init

src/Main.elm

@@ -0,0 +1,118 @@
+module Main exposing (main)
+
+import Html exposing (..)
+import Html.Attributes exposing (srcdoc)
+import Playground as P exposing (..)
+import Tuple exposing (first, second)
+
+
+type alias Memory =
+    { dx : Number
+    }
+
+
+type alias Bounds =
+    { ymin : Number
+    , ymax : Number
+    , xmin : Number
+    , xmax : Number
+    }
+
+
+type alias Coords =
+    ( Number, Number )
+
+
+init : Memory
+init =
+    { dx = 100
+    }
+
+
+main = game
+
+
+game =
+    P.game view update init
+
+
+view : Computer -> Memory -> List Shape
+view computer memory =
+    let
+        bounds =
+            { ymin = 0
+            , ymax = 511
+            , xmin = 0
+            , xmax = 511 * computer.screen.width / computer.screen.height
+            }
+
+        at =
+            placeAtCoords computer bounds
+
+        fx x =
+            (x - (bounds.xmax - bounds.xmin) / 2) ^ 2 / 1000
+    in
+    List.append
+        [ P.words purple "Welcome to my math project! Use arrow keys to adjust the width of each rectangle."
+            |> at ( (bounds.xmax - bounds.xmin) / 2, bounds.ymax - 10 )
+        , P.words purple "The current equation is y=0.25x^2."
+            |> at ( (bounds.xmax - bounds.xmin) / 2, bounds.ymax - 20 )
+        , P.words purple ("The current dx is " ++ (String.fromInt <| truncate memory.dx))
+            |> at ( (bounds.xmax - bounds.xmin) / 2, bounds.ymax - 30 )
+        , P.square purple 10
+            |> at ( 100, 100 )
+        ]
+    <|
+        makeRectangles at fx bounds memory []
+
+
+makeRectangles : (Coords -> Shape -> Shape) -> (Number -> Number) -> Bounds -> Memory -> List Shape -> List Shape
+makeRectangles at fx bounds memory prev =
+    let
+        height =
+            fx <| toFloat (List.length prev + 1) * memory.dx
+
+        numOfRecs =
+            1 + (truncate <| toFloat (List.length prev) * memory.dx)
+
+        newRec =
+            rectangle red memory.dx height
+                |> at ( memory.dx / 4 + memory.dx * toFloat (List.length prev) / 2, height / 4 )
+    in
+    if toFloat (List.length prev) <= 1 + 2 * (bounds.xmax - bounds.xmin) / memory.dx then
+        makeRectangles at fx bounds memory <|
+            List.append prev [ newRec ]
+
+    else
+        prev
+
+
+update : Computer -> Memory -> Memory
+update computer memory =
+    { memory
+        | dx = memory.dx + 0.2 * toX computer.keyboard
+    }
+
+
+placeAtScreen : Computer -> Coords -> Shape -> Shape
+placeAtScreen computer coords shape =
+    let
+        x =
+            first coords
+
+        y =
+            second coords
+    in
+    shape |> P.move (-computer.screen.width / 2 + x) (-computer.screen.height / 2 + y)
+
+
+placeAtCoords : Computer -> Bounds -> Coords -> Shape -> Shape
+placeAtCoords computer bounds coords shape =
+    let
+        x =
+            first coords
+
+        y =
+            second coords
+    in
+    placeAtScreen computer ( x / (bounds.xmax - bounds.xmin) * computer.screen.width, y / (bounds.ymax - bounds.ymin) * computer.screen.height ) shape

src/elm.json

@@ -0,0 +1,26 @@
+{
+    "type": "application",
+    "source-directories": [
+        "."
+    ],
+    "elm-version": "0.19.1",
+    "dependencies": {
+        "direct": {
+            "elm/browser": "1.0.2",
+            "elm/core": "1.0.5",
+            "elm/html": "1.0.0",
+            "evancz/elm-playground": "1.0.3"
+        },
+        "indirect": {
+            "elm/json": "1.1.3",
+            "elm/svg": "1.0.1",
+            "elm/time": "1.0.0",
+            "elm/url": "1.0.0",
+            "elm/virtual-dom": "1.0.3"
+        }
+    },
+    "test-dependencies": {
+        "direct": {},
+        "indirect": {}
+    }
+}

src/elm2nix/elm-srcs.nix

@@ -0,0 +1,47 @@
+{
+
+      "elm/browser" = {
+        sha256 = "0nagb9ajacxbbg985r4k9h0jadqpp0gp84nm94kcgbr5sf8i9x13";
+        version = "1.0.2";
+      };
+
+      "elm/core" = {
+        sha256 = "19w0iisdd66ywjayyga4kv2p1v9rxzqjaxhckp8ni6n8i0fb2dvf";
+        version = "1.0.5";
+      };
+
+      "elm/html" = {
+        sha256 = "1n3gpzmpqqdsldys4ipgyl1zacn0kbpc3g4v3hdpiyfjlgh8bf3k";
+        version = "1.0.0";
+      };
+
+      "evancz/elm-playground" = {
+        sha256 = "197igis4swjppr0dly1sx6d0hxbn56vl4gs83pwahslxx6rnw45z";
+        version = "1.0.3";
+      };
+
+      "elm/json" = {
+        sha256 = "0kjwrz195z84kwywaxhhlnpl3p251qlbm5iz6byd6jky2crmyqyh";
+        version = "1.1.3";
+      };
+
+      "elm/svg" = {
+        sha256 = "1cwcj73p61q45wqwgqvrvz3aypjyy3fw732xyxdyj6s256hwkn0k";
+        version = "1.0.1";
+      };
+
+      "elm/time" = {
+        sha256 = "0vch7i86vn0x8b850w1p69vplll1bnbkp8s383z7pinyg94cm2z1";
+        version = "1.0.0";
+      };
+
+      "elm/url" = {
+        sha256 = "0av8x5syid40sgpl5vd7pry2rq0q4pga28b4yykn9gd9v12rs3l4";
+        version = "1.0.0";
+      };
+
+      "elm/virtual-dom" = {
+        sha256 = "1yvb8px2z62xd578ag2q0r5hd1vkz9y7dfkx05355iiy1d7jwq4v";
+        version = "1.0.3";
+      };
+}

src/init.js

@@ -0,0 +1 @@
+app = Elm.Main.init();