bgfx/examples/16-shadowmaps/common.sh

236 lines
7.9 KiB
Bash

/*
* Copyright 2013-2014 Dario Manesku. All rights reserved.
* License: https://github.com/bkaradzic/bgfx/blob/master/LICENSE
*/
#include "../common/common.sh"
float linstep(float _edge0, float _edge1, float _x)
{
return clamp((_x-_edge0)/(_edge1-_edge0), 0.0, 1.0);
}
float attenuation(float _dist, vec3 _attn)
{
return 1.0 / ( _attn.x //const
+ _attn.y * _dist //linear
+ _attn.z * _dist * _dist //quadrantic
);
}
float spot(float _ldotsd, float _inner, float _outer)
{
float inner = cos(radians(_inner));
float outer = cos(radians(min(_outer, _inner - 0.001)));
float spot = clamp((_ldotsd - inner) / (outer - inner), 0.0, 1.0);
return spot;
}
vec2 lit(vec3 _ld, vec3 _n, vec3 _vd, float _exp)
{
//diff
float ndotl = dot(_n, _ld);
//spec
vec3 r = 2.0*ndotl*_n - _ld; // reflect(_ld, _n);
float rdotv = dot(r, _vd);
float spec = step(0.0, ndotl) * pow(max(0.0, rdotv), _exp) * (2.0 + _exp)/8.0;
return max(vec2(ndotl, spec), 0.0);
}
struct Light
{
vec3 l;
vec3 ld;
float attn;
};
Light evalLight(vec3 _v, vec4 _l, vec3 _spotDirection, float _spotInner, float _spotOuter, vec3 _attnParams)
{
Light light;
//directional
light.l = _l.xyz;
light.ld = -normalize(light.l);
light.attn = 1.0;
if (0.0 != _l.w) //point or spot
{
light.l = _l.xyz - _v;
light.ld = normalize(light.l);
float ldotsd = max(0.0, dot(-light.ld, normalize(_spotDirection)));
float falloff = spot(ldotsd, _spotOuter, _spotInner);
light.attn = attenuation(length(light.l), _attnParams) * mix(falloff, 1.0, step(90, _spotOuter));
}
return light;
}
float texcoordInRange(vec2 _texcoord)
{
bool inRange = all(greaterThan(_texcoord, vec2_splat(0.0)))
&& all(lessThan (_texcoord, vec2_splat(1.0)))
;
return float(inRange);
}
float hardShadow(sampler2D _sampler, vec4 _shadowCoord, float _bias)
{
vec2 texCoord = _shadowCoord.xy/_shadowCoord.w;
bool outside = any(greaterThan(texCoord, vec2_splat(1.0)))
|| any(lessThan (texCoord, vec2_splat(0.0)))
;
if (outside)
{
return 1.0;
}
float receiver = (_shadowCoord.z-_bias)/_shadowCoord.w;
float occluder = unpackRgbaToFloat(texture2D(_sampler, texCoord) );
float visibility = step(receiver, occluder);
return visibility;
}
float PCF(sampler2D _sampler, vec4 _shadowCoord, float _bias, vec4 _pcfParams, vec2 _texelSize)
{
float result = 0.0;
vec2 offset = _pcfParams.zw * _texelSize * _shadowCoord.w;
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(-1.5, -1.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(-1.5, -0.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(-1.5, 0.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(-1.5, 1.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(-0.5, -1.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(-0.5, -0.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(-0.5, 0.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(-0.5, 1.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(0.5, -1.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(0.5, -0.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(0.5, 0.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(0.5, 1.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(1.5, -1.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(1.5, -0.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(1.5, 0.5) * offset, 0.0, 0.0), _bias);
result += hardShadow(_sampler, _shadowCoord + vec4(vec2(1.5, 1.5) * offset, 0.0, 0.0), _bias);
return result / 16.0;
}
float VSM(sampler2D _sampler, vec4 _shadowCoord, float _bias, float _depthMultiplier, float _minVariance)
{
vec2 texCoord = _shadowCoord.xy/_shadowCoord.w;
bool outside = any(greaterThan(texCoord, vec2_splat(1.0)))
|| any(lessThan (texCoord, vec2_splat(0.0)))
;
if (outside)
{
return 1.0;
}
float receiver = (_shadowCoord.z-_bias)/_shadowCoord.w * _depthMultiplier;
vec4 rgba = texture2D(_sampler, texCoord);
vec2 occluder = vec2(unpackHalfFloat(rgba.rg), unpackHalfFloat(rgba.ba)) * _depthMultiplier;
if (receiver < occluder.x)
{
return 1.0;
}
float variance = max(occluder.y - (occluder.x*occluder.x), _minVariance);
float d = receiver - occluder.x;
float visibility = variance / (variance + d*d);
return visibility;
}
float ESM(sampler2D _sampler, vec4 _shadowCoord, float _bias, float _depthMultiplier)
{
vec2 texCoord = _shadowCoord.xy/_shadowCoord.w;
bool outside = any(greaterThan(texCoord, vec2_splat(1.0)))
|| any(lessThan (texCoord, vec2_splat(0.0)))
;
if (outside)
{
return 1.0;
}
float receiver = (_shadowCoord.z-_bias)/_shadowCoord.w;
float occluder = unpackRgbaToFloat(texture2D(_sampler, texCoord) );
float visibility = clamp(exp(_depthMultiplier * (occluder-receiver) ), 0.0, 1.0);
return visibility;
}
vec4 blur9(sampler2D _sampler, vec2 _uv0, vec4 _uv1, vec4 _uv2, vec4 _uv3, vec4 _uv4)
{
#define _BLUR9_WEIGHT_0 1.0
#define _BLUR9_WEIGHT_1 0.9
#define _BLUR9_WEIGHT_2 0.55
#define _BLUR9_WEIGHT_3 0.18
#define _BLUR9_WEIGHT_4 0.1
#define _BLUR9_NORMALIZE (_BLUR9_WEIGHT_0+2.0*(_BLUR9_WEIGHT_1+_BLUR9_WEIGHT_2+_BLUR9_WEIGHT_3+_BLUR9_WEIGHT_4) )
#define BLUR9_WEIGHT(_x) (_BLUR9_WEIGHT_##_x/_BLUR9_NORMALIZE)
float blur;
blur = unpackRgbaToFloat(texture2D(_sampler, _uv0) * BLUR9_WEIGHT(0));
blur += unpackRgbaToFloat(texture2D(_sampler, _uv1.xy) * BLUR9_WEIGHT(1));
blur += unpackRgbaToFloat(texture2D(_sampler, _uv1.zw) * BLUR9_WEIGHT(1));
blur += unpackRgbaToFloat(texture2D(_sampler, _uv2.xy) * BLUR9_WEIGHT(2));
blur += unpackRgbaToFloat(texture2D(_sampler, _uv2.zw) * BLUR9_WEIGHT(2));
blur += unpackRgbaToFloat(texture2D(_sampler, _uv3.xy) * BLUR9_WEIGHT(3));
blur += unpackRgbaToFloat(texture2D(_sampler, _uv3.zw) * BLUR9_WEIGHT(3));
blur += unpackRgbaToFloat(texture2D(_sampler, _uv4.xy) * BLUR9_WEIGHT(4));
blur += unpackRgbaToFloat(texture2D(_sampler, _uv4.zw) * BLUR9_WEIGHT(4));
return packFloatToRgba(blur);
}
vec4 blur9VSM(sampler2D _sampler, vec2 _uv0, vec4 _uv1, vec4 _uv2, vec4 _uv3, vec4 _uv4)
{
#define _BLUR9_WEIGHT_0 1.0
#define _BLUR9_WEIGHT_1 0.9
#define _BLUR9_WEIGHT_2 0.55
#define _BLUR9_WEIGHT_3 0.18
#define _BLUR9_WEIGHT_4 0.1
#define _BLUR9_NORMALIZE (_BLUR9_WEIGHT_0+2.0*(_BLUR9_WEIGHT_1+_BLUR9_WEIGHT_2+_BLUR9_WEIGHT_3+_BLUR9_WEIGHT_4) )
#define BLUR9_WEIGHT(_x) (_BLUR9_WEIGHT_##_x/_BLUR9_NORMALIZE)
vec2 blur;
vec4 val;
val = texture2D(_sampler, _uv0) * BLUR9_WEIGHT(0);
blur = vec2(unpackHalfFloat(val.rg), unpackHalfFloat(val.ba));
val = texture2D(_sampler, _uv1.xy) * BLUR9_WEIGHT(1);
blur += vec2(unpackHalfFloat(val.rg), unpackHalfFloat(val.ba));
val = texture2D(_sampler, _uv1.zw) * BLUR9_WEIGHT(1);
blur += vec2(unpackHalfFloat(val.rg), unpackHalfFloat(val.ba));
val = texture2D(_sampler, _uv2.xy) * BLUR9_WEIGHT(2);
blur += vec2(unpackHalfFloat(val.rg), unpackHalfFloat(val.ba));
val = texture2D(_sampler, _uv2.zw) * BLUR9_WEIGHT(2);
blur += vec2(unpackHalfFloat(val.rg), unpackHalfFloat(val.ba));
val = texture2D(_sampler, _uv3.xy) * BLUR9_WEIGHT(3);
blur += vec2(unpackHalfFloat(val.rg), unpackHalfFloat(val.ba));
val = texture2D(_sampler, _uv3.zw) * BLUR9_WEIGHT(3);
blur += vec2(unpackHalfFloat(val.rg), unpackHalfFloat(val.ba));
val = texture2D(_sampler, _uv4.xy) * BLUR9_WEIGHT(4);
blur += vec2(unpackHalfFloat(val.rg), unpackHalfFloat(val.ba));
val = texture2D(_sampler, _uv4.zw) * BLUR9_WEIGHT(4);
blur += vec2(unpackHalfFloat(val.rg), unpackHalfFloat(val.ba));
return vec4(packHalfFloat(blur.x), packHalfFloat(blur.y));
}