59 lines
1.3 KiB
C++
59 lines
1.3 KiB
C++
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#pragma once
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#include "Camera.hpp"
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#include "Color.hpp"
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#include "Geometry.hpp"
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#include "Point.hpp"
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class Light
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{
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public:
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ColorF32 Compute(Point& eye, Vector& normal, Material& material, Camera& camera)
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{
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// Point light intensity is a function of the falloff factors and the distance
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Vector direction = position - eye;
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direction.Normalize();
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float distance = direction.Length();
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ColorF32 totalIntensity =
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(color * intensity)
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/ (falloffConstant + (falloffLinear * distance));
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// Diffuse Light = Kr * I * (alpha + (1 - alpha) * n.d)
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float dotNormalDirection = std::max(Vector::Dot(normal, direction), 0.0f);
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float alpha = 0.2f;
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ColorF32 diffuseLight =
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material.diffuse
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* totalIntensity
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* (alpha + (1.0f - alpha) * dotNormalDirection);
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// Specular Light = Ks * I * (r.v)^sp
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Vector view = camera.position - eye;
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view.Normalize();
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Vector reflection = (normal * 2.0f * dotNormalDirection) - direction;
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float dotReflectionView = std::max(Vector::Dot(reflection, view), 0.0f);
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ColorF32 specularLight =
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material.specular
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* totalIntensity
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* powf(dotReflectionView, material.glossiness);
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// Total light is sum of all lights
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ColorF32 result = diffuseLight + specularLight;
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return result;
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}
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Point position;
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ColorF32 color;
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float intensity;
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float falloffConstant;
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float falloffLinear;
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};
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