Running the program

To build the program on a debian-based Linux distribution, run:

sudo apt install haskell-platform libghc-attoparsec-dev

ghc off2js.hs

Then, to translate a mushroom OFF model, run:

./off2js -modelName Mushroom < mushroom.off > mush.js

Explanation

Scaling method

To properly scale the triangle points within the [-0.5,0.5] unit cube, I applied a series of transformations to the points.

Butting points against first quadrant and origin, to [0,0,0], [Inf,Inf,Inf]

First, I moved the bounding box of the points to butt up against the first quadrant and the origin. I accomplished this by finding the minimum x, y, and z coordinates, then adding -1 times each minimum piecewise to each x, y, and z.

let min<Q> := minimum value of all points in the Q position

shiftUp(x) = x - minX
shiftUp(y) = y - minY
shiftUp(z) = z - minZ

Scaling the points to [0,0,0], [1,1,1]

Then, I scaled all of the points to the range [0,0,0], [1,1,1] by finding the maximum of all of the points, and multiplying all of the points by said maximum.

let max := maximum value of all points (after previous step)

scale(q) = q/max

Shifting points to [-.5,-.5,-.5], [.5,.5,.5]

Then, I shifted all of the points to the range [-.5,-.5,-.5], [.5,.5,.5] by subtracting .5 from all of the points.

shiftDown(q) = q - .5

After these transformations have been applied, all points should be in the proper range of the unit cube.

Building the Barycentric coordinates

To build the Barycentric coordinates, I simply produced a list of the points [1,0,0],[0,1,0],[0,0,1] t times, where t is the number of triangles, or (number of points)/3