public Color getRadiance(ShadingState state) { if (!state.includeLights) return Color.BLACK; state.faceforward(); // emit constant radiance return state.isBehind() ? Color.BLACK : radiance; }
public Color GetRadiance(ShadingState state) { if (!state.includeSpecular) return Color.BLACK; Vector3 reflDir = new Vector3(); Vector3 refrDir = new Vector3(); state.faceforward(); float cos = state.getCosND(); bool inside = state.isBehind(); float neta = inside ? eta : 1.0f / eta; float dn = 2 * cos; reflDir.x = (dn * state.getNormal().x) + state.getRay().getDirection().x; reflDir.y = (dn * state.getNormal().y) + state.getRay().getDirection().y; reflDir.z = (dn * state.getNormal().z) + state.getRay().getDirection().z; // refracted ray float arg = 1 - (neta * neta * (1 - (cos * cos))); bool tir = arg < 0; if (tir) refrDir.x = refrDir.y = refrDir.z = 0; else { float nK = (neta * cos) - (float)Math.Sqrt(arg); refrDir.x = (neta * state.getRay().dx) + (nK * state.getNormal().x); refrDir.y = (neta * state.getRay().dy) + (nK * state.getNormal().y); refrDir.z = (neta * state.getRay().dz) + (nK * state.getNormal().z); } // compute Fresnel terms float cosTheta1 = Vector3.dot(state.getNormal(), reflDir); float cosTheta2 = -Vector3.dot(state.getNormal(), refrDir); float pPara = (cosTheta1 - eta * cosTheta2) / (cosTheta1 + eta * cosTheta2); float pPerp = (eta * cosTheta1 - cosTheta2) / (eta * cosTheta1 + cosTheta2); float kr = 0.5f * (pPara * pPara + pPerp * pPerp); float kt = 1 - kr; Color absorption = null; if (inside && absorptionDistance > 0) { // this ray is inside the object and leaving it // compute attenuation that occured along the ray absorption = Color.mul(-state.getRay().getMax() / absorptionDistance, absorptionColor.copy().opposite()).exp(); if (absorption.isBlack()) return Color.BLACK; // nothing goes through } // refracted ray Color ret = Color.black(); if (!tir) { ret.madd(kt, state.traceRefraction(new Ray(state.getPoint(), refrDir), 0)).mul(color); } if (!inside || tir) ret.add(Color.mul(kr, state.traceReflection(new Ray(state.getPoint(), reflDir), 0)).mul(color)); return absorption != null ? ret.mul(absorption) : ret; }
public Color getRadiance(ShadingState state) { if (!state.includeLights) { return(Color.BLACK); } state.faceforward(); // emit constant radiance return(state.isBehind() ? Color.BLACK : radiance); }
public void ScatterPhoton(ShadingState state, Color power) { Color refr = Color.mul(1 - f0, color); Color refl = Color.mul(f0, color); float avgR = refl.getAverage(); float avgT = refr.getAverage(); double rnd = state.getRandom(0, 0, 1); if (rnd < avgR) { state.faceforward(); // don't reflect internally if (state.isBehind()) return; // photon is reflected float cos = state.getCosND(); power.mul(refl).mul(1.0f / avgR); float dn = 2 * cos; Vector3 dir = new Vector3(); dir.x = (dn * state.getNormal().x) + state.getRay().getDirection().x; dir.y = (dn * state.getNormal().y) + state.getRay().getDirection().y; dir.z = (dn * state.getNormal().z) + state.getRay().getDirection().z; state.traceReflectionPhoton(new Ray(state.getPoint(), dir), power); } else if (rnd < avgR + avgT) { state.faceforward(); // photon is refracted float cos = state.getCosND(); float neta = state.isBehind() ? eta : 1.0f / eta; power.mul(refr).mul(1.0f / avgT); float wK = -neta; float arg = 1 - (neta * neta * (1 - (cos * cos))); Vector3 dir = new Vector3(); if (state.isBehind() && absorptionDistance > 0) { // this ray is inside the object and leaving it // compute attenuation that occured along the ray power.mul(Color.mul(-state.getRay().getMax() / absorptionDistance, absorptionColor.copy().opposite()).exp()); } if (arg < 0) { // TIR float dn = 2 * cos; dir.x = (dn * state.getNormal().x) + state.getRay().getDirection().x; dir.y = (dn * state.getNormal().y) + state.getRay().getDirection().y; dir.z = (dn * state.getNormal().z) + state.getRay().getDirection().z; state.traceReflectionPhoton(new Ray(state.getPoint(), dir), power); } else { float nK = (neta * cos) - (float)Math.Sqrt(arg); dir.x = (-wK * state.getRay().dx) + (nK * state.getNormal().x); dir.y = (-wK * state.getRay().dy) + (nK * state.getNormal().y); dir.z = (-wK * state.getRay().dz) + (nK * state.getNormal().z); state.traceRefractionPhoton(new Ray(state.getPoint(), dir), power); } } }
public Color GetRadiance(ShadingState state) { if (!state.includeSpecular) { return(Color.BLACK); } Vector3 reflDir = new Vector3(); Vector3 refrDir = new Vector3(); state.faceforward(); float cos = state.getCosND(); bool inside = state.isBehind(); float neta = inside ? eta : 1.0f / eta; float dn = 2 * cos; reflDir.x = (dn * state.getNormal().x) + state.getRay().getDirection().x; reflDir.y = (dn * state.getNormal().y) + state.getRay().getDirection().y; reflDir.z = (dn * state.getNormal().z) + state.getRay().getDirection().z; // refracted ray float arg = 1 - (neta * neta * (1 - (cos * cos))); bool tir = arg < 0; if (tir) { refrDir.x = refrDir.y = refrDir.z = 0; } else { float nK = (neta * cos) - (float)Math.Sqrt(arg); refrDir.x = (neta * state.getRay().dx) + (nK * state.getNormal().x); refrDir.y = (neta * state.getRay().dy) + (nK * state.getNormal().y); refrDir.z = (neta * state.getRay().dz) + (nK * state.getNormal().z); } // compute Fresnel terms float cosTheta1 = Vector3.dot(state.getNormal(), reflDir); float cosTheta2 = -Vector3.dot(state.getNormal(), refrDir); float pPara = (cosTheta1 - eta * cosTheta2) / (cosTheta1 + eta * cosTheta2); float pPerp = (eta * cosTheta1 - cosTheta2) / (eta * cosTheta1 + cosTheta2); float kr = 0.5f * (pPara * pPara + pPerp * pPerp); float kt = 1 - kr; Color absorption = null; if (inside && absorptionDistance > 0) { // this ray is inside the object and leaving it // compute attenuation that occured along the ray absorption = Color.mul(-state.getRay().getMax() / absorptionDistance, absorptionColor.copy().opposite()).exp(); if (absorption.isBlack()) { return(Color.BLACK); // nothing goes through } } // refracted ray Color ret = Color.black(); if (!tir) { ret.madd(kt, state.traceRefraction(new Ray(state.getPoint(), refrDir), 0)).mul(color); } if (!inside || tir) { ret.add(Color.mul(kr, state.traceReflection(new Ray(state.getPoint(), reflDir), 0)).mul(color)); } return(absorption != null?ret.mul(absorption) : ret); }
public void ScatterPhoton(ShadingState state, Color power) { Color refr = Color.mul(1 - f0, color); Color refl = Color.mul(f0, color); float avgR = refl.getAverage(); float avgT = refr.getAverage(); double rnd = state.getRandom(0, 0, 1); if (rnd < avgR) { state.faceforward(); // don't reflect internally if (state.isBehind()) { return; } // photon is reflected float cos = state.getCosND(); power.mul(refl).mul(1.0f / avgR); float dn = 2 * cos; Vector3 dir = new Vector3(); dir.x = (dn * state.getNormal().x) + state.getRay().getDirection().x; dir.y = (dn * state.getNormal().y) + state.getRay().getDirection().y; dir.z = (dn * state.getNormal().z) + state.getRay().getDirection().z; state.traceReflectionPhoton(new Ray(state.getPoint(), dir), power); } else if (rnd < avgR + avgT) { state.faceforward(); // photon is refracted float cos = state.getCosND(); float neta = state.isBehind() ? eta : 1.0f / eta; power.mul(refr).mul(1.0f / avgT); float wK = -neta; float arg = 1 - (neta * neta * (1 - (cos * cos))); Vector3 dir = new Vector3(); if (state.isBehind() && absorptionDistance > 0) { // this ray is inside the object and leaving it // compute attenuation that occured along the ray power.mul(Color.mul(-state.getRay().getMax() / absorptionDistance, absorptionColor.copy().opposite()).exp()); } if (arg < 0) { // TIR float dn = 2 * cos; dir.x = (dn * state.getNormal().x) + state.getRay().getDirection().x; dir.y = (dn * state.getNormal().y) + state.getRay().getDirection().y; dir.z = (dn * state.getNormal().z) + state.getRay().getDirection().z; state.traceReflectionPhoton(new Ray(state.getPoint(), dir), power); } else { float nK = (neta * cos) - (float)Math.Sqrt(arg); dir.x = (-wK * state.getRay().dx) + (nK * state.getNormal().x); dir.y = (-wK * state.getRay().dy) + (nK * state.getNormal().y); dir.z = (-wK * state.getRay().dz) + (nK * state.getNormal().z); state.traceRefractionPhoton(new Ray(state.getPoint(), dir), power); } } }