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Diffstat (limited to 'source/blender/render/intern/source/sunsky.c')
| -rw-r--r-- | source/blender/render/intern/source/sunsky.c | 506 |
1 files changed, 0 insertions, 506 deletions
diff --git a/source/blender/render/intern/source/sunsky.c b/source/blender/render/intern/source/sunsky.c deleted file mode 100644 index 80dd52c220c..00000000000 --- a/source/blender/render/intern/source/sunsky.c +++ /dev/null @@ -1,506 +0,0 @@ -/* - * ***** BEGIN GPL LICENSE BLOCK ***** - * - * 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. - * - * ***** END GPL LICENSE BLOCK ***** - */ - -/** \file blender/render/intern/source/sunsky.c - * \ingroup render - * - * This feature comes from Preetham paper on "A Practical Analytic Model for Daylight" - * and example code from Brian Smits, another author of that paper in - * http://www.cs.utah.edu/vissim/papers/sunsky/code/ - */ - -#include "sunsky.h" -#include "BLI_math.h" - -/** - * These macros are defined for vector operations - * */ - -/** - * compute v1 = v2 op v3 - * v1, v2 and v3 are vectors contains 3 float - * */ -#define VEC3OPV(v1, v2, op, v3) \ - { \ - v1[0] = (v2[0] op v3[0]); \ - v1[1] = (v2[1] op v3[1]); \ - v1[2] = (v2[2] op v3[2]); \ - } (void)0 - -/** - * compute v1 = v2 op f1 - * v1, v2 are vectors contains 3 float - * and f1 is a float - * */ -#define VEC3OPF(v1, v2, op, f1) \ - { \ - v1[0] = (v2[0] op(f1)); \ - v1[1] = (v2[1] op(f1)); \ - v1[2] = (v2[2] op(f1)); \ - } (void)0 - -/** - * compute v1 = f1 op v2 - * v1, v2 are vectors contains 3 float - * and f1 is a float - * */ -#define FOPVEC3(v1, f1, op, v2) \ - { \ - v1[0] = ((f1) op v2[0]); \ - v1[1] = ((f1) op v2[1]); \ - v1[2] = ((f1) op v2[2]); \ - } (void)0 - -/** - * ClipColor: - * clip a color to range [0, 1]; - * */ -void ClipColor(float c[3]) -{ - if (c[0] > 1.0f) c[0] = 1.0f; - if (c[0] < 0.0f) c[0] = 0.0f; - if (c[1] > 1.0f) c[1] = 1.0f; - if (c[1] < 0.0f) c[1] = 0.0f; - if (c[2] > 1.0f) c[2] = 1.0f; - if (c[2] < 0.0f) c[2] = 0.0f; -} - -/** - * AngleBetween: - * compute angle between to direction - * all angles are in radians - * */ -static float AngleBetween(float thetav, float phiv, float theta, float phi) -{ - float cospsi = sinf(thetav) * sinf(theta) * cosf(phi - phiv) + cosf(thetav) * cosf(theta); - - if (cospsi > 1.0f) - return 0; - if (cospsi < -1.0f) - return M_PI; - - return acosf(cospsi); -} - -/** - * DirectionToThetaPhi: - * this function convert a direction to it's theta and phi value - * parameters: - * toSun: contains direction information - * theta, phi, are return values from this conversion - * */ -static void DirectionToThetaPhi(float *toSun, float *theta, float *phi) -{ - *theta = acosf(toSun[2]); - if (fabsf(*theta) < 1e-5f) - *phi = 0; - else - *phi = atan2f(toSun[1], toSun[0]); -} - -/** - * PerezFunction: - * compute perez function value based on input parameters - */ -static float PerezFunction(struct SunSky *sunsky, const float *lam, float theta, float gamma, float lvz) -{ - float den, num; - - den = ((1 + lam[0] * expf(lam[1])) * - (1 + lam[2] * expf(lam[3] * sunsky->theta) + lam[4] * cosf(sunsky->theta) * cosf(sunsky->theta))); - - num = ((1 + lam[0] * expf(lam[1] / cosf(theta))) * - (1 + lam[2] * expf(lam[3] * gamma) + lam[4] * cosf(gamma) * cosf(gamma))); - - return(lvz * num / den); -} - -/** - * InitSunSky: - * this function compute some sun,sky parameters according to input parameters and also initiate some other sun, sky parameters - * parameters: - * sunSky, is a structure that contains information about sun, sky and atmosphere, in this function, most of its values initiated - * turb, is atmosphere turbidity - * toSun, contains sun direction - * horizon_brighness, controls the brightness of the horizon colors - * spread, controls colors spreed at horizon - * sun_brightness, controls sun's brightness - * sun_size, controls sun's size - * back_scatter, controls back scatter light - * */ -void InitSunSky(struct SunSky *sunsky, float turb, const float toSun[3], float horizon_brightness, - float spread, float sun_brightness, float sun_size, float back_scatter, - float skyblendfac, short skyblendtype, float sky_exposure, float sky_colorspace) -{ - float theta2; - float theta3; - float T; - float T2; - float chi; - - sunsky->turbidity = turb; - - sunsky->horizon_brightness = horizon_brightness; - sunsky->spread = spread; - sunsky->sun_brightness = sun_brightness; - sunsky->sun_size = sun_size; - sunsky->backscattered_light = back_scatter; - sunsky->skyblendfac = skyblendfac; - sunsky->skyblendtype = skyblendtype; - sunsky->sky_exposure = -sky_exposure; - sunsky->sky_colorspace = sky_colorspace; - - sunsky->toSun[0] = toSun[0]; - sunsky->toSun[1] = toSun[1]; - sunsky->toSun[2] = toSun[2]; - - DirectionToThetaPhi(sunsky->toSun, &sunsky->theta, &sunsky->phi); - - sunsky->sunSolidAngle = 0.25 * M_PI * 1.39 * 1.39 / (150 * 150); /* = 6.7443e-05 */ - - theta2 = sunsky->theta * sunsky->theta; - theta3 = theta2 * sunsky->theta; - T = turb; - T2 = turb * turb; - - chi = (4.0f / 9.0f - T / 120.0f) * ((float)M_PI - 2.0f * sunsky->theta); - sunsky->zenith_Y = (4.0453f * T - 4.9710f) * tanf(chi) - 0.2155f * T + 2.4192f; - sunsky->zenith_Y *= 1000; /* conversion from kcd/m^2 to cd/m^2 */ - - if (sunsky->zenith_Y <= 0) - sunsky->zenith_Y = 1e-6; - - sunsky->zenith_x = - (+0.00165f * theta3 - 0.00374f * theta2 + 0.00208f * sunsky->theta + 0.0f) * T2 + - (-0.02902f * theta3 + 0.06377f * theta2 - 0.03202f * sunsky->theta + 0.00394f) * T + - (+0.11693f * theta3 - 0.21196f * theta2 + 0.06052f * sunsky->theta + 0.25885f); - - sunsky->zenith_y = - (+0.00275f * theta3 - 0.00610f * theta2 + 0.00316f * sunsky->theta + 0.0f) * T2 + - (-0.04214f * theta3 + 0.08970f * theta2 - 0.04153f * sunsky->theta + 0.00515f) * T + - (+0.15346f * theta3 - 0.26756f * theta2 + 0.06669f * sunsky->theta + 0.26688f); - - - sunsky->perez_Y[0] = 0.17872f * T - 1.46303f; - sunsky->perez_Y[1] = -0.35540f * T + 0.42749f; - sunsky->perez_Y[2] = -0.02266f * T + 5.32505f; - sunsky->perez_Y[3] = 0.12064f * T - 2.57705f; - sunsky->perez_Y[4] = -0.06696f * T + 0.37027f; - - sunsky->perez_x[0] = -0.01925f * T - 0.25922f; - sunsky->perez_x[1] = -0.06651f * T + 0.00081f; - sunsky->perez_x[2] = -0.00041f * T + 0.21247f; - sunsky->perez_x[3] = -0.06409f * T - 0.89887f; - sunsky->perez_x[4] = -0.00325f * T + 0.04517f; - - sunsky->perez_y[0] = -0.01669f * T - 0.26078f; - sunsky->perez_y[1] = -0.09495f * T + 0.00921f; - sunsky->perez_y[2] = -0.00792f * T + 0.21023f; - sunsky->perez_y[3] = -0.04405f * T - 1.65369f; - sunsky->perez_y[4] = -0.01092f * T + 0.05291f; - - /* suggested by glome in patch [#8063] */ - sunsky->perez_Y[0] *= sunsky->horizon_brightness; - sunsky->perez_x[0] *= sunsky->horizon_brightness; - sunsky->perez_y[0] *= sunsky->horizon_brightness; - - sunsky->perez_Y[1] *= sunsky->spread; - sunsky->perez_x[1] *= sunsky->spread; - sunsky->perez_y[1] *= sunsky->spread; - - sunsky->perez_Y[2] *= sunsky->sun_brightness; - sunsky->perez_x[2] *= sunsky->sun_brightness; - sunsky->perez_y[2] *= sunsky->sun_brightness; - - sunsky->perez_Y[3] *= sunsky->sun_size; - sunsky->perez_x[3] *= sunsky->sun_size; - sunsky->perez_y[3] *= sunsky->sun_size; - - sunsky->perez_Y[4] *= sunsky->backscattered_light; - sunsky->perez_x[4] *= sunsky->backscattered_light; - sunsky->perez_y[4] *= sunsky->backscattered_light; -} - -/** - * GetSkyXYZRadiance: - * this function compute sky radiance according to a view parameters `theta' and `phi'and sunSky values - * parameters: - * sunSky, sontains sun and sky parameters - * theta, is sun's theta - * phi, is sun's phi - * color_out, is computed color that shows sky radiance in XYZ color format - * */ -void GetSkyXYZRadiance(struct SunSky *sunsky, float theta, float phi, float color_out[3]) -{ - float gamma; - float x, y, Y, X, Z; - float hfade = 1, nfade = 1; - - - if (theta > (float)M_PI_2) { - hfade = 1.0f - (theta * (float)M_1_PI - 0.5f) * 2.0f; - hfade = hfade * hfade * (3.0f - 2.0f * hfade); - theta = M_PI_2; - } - - if (sunsky->theta > (float)M_PI_2) { - if (theta <= (float)M_PI_2) { - nfade = 1.0f - (0.5f - theta * (float)M_1_PI) * 2.0f; - nfade *= 1.0f - (sunsky->theta * (float)M_1_PI - 0.5f) * 2.0f; - nfade = nfade * nfade * (3.0f - 2.0f * nfade); - } - } - - gamma = AngleBetween(theta, phi, sunsky->theta, sunsky->phi); - - /* Compute xyY values */ - x = PerezFunction(sunsky, sunsky->perez_x, theta, gamma, sunsky->zenith_x); - y = PerezFunction(sunsky, sunsky->perez_y, theta, gamma, sunsky->zenith_y); - Y = 6.666666667e-5f * nfade * hfade * PerezFunction(sunsky, sunsky->perez_Y, theta, gamma, sunsky->zenith_Y); - - if (sunsky->sky_exposure != 0.0f) - Y = 1.0 - exp(Y * sunsky->sky_exposure); - - X = (x / y) * Y; - Z = ((1 - x - y) / y) * Y; - - color_out[0] = X; - color_out[1] = Y; - color_out[2] = Z; -} - -/** - * GetSkyXYZRadiancef: - * this function compute sky radiance according to a view direction `varg' and sunSky values - * parameters: - * sunSky, sontains sun and sky parameters - * varg, shows direction - * color_out, is computed color that shows sky radiance in XYZ color format - * */ -void GetSkyXYZRadiancef(struct SunSky *sunsky, const float varg[3], float color_out[3]) -{ - float theta, phi; - float v[3]; - - normalize_v3_v3(v, varg); - - if (v[2] < 0.001f) { - v[2] = 0.001f; - normalize_v3(v); - } - - DirectionToThetaPhi(v, &theta, &phi); - GetSkyXYZRadiance(sunsky, theta, phi, color_out); -} - -/** - * ComputeAttenuatedSunlight: - * this function compute attenuated sun light based on sun's theta and atmosphere turbidity - * parameters: - * theta, is sun's theta - * turbidity: is atmosphere turbidity - * fTau: contains computed attenuated sun light - * */ -static void ComputeAttenuatedSunlight(float theta, int turbidity, float fTau[3]) -{ - float fBeta; - float fTauR, fTauA; - float m; - float fAlpha; - - int i; - float fLambda[3]; - fLambda[0] = 0.65f; - fLambda[1] = 0.57f; - fLambda[2] = 0.475f; - - fAlpha = 1.3f; - fBeta = 0.04608365822050f * turbidity - 0.04586025928522f; - - m = 1.0f / (cosf(theta) + 0.15f * powf(93.885f - theta / (float)M_PI * 180.0f, -1.253f)); - - for (i = 0; i < 3; i++) { - /* Rayleigh Scattering */ - fTauR = expf(-m * 0.008735f * powf(fLambda[i], (float)(-4.08f))); - - /* Aerosal (water + dust) attenuation */ - fTauA = exp(-m * fBeta * powf(fLambda[i], -fAlpha)); - - fTau[i] = fTauR * fTauA; - } -} - -/** - * InitAtmosphere: - * this function initiate sunSky structure with user input parameters. - * parameters: - * sunSky, contains information about sun, and in this function some atmosphere parameters will initiated - * sun_intens, shows sun intensity value - * mief, Mie scattering factor this factor currently call with 1.0 - * rayf, Rayleigh scattering factor, this factor currently call with 1.0 - * inscattf, inscatter light factor that range from 0.0 to 1.0, 0.0 means no inscatter light and 1.0 means full inscatter light - * extincf, extinction light factor that range from 0.0 to 1.0, 0.0 means no extinction and 1.0 means full extinction - * disf, is distance factor, multiplied to pixle's z value to compute each pixle's distance to camera, - * */ -void InitAtmosphere(struct SunSky *sunSky, float sun_intens, float mief, float rayf, - float inscattf, float extincf, float disf) -{ - const float pi = M_PI; - const float n = 1.003f; /* refractive index */ - const float N = 2.545e25; - const float pn = 0.035f; - const float T = 2.0f; - float fTemp, fTemp2, fTemp3, fBeta, fBetaDash; - float c = (6.544f * T - 6.51f) * 1e-17f; - float K[3] = {0.685f, 0.679f, 0.670f}; - float vBetaMieTemp[3]; - - float fLambda[3], fLambda2[3], fLambda4[3]; - float vLambda2[3]; - float vLambda4[3]; - - int i; - - sunSky->atm_SunIntensity = sun_intens; - sunSky->atm_BetaMieMultiplier = mief; - sunSky->atm_BetaRayMultiplier = rayf; - sunSky->atm_InscatteringMultiplier = inscattf; - sunSky->atm_ExtinctionMultiplier = extincf; - sunSky->atm_DistanceMultiplier = disf; - - sunSky->atm_HGg = 0.8; - - fLambda[0] = 1 / 650e-9f; - fLambda[1] = 1 / 570e-9f; - fLambda[2] = 1 / 475e-9f; - for (i = 0; i < 3; i++) { - fLambda2[i] = fLambda[i] * fLambda[i]; - fLambda4[i] = fLambda2[i] * fLambda2[i]; - } - - vLambda2[0] = fLambda2[0]; - vLambda2[1] = fLambda2[1]; - vLambda2[2] = fLambda2[2]; - - vLambda4[0] = fLambda4[0]; - vLambda4[1] = fLambda4[1]; - vLambda4[2] = fLambda4[2]; - - /* Rayleigh scattering constants. */ - fTemp = pi * pi * (n * n - 1) * (n * n - 1) * (6 + 3 * pn) / (6 - 7 * pn) / N; - fBeta = 8 * fTemp * pi / 3; - - VEC3OPF(sunSky->atm_BetaRay, vLambda4, *, fBeta); - fBetaDash = fTemp / 2; - VEC3OPF(sunSky->atm_BetaDashRay, vLambda4, *, fBetaDash); - - - /* Mie scattering constants. */ - fTemp2 = 0.434f * c * (2 * pi) * (2 * pi) * 0.5f; - VEC3OPF(sunSky->atm_BetaDashMie, vLambda2, *, fTemp2); - - fTemp3 = 0.434f * c * pi * (2 * pi) * (2 * pi); - - VEC3OPV(vBetaMieTemp, K, *, fLambda); - VEC3OPF(sunSky->atm_BetaMie, vBetaMieTemp, *, fTemp3); - -} - -/** - * AtmospherePixleShader: - * this function apply atmosphere effect on a pixle color `rgb' at distance `s' - * parameters: - * sunSky, contains information about sun parameters and user values - * view, is camera view vector - * s, is distance - * rgb, contains rendered color value for a pixle - * */ -void AtmospherePixleShader(struct SunSky *sunSky, float view[3], float s, float rgb[3]) -{ - float costheta; - float Phase_1; - float Phase_2; - float sunColor[3]; - - float E[3]; - float E1[3]; - - - float I[3]; - float fTemp; - float vTemp1[3], vTemp2[3]; - - float sunDirection[3]; - - s *= sunSky->atm_DistanceMultiplier; - - sunDirection[0] = sunSky->toSun[0]; - sunDirection[1] = sunSky->toSun[1]; - sunDirection[2] = sunSky->toSun[2]; - - costheta = dot_v3v3(view, sunDirection); /* cos(theta) */ - Phase_1 = 1 + (costheta * costheta); /* Phase_1 */ - - VEC3OPF(sunSky->atm_BetaRay, sunSky->atm_BetaRay, *, sunSky->atm_BetaRayMultiplier); - VEC3OPF(sunSky->atm_BetaMie, sunSky->atm_BetaMie, *, sunSky->atm_BetaMieMultiplier); - VEC3OPV(sunSky->atm_BetaRM, sunSky->atm_BetaRay, +, sunSky->atm_BetaMie); - - /* e^(-(beta_1 + beta_2) * s) = E1 */ - VEC3OPF(E1, sunSky->atm_BetaRM, *, -s / (float)M_LN2); - E1[0] = exp(E1[0]); - E1[1] = exp(E1[1]); - E1[2] = exp(E1[2]); - - copy_v3_v3(E, E1); - - /* Phase2(theta) = (1-g^2)/(1+g-2g*cos(theta))^(3/2) */ - fTemp = 1 + sunSky->atm_HGg - 2 * sunSky->atm_HGg * costheta; - fTemp = fTemp * sqrtf(fTemp); - Phase_2 = (1 - sunSky->atm_HGg * sunSky->atm_HGg) / fTemp; - - VEC3OPF(vTemp1, sunSky->atm_BetaDashRay, *, Phase_1); - VEC3OPF(vTemp2, sunSky->atm_BetaDashMie, *, Phase_2); - - VEC3OPV(vTemp1, vTemp1, +, vTemp2); - FOPVEC3(vTemp2, 1.0f, -, E1); - VEC3OPV(vTemp1, vTemp1, *, vTemp2); - - FOPVEC3(vTemp2, 1.0f, /, sunSky->atm_BetaRM); - - VEC3OPV(I, vTemp1, *, vTemp2); - - VEC3OPF(I, I, *, sunSky->atm_InscatteringMultiplier); - VEC3OPF(E, E, *, sunSky->atm_ExtinctionMultiplier); - - /* scale to color sun */ - ComputeAttenuatedSunlight(sunSky->theta, sunSky->turbidity, sunColor); - VEC3OPV(E, E, *, sunColor); - - VEC3OPF(I, I, *, sunSky->atm_SunIntensity); - - VEC3OPV(rgb, rgb, *, E); - VEC3OPV(rgb, rgb, +, I); -} - -#undef VEC3OPV -#undef VEC3OPF -#undef FOPVEC3 - -/* EOF */ |