mitsuba/src/medium/materials.h

202 lines
11 KiB
C++

/*
This file is part of Mitsuba, a physically based rendering system.
Copyright (c) 2007-2014 by Wenzel Jakob and others.
Mitsuba is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License Version 3
as published by the Free Software Foundation.
Mitsuba 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, see <http://www.gnu.org/licenses/>.
*/
#if !defined(__MATERIAL_DATA_H)
#define __MATERIAL_DATA_H
#include "../bsdfs/ior.h"
MTS_NAMESPACE_BEGIN
struct MaterialEntry {
const char *name;
Float sigmaS[3];
Float sigmaA[3];
Float g[3];
Float eta;
};
static MaterialEntry materialData[] = {
/* Fitted data from "A Practical Model for Subsurface scattering" (Jensen et al.). No anisotropy data available. */
{ "Apple", { 2.29f, 2.39f, 1.97f }, { 0.0030f, 0.0034f, 0.046f }, { 0.0f, 0.0f, 0.0f }, 1.3f },
{ "Chicken1", { 0.15f, 0.21f, 0.38f }, { 0.0015f, 0.077f, 0.19f }, { 0.0f, 0.0f, 0.0f }, 1.3f },
{ "Chicken2", { 0.19f, 0.25f, 0.32f }, { 0.0018f, 0.088f, 0.20f }, { 0.0f, 0.0f, 0.0f }, 1.3f },
{ "Cream", { 7.38f, 5.47f, 3.15f }, { 0.0002f, 0.0028f, 0.0163f }, { 0.0f, 0.0f, 0.0f }, 1.3f },
{ "Ketchup", { 0.18f, 0.07f, 0.03f }, { 0.061f, 0.97f, 1.45f }, { 0.0f, 0.0f, 0.0f }, 1.3f },
{ "Marble", { 2.19f, 2.62f, 3.00f }, { 0.0021f, 0.0041f, 0.0071f }, { 0.0f, 0.0f, 0.0f }, 1.5f },
{ "Potato", { 0.68f, 0.70f, 0.55f }, { 0.0024f, 0.0090f, 0.12f }, { 0.0f, 0.0f, 0.0f }, 1.3f },
{ "Skimmilk", { 0.70f, 1.22f, 1.90f }, { 0.0014f, 0.0025f, 0.0142f }, { 0.0f, 0.0f, 0.0f }, 1.3f },
{ "Skin1", { 0.74f, 0.88f, 1.01f }, { 0.032f, 0.17f, 0.48f }, { 0.0f, 0.0f, 0.0f }, 1.3f },
{ "Skin2", { 1.09f, 1.59f, 1.79f }, { 0.013f, 0.070f, 0.145f }, { 0.0f, 0.0f, 0.0f }, 1.3f },
{ "Spectralon", { 11.6f, 20.4f, 14.9f }, { 0.00f, 0.00f, 0.00f }, { 0.0f, 0.0f, 0.0f }, 1.3f },
{ "Wholemilk", { 2.55f, 3.21f, 3.77f }, { 0.0011f, 0.0024f, 0.014f }, { 0.0f, 0.0f, 0.0f }, 1.3f },
/* From "Acquiring Scattering Properties of Participating Media by Dilution"
by Narasimhan, Gupta, Donner, Ramamoorthi, Nayar, Jensen (SIGGRAPH 2006) */
{ "Lowfat Milk", { 13.1157f, 15.4445f, 17.9572f }, { 0.00287f, 0.00575f, 0.01150f }, { 0.93200f, 0.90200f, 0.85900f }, 1.33f },
{ "Reduced Milk", { 13.7335f, 15.6003f, 17.8007f }, { 0.00256f, 0.00511f, 0.01278f }, { 0.81900f, 0.79700f, 0.74600f }, 1.33f },
{ "Regular Milk", { 18.2052f, 20.3826f, 22.3698f }, { 0.00153f, 0.00460f, 0.01993f }, { 0.75000f, 0.71400f, 0.68100f }, 1.33f },
{ "Espresso", { 7.78262f, 8.13050f, 8.53875f }, { 4.79838f, 6.57512f, 8.84925f }, { 0.90700f, 0.89600f, 0.88000f }, 1.33f },
{ "Mint Mocha Coffee", { 3.51133f, 4.14383f, 5.59667f }, { 3.77200f, 5.82283f, 7.82000f }, { 0.91000f, 0.90700f, 0.91400f }, 1.33f },
{ "Lowfat Soy Milk", { 2.03838f, 2.32875f, 3.90281f }, { 0.00144f, 0.00719f, 0.03594f }, { 0.85000f, 0.85300f, 0.84200f }, 1.33f },
{ "Regular Soy Milk", { 4.66325f, 5.20183f, 8.74575f }, { 0.00192f, 0.00958f, 0.06517f }, { 0.87300f, 0.85800f, 0.83200f }, 1.33f },
{ "Lowfat Chocolate Milk", { 9.83710f, 11.4954f, 13.1629f }, { 0.01150f, 0.03680f, 0.15640f }, { 0.93400f, 0.92700f, 0.91600f }, 1.33f },
{ "Regular Chocolate Milk", { 10.5685f, 13.1416f, 15.2202f }, { 0.01006f, 0.04313f, 0.14375f }, { 0.86200f, 0.83800f, 0.80600f }, 1.33f },
{ "Coke", { 0.00254f, 0.00299f, 0.00000f }, { 0.10014f, 0.16503f, 0.24680f }, { 0.96500f, 0.97200f, 0.00000f }, 1.33f },
{ "Pepsi", { 0.00083f, 0.00203f, 0.00000f }, { 0.09164f, 0.14158f, 0.20729f }, { 0.92600f, 0.97900f, 0.00000f }, 1.33f },
{ "Sprite", { 0.00011f, 0.00014f, 0.00014f }, { 0.00189f, 0.00183f, 0.00200f }, { 0.94300f, 0.95300f, 0.95200f }, 1.33f },
{ "Gatorade", { 0.03668f, 0.04488f, 0.05742f }, { 0.02479f, 0.01929f, 0.00888f }, { 0.93300f, 0.93300f, 0.93500f }, 1.33f },
{ "Chardonnay", { 0.00021f, 0.00033f, 0.00048f }, { 0.01078f, 0.01186f, 0.02400f }, { 0.91400f, 0.95800f, 0.97500f }, 1.33f },
{ "White Zinfandel", { 0.00022f, 0.00033f, 0.00046f }, { 0.01207f, 0.01618f, 0.01984f }, { 0.91900f, 0.94300f, 0.97200f }, 1.33f },
{ "Merlot", { 0.00081f, 0.00000f, 0.00000f }, { 0.11632f, 0.25191f, 0.29434f }, { 0.97400f, 0.00000f, 0.00000f }, 1.33f },
{ "Budweiser Beder", { 0.00029f, 0.00055f, 0.00059f }, { 0.01149f, 0.02491f, 0.05779f }, { 0.91700f, 0.95600f, 0.98200f }, 1.33f },
{ "Coors Light Beer", { 0.00062f, 0.00127f, 0.00000f }, { 0.00616f, 0.01398f, 0.03498f }, { 0.91800f, 0.96600f, 0.00000f }, 1.33f },
{ "Clorox", { 0.02731f, 0.03302f, 0.03695f }, { 0.00335f, 0.01489f, 0.02630f }, { 0.91200f, 0.90500f, 0.89200f }, 1.33f },
{ "Apple Juice", { 0.00257f, 0.00311f, 0.00413f }, { 0.01296f, 0.02374f, 0.05218f }, { 0.94700f, 0.94900f, 0.94500f }, 1.33f },
{ "Cranberry Juice", { 0.00196f, 0.00238f, 0.00301f }, { 0.03944f, 0.09422f, 0.12426f }, { 0.94700f, 0.95100f, 0.97400f }, 1.33f },
{ "Grape Juice", { 0.00138f, 0.00000f, 0.00000f }, { 0.10404f, 0.23958f, 0.29325f }, { 0.96100f, 0.00000f, 0.00000f }, 1.33f },
{ "Ruby Grapefruit Juice", { 0.15496f, 0.15391f, 0.15995f }, { 0.08587f, 0.18314f, 0.25262f }, { 0.92900f, 0.92900f, 0.93100f }, 1.33f },
{ "White Grapefruit Juice", { 0.50499f, 0.52742f, 0.75282f }, { 0.01380f, 0.01883f, 0.05678f }, { 0.54800f, 0.54500f, 0.56500f }, 1.33f },
{ "Shampoo", { 0.00797f, 0.00874f, 0.01127f }, { 0.01411f, 0.04569f, 0.06172f }, { 0.91000f, 0.90500f, 0.92000f }, 1.33f },
{ "Strawberry Shampoo", { 0.00215f, 0.00245f, 0.00253f }, { 0.01449f, 0.05796f, 0.07582f }, { 0.92700f, 0.93500f, 0.99400f }, 1.33f },
{ "Head & Shoulders Shampoo", { 0.26747f, 0.27696f, 0.29574f }, { 0.08462f, 0.15688f, 0.20365f }, { 0.91100f, 0.89600f, 0.88400f }, 1.33f },
{ "Lemon Tea Powder", { 0.74489f, 0.83823f, 1.00158f }, { 2.42881f, 4.57573f, 7.21270f }, { 0.94600f, 0.94600f, 0.94900f }, 1.33f },
{ "Orange Juice Powder", { 0.00193f, 0.00213f, 0.00226f }, { 0.00145f, 0.00344f, 0.00786f }, { 0.91900f, 0.91800f, 0.92200f }, 1.33f },
{ "Pink Lemonade Powder", { 0.00123f, 0.00133f, 0.00131f }, { 0.00116f, 0.00237f, 0.00320f }, { 0.90200f, 0.90200f, 0.90400f }, 1.33f },
{ "Cappuccino Powder", { 12.2094f, 16.4659f, 29.2727f }, { 35.8441f, 49.5470f, 61.0844f }, { 0.84900f, 0.84300f, 0.92600f }, 1.33f },
{ "Salt Powder", { 0.13805f, 0.15677f, 0.17865f }, { 0.28415f, 0.32570f, 0.34148f }, { 0.80200f, 0.79300f, 0.82100f }, 1.33f },
{ "Sugar Powder", { 0.00282f, 0.00315f, 0.00393f }, { 0.01264f, 0.03105f, 0.05012f }, { 0.92100f, 0.91900f, 0.93100f }, 1.33f },
{ "Suisse Mocha Powder", { 30.0848f, 33.4452f, 38.7191f }, { 17.5020f, 27.0044f, 35.4334f }, { 0.90700f, 0.89400f, 0.88800f }, 1.33f },
{ "Pacific Ocean Surface Water", { 0.00180f, 0.00183f, 0.00228f }, { 0.03184f, 0.03132f, 0.03015f }, { 0.90200f, 0.82500f, 0.91400f }, 1.33f },
{ NULL, { 0.0f, 0.0f, 0.0f }, { 0.0f, 0.0f, 0.0f }, { 0.0f, 0.0f, 0.0f }, 0.0f }
};
static void lookupMaterial(const Properties &props, Spectrum &sigmaS, Spectrum &sigmaA, Spectrum &g, Float *eta = NULL) {
bool hasSigmaAS = props.hasProperty("sigmaS") || props.hasProperty("sigmaA"),
hasSigmaTAlbedo = props.hasProperty("sigmaT") || props.hasProperty("albedo"),
hasIOR = props.hasProperty("intIOR") || props.hasProperty("extIOR"),
manual = hasSigmaAS || hasSigmaTAlbedo,
hasPreset = props.hasProperty("material");
if (manual && hasPreset)
SLog(EError, "Please specify either a preset material or "
"scattering coefficients (you provided both!)");
if (props.hasProperty("densityMultiplier") || props.hasProperty("sizeMultiplier"))
SLog(EError, "The 'densityMultiplier' parameter has been deprecated and is now called 'scale'.");
if (hasSigmaAS && hasSigmaTAlbedo)
SLog(EError, "You can either specify sigmaS & sigmaA *or* "
"sigmaT & albedo, but no other combinations!");
std::string material =
boost::to_lower_copy(props.getString("material", "Skin1"));
/* Start with a preset */
bool found = false;
MaterialEntry *matEntry = materialData;
while (matEntry->name) {
if (material == boost::to_lower_copy(std::string(matEntry->name))) {
sigmaS.fromLinearRGB(
matEntry->sigmaS[0],
matEntry->sigmaS[1],
matEntry->sigmaS[2]);
sigmaA.fromLinearRGB(
matEntry->sigmaA[0],
matEntry->sigmaA[1],
matEntry->sigmaA[2]);
g.fromLinearRGB(
matEntry->g[0],
matEntry->g[1],
matEntry->g[2]);
sigmaS *= 100;
sigmaA *= 100;
if (eta)
*eta = matEntry->eta;
found = true;
break;
}
++matEntry;
}
if (!found) {
std::ostringstream oss;
oss << "Unable to find a material preset for \"" << material
<< "\"! Valid choices are:";
/* Unable to find the material preset by name -- print an error
message that lists all possible options */
for (matEntry = materialData; matEntry->name != NULL; ++matEntry) {
oss << matEntry->name;
if ((matEntry+1)->name)
oss << ", ";
}
SLog(EError, "%s", oss.str().c_str());
}
if (hasSigmaAS) {
sigmaS = props.getSpectrum("sigmaS", sigmaS);
sigmaA = props.getSpectrum("sigmaA", sigmaA);
} else if (hasSigmaTAlbedo) {
Spectrum albedo, sigmaT;
sigmaT = props.getSpectrum("sigmaT", sigmaA + sigmaS);
albedo = props.getSpectrum("albedo", sigmaS / (sigmaS + sigmaA));
sigmaS = albedo * sigmaT;
sigmaA = sigmaT - sigmaS;
}
if (props.hasProperty("g")) {
if (props.getType("g") == Properties::ESpectrum)
g = props.getSpectrum("g");
else
g = Spectrum(props.getFloat("g"));
}
if (g.min() <= -1 || g.max() >= 1)
SLog(EError, "The anisotropy parameter 'g' must be in the range (-1, 1)!");
if (eta && hasIOR) {
/* Specifies the internal index of refraction at the interface */
Float intIOR = lookupIOR(props, "intIOR", "bk7");
/* Specifies the external index of refraction at the interface */
Float extIOR = lookupIOR(props, "extIOR", "air");
if (intIOR < 0 || extIOR < 0)
SLog(EError, "The interior and exterior indices of "
"refraction must be positive!");
*eta = intIOR / extIOR;
}
Float scale = props.getFloat("scale", 1.0f);
sigmaS *= scale;
sigmaA *= scale;
std::ostringstream oss;
oss << "Medium parameters: sigmaS=" << sigmaS.toString() << ", sigmaA=" << sigmaA.toString() << ", g=" << g.average();
SLog(EDebug, "%s", oss.str().c_str());
}
MTS_NAMESPACE_END
#endif /* __MATERIAL_DATA_H */