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add: vector/matrix modules, tests, nim config script
author Sam <sam@basx.dev>
date Wed, 28 Dec 2022 11:42:21 +0700
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children 617c6dcddbe2
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12:9e5fe647ff91 13:a571db114152
1 import std/math
2 import std/strutils
3 import std/macros
4 import std/typetraits
5 import std/tables
6
7
8 type
9 Vec2*[T: SomeNumber] = array[2, T]
10 Vec3*[T: SomeNumber] = array[3, T]
11 Vec4*[T: SomeNumber] = array[4, T]
12 Vec* = Vec2|Vec3|Vec4
13
14 # define some often used constants
15 func ConstX[T: SomeNumber](): auto {.compiletime.} = Vec3[T]([T(1), T(0), T(0)])
16 func ConstY[T: SomeNumber](): auto {.compiletime.} = Vec3[T]([T(0), T(1), T(0)])
17 func ConstZ[T: SomeNumber](): auto {.compiletime.} = Vec3[T]([T(0), T(0), T(1)])
18 func ConstR[T: SomeNumber](): auto {.compiletime.} = Vec3[T]([T(1), T(0), T(0)])
19 func ConstG[T: SomeNumber](): auto {.compiletime.} = Vec3[T]([T(0), T(1), T(0)])
20 func ConstB[T: SomeNumber](): auto {.compiletime.} = Vec3[T]([T(0), T(0), T(1)])
21
22 # generates constants: Xf, Xf32, Xf64, Xi, Xi8, Xi16, Xi32, Xi64
23 # Also for Y, Z, R, G, B
24 # not sure if this is necessary or even a good idea...
25 macro generateAllConsts() =
26 result = newStmtList()
27 for component in ["X", "Y", "Z", "R", "G", "B"]:
28 for theType in ["int", "int8", "int16", "int32", "int64", "float", "float32", "float64"]:
29 var typename = theType[0 .. 0]
30 if theType[^2].isDigit:
31 typename = typename & theType[^2]
32 if theType[^1].isDigit:
33 typename = typename & theType[^1]
34 result.add(
35 newConstStmt(
36 postfix(ident(component & typename), "*"),
37 newCall(nnkBracketExpr.newTree(ident("Const" & component), ident(theType)))
38 )
39 )
40
41 generateAllConsts()
42
43 const X* = ConstX[float]()
44 const Y* = ConstY[float]()
45 const Z* = ConstZ[float]()
46
47 func newVec2*[T](x, y: T): auto = Vec2([x, y])
48 func newVec3*[T](x, y, z: T): auto = Vec3([x, y, z])
49 func newVec4*[T](x, y, z, w: T): auto = Vec4([x, y, z, w])
50
51 func to*[T](v: Vec2): auto = Vec2([T(v[0]), T(v[1])])
52 func to*[T](v: Vec3): auto = Vec3([T(v[0]), T(v[1]), T(v[2])])
53 func to*[T](v: Vec4): auto = Vec4([T(v[0]), T(v[1]), T(v[2]), T(v[3])])
54
55 func toString[T](value: T): string =
56 var items: seq[string]
57 for item in value:
58 items.add($item)
59 $T & "(" & join(items, " ") & ")"
60
61 func `$`*(v: Vec2[SomeNumber]): string = toString[Vec2[SomeNumber]](v)
62 func `$`*(v: Vec3[SomeNumber]): string = toString[Vec3[SomeNumber]](v)
63 func `$`*(v: Vec4[SomeNumber]): string = toString[Vec4[SomeNumber]](v)
64
65 func length*(vec: Vec2[SomeFloat]): auto = sqrt(vec[0] * vec[0] + vec[1] * vec[1])
66 func length*(vec: Vec2[SomeInteger]): auto = sqrt(float(vec[0] * vec[0] + vec[1] * vec[1]))
67 func length*(vec: Vec3[SomeFloat]): auto = sqrt(vec[0] * vec[0] + vec[1] * vec[1] + vec[2] * vec[2])
68 func length*(vec: Vec3[SomeInteger]): auto = sqrt(float(vec[0] * vec[0] + vec[1] * vec[1] + vec[2] * vec[2]))
69 func length*(vec: Vec4[SomeFloat]): auto = sqrt(vec[0] * vec[0] + vec[1] * vec[1] + vec[2] * vec[2] + vec[3] * vec[3])
70 func length*(vec: Vec4[SomeInteger]): auto = sqrt(float(vec[0] * vec[0] + vec[1] * vec[1] + vec[2] * vec[2] + vec[3] * vec[3]))
71
72 func normalized*[T](vec: Vec2[T]): auto =
73 let l = vec.length
74 when T is SomeFloat:
75 Vec2[T]([vec[0] / l, vec[1] / l])
76 else:
77 Vec2[float]([float(vec[0]) / l, float(vec[1]) / l])
78 func normalized*[T](vec: Vec3[T]): auto =
79 let l = vec.length
80 when T is SomeFloat:
81 Vec3[T]([vec[0] / l, vec[1] / l, vec[2] / l])
82 else:
83 Vec3[float]([float(vec[0]) / l, float(vec[1]) / l, float(vec[2]) / l])
84 func normalized*[T](vec: Vec4[T]): auto =
85 let l = vec.length
86 when T is SomeFloat:
87 Vec4[T]([vec[0] / l, vec[1] / l, vec[2] / l, vec[3] / l])
88 else:
89 Vec4[float]([float(vec[0]) / l, float(vec[1]) / l, float(vec[2]) / l, float(vec[3]) / l])
90
91 # scalar operations
92 func `+`*(a: Vec2, b: SomeNumber): auto = Vec2([a[0] + b, a[1] + b])
93 func `+`*(a: Vec3, b: SomeNumber): auto = Vec3([a[0] + b, a[1] + b, a[2] + b])
94 func `+`*(a: Vec4, b: SomeNumber): auto = Vec4([a[0] + b, a[1] + b, a[2] + b, a[3] + b])
95 func `-`*(a: Vec2, b: SomeNumber): auto = Vec2([a[0] - b, a[1] - b])
96 func `-`*(a: Vec3, b: SomeNumber): auto = Vec3([a[0] - b, a[1] - b, a[2] - b])
97 func `-`*(a: Vec4, b: SomeNumber): auto = Vec4([a[0] - b, a[1] - b, a[2] - b, a[3] - b])
98 func `*`*(a: Vec2, b: SomeNumber): auto = Vec2([a[0] * b, a[1] * b])
99 func `*`*(a: Vec3, b: SomeNumber): auto = Vec3([a[0] * b, a[1] * b, a[2] * b])
100 func `*`*(a: Vec4, b: SomeNumber): auto = Vec4([a[0] * b, a[1] * b, a[2] * b, a[3] * b])
101 func `/`*[T: SomeInteger](a: Vec2[T], b: SomeInteger): auto = Vec2([a[0] div b, a[1] div b])
102 func `/`*[T: SomeFloat](a: Vec2[T], b: SomeFloat): auto = Vec2([a[0] / b, a[1] / b])
103 func `/`*[T: SomeInteger](a: Vec3[T], b: SomeInteger): auto = Vec3([a[0] div b, a[1] div b, a[2] div b])
104 func `/`*[T: SomeFloat](a: Vec3[T], b: SomeFloat): auto = Vec3([a[0] / b, a[1] / b, a[2] / b])
105 func `/`*[T: SomeInteger](a: Vec4[T], b: SomeInteger): auto = Vec4([a[0] div b, a[1] div b, a[2] div b, a[3] div b])
106 func `/`*[T: SomeFloat](a: Vec4[T], b: SomeFloat): auto = Vec4([a[0] / b, a[1] / b, a[2] / b, a[3] / b])
107
108 func `+`*(a: SomeNumber, b: Vec2): auto = Vec2([a + b[0], a + b[1]])
109 func `+`*(a: SomeNumber, b: Vec3): auto = Vec3([a + b[0], a + b[1], a + b[2]])
110 func `+`*(a: SomeNumber, b: Vec4): auto = Vec4([a + b[0], a + b[1], a + b[2], a + b[3]])
111 func `-`*(a: SomeNumber, b: Vec2): auto = Vec2([a - b[0], a - b[1]])
112 func `-`*(a: SomeNumber, b: Vec3): auto = Vec3([a - b[0], a - b[1], a - b[2]])
113 func `-`*(a: SomeNumber, b: Vec4): auto = Vec4([a - b[0], a - b[1], a - b[2], a - b[3]])
114 func `*`*(a: SomeNumber, b: Vec2): auto = Vec2([a * b[0], a * b[1]])
115 func `*`*(a: SomeNumber, b: Vec3): auto = Vec3([a * b[0], a * b[1], a * b[2]])
116 func `*`*(a: SomeNumber, b: Vec4): auto = Vec4([a * b[0], a * b[1], a * b[2], a * b[3]])
117 func `/`*[T: SomeInteger](a: SomeInteger, b: Vec2[T]): auto = Vec2([a div b[0], a div b[1]])
118 func `/`*[T: SomeFloat](a: SomeFloat, b: Vec2[T]): auto = Vec2([a / b[0], a / b[1]])
119 func `/`*[T: SomeInteger](a: SomeInteger, b: Vec3[T]): auto = Vec3([a div b[0], a div b[1], a div b[2]])
120 func `/`*[T: SomeFloat](a: SomeFloat, b: Vec3[T]): auto = Vec3([a / b[0], a / b[1], a / b[2]])
121 func `/`*[T: SomeInteger](a: SomeInteger, b: Vec4[T]): auto = Vec4([a div b[0], a div b[1], a div b[2], a div b[3]])
122 func `/`*[T: SomeFloat](a: SomeFloat, b: Vec4[T]): auto = Vec4([a / b[0], a / b[1], a / b[2], a / b[3]])
123
124 # compontent-wise operations
125 func `+`*(a, b: Vec2): auto = Vec2([a[0] + b[0], a[1] + b[1]])
126 func `+`*(a, b: Vec3): auto = Vec3([a[0] + b[0], a[1] + b[1], a[2] + b[2]])
127 func `+`*(a, b: Vec4): auto = Vec4([a[0] + b[0], a[1] + b[1], a[2] + b[2], a[3] + b[3]])
128 func `-`*(a: Vec2): auto = Vec2([-a[0], -a[1]])
129 func `-`*(a: Vec3): auto = Vec3([-a[0], -a[1], -a[2]])
130 func `-`*(a: Vec4): auto = Vec4([-a[0], -a[1], -a[2], -a[3]])
131 func `-`*(a, b: Vec2): auto = Vec2([a[0] - b[0], a[1] - b[1]])
132 func `-`*(a, b: Vec3): auto = Vec3([a[0] - b[0], a[1] - b[1], a[2] - b[2]])
133 func `-`*(a, b: Vec4): auto = Vec4([a[0] - b[0], a[1] - b[1], a[2] - b[2], a[3] - b[3]])
134 func `*`*(a, b: Vec2): auto = Vec2([a[0] * b[0], a[1] * b[1]])
135 func `*`*(a, b: Vec3): auto = Vec3([a[0] * b[0], a[1] * b[1], a[2] * b[2]])
136 func `*`*(a, b: Vec4): auto = Vec4([a[0] * b[0], a[1] * b[1], a[2] * b[2], a[3] * b[3]])
137 func `/`*[T: SomeInteger](a, b: Vec2[T]): auto = Vec2([a[0] div b[0], a[1] div b[1]])
138 func `/`*[T: SomeFloat](a, b: Vec2[T]): auto = Vec2([a[0] / b[0], a[1] / b[1]])
139 func `/`*[T: SomeInteger](a, b: Vec3[T]): auto = Vec3([a[0] div b[0], a[1] div b[1], a[2] div b[2]])
140 func `/`*[T: SomeFloat](a, b: Vec3[T]): auto = Vec3([a[0] / b[0], a[1] / b[1], a[2] / b[2]])
141 func `/`*[T: SomeInteger](a, b: Vec4[T]): auto = Vec4([a[0] div b[0], a[1] div b[1], a[2] div b[2], a[3] div b[3]])
142 func `/`*[T: SomeFloat](a, b: Vec4[T]): auto = Vec4([a[0] / b[0], a[1] / b[1], a[2] / b[2], a[3] / b[3]])
143
144 # special operations
145 func dot*(a, b: Vec2): auto = a[0] * b[0] + a[1] * b[1]
146 func dot*(a, b: Vec3): auto = a[0] * b[0] + a[1] * b[1] + a[2] * b[2]
147 func dot*(a, b: Vec4): auto = a[0] * b[0] + a[1] * b[1] + a[2] * b[2] + a[3] * b[3]
148 func cross*(a, b: Vec3): auto = Vec3([
149 a[1] * b[2] - a[2] * b[1],
150 a[2] * b[0] - a[0] * b[2],
151 a[0] * b[1] - a[1] * b[0],
152 ])
153
154
155 # macro to allow creation of new vectors by specifying vector components as attributes
156 # e.g. myVec.xxy will return a new Vec3 that contains the components x, x an y of the original vector
157 # (instead of x, y, z for a simple copy)
158 proc vectorAttributeAccessor(accessor: string): NimNode =
159 const ACCESSOR_INDICES = {
160 'x': 0,
161 'y': 1,
162 'z': 2,
163 'w': 3,
164 'r': 0,
165 'g': 1,
166 'b': 2,
167 'a': 3,
168 }.toTable
169 var ret: NimNode
170 let accessorvalue = accessor
171
172 if accessorvalue.len == 0:
173 raise newException(Exception, "empty attribute")
174 elif accessorvalue.len == 1:
175 ret = nnkBracket.newTree(ident("value"), newLit(ACCESSOR_INDICES[accessorvalue[0]]))
176 if accessorvalue.len > 1:
177 var attrs = nnkBracket.newTree()
178 for attrname in accessorvalue:
179 attrs.add(nnkBracketExpr.newTree(ident("value"), newLit(ACCESSOR_INDICES[attrname])))
180 ret = nnkCall.newTree(ident("Vec" & $accessorvalue.len), attrs)
181
182 newProc(
183 name=nnkPostfix.newTree(ident("*"), ident(accessor)),
184 params=[ident("auto"), nnkIdentDefs.newTree(ident("value"), ident("Vec"), newEmptyNode())],
185 body=newStmtList(ret),
186 procType = nnkFuncDef,
187 )
188
189 macro createVectorAttribAccessorFuncs() =
190 const COORD_ATTRS = ["x", "y", "z", "w"]
191 const COLOR_ATTRS = ["r", "g", "b", "a"]
192 result = nnkStmtList.newTree()
193 for attlist in [COORD_ATTRS, COLOR_ATTRS]:
194 for i in attlist:
195 result.add(vectorAttributeAccessor(i))
196 for j in attlist:
197 result.add(vectorAttributeAccessor(i & j))
198 for k in attlist:
199 result.add(vectorAttributeAccessor(i & j & k))
200 for l in attlist:
201 result.add(vectorAttributeAccessor(i & j & k & l))
202
203 createVectorAttribAccessorFuncs()