rayTrace: function()

in benchmarks/JetStream2/Octane/raytrace.js [705:803]
84 lines of code
15 McCabe index (conditional complexity)

    rayTrace: function(info, ray, scene, depth){
        // Calc ambient
        var color = Flog.RayTracer.Color.prototype.multiplyScalar(info.color, scene.background.ambience);
        var oldColor = color;
        var shininess = Math.pow(10, info.shape.material.gloss + 1);

        for(var i=0; i<scene.lights.length; i++){
            var light = scene.lights[i];

            // Calc diffuse lighting
            var v = Flog.RayTracer.Vector.prototype.subtract(
                                light.position,
                                info.position
                            ).normalize();

            if(this.options.renderDiffuse){
                var L = v.dot(info.normal);
                if(L > 0.0){
                    color = Flog.RayTracer.Color.prototype.add(
                                        color,
                                        Flog.RayTracer.Color.prototype.multiply(
                                            info.color,
                                            Flog.RayTracer.Color.prototype.multiplyScalar(
                                                light.color,
                                                L
                                            )
                                        )
                                    );
                }
            }

            // The greater the depth the more accurate the colours, but
            // this is exponentially (!) expensive
            if(depth <= this.options.rayDepth){
          // calculate reflection ray
          if(this.options.renderReflections && info.shape.material.reflection > 0)
          {
              var reflectionRay = this.getReflectionRay(info.position, info.normal, ray.direction);
              var refl = this.testIntersection(reflectionRay, scene, info.shape);

              if (refl.isHit && refl.distance > 0){
                  refl.color = this.rayTrace(refl, reflectionRay, scene, depth + 1);
              } else {
                  refl.color = scene.background.color;
                        }

                  color = Flog.RayTracer.Color.prototype.blend(
                    color,
                    refl.color,
                    info.shape.material.reflection
                  );
          }

                // Refraction
                /* TODO */
            }

            /* Render shadows and highlights */

            var shadowInfo = new Flog.RayTracer.IntersectionInfo();

            if(this.options.renderShadows){
                var shadowRay = new Flog.RayTracer.Ray(info.position, v);

                shadowInfo = this.testIntersection(shadowRay, scene, info.shape);
                if(shadowInfo.isHit && shadowInfo.shape != info.shape /*&& shadowInfo.shape.type != 'PLANE'*/){
                    var vA = Flog.RayTracer.Color.prototype.multiplyScalar(color, 0.5);
                    var dB = (0.5 * Math.pow(shadowInfo.shape.material.transparency, 0.5));
                    color = Flog.RayTracer.Color.prototype.addScalar(vA,dB);
                }
            }

      // Phong specular highlights
      if(this.options.renderHighlights && !shadowInfo.isHit && info.shape.material.gloss > 0){
        var Lv = Flog.RayTracer.Vector.prototype.subtract(
                            info.shape.position,
                            light.position
                        ).normalize();

        var E = Flog.RayTracer.Vector.prototype.subtract(
                            scene.camera.position,
                            info.shape.position
                        ).normalize();

        var H = Flog.RayTracer.Vector.prototype.subtract(
                            E,
                            Lv
                        ).normalize();

        var glossWeight = Math.pow(Math.max(info.normal.dot(H), 0), shininess);
        color = Flog.RayTracer.Color.prototype.add(
                            Flog.RayTracer.Color.prototype.multiplyScalar(light.color, glossWeight),
                            color
                        );
      }
        }
        color.limit();
        return color;
    }