diff options
-rw-r--r-- | drivers/gles2/shaders/scene.glsl | 103 | ||||
-rw-r--r-- | drivers/gles3/shaders/scene.glsl | 48 |
2 files changed, 94 insertions, 57 deletions
diff --git a/drivers/gles2/shaders/scene.glsl b/drivers/gles2/shaders/scene.glsl index 958de94485..42b50790b2 100644 --- a/drivers/gles2/shaders/scene.glsl +++ b/drivers/gles2/shaders/scene.glsl @@ -898,10 +898,11 @@ varying vec2 uv2_interp; varying vec3 view_interp; -vec3 metallic_to_specular_color(float metallic, float specular, vec3 albedo) { - float dielectric = (0.034 * 2.0) * specular; - // energy conservation - return mix(vec3(dielectric), albedo, metallic); // TODO: reference? +vec3 F0(float metallic, float specular, vec3 albedo) { + float dielectric = 0.16 * specular * specular; + // use albedo * metallic as colored specular reflectance at 0 angle for metallic materials; + // see https://google.github.io/filament/Filament.md.html + return mix(vec3(dielectric), albedo, vec3(metallic)); } /* clang-format off */ @@ -934,6 +935,7 @@ varying highp float dp_clip; // E. Heitz, "Understanding the Masking-Shadowing Function in Microfacet-Based BRDFs", J. Comp. Graph. Tech. 3 (2) (2014). // Eqns 71-72 and 85-86 (see also Eqns 43 and 80). +/* float G_GGX_2cos(float cos_theta_m, float alpha) { // Schlick's approximation // C. Schlick, "An Inexpensive BRDF Model for Physically-based Rendering", Computer Graphics Forum. 13 (3): 233 (1994) @@ -946,6 +948,15 @@ float G_GGX_2cos(float cos_theta_m, float alpha) { // float sin2 = (1.0 - cos2); // return 1.0 / (cos_theta_m + sqrt(cos2 + alpha * alpha * sin2)); } +*/ + +// This approximates G_GGX_2cos(cos_theta_l, alpha) * G_GGX_2cos(cos_theta_v, alpha) +// See Filament docs, Specular G section. +float V_GGX(float cos_theta_l, float cos_theta_v, float alpha) { + float v = cos_theta_l * (cos_theta_v * (1.0 - alpha) + alpha); + float l = cos_theta_v * (cos_theta_l * (1.0 - alpha) + alpha); + return 0.5 / (v + l); +} float D_GGX(float cos_theta_m, float alpha) { float alpha2 = alpha * alpha; @@ -953,6 +964,7 @@ float D_GGX(float cos_theta_m, float alpha) { return alpha2 / (M_PI * d * d); } +/* float G_GGX_anisotropic_2cos(float cos_theta_m, float alpha_x, float alpha_y, float cos_phi, float sin_phi) { float cos2 = cos_theta_m * cos_theta_m; float sin2 = (1.0 - cos2); @@ -960,14 +972,30 @@ float G_GGX_anisotropic_2cos(float cos_theta_m, float alpha_x, float alpha_y, fl float s_y = alpha_y * sin_phi; return 1.0 / max(cos_theta_m + sqrt(cos2 + (s_x * s_x + s_y * s_y) * sin2), 0.001); } +*/ -float D_GGX_anisotropic(float cos_theta_m, float alpha_x, float alpha_y, float cos_phi, float sin_phi) { - float cos2 = cos_theta_m * cos_theta_m; +// This approximates G_GGX_anisotropic_2cos(cos_theta_l, ...) * G_GGX_anisotropic_2cos(cos_theta_v, ...) +// See Filament docs, Anisotropic specular BRDF section. +float V_GGX_anisotropic(float alpha_x, float alpha_y, float TdotV, float TdotL, float BdotV, float BdotL, float NdotV, float NdotL) { + float Lambda_V = NdotL * length(vec3(alpha_x * TdotV, alpha_y * BdotV, NdotV)); + float Lambda_L = NdotV * length(vec3(alpha_x * TdotL, alpha_y * BdotL, NdotL)); + return 0.5 / (Lambda_V + Lambda_L); +} + +float D_GGX_anisotropic(float cos_theta_m, float alpha_x, float alpha_y, float cos_phi, float sin_phi, float NdotH) { + float alpha2 = alpha_x * alpha_y; + highp vec3 v = vec3(alpha_y * cos_phi, alpha_x * sin_phi, alpha2 * NdotH); + highp float v2 = dot(v, v); + float w2 = alpha2 / v2; + float D = alpha2 * w2 * w2 * (1.0 / M_PI); + return D; + + /* float cos2 = cos_theta_m * cos_theta_m; float sin2 = (1.0 - cos2); float r_x = cos_phi / alpha_x; float r_y = sin_phi / alpha_y; float d = cos2 + sin2 * (r_x * r_x + r_y * r_y); - return 1.0 / max(M_PI * alpha_x * alpha_y * d * d, 0.001); + return 1.0 / max(M_PI * alpha_x * alpha_y * d * d, 0.001); */ } float SchlickFresnel(float u) { @@ -996,6 +1024,7 @@ void light_compute( float specular_blob_intensity, float roughness, float metallic, + float specular, float rim, float rim_tint, float clearcoat, @@ -1112,9 +1141,11 @@ LIGHT_SHADER_CODE if (roughness > 0.0) { - // D - - float specular_brdf_NL; +#if defined(SPECULAR_SCHLICK_GGX) + vec3 specular_brdf_NL = vec3(0.0); +#else + float specular_brdf_NL = 0.0; +#endif #if defined(SPECULAR_BLINN) @@ -1147,7 +1178,6 @@ LIGHT_SHADER_CODE #elif defined(SPECULAR_DISABLED) // none.. - specular_brdf_NL = 0.0; #elif defined(SPECULAR_SCHLICK_GGX) // shlick+ggx as default @@ -1157,28 +1187,28 @@ LIGHT_SHADER_CODE float cLdotH = max(dot(L, H), 0.0); #if defined(LIGHT_USE_ANISOTROPY) - + float alpha = roughness * roughness; float aspect = sqrt(1.0 - anisotropy * 0.9); - float rx = roughness / aspect; - float ry = roughness * aspect; - float ax = rx * rx; - float ay = ry * ry; - float XdotH = dot(T, H); - float YdotH = dot(B, H); - float D = D_GGX_anisotropic(cNdotH, ax, ay, XdotH, YdotH); - float G = G_GGX_anisotropic_2cos(cNdotL, ax, ay, XdotH, YdotH) * G_GGX_anisotropic_2cos(cNdotV, ax, ay, XdotH, YdotH); + float ax = alpha / aspect; + float ay = alpha * aspect; + //float XdotH = dot(T, H); + //float YdotH = dot(B, H); + float D = D_GGX_anisotropic(cNdotH, ax, ay, XdotH, YdotH, cNdotH); + //float G = G_GGX_anisotropic_2cos(cNdotL, ax, ay, XdotH, YdotH) * G_GGX_anisotropic_2cos(cNdotV, ax, ay, XdotH, YdotH); + float G = V_GGX_anisotropic(ax, ay, dot(T, V), dot(T, L), dot(B, V), dot(B, L), cNdotV, cNdotL)) #else float alpha = roughness * roughness; float D = D_GGX(cNdotH, alpha); - float G = G_GGX_2cos(cNdotL, alpha) * G_GGX_2cos(cNdotV, alpha); + //float G = G_GGX_2cos(cNdotL, alpha) * G_GGX_2cos(cNdotV, alpha); + float G = V_GGX(cNdotL, cNdotV, alpha); #endif // F - //float F0 = 1.0; - //float cLdotH5 = SchlickFresnel(cLdotH); - //float F = mix(cLdotH5, 1.0, F0); + vec3 f0 = F0(metallic, specular, diffuse_color); + float cLdotH5 = SchlickFresnel(cLdotH); + vec3 F = mix(vec3(cLdotH5), vec3(1.0), f0); - specular_brdf_NL = cNdotL * D /* F */ * G; + specular_brdf_NL = cNdotL * D * F * G; #endif @@ -1197,11 +1227,12 @@ LIGHT_SHADER_CODE #endif float Dr = GTR1(cNdotH, mix(.1, .001, clearcoat_gloss)); float Fr = mix(.04, 1.0, cLdotH5); - float Gr = G_GGX_2cos(cNdotL, .25) * G_GGX_2cos(cNdotV, .25); + //float Gr = G_GGX_2cos(cNdotL, .25) * G_GGX_2cos(cNdotV, .25); + float Gr = V_GGX(cNdotL, cNdotV, 0.25); - float specular_brdf_NL = 0.25 * clearcoat * Gr * Fr * Dr * cNdotL; + float clearcoat_specular_brdf_NL = 0.25 * clearcoat * Gr * Fr * Dr * cNdotL; - specular_light += specular_brdf_NL * light_color * specular_blob_intensity * attenuation; + specular_light += clearcoat_specular_brdf_NL * light_color * specular_blob_intensity * attenuation; } #endif } @@ -1290,6 +1321,11 @@ void main() { float alpha = 1.0; float side = 1.0; + float specular_blob_intensity = 1.0; +#if defined(SPECULAR_TOON) + specular_blob_intensity *= specular * 2.0; +#endif + #if defined(ENABLE_AO) float ao = 1.0; float ao_light_affect = 0.0; @@ -1808,7 +1844,7 @@ FRAGMENT_SHADER_CODE #ifdef USE_VERTEX_LIGHTING //vertex lighting - specular_light += specular_interp * specular * light_att; + specular_light += specular_interp * specular_blob_intensity * light_att; diffuse_light += diffuse_interp * albedo * light_att; #else @@ -1823,9 +1859,10 @@ FRAGMENT_SHADER_CODE light_att, albedo, transmission, - specular * light_specular, + specular_blob_intensity * light_specular, roughness, metallic, + specular, rim, rim_tint, clearcoat, @@ -1872,10 +1909,10 @@ FRAGMENT_SHADER_CODE vec4 r = roughness * c0 + c1; float ndotv = clamp(dot(normal, eye_position), 0.0, 1.0); float a004 = min(r.x * r.x, exp2(-9.28 * ndotv)) * r.x + r.y; - vec2 AB = vec2(-1.04, 1.04) * a004 + r.zw; + vec2 env = vec2(-1.04, 1.04) * a004 + r.zw; - vec3 specular_color = metallic_to_specular_color(metallic, specular, albedo); - specular_light *= AB.x * specular_color + AB.y; + vec3 f0 = F0(metallic, specular, albedo); + specular_light *= env.x * f0 + env.y; #endif } diff --git a/drivers/gles3/shaders/scene.glsl b/drivers/gles3/shaders/scene.glsl index bcaf4a57a8..598bd3465e 100644 --- a/drivers/gles3/shaders/scene.glsl +++ b/drivers/gles3/shaders/scene.glsl @@ -920,13 +920,14 @@ float GTR1(float NdotH, float a) { return (a2 - 1.0) / (M_PI * log(a2) * t); } -vec3 metallic_to_specular_color(float metallic, float specular, vec3 albedo) { - float dielectric = (0.034 * 2.0) * specular; - // energy conservation - return mix(vec3(dielectric), albedo, metallic); // TODO: reference? +vec3 F0(float metallic, float specular, vec3 albedo) { + float dielectric = 0.16 * specular * specular; + // use albedo * metallic as colored specular reflectance at 0 angle for metallic materials; + // see https://google.github.io/filament/Filament.md.html + return mix(vec3(dielectric), albedo, vec3(metallic)); } -void light_compute(vec3 N, vec3 L, vec3 V, vec3 B, vec3 T, vec3 light_color, vec3 attenuation, vec3 diffuse_color, vec3 transmission, float specular_blob_intensity, float roughness, float metallic, float rim, float rim_tint, float clearcoat, float clearcoat_gloss, float anisotropy, inout vec3 diffuse_light, inout vec3 specular_light) { +void light_compute(vec3 N, vec3 L, vec3 V, vec3 B, vec3 T, vec3 light_color, vec3 attenuation, vec3 diffuse_color, vec3 transmission, float specular_blob_intensity, float roughness, float metallic, float specular, float rim, float rim_tint, float clearcoat, float clearcoat_gloss, float anisotropy, inout vec3 diffuse_light, inout vec3 specular_light) { #if defined(USE_LIGHT_SHADER_CODE) // light is written by the light shader @@ -1069,11 +1070,10 @@ LIGHT_SHADER_CODE #if defined(LIGHT_USE_ANISOTROPY) + float alpha = roughness * roughness; float aspect = sqrt(1.0 - anisotropy * 0.9); - float rx = roughness / aspect; - float ry = roughness * aspect; - float ax = rx * rx; - float ay = ry * ry; + float ax = alpha / aspect; + float ay = alpha * aspect; float XdotH = dot(T, H); float YdotH = dot(B, H); float D = D_GGX_anisotropic(cNdotH, ax, ay, XdotH, YdotH); @@ -1085,11 +1085,11 @@ LIGHT_SHADER_CODE float G = G_GGX_2cos(cNdotL, alpha) * G_GGX_2cos(cNdotV, alpha); #endif // F - //float F0 = 1.0; - //float cLdotH5 = SchlickFresnel(cLdotH); - //float F = mix(cLdotH5, 1.0, F0); + vec3 f0 = F0(metallic, specular, diffuse_color); + float cLdotH5 = SchlickFresnel(cLdotH); + vec3 F = mix(vec3(cLdotH5), vec3(1.0), f0); - float specular_brdf_NL = cNdotL * D /* F */ * G; + vec3 specular_brdf_NL = cNdotL * D * F * G; specular_light += specular_brdf_NL * light_color * specular_blob_intensity * attenuation; #endif @@ -1191,7 +1191,7 @@ vec3 light_transmittance(float translucency,vec3 light_vec, vec3 normal, vec3 po } #endif -void light_process_omni(int idx, vec3 vertex, vec3 eye_vec, vec3 normal, vec3 binormal, vec3 tangent, vec3 albedo, vec3 transmission, float roughness, float metallic, float rim, float rim_tint, float clearcoat, float clearcoat_gloss, float anisotropy, float p_blob_intensity, inout vec3 diffuse_light, inout vec3 specular_light) { +void light_process_omni(int idx, vec3 vertex, vec3 eye_vec, vec3 normal, vec3 binormal, vec3 tangent, vec3 albedo, vec3 transmission, float roughness, float metallic, float specular, float rim, float rim_tint, float clearcoat, float clearcoat_gloss, float anisotropy, float p_blob_intensity, inout vec3 diffuse_light, inout vec3 specular_light) { vec3 light_rel_vec = omni_lights[idx].light_pos_inv_radius.xyz - vertex; float light_length = length(light_rel_vec); @@ -1245,10 +1245,10 @@ void light_process_omni(int idx, vec3 vertex, vec3 eye_vec, vec3 normal, vec3 bi light_attenuation *= mix(omni_lights[idx].shadow_color_contact.rgb, vec3(1.0), shadow); } #endif //SHADOWS_DISABLED - light_compute(normal, normalize(light_rel_vec), eye_vec, binormal, tangent, omni_lights[idx].light_color_energy.rgb, light_attenuation, albedo, transmission, omni_lights[idx].light_params.z * p_blob_intensity, roughness, metallic, rim * omni_attenuation, rim_tint, clearcoat, clearcoat_gloss, anisotropy, diffuse_light, specular_light); + light_compute(normal, normalize(light_rel_vec), eye_vec, binormal, tangent, omni_lights[idx].light_color_energy.rgb, light_attenuation, albedo, transmission, omni_lights[idx].light_params.z * p_blob_intensity, roughness, metallic, specular, rim * omni_attenuation, rim_tint, clearcoat, clearcoat_gloss, anisotropy, diffuse_light, specular_light); } -void light_process_spot(int idx, vec3 vertex, vec3 eye_vec, vec3 normal, vec3 binormal, vec3 tangent, vec3 albedo, vec3 transmission, float roughness, float metallic, float rim, float rim_tint, float clearcoat, float clearcoat_gloss, float anisotropy, float p_blob_intensity, inout vec3 diffuse_light, inout vec3 specular_light) { +void light_process_spot(int idx, vec3 vertex, vec3 eye_vec, vec3 normal, vec3 binormal, vec3 tangent, vec3 albedo, vec3 transmission, float roughness, float metallic, float specular, float rim, float rim_tint, float clearcoat, float clearcoat_gloss, float anisotropy, float p_blob_intensity, inout vec3 diffuse_light, inout vec3 specular_light) { vec3 light_rel_vec = spot_lights[idx].light_pos_inv_radius.xyz - vertex; float light_length = length(light_rel_vec); @@ -1280,7 +1280,7 @@ void light_process_spot(int idx, vec3 vertex, vec3 eye_vec, vec3 normal, vec3 bi } #endif //SHADOWS_DISABLED - light_compute(normal, normalize(light_rel_vec), eye_vec, binormal, tangent, spot_lights[idx].light_color_energy.rgb, light_attenuation, albedo, transmission, spot_lights[idx].light_params.z * p_blob_intensity, roughness, metallic, rim * spot_attenuation, rim_tint, clearcoat, clearcoat_gloss, anisotropy, diffuse_light, specular_light); + light_compute(normal, normalize(light_rel_vec), eye_vec, binormal, tangent, spot_lights[idx].light_color_energy.rgb, light_attenuation, albedo, transmission, spot_lights[idx].light_params.z * p_blob_intensity, roughness, metallic, specular, rim * spot_attenuation, rim_tint, clearcoat, clearcoat_gloss, anisotropy, diffuse_light, specular_light); } void reflection_process(int idx, vec3 vertex, vec3 normal, vec3 binormal, vec3 tangent, float roughness, float anisotropy, vec3 ambient, vec3 skybox, inout highp vec4 reflection_accum, inout highp vec4 ambient_accum) { @@ -1895,7 +1895,7 @@ FRAGMENT_SHADER_CODE specular_light *= mix(vec3(1.0), light_attenuation, specular_light_interp.a); #else - light_compute(normal, -light_direction_attenuation.xyz, eye_vec, binormal, tangent, light_color_energy.rgb, light_attenuation, albedo, transmission, light_params.z * specular_blob_intensity, roughness, metallic, rim, rim_tint, clearcoat, clearcoat_gloss, anisotropy, diffuse_light, specular_light); + light_compute(normal, -light_direction_attenuation.xyz, eye_vec, binormal, tangent, light_color_energy.rgb, light_attenuation, albedo, transmission, light_params.z * specular_blob_intensity, roughness, metallic, specular, rim, rim_tint, clearcoat, clearcoat_gloss, anisotropy, diffuse_light, specular_light); #endif #endif //#USE_LIGHT_DIRECTIONAL @@ -1969,11 +1969,11 @@ FRAGMENT_SHADER_CODE #else for (int i = 0; i < omni_light_count; i++) { - light_process_omni(omni_light_indices[i], vertex, eye_vec, normal, binormal, tangent, albedo, transmission, roughness, metallic, rim, rim_tint, clearcoat, clearcoat_gloss, anisotropy, specular_blob_intensity, diffuse_light, specular_light); + light_process_omni(omni_light_indices[i], vertex, eye_vec, normal, binormal, tangent, albedo, transmission, roughness, metallic, specular, rim, rim_tint, clearcoat, clearcoat_gloss, anisotropy, specular_blob_intensity, diffuse_light, specular_light); } for (int i = 0; i < spot_light_count; i++) { - light_process_spot(spot_light_indices[i], vertex, eye_vec, normal, binormal, tangent, albedo, transmission, roughness, metallic, rim, rim_tint, clearcoat, clearcoat_gloss, anisotropy, specular_blob_intensity, diffuse_light, specular_light); + light_process_spot(spot_light_indices[i], vertex, eye_vec, normal, binormal, tangent, albedo, transmission, roughness, metallic, specular, rim, rim_tint, clearcoat, clearcoat_gloss, anisotropy, specular_blob_intensity, diffuse_light, specular_light); } #endif //USE_VERTEX_LIGHTING @@ -1994,7 +1994,7 @@ FRAGMENT_SHADER_CODE diffuse_light *= ao_light_affect; #endif - //energy conservation + // base color remapping diffuse_light *= 1.0 - metallic; // TODO: avoid all diffuse and ambient light calculations when metallic == 1 up to this point ambient_light *= 1.0 - metallic; @@ -2011,10 +2011,10 @@ FRAGMENT_SHADER_CODE vec4 r = roughness * c0 + c1; float ndotv = clamp(dot(normal, eye_vec), 0.0, 1.0); float a004 = min(r.x * r.x, exp2(-9.28 * ndotv)) * r.x + r.y; - vec2 AB = vec2(-1.04, 1.04) * a004 + r.zw; + vec2 env = vec2(-1.04, 1.04) * a004 + r.zw; - vec3 specular_color = metallic_to_specular_color(metallic, specular, albedo); - specular_light *= AB.x * specular_color + AB.y; + vec3 f0 = F0(metallic, specular, albedo); + specular_light *= env.x * f0 + env.y; #endif } |