Depricate lerp use mix, add mod and zmod.

src/vmath.nim

@@ -385,7 +385,7 @@ proc fractional*[T: SomeFloat](v: T): T =
   result = abs(v)
   result = result - floor(result)
 
-proc lerp*[T: SomeFloat](a, b, v: T): T =
+proc mix*[T: SomeFloat](a, b, v: T): T =
   ## Interpolates value between a and b.
   ## * 0 -> a
   ## * 1 -> b
@@ -436,6 +436,10 @@ proc isNan*(x: SomeFloat): bool =
   ## Returns true if number is a NaN.
   x != 0.0 and (x != x or x * 0.5 == x)
 
+proc `zmod`*(a, b: float32): float32 =
+  ## Float point mod.
+  return a - b * floor(a/b)
+
 template lowerType(a: typed): string =
   ($type(a)).toLowerAscii()
 
@@ -688,6 +692,7 @@ genOp(`*`)
 genOp(`/`)
 genOp(`mod`)
 genOp(`div`)
+genOp(`zmod`)
 
 template genEqOp(op: untyped) =
   proc op*[T](a: var GVec2[T], b: GVec2[T]) =
@@ -800,9 +805,12 @@ proc lengthSq*[T](a: GVec4[T]): T =
 proc normalize*[T](a: GVec234[T]): type(a) =
   a / a.length
 
-proc lerp*[T: SomeFloat](a, b: GVec234[T], v: T): type(a) =
+proc mix*[T: SomeFloat](a, b: GVec234[T], v: T): type(a) =
   a * (1.0 - v) + b * v
 
+proc lerp*[V, T](a, b: V, v: T): type(a) {.deprecated: "use mix instead".} =
+  mix(a, b, v)
+
 proc dot*[T](a, b: GVec2[T]): T =
   a.x * b.x + a.y * b.y
 

tests/test.nim

@@ -54,6 +54,13 @@ block:
   doAssert lerp(-10.0, 10.0, 0.25) ~= -5.0
   doAssert lerp(-100.0, 100.0, 0.25) ~= -50.0
 
+  doAssert mix(0.0, 1.0, 0.5) ~= 0.5
+  doAssert mix(0.0, 10.0, 0.5) ~= 5.0
+  doAssert mix(0.0, 100.0, 0.5) ~= 50.0
+  doAssert mix(-1.0, 1.0, 0.25) ~= -0.5
+  doAssert mix(-10.0, 10.0, 0.25) ~= -5.0
+  doAssert mix(-100.0, 100.0, 0.25) ~= -50.0
+
   doAssert fixAngle(0.1) ~= 0.1
   doAssert fixAngle(1.1) ~= 1.1
   doAssert fixAngle(2.1) ~= 2.1
@@ -283,10 +290,6 @@ block:
   doAssert $dvec3(1.0, 2.0, 3.0) == "dvec3(1.0, 2.0, 3.0)"
   doAssert $dvec4(1.0, 2.0, 3.0, 4.0) == "dvec4(1.0, 2.0, 3.0, 4.0)"
 
-  echo vec2(1.0, 2.0)
-  echo vec3(1.0, 2.0, 3.0)
-  echo vec4(1.0, 2.0, 3.0, 4.0)
-
 block:
   # test swizzle vec
   var a = vec2(1, 2)
@@ -375,38 +378,6 @@ block:
 
   block:
     # test $ string functions
-    echo mat2(
-      1, 0,
-      0, 1
-    )
-    echo mat3(
-      1, 0, 0,
-      0, 1, 0,
-      0, 0, 1
-    )
-    echo mat4(
-      1, 0, 0, 0,
-      0, 1, 0, 0,
-      0, 0, 1, 0,
-      0, 0, 0, 1
-    )
-
-    echo dmat2(
-      1, 0,
-      0, 1
-    )
-    echo dmat3(
-      1, 0, 0,
-      0, 1, 0,
-      0, 0, 1
-    )
-    echo dmat4(
-      1, 0, 0, 0,
-      0, 1, 0, 0,
-      0, 0, 1, 0,
-      0, 0, 0, 1
-    )
-
     doAssert $mat2(
       1, 3,
       0, 1
@@ -824,13 +795,26 @@ block:
       a = vec3(rand(2.0)-0.5, rand(2.0)-0.5, rand(2.0)-0.5).normalize()
       b = vec3(rand(2.0)-0.5, rand(2.0)-0.5, rand(2.0)-0.5).normalize()
       q = fromTwoVectors(a, b)
-    #doAssert q.mat4 * a ~= b
     doAssert dist(q.mat4 * a, b) < 1E5
 
 block:
   let mat2d = translate(vec2(10, 20)) * rotate(45.toRadians) * scale(vec2(2))
+
   let mat3d = translate(vec3(10, 20, 0)) * rotateZ(45.toRadians) * scale(vec3(2))
 
+  doAssert mat2d ~= mat3(
+    1.414213538169861, -1.414213538169861, 0.0,
+    1.414213538169861, 1.414213538169861, 0.0,
+    10.0, 20.0, 1.0
+  )
+
+  doAssert mat3d ~= mat4(
+    1.414213418960571, -1.41421365737915, 0.0, 0.0,
+    1.41421365737915, 1.414213418960571, 0.0, 0.0,
+    0.0, 0.0, 2.0, 0.0,
+    10.0, 20.0, 0.0, 1.0
+  )
+
 block:
   let
     a2 = vec2(10, -10)
@@ -848,6 +832,21 @@ block:
   doAssert max(a3, b3) == vec3(10, 10, 7)
   doAssert max(a4, b4) == vec4(10, 10, 7, -1)
 
+  doAssert mix(10f, 7, 0.75) == 7.75
+  doAssert mix(a2, b2, 0.75) == vec2(-5.0, 5.0)
+  doAssert mix(a3, b3, 0.75) == vec3(-5.0, 5.0, 1.75)
+  doAssert mix(a4, b4, 0.75) == vec4(-5.0, 5.0, 1.75, -1.25)
+
+  doAssert `mod`(1, 2) == 1
+  doAssert `mod`(vec2(12, 6), vec2(6, 12)) == vec2(0, 6)
+  doAssert `mod`(vec3(12, 6, 18), vec3(6, 12, 7)) == vec3(0, 6, 4)
+  doAssert `mod`(vec4(12, 6, 18, 16), vec4(6, 12, 7, 15)) == vec4(0, 6, 4, 1)
+
+  doAssert `zmod`(1, 2) == 1
+  doAssert `zmod`(vec2(12, 6), vec2(6, 12)) == vec2(0, 6)
+  doAssert `zmod`(vec3(12, 6, 18), vec3(6, 12, 7)) == vec3(0, 6, 4)
+  doAssert `zmod`(vec4(12, 6, 18, 16), vec4(6, 12, 7, 15)) == vec4(0, 6, 4, 1)
+
 echo "test finished successfully"
 
 block: