Initial commit.

Framework/lights/ambient_light.cpp

@@ -0,0 +1,77 @@
+// Copyright 2009-2021 Intel Corporation
+// SPDX-License-Identifier: Apache-2.0
+
+#include "light.h"
+#include <sampling.hpp>
+#include <math/linearspace3.h>
+#include "helper.hpp"
+
+namespace embree {
+    struct AmbientLight {
+        Light super; //!< inherited light fields
+
+        Vec3fa radiance; //!< RGB color and intensity of light
+    };
+
+
+    // Implementation
+    //////////////////////////////////////////////////////////////////////////////
+
+    // XXX importance sampling is only done into the positive hemisphere
+    // ==> poor support for translucent materials
+    Light_SampleRes AmbientLight_sample(const Light* super,
+                                        const Sample& dg,
+                                        const Vec2f& s) {
+        AmbientLight* self = (AmbientLight *) super;
+        Light_SampleRes res;
+
+        const Vec3fa localDir = cosineSampleHemisphere(s);
+        res.dir = frame(dg.Ns) * localDir;
+        res.pdf = cosineSampleHemispherePDF(localDir);
+        res.dist = inf;
+        res.weight = self->radiance * rcp(res.pdf);
+
+        return res;
+    }
+
+    Light_EvalRes AmbientLight_eval(const Light* super,
+                                    const Sample& dg,
+                                    const Vec3fa& dir) {
+        AmbientLight* self = (AmbientLight *) super;
+        Light_EvalRes res;
+
+        res.value = self->radiance;
+        res.dist = inf;
+        res.pdf = cosineSampleHemispherePDF(max(dot(dg.Ns, dir), 0.f));
+
+        return res;
+    }
+
+
+    void AmbientLight_Constructor(AmbientLight* self,
+                                  const Vec3fa& radiance) {
+        Light_Constructor(&self->super);
+        self->radiance = radiance;
+        //self->super.sample = GET_FUNCTION_POINTER(AmbientLight_sample);
+        //self->super.eval = GET_FUNCTION_POINTER(AmbientLight_eval);
+        self->super.type = LIGHT_AMBIENT;
+    }
+
+
+    // Exports (called from C++)
+    //////////////////////////////////////////////////////////////////////////////
+
+    //! Create an ispc-side AmbientLight object
+    extern "C" void* AmbientLight_create() {
+        AmbientLight* self = (AmbientLight *) alignedUSMMalloc(sizeof(AmbientLight), 16);
+        AmbientLight_Constructor(self, Vec3fa(1.f));
+        return self;
+    }
+
+    //! Set the parameters of an ispc-side AmbientLight object
+    extern "C" void AmbientLight_set(void* super,
+                                     const Vec3fa& radiance) {
+        AmbientLight* self = (AmbientLight *) super;
+        self->radiance = radiance;
+    }
+} // namespace embree