Sun,Sky and atmosphere for lamps(sun type), PATCH#8063 http://projects.blender.org/tracker/?func=detail&atid=127&aid=8063&group_id=9

1 files changed, 141 insertions, 0 deletions

diff --git a/source/blender/render/intern/include/sunsky.h b/source/blender/render/intern/include/sunsky.h
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+++ b/source/blender/render/intern/include/sunsky.h
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+ /**
+ * ***** 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * Contributor(s): zaghaghi
+ * 
+ * ***** END GPL LICENSE BLOCK *****
+ */
+/**
+ * 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/
+ * */
+#ifndef SUNSKY_H_
+#define SUNSKY_H_
+
+#define SPECTRUM_MAX_COMPONENTS     100
+#define SPECTRUM_START              350.0
+#define SPECTRUM_END                800.0
+
+typedef struct SunSky
+{
+    short effect_type;
+    float turbidity;
+    float theta, phi;
+    
+    float toSun[3];
+
+    /*float sunSpectralRaddata[SPECTRUM_MAX_COMPONENTS];*/
+    float sunSolidAngle;
+
+    float zenith_Y, zenith_x, zenith_y;
+    
+    float perez_Y[5], perez_x[5], perez_y[5];
+
+    /* suggested by glome in 
+     * http://projects.blender.org/tracker/?func=detail&atid=127&aid=8063&group_id=9*/
+    float horizon_brightness;
+    float spread;
+    float sun_brightness;
+    float sun_size;
+    float backscattered_light;
+    
+    float atm_HGg;
+
+    float atm_SunIntensity;
+    float atm_InscatteringMultiplier;
+    float atm_ExtinctionMultiplier;
+    float atm_BetaRayMultiplier;
+    float atm_BetaMieMultiplier;
+    float atm_DistanceMultiplier;
+
+    float atm_BetaRay[3];
+    float atm_BetaDashRay[3];
+    float atm_BetaMie[3];
+    float atm_BetaDashMie[3];
+    float atm_BetaRM[3];
+}SunSky;
+
+/**
+ * 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 informtion 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, float *toSun, float horizon_brightness, 
+				float spread,float sun_brightness, float sun_size, float back_scatter);
+
+/**
+ * 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]);
+
+/**
+ * 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]);
+
+/**
+ * InitAtmosphere:
+ * this function intiate 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, multiplyed 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);
+
+/**
+ * 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]);
+
+/**
+ * ClipColor:
+ * clip a color to range [0,1];
+ * */
+void ClipColor(float c[3]);
+
+#endif /*SUNSKY_H_*/