hoosiertransfer-mod/desktopRuntime/resources/assets/eagler/glsl/deferred/lib/pbr_lighting.glsl

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3.1 KiB
GLSL

/*
* Copyright (c) 2023 lax1dude. All Rights Reserved.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
*/
#ifdef LIB_INCLUDE_PBR_LIGHTING_FUNCTION
#ifndef _HAS_PBR_LIGHTING_FUNCTION
#define _HAS_PBR_LIGHTING_FUNCTION
#ifdef LIB_INCLUDE_PBR_LIGHTING_PREFETCH
#define PREFETCH_METALS(albedo, materialG1f, metalN3f, metalK3f)\
if(materialG1f >= 0.9 && materialG1f < 0.964) {\
metalK3f.xy = vec2(0.25, (materialG1f - 0.9) * 15.625);\
metalN3f = textureLod(u_metalsLUT, metalK3f.xy, 0.0).rgb;\
metalK3f.x += 0.5;\
metalK3f = textureLod(u_metalsLUT, metalK3f.xy, 0.0).rgb;\
}
#endif
#ifdef LIB_INCLUDE_PBR_LIGHTING_PREFETCH
vec3 eaglercraftLighting(in vec3 albedo, in vec3 radiance, in vec3 viewDir, in vec3 lightDir, in vec3 normalVec, in vec3 materials, in vec3 metalN, in vec3 metalK) {
#else
vec3 eaglercraftLighting(in vec3 albedo, in vec3 radiance, in vec3 viewDir, in vec3 lightDir, in vec3 normalVec, in vec3 materials) {
#endif
float roughness = 1.0 - materials.r * 0.85;
vec3 H = normalize(viewDir + lightDir);
vec3 NdotHVL = max(normalVec * mat3(H, viewDir, lightDir), vec3(0.0));
float NDF = roughness * roughness;
NDF *= NDF;
float denom = NdotHVL.x * NdotHVL.x * (NDF - 1.0) + 1.0;
NDF /= denom * denom * 3.141592;
float gs = roughness + 1.0;
gs *= gs * 0.125;
vec2 Ndot = NdotHVL.yz;
Ndot /= Ndot * (1.0 - gs) + gs;
NDF *= Ndot.x * Ndot.y;
float fresnel = pow(max(1.0 - NdotHVL.x, 0.0), 5.0);
vec3 kD = vec3(0.03);
vec3 F;
if(materials.g < 0.9) {
F = vec3(materials.g + (1.0 - materials.g) * fresnel);
kD = (1.0 - F) * albedo / 3.141592;
}else if(materials.g < 0.964) {
#ifdef LIB_INCLUDE_PBR_LIGHTING_PREFETCH
vec3 mN = metalN;
vec3 mK = metalK;
#else
vec2 lutUV = vec2(0.25, (materials.g - 0.9) * 15.625);
vec3 mN = textureLod(u_metalsLUT, lutUV, 0.0).rgb;
lutUV.x += 0.5;
vec3 mK = textureLod(u_metalsLUT, lutUV, 0.0).rgb * length(albedo);
#endif
fresnel = 1.0 - fresnel;
mK *= mK;
mK += mN * mN;
vec3 nv = mN * fresnel * 2.0;
fresnel *= fresnel;
vec3 num = mK - nv + fresnel;
vec3 den = mK + nv + fresnel;
vec3 r = num / den;
mK *= fresnel;
mK += 1.0;
num = mK - nv;
den = mK + nv;
r += num / den;
r = clamp(r * 0.5, vec3(0.0), vec3(1.0));
F = r * r;
}else {
F = albedo + (1.0 - albedo) * fresnel;
}
denom = 4.0 * NdotHVL.y * NdotHVL.z + 0.0001;
return (kD + (NDF * F / denom)) * radiance * NdotHVL.z;
}
#endif
#endif