phoenix-firestorm/indra/newview/app_settings/shaders/class1/deferred/shadowUtil.glsl

243 lines
7.3 KiB
GLSL

/**
* @file class1/deferred/shadowUtil.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
* $/LicenseInfo$
*/
uniform sampler2D normalMap;
#if defined(SUN_SHADOW)
uniform sampler2DShadow shadowMap0;
uniform sampler2DShadow shadowMap1;
uniform sampler2DShadow shadowMap2;
uniform sampler2DShadow shadowMap3;
#endif
#if defined(SPOT_SHADOW)
uniform sampler2DShadow shadowMap4;
uniform sampler2DShadow shadowMap5;
#endif
uniform vec3 sun_dir;
uniform vec3 moon_dir;
uniform vec2 shadow_res;
uniform vec2 proj_shadow_res;
uniform mat4 shadow_matrix[6];
uniform vec4 shadow_clip;
uniform float shadow_bias;
uniform float shadow_offset;
uniform float spot_shadow_bias;
uniform float spot_shadow_offset;
uniform mat4 inv_proj;
uniform vec2 screen_res;
uniform int sun_up_factor;
float pcfShadow(sampler2DShadow shadowMap, vec3 norm, vec4 stc, float bias_mul, vec2 pos_screen, vec3 light_dir)
{
#if defined(SUN_SHADOW)
float offset = shadow_bias * bias_mul;
stc.xyz /= stc.w;
stc.z += offset * 2.0;
stc.x = floor(stc.x*shadow_res.x + fract(pos_screen.y*shadow_res.y))/shadow_res.x; // add some chaotic jitter to X sample pos according to Y to disguise the snapping going on here
float cs = texture(shadowMap, stc.xyz);
float shadow = cs * 4.0;
shadow += texture(shadowMap, stc.xyz+vec3( 1.5/shadow_res.x, 0.5/shadow_res.y, 0.0));
shadow += texture(shadowMap, stc.xyz+vec3( 0.5/shadow_res.x, -1.5/shadow_res.y, 0.0));
shadow += texture(shadowMap, stc.xyz+vec3(-1.5/shadow_res.x, -0.5/shadow_res.y, 0.0));
shadow += texture(shadowMap, stc.xyz+vec3(-0.5/shadow_res.x, 1.5/shadow_res.y, 0.0));
return clamp(shadow * 0.125, 0.0, 1.0);
#else
return 1.0;
#endif
}
float pcfSpotShadow(sampler2DShadow shadowMap, vec4 stc, float bias_scale, vec2 pos_screen)
{
#if defined(SPOT_SHADOW)
stc.xyz /= stc.w;
stc.z += spot_shadow_bias * bias_scale;
stc.x = floor(proj_shadow_res.x * stc.x + fract(pos_screen.y*0.666666666)) / proj_shadow_res.x; // snap
float cs = texture(shadowMap, stc.xyz);
float shadow = cs;
vec2 off = 1.0/proj_shadow_res;
off.y *= 1.5;
shadow += texture(shadowMap, stc.xyz+vec3(off.x*2.0, off.y, 0.0));
shadow += texture(shadowMap, stc.xyz+vec3(off.x, -off.y, 0.0));
shadow += texture(shadowMap, stc.xyz+vec3(-off.x, off.y, 0.0));
shadow += texture(shadowMap, stc.xyz+vec3(-off.x*2.0, -off.y, 0.0));
return shadow*0.2;
#else
return 1.0;
#endif
}
float sampleDirectionalShadow(vec3 pos, vec3 norm, vec2 pos_screen)
{
#if defined(SUN_SHADOW)
float shadow = 0.0f;
vec3 light_dir = normalize((sun_up_factor == 1) ? sun_dir : moon_dir);
float dp_directional_light = max(0.0, dot(norm.xyz, light_dir));
dp_directional_light = clamp(dp_directional_light, 0.0, 1.0);
vec3 shadow_pos = pos.xyz;
vec3 offset = light_dir.xyz * (1.0 - dp_directional_light);
shadow_pos += offset * shadow_offset * 2.0;
vec4 spos = vec4(shadow_pos.xyz, 1.0);
if (spos.z > -shadow_clip.w)
{
vec4 lpos;
vec4 near_split = shadow_clip*-0.75;
vec4 far_split = shadow_clip*-1.25;
vec4 transition_domain = near_split-far_split;
float weight = 0.0;
if (spos.z < near_split.z)
{
lpos = shadow_matrix[3]*spos;
float w = 1.0;
w -= max(spos.z-far_split.z, 0.0)/transition_domain.z;
//w = clamp(w, 0.0, 1.0);
float contrib = pcfShadow(shadowMap3, norm, lpos, 1.0, pos_screen, light_dir)*w;
//if (contrib > 0)
{
shadow += contrib;
weight += w;
}
shadow += max((pos.z+shadow_clip.z)/(shadow_clip.z-shadow_clip.w)*2.0-1.0, 0.0);
}
if (spos.z < near_split.y && spos.z > far_split.z)
{
lpos = shadow_matrix[2]*spos;
float w = 1.0;
w -= max(spos.z-far_split.y, 0.0)/transition_domain.y;
w -= max(near_split.z-spos.z, 0.0)/transition_domain.z;
//w = clamp(w, 0.0, 1.0);
float contrib = pcfShadow(shadowMap2, norm, lpos, 1.0, pos_screen, light_dir)*w;
//if (contrib > 0)
{
shadow += contrib;
weight += w;
}
}
if (spos.z < near_split.x && spos.z > far_split.y)
{
lpos = shadow_matrix[1]*spos;
float w = 1.0;
w -= max(spos.z-far_split.x, 0.0)/transition_domain.x;
w -= max(near_split.y-spos.z, 0.0)/transition_domain.y;
//w = clamp(w, 0.0, 1.0);
float contrib = pcfShadow(shadowMap1, norm, lpos, 1.0, pos_screen, light_dir)*w;
//if (contrib > 0)
{
shadow += contrib;
weight += w;
}
}
if (spos.z > far_split.x)
{
lpos = shadow_matrix[0]*spos;
float w = 1.0;
w -= max(near_split.x-spos.z, 0.0)/transition_domain.x;
//w = clamp(w, 0.0, 1.0);
float contrib = pcfShadow(shadowMap0, norm, lpos, 1.0, pos_screen, light_dir)*w;
//if (contrib > 0)
{
shadow += contrib;
weight += w;
}
}
shadow /= weight;
}
else
{
return 1.0f; // lit beyond the far split...
}
//shadow = min(dp_directional_light,shadow);
return shadow;
#else
return 1.0;
#endif
}
float sampleSpotShadow(vec3 pos, vec3 norm, int index, vec2 pos_screen)
{
#if defined(SPOT_SHADOW)
float shadow = 0.0f;
pos += norm * spot_shadow_offset;
vec4 spos = vec4(pos,1.0);
if (spos.z > -shadow_clip.w)
{
vec4 lpos;
vec4 near_split = shadow_clip*-0.75;
vec4 far_split = shadow_clip*-1.25;
vec4 transition_domain = near_split-far_split;
float weight = 0.0;
{
float w = 1.0;
w -= max(spos.z-far_split.z, 0.0)/transition_domain.z;
if (index == 0)
{
lpos = shadow_matrix[4]*spos;
shadow += pcfSpotShadow(shadowMap4, lpos, 0.8, spos.xy)*w;
}
else
{
lpos = shadow_matrix[5]*spos;
shadow += pcfSpotShadow(shadowMap5, lpos, 0.8, spos.xy)*w;
}
weight += w;
shadow += max((pos.z+shadow_clip.z)/(shadow_clip.z-shadow_clip.w)*2.0-1.0, 0.0);
}
shadow /= weight;
}
else
{
shadow = 1.0f;
}
return shadow;
#else
return 1.0;
#endif
}