lilium-voyager/code/renderergl2/glsl/lightall_fp.glsl

407 lines
10 KiB
GLSL

uniform sampler2D u_DiffuseMap;
#if defined(USE_LIGHTMAP)
uniform sampler2D u_LightMap;
#endif
#if defined(USE_NORMALMAP)
uniform sampler2D u_NormalMap;
#endif
#if defined(USE_DELUXEMAP)
uniform sampler2D u_DeluxeMap;
#endif
#if defined(USE_SPECULARMAP)
uniform sampler2D u_SpecularMap;
#endif
#if defined(USE_SHADOWMAP)
uniform sampler2D u_ShadowMap;
#endif
#if defined(USE_CUBEMAP)
uniform samplerCube u_CubeMap;
#endif
#if defined(USE_NORMALMAP) || defined(USE_DELUXEMAP) || defined(USE_SPECULARMAP) || defined(USE_CUBEMAP)
// y = deluxe, w = cube
uniform vec4 u_EnableTextures;
#endif
#if defined(USE_PRIMARY_LIGHT) || defined(USE_SHADOWMAP)
uniform vec3 u_PrimaryLightColor;
uniform vec3 u_PrimaryLightAmbient;
#endif
#if defined(USE_LIGHT) && !defined(USE_FAST_LIGHT)
uniform vec4 u_NormalScale;
uniform vec4 u_SpecularScale;
#endif
#if defined(USE_LIGHT) && !defined(USE_FAST_LIGHT)
#if defined(USE_CUBEMAP)
uniform vec4 u_CubeMapInfo;
#endif
#endif
varying vec4 var_TexCoords;
varying vec4 var_Color;
#if (defined(USE_LIGHT) && !defined(USE_FAST_LIGHT))
varying vec4 var_ColorAmbient;
#endif
#if (defined(USE_LIGHT) && !defined(USE_FAST_LIGHT))
varying vec4 var_Normal;
varying vec4 var_Tangent;
varying vec4 var_Bitangent;
#endif
#if defined(USE_LIGHT) && !defined(USE_FAST_LIGHT)
varying vec4 var_LightDir;
#endif
#if defined(USE_PRIMARY_LIGHT) || defined(USE_SHADOWMAP)
varying vec4 var_PrimaryLightDir;
#endif
#define EPSILON 0.00000001
#if defined(USE_PARALLAXMAP)
float SampleDepth(sampler2D normalMap, vec2 t)
{
#if defined(SWIZZLE_NORMALMAP)
return 1.0 - texture2D(normalMap, t).r;
#else
return 1.0 - texture2D(normalMap, t).a;
#endif
}
float RayIntersectDisplaceMap(vec2 dp, vec2 ds, sampler2D normalMap)
{
const int linearSearchSteps = 16;
const int binarySearchSteps = 6;
// current size of search window
float size = 1.0 / float(linearSearchSteps);
// current depth position
float depth = 0.0;
// best match found (starts with last position 1.0)
float bestDepth = 1.0;
// texture depth at best depth
float texDepth = 0.0;
float prevT = SampleDepth(normalMap, dp);
float prevTexDepth = prevT;
// search front to back for first point inside object
for(int i = 0; i < linearSearchSteps - 1; ++i)
{
depth += size;
float t = SampleDepth(normalMap, dp + ds * depth);
if(bestDepth > 0.996) // if no depth found yet
if(depth >= t)
{
bestDepth = depth; // store best depth
texDepth = t;
prevTexDepth = prevT;
}
prevT = t;
}
depth = bestDepth;
#if !defined (USE_RELIEFMAP)
float div = 1.0 / (1.0 + (prevTexDepth - texDepth) * float(linearSearchSteps));
bestDepth -= (depth - size - prevTexDepth) * div;
#else
// recurse around first point (depth) for closest match
for(int i = 0; i < binarySearchSteps; ++i)
{
size *= 0.5;
float t = SampleDepth(normalMap, dp + ds * depth);
if(depth >= t)
{
bestDepth = depth;
depth -= 2.0 * size;
}
depth += size;
}
#endif
return bestDepth;
}
#endif
vec3 CalcDiffuse(vec3 diffuseAlbedo, float NH, float EH, float roughness)
{
#if defined(USE_BURLEY)
// modified from https://disney-animation.s3.amazonaws.com/library/s2012_pbs_disney_brdf_notes_v2.pdf
float fd90 = -0.5 + EH * EH * roughness;
float burley = 1.0 + fd90 * 0.04 / NH;
burley *= burley;
return diffuseAlbedo * burley;
#else
return diffuseAlbedo;
#endif
}
vec3 EnvironmentBRDF(float roughness, float NE, vec3 specular)
{
// from http://community.arm.com/servlet/JiveServlet/download/96891546-19496/siggraph2015-mmg-renaldas-slides.pdf
float v = 1.0 - max(roughness, NE);
v *= v * v;
return vec3(v) + specular;
}
vec3 CalcSpecular(vec3 specular, float NH, float EH, float roughness)
{
// from http://community.arm.com/servlet/JiveServlet/download/96891546-19496/siggraph2015-mmg-renaldas-slides.pdf
float rr = roughness*roughness;
float rrrr = rr*rr;
float d = (NH * NH) * (rrrr - 1.0) + 1.0;
float v = (EH * EH) * (roughness + 0.5);
return specular * (rrrr / (4.0 * d * d * v));
}
float CalcLightAttenuation(float point, float normDist)
{
// zero light at 1.0, approximating q3 style
// also don't attenuate directional light
float attenuation = (0.5 * normDist - 1.5) * point + 1.0;
// clamp attenuation
#if defined(NO_LIGHT_CLAMP)
attenuation = max(attenuation, 0.0);
#else
attenuation = clamp(attenuation, 0.0, 1.0);
#endif
return attenuation;
}
void main()
{
vec3 viewDir, lightColor, ambientColor, reflectance;
vec3 L, N, E, H;
float NL, NH, NE, EH, attenuation;
#if defined(USE_LIGHT) && !defined(USE_FAST_LIGHT)
mat3 tangentToWorld = mat3(var_Tangent.xyz, var_Bitangent.xyz, var_Normal.xyz);
viewDir = vec3(var_Normal.w, var_Tangent.w, var_Bitangent.w);
E = normalize(viewDir);
#endif
lightColor = var_Color.rgb;
#if defined(USE_LIGHTMAP)
vec4 lightmapColor = texture2D(u_LightMap, var_TexCoords.zw);
#if defined(RGBM_LIGHTMAP)
lightmapColor.rgb *= lightmapColor.a;
#endif
#if defined(USE_PBR) && !defined(USE_FAST_LIGHT)
lightmapColor.rgb *= lightmapColor.rgb;
#endif
lightColor *= lightmapColor.rgb;
#endif
vec2 texCoords = var_TexCoords.xy;
#if defined(USE_PARALLAXMAP)
vec3 offsetDir = viewDir * tangentToWorld;
offsetDir.xy *= -u_NormalScale.a / offsetDir.z;
texCoords += offsetDir.xy * RayIntersectDisplaceMap(texCoords, offsetDir.xy, u_NormalMap);
#endif
vec4 diffuse = texture2D(u_DiffuseMap, texCoords);
#if defined(USE_LIGHT) && !defined(USE_FAST_LIGHT)
L = var_LightDir.xyz;
#if defined(USE_DELUXEMAP)
L += (texture2D(u_DeluxeMap, var_TexCoords.zw).xyz - vec3(0.5)) * u_EnableTextures.y;
#endif
float sqrLightDist = dot(L, L);
L /= sqrt(sqrLightDist);
#if defined(USE_LIGHT_VECTOR)
attenuation = CalcLightAttenuation(float(var_LightDir.w > 0.0), var_LightDir.w / sqrLightDist);
#else
attenuation = 1.0;
#endif
#if defined(USE_NORMALMAP)
#if defined(SWIZZLE_NORMALMAP)
N.xy = texture2D(u_NormalMap, texCoords).ag - vec2(0.5);
#else
N.xy = texture2D(u_NormalMap, texCoords).rg - vec2(0.5);
#endif
N.xy *= u_NormalScale.xy;
N.z = sqrt(clamp((0.25 - N.x * N.x) - N.y * N.y, 0.0, 1.0));
N = tangentToWorld * N;
#else
N = var_Normal.xyz;
#endif
N = normalize(N);
#if defined(USE_SHADOWMAP)
vec2 shadowTex = gl_FragCoord.xy * r_FBufScale;
float shadowValue = texture2D(u_ShadowMap, shadowTex).r;
// surfaces not facing the light are always shadowed
shadowValue *= clamp(dot(N, var_PrimaryLightDir.xyz), 0.0, 1.0);
#if defined(SHADOWMAP_MODULATE)
lightColor *= shadowValue * (1.0 - u_PrimaryLightAmbient.r) + u_PrimaryLightAmbient.r;
#endif
#endif
#if !defined(USE_LIGHT_VECTOR)
ambientColor = lightColor;
float surfNL = clamp(dot(var_Normal.xyz, L), 0.0, 1.0);
// Scale the incoming light to compensate for the baked-in light angle
// attenuation.
lightColor /= max(surfNL, 0.25);
// Recover any unused light as ambient, in case attenuation is over 4x or
// light is below the surface
ambientColor = max(ambientColor - lightColor * surfNL, vec3(0.0));
#else
ambientColor = var_ColorAmbient.rgb;
#endif
NL = clamp(dot(N, L), 0.0, 1.0);
NE = clamp(dot(N, E), 0.0, 1.0);
#if defined(USE_SPECULARMAP)
vec4 specular = texture2D(u_SpecularMap, texCoords);
#else
vec4 specular = vec4(1.0);
#endif
specular *= u_SpecularScale;
#if defined(USE_PBR)
diffuse.rgb *= diffuse.rgb;
#endif
#if defined(USE_PBR)
// diffuse rgb is base color
// specular red is gloss
// specular green is metallicness
float gloss = specular.r;
float metal = specular.g;
specular.rgb = metal * diffuse.rgb + vec3(0.04 - 0.04 * metal);
diffuse.rgb *= 1.0 - metal;
#else
// diffuse rgb is diffuse
// specular rgb is specular reflectance at normal incidence
// specular alpha is gloss
float gloss = specular.a;
// adjust diffuse by specular reflectance, to maintain energy conservation
diffuse.rgb *= vec3(1.0) - specular.rgb;
#endif
#if defined(GLOSS_IS_GLOSS)
float roughness = exp2(-3.0 * gloss);
#elif defined(GLOSS_IS_SMOOTHNESS)
float roughness = 1.0 - gloss;
#elif defined(GLOSS_IS_ROUGHNESS)
float roughness = gloss;
#elif defined(GLOSS_IS_SHININESS)
float roughness = pow(2.0 / (8190.0 * gloss + 2.0), 0.25);
#endif
reflectance = CalcDiffuse(diffuse.rgb, NH, EH, roughness);
gl_FragColor.rgb = lightColor * reflectance * (attenuation * NL);
gl_FragColor.rgb += ambientColor * diffuse.rgb;
#if defined(USE_CUBEMAP)
reflectance = EnvironmentBRDF(roughness, NE, specular.rgb);
vec3 R = reflect(E, N);
// parallax corrected cubemap (cheaper trick)
// from http://seblagarde.wordpress.com/2012/09/29/image-based-lighting-approaches-and-parallax-corrected-cubemap/
vec3 parallax = u_CubeMapInfo.xyz + u_CubeMapInfo.w * viewDir;
vec3 cubeLightColor = textureCubeLod(u_CubeMap, R + parallax, ROUGHNESS_MIPS * roughness).rgb * u_EnableTextures.w;
// normalize cubemap based on last roughness mip (~diffuse)
// multiplying cubemap values by lighting below depends on either this or the cubemap being normalized at generation
//vec3 cubeLightDiffuse = max(textureCubeLod(u_CubeMap, N, ROUGHNESS_MIPS).rgb, 0.5 / 255.0);
//cubeLightColor /= dot(cubeLightDiffuse, vec3(0.2125, 0.7154, 0.0721));
#if defined(USE_PBR)
cubeLightColor *= cubeLightColor;
#endif
// multiply cubemap values by lighting
// not technically correct, but helps make reflections look less unnatural
//cubeLightColor *= lightColor * (attenuation * NL) + ambientColor;
gl_FragColor.rgb += cubeLightColor * reflectance;
#endif
#if defined(USE_PRIMARY_LIGHT) || defined(SHADOWMAP_MODULATE)
vec3 L2, H2;
float NL2, EH2, NH2;
L2 = var_PrimaryLightDir.xyz;
// enable when point lights are supported as primary lights
//sqrLightDist = dot(L2, L2);
//L2 /= sqrt(sqrLightDist);
NL2 = clamp(dot(N, L2), 0.0, 1.0);
H2 = normalize(L2 + E);
EH2 = clamp(dot(E, H2), 0.0, 1.0);
NH2 = clamp(dot(N, H2), 0.0, 1.0);
reflectance = CalcSpecular(specular.rgb, NH2, EH2, roughness);
// bit of a hack, with modulated shadowmaps, ignore diffuse
#if !defined(SHADOWMAP_MODULATE)
reflectance += CalcDiffuse(diffuse.rgb, NH2, EH2, roughness);
#endif
lightColor = u_PrimaryLightColor;
#if defined(USE_SHADOWMAP)
lightColor *= shadowValue;
#endif
// enable when point lights are supported as primary lights
//lightColor *= CalcLightAttenuation(float(u_PrimaryLightDir.w > 0.0), u_PrimaryLightDir.w / sqrLightDist);
gl_FragColor.rgb += lightColor * reflectance * NL2;
#endif
#if defined(USE_PBR)
gl_FragColor.rgb = sqrt(gl_FragColor.rgb);
#endif
#else
gl_FragColor.rgb = diffuse.rgb * lightColor;
#endif
gl_FragColor.a = diffuse.a * var_Color.a;
}