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Added Matrix * Tuple4 operations

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neviyn 2020-11-08 20:52:54 +00:00
parent d85e2e7426
commit b27ff44e1c
1 changed files with 23 additions and 3 deletions
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src/matrix.nim
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@ -1,5 +1,5 @@
import strformat
from "./tuple" import `=~`
from "./tuple" import `=~`, Tuple4, tuple4
type
Matrix* = object
@ -10,6 +10,7 @@ type
MatrixMultiplicationException = object of CatchableError
IdentityMatrixCreationError = object of CatchableError
MatrixInversionError = object of CatchableError
MatrixConversionError = object of CatchableError
proc matrix(width, height: int): Matrix =
result.matrix = newSeq[float](width * height)
@ -23,9 +24,19 @@ proc matrix*(data: seq[float], width, height: int): Matrix =
result.width = width
result.height = height
proc matrix*(input: Tuple4): Matrix =
result.matrix = @[input.x, input.y, input.z, input.w]
result.width = 1
result.height = 4
template `[]`*(mat: Matrix, row, column: int): float = mat.matrix[row * mat.width + column]
template `[]=`*(mat: var Matrix, row, column: int, val: float) = mat.matrix[row * mat.width + column] = val
proc toTuple4(i: Matrix): Tuple4 =
if(i.width != 1 or i.height != 4):
raise newException(MatrixConversionError, "Matrix is of incorrect dimensions to convert to a Tuple4")
return tuple4(i[0,0], i[0,1], i[0,2], i[0,3])
proc `==`*(lhs, rhs: Matrix): bool =
if lhs.width != rhs.width or lhs.height != rhs.height: return false
for i in 0..<len(lhs.matrix):
@ -46,6 +57,8 @@ proc `*`*(lhs, rhs: Matrix): Matrix =
collect += lhs[row, i] * rhs[i, col]
result[row, col] = collect
proc `*`*(lhs: Matrix, rhs: Tuple4): Tuple4 = (lhs * matrix(rhs)).toTuple4()
template isSquare(mat: Matrix): bool = mat.height == mat.width and len(mat.matrix) == (mat.height * mat.width)
proc identity(size: int): Matrix =
@ -161,6 +174,11 @@ when isMainModule:
let result = matrix(@[83.0, 63.0, 37.0, 75.0], 4, 1)
check(mat1 * mat2 == result)
test "Matrix multiplied by Tuple4":
let mat = matrix(@[1.0, 2.0, 3.0, 4.0, 2.0, 4.0, 4.0, 2.0, 8.0, 6.0, 4.0, 1.0, 0.0, 0.0, 0.0, 1.0], 4, 4)
let tup = tuple4(1.0, 2.0, 3.0, 1.0)
check(mat * tup == tuple4(18.0, 24.0, 33.0, 1.0))
test "Identity matrix creation":
check(identity(3) == matrix(@[1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0], 3, 3))
check(identity(4) == matrix(@[1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 0.0, 1.0], 4, 4))
@ -168,8 +186,10 @@ when isMainModule:
test "Identity matrix multiplication":
let mat1 = matrix(@[0.0, 1.0, 2.0, 4.0, 1.0, 2.0, 4.0, 8.0, 2.0, 4.0, 8.0, 16.0, 4.0, 8.0, 16.0, 32.0], 4, 4)
check(mat1 * mat1.identity == mat1)
let mat2 = matrix(@[1.0, 2.0, 3.0, 4.0], 4, 1)
check(mat2 * mat1.identity == mat2)
test "Tuple4 identity matrix multiplication":
let tup = tuple4(1.0, 2.0, 3.0, 4.0)
check(identity(4) * tup == tup)
test "Matrix transposition":
let mat1 = matrix(@[0.0, 9.0, 3.0, 0.0, 9.0, 8.0, 0.0, 8.0, 1.0, 8.0, 5.0, 3.0, 0.0, 0.0, 5.0, 8.0], 4, 4)