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2) Intersections</a></li><liclass="breadcrumb-nav-list-item"><span>Ray Triangle Intersection</span></li></ol></nav><divid="main-content"class="main-content"role="main"><h1id="ray-triangle-intersection"><ahref="#ray-triangle-intersection"class="anchor-heading"aria-labelledby="ray-triangle-intersection"><svgviewBox="0 0 16 16"aria-hidden="true"><usexlink:href="#svg-link"></use></svg></a> Ray Triangle Intersection </h1><p>We recommend that you implement the <em>Moller-Trumbore algorithm</em>, a fast algorithm that takes advantage of a barycentric coordinates parameterization of the intersection point, for ray-triangle intersection.</p><center><imgsrc="triangle_intersect_diagram.png"style="height:320px"/></center><center><imgsrc="triangle_intersect_eqns.png"style="height:400px"/></center><p>A few final notes and thoughts:</p><p>If the denominator <em>dot((e1 x d), e2)</em> is zero, what does that mean about the relationship of the ray and the triangle? Can a triangle with this area be hit by a ray? Given <em>u</em> and <em>v</em>, how do you know if the ray hits the triangle? Don’t forget that the intersection point on the ray should be within the ray’s <codeclass="language-plaintext highlighter-rouge">time_bound</code>.</p></div></div><divclass="search-overlay"></div></div></body></html>
