From aaf7b17db047f0cb2630b479d5468062e6ca815e Mon Sep 17 00:00:00 2001 From: Dave Parks Date: Tue, 27 Sep 2022 23:32:02 -0500 Subject: SL-18190 WIP -- Take 2 on linear space windlight (more methodical approach -- make desired interface but brute force color conversions). Placeholder PBR water and move to deprecate forward rendering shaders. --- .../class2/windlight/atmosphericsFuncs.glsl | 148 +++++++++++++++++++++ 1 file changed, 148 insertions(+) create mode 100644 indra/newview/app_settings/shaders/class2/windlight/atmosphericsFuncs.glsl (limited to 'indra/newview/app_settings/shaders/class2/windlight/atmosphericsFuncs.glsl') diff --git a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsFuncs.glsl b/indra/newview/app_settings/shaders/class2/windlight/atmosphericsFuncs.glsl new file mode 100644 index 0000000000..e7e1938a11 --- /dev/null +++ b/indra/newview/app_settings/shaders/class2/windlight/atmosphericsFuncs.glsl @@ -0,0 +1,148 @@ +/** + * @file class2\windlight\atmosphericsFuncs.glsl + * + * $LicenseInfo:firstyear=2022&license=viewerlgpl$ + * Second Life Viewer Source Code + * Copyright (C) 2022, Linden Research, Inc. + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; + * version 2.1 of the License only. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + * + * Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA + * $/LicenseInfo$ + */ +uniform vec4 lightnorm; +uniform vec4 sunlight_color; +uniform vec4 moonlight_color; +uniform int sun_up_factor; +uniform vec4 ambient_color; +uniform vec4 blue_horizon; +uniform vec4 blue_density; +uniform float haze_horizon; +uniform float haze_density; +uniform float cloud_shadow; +uniform float density_multiplier; +uniform float distance_multiplier; +uniform float max_y; +uniform vec4 glow; +uniform float scene_light_strength; +uniform mat3 ssao_effect_mat; +uniform int no_atmo; +uniform float sun_moon_glow_factor; + +vec3 srgb_to_linear(vec3 col); + +float getAmbientClamp() { return 1.0f; } + +// return colors in sRGB space +void calcAtmosphericVars(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, + out vec3 atten, bool use_ao) +{ + vec3 rel_pos = inPositionEye; + + //(TERRAIN) limit altitude + if (abs(rel_pos.y) > max_y) rel_pos *= (max_y / rel_pos.y); + + vec3 rel_pos_norm = normalize(rel_pos); + float rel_pos_len = length(rel_pos); + vec4 sunlight = (sun_up_factor == 1) ? sunlight_color : moonlight_color; + + // sunlight attenuation effect (hue and brightness) due to atmosphere + // this is used later for sunlight modulation at various altitudes + vec4 light_atten = (blue_density + vec4(haze_density * 0.25)) * (density_multiplier * max_y); + // I had thought blue_density and haze_density should have equal weighting, + // but attenuation due to haze_density tends to seem too strong + + vec4 combined_haze = blue_density + vec4(haze_density); + vec4 blue_weight = blue_density / combined_haze; + vec4 haze_weight = vec4(haze_density) / combined_haze; + + //(TERRAIN) compute sunlight from lightnorm y component. Factor is roughly cosecant(sun elevation) (for short rays like terrain) + float above_horizon_factor = 1.0 / max(1e-6, lightnorm.y); + sunlight *= exp(-light_atten * above_horizon_factor); // for sun [horizon..overhead] this maps to an exp curve [0..1] + + // main atmospheric scattering line integral + float density_dist = rel_pos_len * density_multiplier; + + // Transparency (-> combined_haze) + // ATI Bugfix -- can't store combined_haze*density_dist*distance_multiplier in a variable because the ati + // compiler gets confused. + combined_haze = exp(-combined_haze * density_dist * distance_multiplier); + + // final atmosphere attenuation factor + atten = combined_haze.rgb; + + // compute haze glow + float haze_glow = dot(rel_pos_norm, lightnorm.xyz); + + // dampen sun additive contrib when not facing it... + // SL-13539: This "if" clause causes an "additive" white artifact at roughly 77 degreees. + // if (length(light_dir) > 0.01) + haze_glow *= max(0.0f, dot(light_dir, rel_pos_norm)); + + haze_glow = 1. - haze_glow; + // haze_glow is 0 at the sun and increases away from sun + haze_glow = max(haze_glow, .001); // set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot) + haze_glow *= glow.x; + // higher glow.x gives dimmer glow (because next step is 1 / "angle") + haze_glow = pow(haze_glow, glow.z); + // glow.z should be negative, so we're doing a sort of (1 / "angle") function + + // add "minimum anti-solar illumination" + haze_glow += .25; + + haze_glow *= sun_moon_glow_factor; + + vec4 amb_color = ambient_color; + + // increase ambient when there are more clouds + vec4 tmpAmbient = amb_color + (vec4(1.) - amb_color) * cloud_shadow * 0.5; + + /* decrease value and saturation (that in HSV, not HSL) for occluded areas + * // for HSV color/geometry used here, see http://gimp-savvy.com/BOOK/index.html?node52.html + * // The following line of code performs the equivalent of: + * float ambAlpha = tmpAmbient.a; + * float ambValue = dot(vec3(tmpAmbient), vec3(0.577)); // projection onto <1/rt(3), 1/rt(3), 1/rt(3)>, the neutral white-black axis + * vec3 ambHueSat = vec3(tmpAmbient) - vec3(ambValue); + * tmpAmbient = vec4(RenderSSAOEffect.valueFactor * vec3(ambValue) + RenderSSAOEffect.saturationFactor *(1.0 - ambFactor) * ambHueSat, + * ambAlpha); + */ + if (use_ao) + { + tmpAmbient = vec4(mix(ssao_effect_mat * tmpAmbient.rgb, tmpAmbient.rgb, ambFactor), tmpAmbient.a); + } + + // Similar/Shared Algorithms: + // indra\llinventory\llsettingssky.cpp -- LLSettingsSky::calculateLightSettings() + // indra\newview\app_settings\shaders\class1\windlight\atmosphericsFuncs.glsl -- calcAtmosphericVars() + // haze color + vec3 cs = sunlight.rgb * (1. - cloud_shadow); + additive = (blue_horizon.rgb * blue_weight.rgb) * (cs + tmpAmbient.rgb) + (haze_horizon * haze_weight.rgb) * (cs * haze_glow + tmpAmbient.rgb); + + // brightness of surface both sunlight and ambient + sunlit = sunlight.rgb; + amblit = tmpAmbient.rgb; + additive *= vec3(1.0 - combined_haze); +} + +// return colors in linear space +void calcAtmosphericVarsLinear(vec3 inPositionEye, vec3 light_dir, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, + out vec3 atten, bool use_ao) +{ + calcAtmosphericVars(inPositionEye, light_dir, ambFactor, sunlit, amblit, additive, atten, use_ao); + sunlit = srgb_to_linear(sunlit)*2.25; + amblit = srgb_to_linear(amblit)*0.15; + additive = srgb_to_linear(additive); + atten = srgb_to_linear(atten); +} -- cgit v1.2.3