swap to nix and working version with multiple faded triangles

README.md

@@ -1 +1,31 @@
 # image-triangles
+
+make sure you have nix installed
+```
+curl https://nixos.org/nix/install | sh
+```
+
+to build:
+```
+nix-build
+
+```
+run with
+```
+./result/bin/image-triangles -o output.svg
+```
+
+to develop on:
+```
+cabal --enable-nix build
+```
+or
+```
+echo "nix: True" >> ~/.cabal/config
+cabal build
+```
+
+run with
+```
+./dist/build/image-triangles/image-triangles -o output.svg
+```

SVGFonts.nix

@@ -0,0 +1,18 @@
+{ mkDerivation, attoparsec, base, blaze-markup, blaze-svg
+, bytestring, cereal, cereal-vector, containers, data-default-class
+, diagrams-core, diagrams-lib, directory, parsec, split, stdenv
+, text, tuple, vector, xml
+}:
+mkDerivation {
+  pname = "SVGFonts";
+  version = "1.6.0.3";
+  sha256 = "bc8f8863799070c345fdd88c065852c6434af9e802fd0171df2a3dbd37f35887";
+  enableSeparateDataOutput = true;
+  libraryHaskellDepends = [
+    attoparsec base blaze-markup blaze-svg bytestring cereal
+    cereal-vector containers data-default-class diagrams-core
+    diagrams-lib directory parsec split text tuple vector xml
+  ];
+  description = "Fonts from the SVG-Font format";
+  license = stdenv.lib.licenses.bsd3;
+}

image-triangles.cabal

@@ -0,0 +1,66 @@
+-- Initial image-triangles.cabal generated by cabal init.  For further
+-- documentation, see http://haskell.org/cabal/users-guide/
+
+-- The name of the package.
+name:                image-triangles
+
+-- The package version.  See the Haskell package versioning policy (PVP)
+-- for standards guiding when and how versions should be incremented.
+-- https://wiki.haskell.org/Package_versioning_policy
+-- PVP summary:      +-+------- breaking API changes
+--                   | | +----- non-breaking API additions
+--                   | | | +--- code changes with no API change
+version:             0.1.0.0
+
+-- A short (one-line) description of the package.
+-- synopsis:
+
+-- A longer description of the package.
+-- description:
+
+-- The license under which the package is released.
+license:             BSD3
+
+-- The file containing the license text.
+license-file:        LICENSE
+
+-- The package author(s).
+author:              Jack Wines
+
+-- An email address to which users can send suggestions, bug reports, and
+-- patches.
+maintainer:          jackwines@mac.com
+
+-- A copyright notice.
+-- copyright:
+
+-- category:
+
+build-type:          Simple
+
+-- Extra files to be distributed with the package, such as examples or a
+-- README.
+extra-source-files:  CHANGELOG.md, README.md
+
+-- Constraint on the version of Cabal needed to build this package.
+cabal-version:       >=1.10
+
+
+executable image-triangles
+  -- .hs or .lhs file containing the Main module.
+  main-is:             Main.hs
+
+  -- Modules included in this executable, other than Main.
+  -- other-modules:
+
+  -- LANGUAGE extensions used by modules in this package.
+  other-extensions:    TupleSections
+
+  -- Other library packages from which modules are imported.
+  build-depends:       base, random, hip, colour, diagrams-lib, diagrams-svg
+
+  -- Directories containing source files.
+  hs-source-dirs:      src
+
+  -- Base language which the package is written in.
+  default-language:    Haskell2010

project.nix

@@ -0,0 +1,14 @@
+{ mkDerivation, base, colour, diagrams-lib, diagrams-svg, hip
+, random, stdenv
+}:
+mkDerivation {
+  pname = "image-triangles";
+  version = "0.1.0.0";
+  src = ./.;
+  isLibrary = false;
+  isExecutable = true;
+  executableHaskellDepends = [
+    base colour diagrams-lib diagrams-svg hip random
+  ];
+  license = stdenv.lib.licenses.bsd3;
+}

release.nix

@@ -0,0 +1,21 @@
+let
+  config = {
+    packageOverrides = pkgs: rec {
+      haskellPackages = pkgs.haskellPackages.override {
+        overrides = haskellPackagesNew: haskellPackagesOld: rec {
+          project =
+            haskellPackagesNew.callPackage ./project.nix { };
+
+          SVGFonts =
+            haskellPackagesNew.callPackage ./SVGFonts.nix { };
+        };
+      };
+    };
+  };
+
+  pkgs = import <nixpkgs> {inherit config;};
+
+in
+  { project = pkgs.haskellPackages.project;
+    
+  }

shell.nix

@@ -0,0 +1 @@
+(import ./release.nix).project.env

src/Main.hs

@@ -0,0 +1,31 @@
+module Main where
+
+import qualified Triangles as Tri
+import qualified Render    as Ren
+import Graphics.Image hiding (map)
+import System.Random
+import qualified Graphics.Image.ColorSpace as G
+import qualified Data.Colour.SRGB as C
+import Diagrams.Backend.SVG.CmdLine
+import Diagrams.Prelude
+
+
+
+genList = map mkStdGen . randoms
+
+singleTriangle image gen = reflectY . Ren.makeTriangle (Ren.toPointList dims t) $ col
+    where
+        t = Tri.getRandomTriangle gen image
+        col = Tri.getTriangleAverageRGB image $ t
+        dims = (cols image, rows image)
+
+main :: IO ()
+main = do
+    image <- readImageRGB VU "sierra.jpg"
+    gen <- getStdGen
+    print gen
+    let t = Tri.getRandomTriangle gen image
+    let col = Tri.getTriangleAverageRGB image t
+    print col
+    let dims = (cols image, rows image)
+    mainWith . mconcat . take 50 . map (singleTriangle image) . genList $ gen

src/Render.hs

@@ -3,14 +3,23 @@ module Render where
 import Diagrams.TrailLike
 
 
-
+import qualified Triangles as Tri
 import Diagrams.Prelude
 import Diagrams.Backend.SVG.CmdLine
 
 
-
 makeTriangle :: [Point V2 Double] -> Colour Double -> Diagram SVG
-makeTriangle verts col = fromVertices verts # fc col
+makeTriangle verts col = fromVertices verts # mapLoc closeLine # strokeLocLoop #fc col # lw 0 # opacity 0.2
 
 
-renderTriangle = makeTriangle (map p2 [(0.0,0.0), (0.1,0.1), (0.2,0.2)]) blue
+-- tupleFromIntegral :: (Int, Int) -> (Int, Int) -> (Double, Double)
+tupleFromIntegral (cols, rows) (a, b) = (fromIntegral a, fromIntegral b)
+-- tupleFromIntegral (cols, rows) (a, b) = ((a `divv` cols) , ((rows - b) `divv` rows))
+
+divv :: Int -> Int -> Double
+a `divv` b = (fromIntegral a) / (fromIntegral b)
+
+toPointList :: (Int, Int) -> Tri.Triangle -> [Point V2 Double]
+toPointList dims (a, b, c) = map (p2 . tupleFromIntegral dims) [a, b, c]
+
+-- renderTriangle = makeTriangle (map p2 [(0.0,0.0), (0.1,0.1), (0.2,0.2)]) blue

src/Triangles.hs

@@ -0,0 +1,77 @@
+{-# LANGUAGE TupleSections #-}
+
+-- module Triangles
+-- ( getRandomPixel
+-- , getRandomTriangle
+-- , getPointsInTriangle
+-- , getTriangleAverageRGB
+-- ) where
+
+module Triangles where
+
+import Graphics.Image hiding (map)
+import System.Random
+import qualified Data.Colour.SRGB as C
+import qualified Data.Colour as C
+import qualified Graphics.Image.ColorSpace as G
+
+type Image_ = Image VU RGB Double
+type Pixel_ = Pixel RGB Double
+type Point = (Int, Int)
+type Triangle = (Point, Point, Point)
+
+getRandomPixel :: StdGen -> Image_ -> (Int, Int)
+getRandomPixel gen image =
+    ( getCoord gen  . rows $ image
+    , getCoord gen' . cols $ image)
+    where
+        getCoord :: StdGen -> Int -> Int
+        getCoord gen = fst . (flip randomR) gen . (1,)
+
+        gen' = snd . next $ gen
+
+first3 (a : b : c : _) = (a, b, c)
+
+getRandomTriangle :: StdGen -> Image_ -> Triangle
+getRandomTriangle gen image =
+    first3
+    . map (\x -> getRandomPixel x image)
+    . iterate (snd . next) $ gen
+    
+getPointsInTriangle :: Image_ -> Triangle -> [Point]
+getPointsInTriangle image triangle
+    = filter (isPointInTriangle triangle)
+    $ (,) <$> [0..(rows image)] <*> [0..(cols image)]
+
+
+
+tosRGB' (G.PixelRGB r g b) = C.sRGB r g b
+
+blendEqually colors = C.affineCombo (zip (repeat fraction) colors) $ head colors
+    where
+        fraction = 1.0 / (fromIntegral . length $ colors)
+
+getTriangleAverageRGB :: Image_ -> Triangle -> C.Colour Double
+getTriangleAverageRGB image triangle = blendEqually . map tosRGB' $  pixels
+    where
+        nPixels :: Pixel RGB Double
+        nPixels = fromIntegral $ length pixels
+
+        pixels :: [Pixel_]
+        pixels = map (index image) points
+
+        points :: [Point]
+        points = getPointsInTriangle image triangle
+
+isPointInTriangle :: Triangle -> Point -> Bool
+isPointInTriangle (v1, v2, v3) pt = not (has_neg && has_pos)
+    where
+        d1 = sign pt v1 v2
+        d2 = sign pt v2 v3
+        d3 = sign pt v3 v1
+
+        has_neg = (d1 < 0) || (d2 < 0) || (d3 < 0)
+        has_pos = (d1 > 0) || (d2 > 0) || (d3 > 0)
+
+        sign :: Point -> Point -> Point -> Int
+        sign p1 p2 p3 = (fst p1 - fst p3) * (snd p2 - snd p3) - (fst p2 - fst p3) * (snd p1 - snd p3)