diff options
Diffstat (limited to 'intern/cycles/kernel/osl/nodes/node_fresnel.h')
| -rw-r--r-- | intern/cycles/kernel/osl/nodes/node_fresnel.h | 27 |
1 files changed, 21 insertions, 6 deletions
diff --git a/intern/cycles/kernel/osl/nodes/node_fresnel.h b/intern/cycles/kernel/osl/nodes/node_fresnel.h index 0c8a5276ede..dfd0a23fe1e 100644 --- a/intern/cycles/kernel/osl/nodes/node_fresnel.h +++ b/intern/cycles/kernel/osl/nodes/node_fresnel.h @@ -1,17 +1,32 @@ - +/* + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software Foundation, + * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + float fresnel_dielectric(vector Incoming, normal Normal, float eta) { /* compute fresnel reflectance without explicitly computing - the refracted direction */ + * the refracted direction */ float c = fabs(dot(Incoming, Normal)); float g = eta * eta - 1 + c * c; float result; - if(g > 0) { + if (g > 0) { g = sqrt(g); - float A =(g - c)/(g + c); - float B =(c *(g + c)- 1)/(c *(g - c)+ 1); - result = 0.5 * A * A *(1 + B * B); + float A = (g - c) / (g + c); + float B = (c * (g + c) - 1) / (c * (g - c) + 1); + result = 0.5 * A * A * (1 + B * B); } else result = 1.0; /* TIR (no refracted component) */ |