This program will generate the coordinates of a 3D Bresenham's raster line between two given points.
A very useful application of this algorithm can be found in the implementation of Fischer's Bresenham interpolation method in my another program that can rotate three dimensional image volume with an affine matrix:
Usage: [X Y Z] = bresenham_line3d(P1, P2);
P1 - vector for Point1, where P1 = [x1 y1 z1]
P2 - vector for Point2, where P2 = [x2 y2 z2]
precision (optional) - Although according to Bresenham's line algorithm, point coordinates x1 y1 z1 and x2 y2 z2 should be integer numbers, this program extends its limit to all real numbers. If any of them are floating numbers, you should specify how many digits of decimal that you would like to preserve. Be aware that the length of output X Y Z coordinates will increase in 10 times for each decimal digit that you want to preserve. By default, the precision is 0, which means that they will be rounded to the nearest integer.
X - a set of x coordinates on Bresenham's line
Y - a set of y coordinates on Bresenham's line
Z - a set of z coordinates on Bresenham's line
Therefore, all points in XYZ set (i.e. P(i) = [X(i) Y(i) Z(i)]) will constitute the Bresenham's line between P1 and P1.
P1 = [12 37 6]; P2 = [46 3 35];
[X Y Z] = bresenham_line3d(P1, P2);
This program is ported to MATLAB from:
B.Pendleton. line3d - 3D Bresenham's (a 3D line drawing algorithm), 1992.
Which is also referenced by:
Fischer, J., A. del Rio (2004). A Fast Method for Applying Rigid Transformations to Volume Data, WSCG2004 Conference.
How to modify the code in order to use it with non cubic voxel?
Using real valued input coordinates (yes, there are applications for that) results in an infinite loop. Apart from that it works well. Good job!
Real numbers can now be used, since you can specify how many digits of decimal you want to preserve. Be aware that length of output coordinate will increase in 10 times for each digit. It is 0 by default, means everything will be rounded to integer.
According to Bresenham's line algorithm, two input points' coordinates should be integer. The program now rounds up any float input coordinates to the nearest integer to prevent the infinite loop.