_2_6_8)); // Weight and sum the samples: const vec3 sum = w4 * sample4 + w1_3_5_7 * (sample1 + sample3 + sample5 + sample7) + w0_2_6_8 * (sample0 + sample2 + sample6 + sample8); return sum * weight_sum_inv; } // Resizable one-pass blurs: vec3 tex2Dblur3x3resize(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur3x3resize(texture, tex_uv, dxdy, blur3_std_dev); } vec3 tex2Dblur9fast(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Requires: Same as tex2Dblur11() // Returns: A 1D 9x Gaussian blurred texture lookup using 1 nearest // neighbor and 4 linear taps. It may be mipmapped depending // on settings and dxdy. // First get the texel weights and normalization factor as above. const float denom_inv = 0.5/(sigma*sigma); const float w0 = 1.0; const float w1 = exp(-1.0 * denom_inv); const float w2 = exp(-4.0 * denom_inv); const float w3 = exp(-9.0 * denom_inv); const float w4 = exp(-16.0 * denom_inv); const float weight_sum_inv = 1.0 / (w0 + 2.0 * (w1 + w2 + w3 + w4)); // Calculate combined weights and linear sample ratios between texel pairs. const float w12 = w1 + w2; const float w34 = w3 + w4; const float w12_ratio = w2/w12; const float w34_ratio = w4/w34; // Statically normalize weights, sum weighted samples, and return: vec3 sum = vec3(0.0); sum += w34 * tex2D_linearize(tex, tex_uv - (3.0 + w34_ratio) * dxdy).rgb; sum += w12 * tex2D_linearize(tex, tex_uv - (1.0 + w12_ratio) * dxdy).rgb; sum += w0 * tex2D_linearize(tex, tex_uv).rgb; sum += w12 * tex2D_linearize(tex, tex_uv + (1.0 + w12_ratio) * dxdy).rgb; sum += w34 * tex2D_linearize(tex, tex_uv + (3.0 + w34_ratio) * dxdy).rgb; return sum * weight_sum_inv; } vec3 tex2Dblur9x9(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Perform a 1-pass 9x9 blur with 5x5 bilinear samples. // Requires: Same as tex2Dblur9() // Returns: A 9x9 Gaussian blurred mipmapped texture lookup composed of // 5x5 carefully selected bilinear samples. // Description: // Perform a 1-pass 9x9 blur with 5x5 bilinear samples. Adjust the // bilinear sample location to reflect the true Gaussian weights for each // underlying texel. The following diagram illustrates the relative // locations of bilinear samples. Each sample with the same number has the // same weight (notice the symmetry). The letters a, b, c, d distinguish // quadrants, and the letters U, D, L, R, C (up, down, left, right, center) // distinguish 1D directions along the line containing the pixel center: // 6a 5a 2U 5b 6b // 4a 3a 1U 3b 4b // 2L 1L 0C 1R 2R // 4c 3c 1D 3d 4d // 6c 5c 2D 5d 6d // The following diagram illustrates the underlying equally spaced texels, // named after the sample that accesses them and subnamed by their location // within their 2x2, 2x1, 1x2, or 1x1 texel block: // 6a4 6a3 5a4 5a3 2U2 5b3 5b4 6b3 6b4 // 6a2 6a1 5a2 5a1 2U1 5b1 5b2 6b1 6b2 // 4a4 4a3 3a4 3a3 1U2 3b3 3b4 4b3 4b4 // 4a2 4a1 3a2 3a1 1U1 3b1 3b2 4b1 4b2 // 2L2 2L1 1L2 1L1 0C1 1R1 1R2 2R1 2R2 // 4c2 4c1 3c2 3c1 1D1 3d1 3d2 4d1 4d2 // 4c4 4c3 3c4 3c3 1D2 3d3 3d4 4d3 4d4 // 6c2 6c1 5c2 5c1 2D1 5d1 5d2 6d1 6d2 // 6c4 6c3 5c4 5c3 2D2 5d3 5d4 6d3 6d4 // Note there is only one C texel and only two texels for each U, D, L, or // R sample. The center sample is effectively a nearest neighbor sample, // and the U/D/L/R samples use 1D linear filtering. All other texels are // read with bilinear samples somewhere within their 2x2 texel blocks. // COMPUTE TEXTURE COORDS: // Statically compute sampling offsets within each 2x2 texel block, based // on 1D sampling ratios between texels [1, 2] and [3, 4] texels away from // the center, and reuse them independently for both dimensions. Compute // these offsets based on the relative 1D Gaussian weights of the texels // in question. (w1off means "Gaussian weight for the texel 1.0 texels // away from the pixel center," etc.). const float denom_inv = 0.5/(sigma*sigma); const float w1off = exp(-1.0 * denom_inv); const float w2off = exp(-4.0 * denom_inv); const float w3off = exp(-9.0 * denom_inv); const float w4off = exp(-16.0 * denom_inv); const float texel1to2ratio = w2off/(w1off + w2off); const float texel3to4ratio = w4off/(w3off + w4off); // Statically compute texel offsets from the fragment center to each // bilinear sample in the bottom-right quadrant, including x-axis-aligned: const vec2 sample1R_texel_offset = vec2(1.0, 0.0) + vec2(texel1to2ratio, 0.0); const vec2 sample2R_texel_offset = vec2(3.0, 0.0) + vec2(texel3to4ratio, 0.0); const vec2 sample3d_texel_offset = vec2(1.0, 1.0) + vec2(texel1to2ratio, texel1to2ratio); const vec2 sample4d_texel_offset = vec2(3.0, 1.0) + vec2(texel3to4ratio, texel1to2ratio); const vec2 sample5d_texel_offset = vec2(1.0, 3.0) + vec2(texel1to2ratio, texel3to4ratio); const vec2 sample6d_texel_offset = vec2(3.0, 3.0) + vec2(texel3to4ratio, texel3to4ratio); // CALCULATE KERNEL WEIGHTS FOR ALL SAMPLES: // Statically compute Gaussian texel weights for the bottom-right quadrant. // Read underscores as "and." const float w1R1 = w1off; const float w1R2 = w2off; const float w2R1 = w3off; const float w2R2 = w4off; const float w3d1 = exp(-LENGTH_SQ(vec2(1.0, 1.0)) * denom_inv); const float w3d2_3d3 = exp(-LENGTH_SQ(vec2(2.0, 1.0)) * denom_inv); const float w3d4 = exp(-LENGTH_SQ(vec2(2.0, 2.0)) * denom_inv); const float w4d1_5d1 = exp(-LENGTH_SQ(vec2(3.0, 1.0)) * denom_inv); const float w4d2_5d3 = exp(-LENGTH_SQ(vec2(4.0, 1.0)) * denom_inv); const float w4d3_5d2 = exp(-LENGTH_SQ(vec2(3.0, 2.0)) * denom_inv); const float w4d4_5d4 = exp(-LENGTH_SQ(vec2(4.0, 2.0)) * denom_inv); const float w6d1 = exp(-LENGTH_SQ(vec2(3.0, 3.0)) * denom_inv); const float w6d2_6d3 = exp(-LENGTH_SQ(vec2(4.0, 3.0)) * denom_inv); const float w6d4 = exp(-LENGTH_SQ(vec2(4.0, 4.0)) * denom_inv); // Statically add texel weights in each sample to get sample weights: const float w0 = 1.0; const float w1 = w1R1 + w1R2; const float w2 = w2R1 + w2R2; const float w3 = w3d1 + 2.0 * w3d2_3d3 + w3d4; const float w4 = w4d1_5d1 + w4d2_5d3 + w4d3_5d2 + w4d4_5d4; const float w5 = w4; const float w6 = w6d1 + 2.0 * w6d2_6d3 + w6d4; // Get the weight sum inverse (normalization factor): const float weight_sum_inv = 1.0/(w0 + 4.0 * (w1 + w2 + w3 + w4 + w5 + w6)); // LOAD TEXTURE SAMPLES: // Load all 25 samples (1 nearest, 8 linear, 16 bilinear) using symmetry: const vec2 mirror_x = vec2(-1.0, 1.0); const vec2 mirror_y = vec2(1.0, -1.0); const vec2 mirror_xy = vec2(-1.0, -1.0); const vec2 dxdy_mirror_x = dxdy * mirror_x; const vec2 dxdy_mirror_y = dxdy * mirror_y; const vec2 dxdy_mirror_xy = dxdy * mirror_xy; // Sampling order doesn't seem to affect performance, so just be clear: const vec3 sample0C = tex2D_linearize(tex, tex_uv).rgb; const vec3 sample1R = tex2D_linearize(tex, tex_uv + dxdy * sample1R_texel_offset).rgb; const vec3 sample1D = tex2D_linearize(tex, tex_uv + dxdy * sample1R_texel_offset.yx).rgb; const vec3 sample1L = tex2D_linearize(tex, tex_uv - dxdy * sample1R_texel_offset).rgb; const vec3 sample1U = tex2D_linearize(tex, tex_uv - dxdy * sample1R_texel_offset.yx).rgb; const vec3 sample2R = tex2D_linearize(tex, tex_uv + dxdy * sample2R_texel_offset).rgb; const vec3 sample2D = tex2D_linearize(tex, tex_uv + dxdy * sample2R_texel_offset.yx).rgb; const vec3 sample2L = tex2D_linearize(tex, tex_uv - dxdy * sample2R_texel_offset).rgb; const vec3 sample2U = tex2D_linearize(tex, tex_uv - dxdy * sample2R_texel_offset.yx).rgb; const vec3 sample3d = tex2D_linearize(tex, tex_uv + dxdy * sample3d_texel_offset).rgb; const vec3 sample3c = tex2D_linearize(tex, tex_uv + dxdy_mirror_x * sample3d_texel_offset).rgb; const vec3 sample3b = tex2D_linearize(tex, tex_uv + dxdy_mirror_y * sample3d_texel_offset).rgb; const vec3 sample3a = tex2D_linearize(tex, tex_uv + dxdy_mirror_xy * sample3d_texel_offset).rgb; const vec3 sample4d = tex2D_linearize(tex, tex_uv + dxdy * sample4d_texel_offset).rgb; const vec3 sample4c = tex2D_linearize(tex, tex_uv + dxdy_mirror_x * sample4d_texel_offset).rgb; const vec3 sample4b = tex2D_linearize(tex, tex_uv + dxdy_mirror_y * sample4d_texel_offset).rgb; const vec3 sample4a = tex2D_linearize(tex, tex_uv + dxdy_mirror_xy * sample4d_texel_offset).rgb; const vec3 sample5d = tex2D_linearize(tex, tex_uv + dxdy * sample5d_texel_offset).rgb; const vec3 sample5c = tex2D_linearize(tex, tex_uv + dxdy_mirror_x * sample5d_texel_offset).rgb; const vec3 sample5b = tex2D_linearize(tex, tex_uv + dxdy_mirror_y * sample5d_texel_offset).rgb; const vec3 sample5a = tex2D_linearize(tex, tex_uv + dxdy_mirror_xy * sample5d_texel_offset).rgb; const vec3 sample6d = tex2D_linearize(tex, tex_uv + dxdy * sample6d_texel_offset).rgb; const vec3 sample6c = tex2D_linearize(tex, tex_uv + dxdy_mirror_x * sample6d_texel_offset).rgb; const vec3 sample6b = tex2D_linearize(tex, tex_uv + dxdy_mirror_y * sample6d_texel_offset).rgb; const vec3 sample6a = tex2D_linearize(tex, tex_uv + dxdy_mirror_xy * sample6d_texel_offset).rgb; // SUM WEIGHTED SAMPLES: // Statically normalize weights (so total = 1.0), and sum weighted samples. vec3 sum = w0 * sample0C; sum += w1 * (sample1R + sample1D + sample1L + sample1U); sum += w2 * (sample2R + sample2D + sample2L + sample2U); sum += w3 * (sample3d + sample3c + sample3b + sample3a); sum += w4 * (sample4d + sample4c + sample4b + sample4a); sum += w5 * (sample5d + sample5c + sample5b + sample5a); sum += w6 * (sample6d + sample6c + sample6b + sample6a); return sum * weight_sum_inv; } vec3 tex2Dblur7x7(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Perform a 1-pass 7x7 blur with 5x5 bilinear samples. // Requires: Same as tex2Dblur9() // Returns: A 7x7 Gaussian blurred mipmapped texture lookup composed of // 4x4 carefully selected bilinear samples. // Description: // First see the descriptions for tex2Dblur9x9() and tex2Dblur7(). This // blur mixes concepts from both. The sample layout is as follows: // 4a 3a 3b 4b // 2a 1a 1b 2b // 2c 1c 1d 2d // 4c 3c 3d 4d // The texel layout is as follows. Note that samples 3a/3b, 1a/1b, 1c/1d, // and 3c/3d share a vertical column of texels, and samples 2a/2c, 1a/1c, // 1b/1d, and 2b/2d share a horizontal row of texels (all sample1's share // the center texel): // 4a4 4a3 3a4 3ab3 3b4 4b3 4b4 // 4a2 4a1 3a2 3ab1 3b2 4b1 4b2 // 2a4 2a3 1a4 1ab3 1b4 2b3 2b4 // 2ac2 2ac1 1ac2 1* 1bd2 2bd1 2bd2 // 2c4 2c3 1c4 1cd3 1d4 2d3 2d4 // 4c2 4c1 3c2 3cd1 3d2 4d1 4d2 // 4c4 4c3 3c4 3cd3 3d4 4d3 4d4 // COMPUTE TEXTURE COORDS: // Statically compute bilinear sampling offsets (details in tex2Dblur9x9). const float denom_inv = 0.5/(sigma*sigma); const float w0off = 1.0; const float w1off = exp(-1.0 * denom_inv); const float w2off = exp(-4.0 * denom_inv); const float w3off = exp(-9.0 * denom_inv); const float texel0to1ratio = w1off/(w0off * 0.5 + w1off); const float texel2to3ratio = w3off/(w2off + w3off); // Statically compute texel offsets from the fragment center to each // bilinear sample in the bottom-right quadrant, including axis-aligned: const vec2 sample1d_texel_offset = vec2(texel0to1ratio, texel0to1ratio); const vec2 sample2d_texel_offset = vec2(2.0, 0.0) + vec2(texel2to3ratio, texel0to1ratio); const vec2 sample3d_texel_offset = vec2(0.0, 2.0) + vec2(texel0to1ratio, texel2to3ratio); const vec2 sample4d_texel_offset = vec2(2.0, 2.0) + vec2(texel2to3ratio, texel2to3ratio); // CALCULATE KERNEL WEIGHTS FOR ALL SAMPLES: // Statically compute Gaussian texel weights for the bottom-right quadrant. // Read underscores as "and." const float w1abcd = 1.0; const float w1bd2_1cd3 = exp(-LENGTH_SQ(vec2(1.0, 0.0)) * denom_inv); const float w2bd1_3cd1 = exp(-LENGTH_SQ(vec2(2.0, 0.0)) * denom_inv); const float w2bd2_3cd2 = exp(-LENGTH_SQ(vec2(3.0, 0.0)) * denom_inv); const float w1d4 = exp(-LENGTH_SQ(vec2(1.0, 1.0)) * denom_inv); const float w2d3_3d2 = exp(-LENGTH_SQ(vec2(2.0, 1.0)) * denom_inv); const float w2d4_3d4 = exp(-LENGTH_SQ(vec2(3.0, 1.0)) * denom_inv); const float w4d1 = exp(-LENGTH_SQ(vec2(2.0, 2.0)) * denom_inv); const float w4d2_4d3 = exp(-LENGTH_SQ(vec2(3.0, 2.0)) * denom_inv); const float w4d4 = exp(-LENGTH_SQ(vec2(3.0, 3.0)) * denom_inv); // Statically add texel weights in each sample to get sample weights. // Split weights for shared texels between samples sharing them: const float w1 = w1abcd * 0.25 + w1bd2_1cd3 + w1d4; const float w2_3 = (w2bd1_3cd1 + w2bd2_3cd2) * 0.5 + w2d3_3d2 + w2d4_3d4; const float w4 = w4d1 + 2.0 * w4d2_4d3 + w4d4; // Get the weight sum inverse (normalization factor): const float weight_sum_inv = 1.0/(4.0 * (w1 + 2.0 * w2_3 + w4)); // LOAD TEXTURE SAMPLES: // Load all 16 samples using symmetry: const vec2 mirror_x = vec2(-1.0, 1.0); const vec2 mirror_y = vec2(1.0, -1.0); const vec2 mirror_xy = vec2(-1.0, -1.0); const vec2 dxdy_mirror_x = dxdy * mirror_x; const vec2 dxdy_mirror_y = dxdy * mirror_y; const vec2 dxdy_mirror_xy = dxdy * mirror_xy; const vec3 sample1a = tex2D_linearize(tex, tex_uv + dxdy_mirror_xy * sample1d_texel_offset).rgb; const vec3 sample2a = tex2D_linearize(tex, tex_uv + dxdy_mirror_xy * sample2d_texel_offset).rgb; const vec3 sample3a = tex2D_linearize(tex, tex_uv + dxdy_mirror_xy * sample3d_texel_offset).rgb; const vec3 sample4a = tex2D_linearize(tex, tex_uv + dxdy_mirror_xy * sample4d_texel_offset).rgb; const vec3 sample1b = tex2D_linearize(tex, tex_uv + dxdy_mirror_y * sample1d_texel_offset).rgb; const vec3 sample2b = tex2D_linearize(tex, tex_uv + dxdy_mirror_y * sample2d_texel_offset).rgb; const vec3 sample3b = tex2D_linearize(tex, tex_uv + dxdy_mirror_y * sample3d_texel_offset).rgb; const vec3 sample4b = tex2D_linearize(tex, tex_uv + dxdy_mirror_y * sample4d_texel_offset).rgb; const vec3 sample1c = tex2D_linearize(tex, tex_uv + dxdy_mirror_x * sample1d_texel_offset).rgb; const vec3 sample2c = tex2D_linearize(tex, tex_uv + dxdy_mirror_x * sample2d_texel_offset).rgb; const vec3 sample3c = tex2D_linearize(tex, tex_uv + dxdy_mirror_x * sample3d_texel_offset).rgb; const vec3 sample4c = tex2D_linearize(tex, tex_uv + dxdy_mirror_x * sample4d_texel_offset).rgb; const vec3 sample1d = tex2D_linearize(tex, tex_uv + dxdy * sample1d_texel_offset).rgb; const vec3 sample2d = tex2D_linearize(tex, tex_uv + dxdy * sample2d_texel_offset).rgb; const vec3 sample3d = tex2D_linearize(tex, tex_uv + dxdy * sample3d_texel_offset).rgb; const vec3 sample4d = tex2D_linearize(tex, tex_uv + dxdy * sample4d_texel_offset).rgb; // SUM WEIGHTED SAMPLES: // Statically normalize weights (so total = 1.0), and sum weighted samples. vec3 sum = vec3(0.0); sum += w1 * (sample1a + sample1b + sample1c + sample1d); sum += w2_3 * (sample2a + sample2b + sample2c + sample2d); sum += w2_3 * (sample3a + sample3b + sample3c + sample3d); sum += w4 * (sample4a + sample4b + sample4c + sample4d); return sum * weight_sum_inv; } vec3 tex2Dblur5x5(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Perform a 1-pass 5x5 blur with 3x3 bilinear samples. // Requires: Same as tex2Dblur9() // Returns: A 5x5 Gaussian blurred mipmapped texture lookup composed of // 3x3 carefully selected bilinear samples. // Description: // First see the description for tex2Dblur9x9(). This blur uses the same // concept and sample/texel locations except on a smaller scale. Samples: // 2a 1U 2b // 1L 0C 1R // 2c 1D 2d // Texels: // 2a4 2a3 1U2 2b3 2b4 // 2a2 2a1 1U1 2b1 2b2 // 1L2 1L1 0C1 1R1 1R2 // 2c2 2c1 1D1 2d1 2d2 // 2c4 2c3 1D2 2d3 2d4 // COMPUTE TEXTURE COORDS: // Statically compute bilinear sampling offsets (details in tex2Dblur9x9). const float denom_inv = 0.5/(sigma*sigma); const float w1off = exp(-1.0 * denom_inv); const float w2off = exp(-4.0 * denom_inv); const float texel1to2ratio = w2off/(w1off + w2off); // Statically compute texel offsets from the fragment center to each // bilinear sample in the bottom-right quadrant, including x-axis-aligned: const vec2 sample1R_texel_offset = vec2(1.0, 0.0) + vec2(texel1to2ratio, 0.0); const vec2 sample2d_texel_offset = vec2(1.0, 1.0) + vec2(texel1to2ratio, texel1to2ratio); // CALCULATE KERNEL WEIGHTS FOR ALL SAMPLES: // Statically compute Gaussian texel weights for the bottom-right quadrant. // Read underscores as "and." const float w1R1 = w1off; const float w1R2 = w2off; const float w2d1 = exp(-LENGTH_SQ(vec2(1.0, 1.0)) * denom_inv); const float w2d2_3 = exp(-LENGTH_SQ(vec2(2.0, 1.0)) * denom_inv); const float w2d4 = exp(-LENGTH_SQ(vec2(2.0, 2.0)) * denom_inv); // Statically add texel weights in each sample to get sample weights: const float w0 = 1.0; const float w1 = w1R1 + w1R2; const float w2 = w2d1 + 2.0 * w2d2_3 + w2d4; // Get the weight sum inverse (normalization factor): const float weight_sum_inv = 1.0/(w0 + 4.0 * (w1 + w2)); // LOAD TEXTURE SAMPLES: // Load all 9 samples (1 nearest, 4 linear, 4 bilinear) using symmetry: const vec2 mirror_x = vec2(-1.0, 1.0); const vec2 mirror_y = vec2(1.0, -1.0); const vec2 mirror_xy = vec2(-1.0, -1.0); const vec2 dxdy_mirror_x = dxdy * mirror_x; const vec2 dxdy_mirror_y = dxdy * mirror_y; const vec2 dxdy_mirror_xy = dxdy * mirror_xy; const vec3 sample0C = tex2D_linearize(tex, tex_uv).rgb; const vec3 sample1R = tex2D_linearize(tex, tex_uv + dxdy * sample1R_texel_offset).rgb; const vec3 sample1D = tex2D_linearize(tex, tex_uv + dxdy * sample1R_texel_offset.yx).rgb; const vec3 sample1L = tex2D_linearize(tex, tex_uv - dxdy * sample1R_texel_offset).rgb; const vec3 sample1U = tex2D_linearize(tex, tex_uv - dxdy * sample1R_texel_offset.yx).rgb; const vec3 sample2d = tex2D_linearize(tex, tex_uv + dxdy * sample2d_texel_offset).rgb; const vec3 sample2c = tex2D_linearize(tex, tex_uv + dxdy_mirror_x * sample2d_texel_offset).rgb; const vec3 sample2b = tex2D_linearize(tex, tex_uv + dxdy_mirror_y * sample2d_texel_offset).rgb; const vec3 sample2a = tex2D_linearize(tex, tex_uv + dxdy_mirror_xy * sample2d_texel_offset).rgb; // SUM WEIGHTED SAMPLES: // Statically normalize weights (so total = 1.0), and sum weighted samples. vec3 sum = w0 * sample0C; sum += w1 * (sample1R + sample1D + sample1L + sample1U); sum += w2 * (sample2a + sample2b + sample2c + sample2d); return sum * weight_sum_inv; } vec3 tex2Dblur3x3(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy, const float sigma) { // Perform a 1-pass 3x3 blur with 5x5 bilinear samples. // Requires: Same as tex2Dblur9() // Returns: A 3x3 Gaussian blurred mipmapped texture lookup composed of // 2x2 carefully selected bilinear samples. // Description: // First see the descriptions for tex2Dblur9x9() and tex2Dblur7(). This // blur mixes concepts from both. The sample layout is as follows: // 0a 0b // 0c 0d // The texel layout is as follows. Note that samples 0a/0b and 0c/0d share // a vertical column of texels, and samples 0a/0c and 0b/0d share a // horizontal row of texels (all samples share the center texel): // 0a3 0ab2 0b3 // 0ac1 0*0 0bd1 // 0c3 0cd2 0d3 // COMPUTE TEXTURE COORDS: // Statically compute bilinear sampling offsets (details in tex2Dblur9x9). const float denom_inv = 0.5/(sigma*sigma); const float w0off = 1.0; const float w1off = exp(-1.0 * denom_inv); const float texel0to1ratio = w1off/(w0off * 0.5 + w1off); // Statically compute texel offsets from the fragment center to each // bilinear sample in the bottom-right quadrant, including axis-aligned: const vec2 sample0d_texel_offset = vec2(texel0to1ratio, texel0to1ratio); // LOAD TEXTURE SAMPLES: // Load all 4 samples using symmetry: const vec2 mirror_x = vec2(-1.0, 1.0); const vec2 mirror_y = vec2(1.0, -1.0); const vec2 mirror_xy = vec2(-1.0, -1.0); const vec2 dxdy_mirror_x = dxdy * mirror_x; const vec2 dxdy_mirror_y = dxdy * mirror_y; const vec2 dxdy_mirror_xy = dxdy * mirror_xy; const vec3 sample0a = tex2D_linearize(tex, tex_uv + dxdy_mirror_xy * sample0d_texel_offset).rgb; const vec3 sample0b = tex2D_linearize(tex, tex_uv + dxdy_mirror_y * sample0d_texel_offset).rgb; const vec3 sample0c = tex2D_linearize(tex, tex_uv + dxdy_mirror_x * sample0d_texel_offset).rgb; const vec3 sample0d = tex2D_linearize(tex, tex_uv + dxdy * sample0d_texel_offset).rgb; // SUM WEIGHTED SAMPLES: // Weights for all samples are the same, so just average them: return 0.25 * (sample0a + sample0b + sample0c + sample0d); } vec3 tex2Dblur9fast(const sampler2D tex, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur9fast(tex, tex_uv, dxdy, blur9_std_dev); } vec3 tex2Dblur17fast(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur17fast(texture, tex_uv, dxdy, blur17_std_dev); } vec3 tex2Dblur25fast(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur25fast(texture, tex_uv, dxdy, blur25_std_dev); } vec3 tex2Dblur43fast(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur43fast(texture, tex_uv, dxdy, blur43_std_dev); } vec3 tex2Dblur31fast(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur31fast(texture, tex_uv, dxdy, blur31_std_dev); } vec3 tex2Dblur3fast(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur3fast(texture, tex_uv, dxdy, blur3_std_dev); } vec3 tex2Dblur3x3(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur3x3(texture, tex_uv, dxdy, blur3_std_dev); } vec3 tex2Dblur5fast(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur5fast(texture, tex_uv, dxdy, blur5_std_dev); } vec3 tex2Dblur5resize(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur5resize(texture, tex_uv, dxdy, blur5_std_dev); } vec3 tex2Dblur3resize(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur3resize(texture, tex_uv, dxdy, blur3_std_dev); } vec3 tex2Dblur5x5(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur5x5(texture, tex_uv, dxdy, blur5_std_dev); } vec3 tex2Dblur7resize(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur7resize(texture, tex_uv, dxdy, blur7_std_dev); } vec3 tex2Dblur7fast(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur7fast(texture, tex_uv, dxdy, blur7_std_dev); } vec3 tex2Dblur7x7(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur7x7(texture, tex_uv, dxdy, blur7_std_dev); } vec3 tex2Dblur9resize(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur9resize(texture, tex_uv, dxdy, blur9_std_dev); } vec3 tex2Dblur9x9(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur9x9(texture, tex_uv, dxdy, blur9_std_dev); } vec3 tex2Dblur11resize(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur11resize(texture, tex_uv, dxdy, blur11_std_dev); } vec3 tex2Dblur11fast(const sampler2D texture, const vec2 tex_uv, const vec2 dxdy) { return tex2Dblur11fast(texture, tex_uv, dxdy, blur11_std_dev); } #endif // BLUR_FUNCTIONS_H