/indra/newview/app_settings/shaders/class1/deferred/sunLightSSAOF.glsl
https://bitbucket.org/lindenlab/viewer-beta/ · GLSL · 135 lines · 72 code · 29 blank · 34 comment · 2 complexity · 22e81bf6235dc37a18fb04776f80f230 MD5 · raw file
- /**
- * @file sunLightSSAOF.glsl
- * $LicenseInfo:firstyear=2007&license=viewerlgpl$
- * Second Life Viewer Source Code
- * Copyright (C) 2007, 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
- * $/LicenseInfo$
- */
-
- #extension GL_ARB_texture_rectangle : enable
- #ifdef DEFINE_GL_FRAGCOLOR
- out vec4 gl_FragColor;
- #endif
- //class 1 -- no shadow, SSAO only
- uniform sampler2DRect depthMap;
- uniform sampler2DRect normalMap;
- uniform sampler2D noiseMap;
- // Inputs
- uniform mat4 shadow_matrix[6];
- uniform vec4 shadow_clip;
- uniform float ssao_radius;
- uniform float ssao_max_radius;
- uniform float ssao_factor;
- uniform float ssao_factor_inv;
- VARYING vec2 vary_fragcoord;
- uniform mat4 inv_proj;
- uniform vec2 screen_res;
- uniform float shadow_bias;
- uniform float shadow_offset;
- vec4 getPosition(vec2 pos_screen)
- {
- float depth = texture2DRect(depthMap, pos_screen.xy).r;
- vec2 sc = pos_screen.xy*2.0;
- sc /= screen_res;
- sc -= vec2(1.0,1.0);
- vec4 ndc = vec4(sc.x, sc.y, 2.0*depth-1.0, 1.0);
- vec4 pos = inv_proj * ndc;
- pos /= pos.w;
- pos.w = 1.0;
- return pos;
- }
- //calculate decreases in ambient lighting when crowded out (SSAO)
- float calcAmbientOcclusion(vec4 pos, vec3 norm)
- {
- float ret = 1.0;
-
- vec2 kern[8];
- // exponentially (^2) distant occlusion samples spread around origin
- kern[0] = vec2(-1.0, 0.0) * 0.125*0.125;
- kern[1] = vec2(1.0, 0.0) * 0.250*0.250;
- kern[2] = vec2(0.0, 1.0) * 0.375*0.375;
- kern[3] = vec2(0.0, -1.0) * 0.500*0.500;
- kern[4] = vec2(0.7071, 0.7071) * 0.625*0.625;
- kern[5] = vec2(-0.7071, -0.7071) * 0.750*0.750;
- kern[6] = vec2(-0.7071, 0.7071) * 0.875*0.875;
- kern[7] = vec2(0.7071, -0.7071) * 1.000*1.000;
- vec2 pos_screen = vary_fragcoord.xy;
- vec3 pos_world = pos.xyz;
- vec2 noise_reflect = texture2D(noiseMap, vary_fragcoord.xy/128.0).xy;
-
- float angle_hidden = 0.0;
- int points = 0;
-
- float scale = min(ssao_radius / -pos_world.z, ssao_max_radius);
-
- // it was found that keeping # of samples a constant was the fastest, probably due to compiler optimizations unrolling?)
- for (int i = 0; i < 8; i++)
- {
- vec2 samppos_screen = pos_screen + scale * reflect(kern[i], noise_reflect);
- vec3 samppos_world = getPosition(samppos_screen).xyz;
-
- vec3 diff = pos_world - samppos_world;
- float dist2 = dot(diff, diff);
-
- // assume each sample corresponds to an occluding sphere with constant radius, constant x-sectional area
- // --> solid angle shrinking by the square of distance
- //radius is somewhat arbitrary, can approx with just some constant k * 1 / dist^2
- //(k should vary inversely with # of samples, but this is taken care of later)
-
- angle_hidden = angle_hidden + float(dot((samppos_world - 0.05*norm - pos_world), norm) > 0.0) * min(1.0/dist2, ssao_factor_inv);
-
- // 'blocked' samples (significantly closer to camera relative to pos_world) are "no data", not "no occlusion"
- points = points + int(diff.z > -1.0);
- }
-
- angle_hidden = min(ssao_factor*angle_hidden/float(points), 1.0);
-
- ret = (1.0 - (float(points != 0) * angle_hidden));
-
- return min(ret, 1.0);
- }
- void main()
- {
- vec2 pos_screen = vary_fragcoord.xy;
-
- //try doing an unproject here
-
- vec4 pos = getPosition(pos_screen);
-
- vec3 norm = texture2DRect(normalMap, pos_screen).xyz;
- norm = vec3((norm.xy-0.5)*2.0,norm.z); // unpack norm
-
- gl_FragColor[0] = 1.0;
- gl_FragColor[1] = calcAmbientOcclusion(pos, norm);
- gl_FragColor[2] = 1.0;
- gl_FragColor[3] = 1.0;
- }