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C-/C++-Quelltext

sf::Color Renderer::colorAt(const sf::Vector3f& position, const sf::Vector3f& direction, unsigned int reflectionTimes)
{
    float nearestDistance = 100.0f;
    RenderObject* nearestObject = nullptr;
    sf::Vector3f nearestPoint = position;
    sf::Vector2f nearestUVCoordinates = sf::Vector2f(0.0f, 0.0f);
    for(std::vector<RenderObject*>::iterator itRenderObjects(renderObjects.begin()), itEnd(renderObjects.end());
        itRenderObjects!=itEnd;
        ++itRenderObjects)
    {
        sf::Vector3f curPoint;
        sf::Vector2f curUVCoordinates;
        int outside = (*itRenderObjects)->testRay(position, direction, curPoint, curUVCoordinates);
        if(outside>0)
        {
            float curDistance = length(curPoint - position);
            if(curDistance < nearestDistance)
            {
                nearestDistance = curDistance;
                nearestObject = *itRenderObjects;
                nearestPoint = curPoint;
                nearestUVCoordinates = curUVCoordinates;
            }
        }
    }
    sf::Color color = backgroundColor;
    if(nearestObject != nullptr)
    {
        sf::Vector3f normal = nearestObject->getNormal(nearestPoint);
        sf::Vector3f directionToLight = normalize(lightPos-nearestPoint);
        color = nearestObject->getMaterial().getColorByTexture(nearestUVCoordinates);
        bool lighten = true;
        for(std::vector<RenderObject*>::iterator itRenderObjects(renderObjects.begin()), itEnd(renderObjects.end());
            itRenderObjects!=itEnd;
            ++itRenderObjects)
        {
            sf::Vector3f curPoint;
            sf::Vector2f curUVCoordinates;
            int outside = (*itRenderObjects)->testRay(nearestPoint + 0.00001f * normal , directionToLight, curPoint, curUVCoordinates);
            if(outside>0 && length(curPoint - nearestPoint) < length(lightPos - nearestPoint))
            {
                color = sf::Color::Black;
                lighten = false;
                break;
            }
        }
        if(lighten)
        {
            float dotProduct = dot(normal, directionToLight);
            if(dotProduct>0)
            {
                color = sf::Color(static_cast<sf::Uint8>(color.r * dotProduct), 
                                  static_cast<sf::Uint8>(color.g * dotProduct),
                                  static_cast<sf::Uint8>(color.b * dotProduct));
            }
            else
            {
                color = sf::Color::Black;
            }
            float refl = nearestObject->getMaterial().reflection;
            if(refl>0)
            {
                if(reflectionTimes>0)
                {
                    reflectionTimes--;
                    sf::Vector3f reflected = direction - 2.0f * dot(direction, normal) * normal;
                    sf::Color reflectedColor = colorAt(nearestPoint, reflected, reflectionTimes);
                    color += sf::Color(static_cast<sf::Uint8>(refl * reflectedColor.r),
                                   static_cast<sf::Uint8>(refl * reflectedColor.g),
                                   static_cast<sf::Uint8>(refl * reflectedColor.b));
                }
            }
        }
    }
    return color;
}

void Renderer::render()
{
    sf::Image image;
    image.create(800, 600);
    for(unsigned int y = 0; y < window.getSize().y; ++y)
    {
        for(unsigned int x = 0; x < window.getSize().x; ++x)
        {
            sf::Vector3f curDirection = normalize(sf::Vector3f(x-window.getSize().x/2.0f, window.getSize().y/2.0f-y, 400.0f));
            sf::Color pixelColor = colorAt(position, curDirection, 3);
            image.setPixel(x, y, pixelColor);
        }
    }
    renderResult.loadFromImage(image);
    window.draw(sf::Sprite(renderResult));
}