c - 阴影和底纹

Question

我在网上看了很多光线追踪算法。但是，我对阴影和阴影没有清楚的了解。根据我的理解，下面的伪代码是否正确？

for each primitive 
    check for intersection
    if there is one 
         do color be half of the background color
         Ishadow = true
         break

for each ambient light in environment        
    calculate light contribution to the color

if ( Ishadow == false ) 
   for each point light 
     calculate diffuse shading
     calculate reflection direction
     calculate specular light


trace for reflection ray // (i)  
add color returned from i after multiplied by some coefficient

trace for refraction ray // (ii)
add color returned from ii after multiplied by some coefficient

return color value calculated until this point

Answer 1

您应该将阴影与正常的光线追踪路径相结合:对于每个屏幕像素，您通过场景发送一条光线，并最终确定最近的对象交点:在最近的对象交点处，您首先会读出像素颜色(该点处对象的纹理)，除了计算反射 vector 等(使用法线 vector )之外，您现在可以另外从该交点向场景中的每个光源转换一条光线:如果这些光线与其他物体相交在击中光源之前，交叉点处于阴影中，您可以相应地调整该点的最终颜色。