/** * @file class2\wl\cloudsV.glsl * * $LicenseInfo:firstyear=2005&license=viewerlgpl$ * Second Life Viewer Source Code * Copyright (C) 2005, 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 mat4 modelview_projection_matrix; ATTRIBUTE vec3 position; ATTRIBUTE vec2 texcoord0; ////////////////////////////////////////////////////////////////////////// // The vertex shader for creating the atmospheric sky /////////////////////////////////////////////////////////////////////////////// // Output parameters VARYING vec3 vary_CloudColorSun; VARYING vec3 vary_CloudColorAmbient; VARYING float vary_CloudDensity; VARYING vec2 vary_texcoord0; VARYING vec2 vary_texcoord1; VARYING vec2 vary_texcoord2; VARYING vec2 vary_texcoord3; VARYING float altitude_blend_factor; // Inputs uniform vec3 camPosLocal; uniform vec3 lightnorm; uniform vec3 sunlight_color; uniform vec3 moonlight_color; uniform int sun_up_factor; uniform vec3 ambient_color; uniform vec3 blue_horizon; uniform vec3 blue_density; uniform float haze_horizon; uniform float haze_density; uniform float cloud_shadow; uniform float density_multiplier; uniform float max_y; uniform vec3 glow; uniform float sun_moon_glow_factor; uniform vec3 cloud_color; uniform float cloud_scale; // NOTE: Keep these in sync! // indra\newview\app_settings\shaders\class1\deferred\skyV.glsl // indra\newview\app_settings\shaders\class1\deferred\cloudsV.glsl // indra\newview\app-settings\shaders\class2\windlight\cloudsV.glsl // indra\newview\lllegacyatmospherics.cpp // indra\newview\llsettingsvo.cpp void main() { // World / view / projection gl_Position = modelview_projection_matrix * vec4(position.xyz, 1.0); // Texture coords // SL-13084 EEP added support for custom cloud textures -- flip them horizontally to match the preview of Clouds > Cloud Scroll vary_texcoord0 = vec2(-texcoord0.x, texcoord0.y); // See: LLSettingsVOSky::applySpecial vary_texcoord0.xy -= 0.5; vary_texcoord0.xy /= cloud_scale; vary_texcoord0.xy += 0.5; vary_texcoord1 = vary_texcoord0; vary_texcoord1.x += lightnorm.x * 0.0125; vary_texcoord1.y += lightnorm.z * 0.0125; vary_texcoord2 = vary_texcoord0 * 16.; vary_texcoord3 = vary_texcoord1 * 16.; // Get relative position vec3 rel_pos = position.xyz - camPosLocal.xyz + vec3(0, 50, 0); // fade clouds beyond a certain point so the bottom of the sky dome doesn't look silly at high altitude altitude_blend_factor = clamp((rel_pos.y + 512.0) / max_y, 0.0, 1.0); // Adj position vector to clamp altitude if (rel_pos.y > 0.) { rel_pos *= (max_y / rel_pos.y); } if (rel_pos.y < 0.) { rel_pos *= (-32000. / rel_pos.y); } // Can normalize then vec3 rel_pos_norm = normalize(rel_pos); float rel_pos_len = length(rel_pos); // Initialize temp variables vec3 sunlight = sunlight_color; vec3 light_atten; // Sunlight attenuation effect (hue and brightness) due to atmosphere // this is used later for sunlight modulation at various altitudes light_atten = (blue_density + vec3(haze_density * 0.25)) * (density_multiplier * max_y); // Calculate relative weights vec3 combined_haze = abs(blue_density) + vec3(abs(haze_density)); vec3 blue_weight = blue_density / combined_haze; vec3 haze_weight = haze_density / combined_haze; // Compute sunlight from rel_pos & lightnorm (for long rays like sky) float off_axis = 1.0 / max(1e-6, max(0., rel_pos_norm.y) + lightnorm.y); sunlight *= exp(-light_atten * off_axis); // Distance float density_dist = rel_pos_len * density_multiplier; // Transparency (-> combined_haze) // ATI Bugfix -- can't store combined_haze*density_dist in a variable because the ati // compiler gets confused. combined_haze = exp(-combined_haze * density_dist); // Compute haze glow float haze_glow = 1.0 - dot(rel_pos_norm, lightnorm.xyz); // 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 haze_glow *= sun_moon_glow_factor; // Add "minimum anti-solar illumination" // For sun, add to glow. For moon, remove glow entirely. SL-13768 haze_glow = (sun_moon_glow_factor < 1.0) ? 0.0 : (haze_glow + 0.25); // Increase ambient when there are more clouds vec3 tmpAmbient = ambient_color; tmpAmbient += (1. - tmpAmbient) * cloud_shadow * 0.5; // Dim sunlight by cloud shadow percentage sunlight *= (1. - cloud_shadow); // Haze color below cloud vec3 additiveColorBelowCloud = (blue_horizon * blue_weight * (sunlight + tmpAmbient) + (haze_horizon * haze_weight) * (sunlight * haze_glow + tmpAmbient)); // CLOUDS sunlight = sunlight_color; // SL-14707 reset color -- Clouds are unusually dim in EEP off_axis = 1.0 / max(1e-6, lightnorm.y * 2.); sunlight *= exp(-light_atten * off_axis); // Cloud color out vary_CloudColorSun = (sunlight * haze_glow) * cloud_color; vary_CloudColorAmbient = tmpAmbient * cloud_color; // Attenuate cloud color by atmosphere combined_haze = sqrt(combined_haze); // less atmos opacity (more transparency) below clouds vary_CloudColorSun *= combined_haze; vary_CloudColorAmbient *= combined_haze; vec3 oHazeColorBelowCloud = additiveColorBelowCloud * (1. - combined_haze); // Make a nice cloud density based on the cloud_shadow value that was passed in. vary_CloudDensity = 2. * (cloud_shadow - 0.25); // Combine these to minimize register use vary_CloudColorAmbient += oHazeColorBelowCloud; // needs this to compile on mac //vary_AtmosAttenuation = vec3(0.0,0.0,0.0); // END CLOUDS }