Editing Volume rendering (section)

===Pre-integrated volume rendering===
Pre-integrated volume rendering<ref name=mhc90>Max N., Hanrahan P., Crawfis R.:  ''[http://www.sci.utah.edu/~jmk/papers/VolViz90-MAX.pdf Area and volume coherence for efficient visualization of 3D scalar functions].'' In Computer Graphics (San Diego Workshop on Volume Visualization, 1990) vol. 24, pp.&nbsp;27–33.</ref> is a method that can reduce sampling artifacts by pre-computing much of the required data. It is especially useful in hardware-accelerated applications<ref name="eke01">{{Cite book|doi = 10.1145/383507.383515|last1 = Engel|first1 = Klaus|last2 = Kraus|first2 = Martin|last3 = Ertl|first3 = Thomas| title=Proceedings of the ACM SIGGRAPH/EUROGRAPHICS workshop on Graphics hardware | chapter=High-quality pre-integrated volume rendering using hardware-accelerated pixel shading | date=2001 |isbn = 978-1581134070|pages = 9–16|citeseerx = 10.1.1.458.1814| s2cid=14409951 }}</ref><ref name=lwm04>Lum E., Wilson B., Ma K.: ''[http://www.cg.tuwien.ac.at/courses/Seminar/WS2004/papers/%5BLum2004%5D%20High-Quality%20Lighting%20and%20Efficient%20Pre-Integration%20for%20Volume%20Rendering.pdf High-Quality Lighting and Efficient Pre-Integration for Volume Rendering].'' In Eurographics/[[IEEE]] Symposium on Visualization 2004.</ref> because it improves quality without a large performance impact. Unlike most other optimizations, this does not skip voxels. Rather it reduces the number of samples needed to accurately display a region of voxels. The idea is to render the intervals between the samples instead of the samples themselves. This technique captures rapidly changing material, for example the transition from muscle to bone with much less computation.