The Discrete Ray-casting Algorithm. Qiang Xue Jiaoying Shi State Key Lab Of CAD&CG Zhejiang University. OUTLINES. Introduction Fundamentals to Accelerate Volume Rendering Implementation of Discrete Ray-casting Algorithm Results Conclusion. Introduction.
Qiang Xue Jiaoying Shi
State Key Lab Of CAD&CG
Property 1: Scanlines of pixels in the intermediate image are parallel to scanlines of voxels in the volume data;
Property 2: All voxels in a given voxel slice are scaled by the same factor;
Property 3: For parallel projection, every voxel slice has the same scale factor, and this factor can be chosen arbitrarily.
1、(Preprocessing) In viewpoint k=k1, compute ray segments set S=S1.
2、Composite rendered image from S.
3、If S is available to compute next frame then turn to stage 2 else to stage 1.
Ri(x,y,a)=Ri-1(x, y, a/2)Ri-1(x+a/2, y+2i-1, a/2)
where t1 denotes time needed to construct a frame from ray segments, t2 is preprocessing time required to refresh the whole ray segments table, and f2 is its refreshing rate.