update system docs to the new scribble API

docs/system.dj

@@ -12,7 +12,8 @@ These descriptions read like this:
 stroke
   thickness : number
   color : rgba
-  position : vec
+  from : vec
+  to : vec
   -> scribble
 ```
 
@@ -28,13 +29,13 @@ The argument name usually does not matter when calling the function - it is only
 
 The argument _type_ however is important.
 If you try to use a function with the wrong type of value as its argument, it will fail with an error.
-For example, consider a brush where we pass a number as `stroke`'s `color` and `position` arguments.
+For example, consider a brush where we pass a bunch of numbers into `stroke`'s arguments.
 
 ```haku
-stroke 1 1 1
+stroke 1 1 1 1
 ```
 
-This brush will fail to render, since `stroke` expects an `rgba` as its 2nd argument.
+This brush will fail to render, since `stroke` expects an `rgba` as its 2nd argument, and `vec`s as its 3rd and 4th arguments.
 
 With that said, there are several types of values in haku that can be passed into, and returned by functions.
 
@@ -454,18 +455,13 @@ Note that `and` and `or` are currently missing from this list, but are reserved
 You can implement them using regular functions as a replacement.
 
 ```haku
-boolAnd = \a, b ->
+and' = \a, b ->
-  if (a)
+  if (a) b
-    if (b) True
+  else a
-    else False
-  else False
 
-boolOr = \a, b ->
+or' = \a, b ->
-  if (a)
+  if (a) a
-    True
+  else b
-  else
-    if (b) True
-    else False
 ```
 
 
@@ -594,7 +590,8 @@ Before scribbles are drawn to the wall, colors are converted to 8-bit integers f
 This means some loss of precision will happen, which may cause issues with brushes like this one:
 
 ```haku
-stroke 128 #00000004 (vec 0 0)
+withDotter \d ->
+  stroke 128 #00000004 d.From d.To
 ```
 
 If you try to to use this brush to fill up a single spot with black, you will notice that despite all the math suggesting so, the color will end up gray instead.
@@ -716,88 +713,19 @@ join: \a, b -> flatten [a, b]
 ```
 
 
-## Shapes
-
-```haku
-toShape
-  value : _
-  -> () | shape
-```
-
-Converts the given value to a shape.
-
-- For `shape`, clones the shape that was passed in.
-- For `vec`, returns a point `shape`.
-- For anything else, returns `()`.
-
-```haku
-line
-  start : vec
-  end : vec
-  -> shape
-```
-
-Creates a line segment shape with the provided `start` and `end` points.
-
-```haku
-rect
-  position : vec
-  size : vec
-  -> shape
-
-rect
-  x : number
-  y : number
-  width : number
-  height : number
-  -> shape
-```
-
-Creates a rectangle shape with its top-left corner at `position`, with a given `size` stretching from the top-left corner.
-
-The alternative 4-argument version takes in the rectangle's X/Y coordinates, width, and height as separate arguments instead of aggregating them into a `vec`.
-
-```haku
-circle
-  center : vec
-  radius : number
-  -> shape
-
-circle
-  x : number
-  y : number
-  radius : number
-  -> shape
-```
-
-Creates a circle shape, with its center at `center`, with the provided radius.
-
-The alternative 3-argument version takes in the circle's center X/Y coordinates as separate arguments instead of aggregating them into a `vec`.
-
 ## Scribbles
 
 ```haku
 stroke
   thickness : number
   color : rgba
-  shape : shapeLike
+  from : vec
+  to : vec
   -> scribble
 ```
 
-Creates a stroke scribble, which outlines the provided shape with a stroke of the given thickness and color.
+Creates a stroke scribble, which draws a line between the two points `from` and `to`, with the provided `thickness` and `color`.
-
+The line's caps are round, to make strokes connect neatly with each other.
-Point shapes are drawn as circles, and `line` shapes have round caps at the line's endpoints.
-
-```haku
-fill
-  color : rgba
-  shape : shapeLike
-  -> scribble
-```
-
-Creates a fill scribble, which fills in the entire area of the provided shape with a solid color.
-
-Since this requires the shape to have a surface area, this does not do anything when point and `line` shapes are passed in.
 
 
 ## Reticles