WIP

2024-11-05 06:43:37 +00:00 · 2020-08-04 08:15:06 +02:00 · 2020-08-04 08:15:06 +02:00 · c9e702e660
commit c9e702e660
22 changed files with 6491 additions and 0 deletions
--- a/.gitignore
+++ b/.gitignore
@ -0,0 +1,5 @@
+dist-newstyle/
+assets/*.svg
+assets/*/
+*.txt
+cabal.project.local
--- a/MetaBrush.cabal
+++ b/MetaBrush.cabal
@ -0,0 +1,109 @@
+cabal-version:  3.0
+name:           MetaBrush
+version:        0.1.0.0
+synopsis:       GUI for brush calligraphy.
+category:       Calligraphy, Font, Geometry, Graphics, GUI
+license:        BSD-3-Clause
+homepage:       https://gitlab.com/sheaf/MetaBrush
+build-type:     Simple
+data-files:
+  assets/theme.css
+description:
+
+  MetaBrush is a GUI for brush calligraphy based on Bézier curves.
+
+  A brush stroke is defined by two components:
+
+    * the path of the brush, specified using quadratic Bézier curves,
+
+    * the shape of the brush, also specified with quadratic Bézier curves.
+
+  The shape of the brush is allowed to vary along the path.
+
+common common
+
+    build-depends:
+        base
+          >= 4.13 && < 4.16
+
+    default-language:
+        Haskell2010
+
+    ghc-options:
+        -O1
+        -fexpose-all-unfoldings
+        -fspecialise-aggressively
+        -Wall
+        -Wcompat
+        -fwarn-missing-local-signatures
+        -fwarn-incomplete-patterns
+        -fwarn-incomplete-uni-patterns
+        -fwarn-missing-deriving-strategies
+
+library
+
+    import:
+        common
+
+    hs-source-dirs:
+        src/lib
+
+    exposed-modules:
+        Math.Bezier.Cubic
+      , Math.Bezier.Quadratic
+      , Math.Bezier.Stroke
+      , Math.Bezier.Subdivision
+      , Math.Module
+      , Math.Vector2D
+
+    build-depends:
+        acts
+          ^>= 0.3.1.0
+      , generic-data
+          >= 0.8.0.0 && < 0.8.4.0
+      , groups
+          ^>= 0.4.1.0
+      , groups-generic
+          ^>= 0.1.0.0
+
+executable MetaBrush
+
+    hs-source-dirs:
+        src/app
+      , app
+
+    main-is:
+        Main.hs
+
+    other-modules:
+        MetaBrush.Asset.Brush
+      , MetaBrush.Asset.Logo
+      , MetaBrush.Asset.Magnifier
+      , MetaBrush.Asset.Meta
+      , MetaBrush.Asset.TickBox
+      , MetaBrush.Asset.WindowIcons
+      , MetaBrush.Document
+      , MetaBrush.Render.Util
+      , MetaBrush.Stroke
+      , Paths_MetaBrush
+
+    autogen-modules:
+        Paths_MetaBrush
+
+    ghc-options:
+        -threaded -rtsopts
+
+    build-depends:
+        MetaBrush
+      , gi-gdk
+          >= 3.0.22 && < 3.1
+      , gi-glib
+          >= 2.0.23 && < 2.1
+      , gi-gtk
+          >= 3.0.35 && < 3.1
+      , gi-cairo-render
+          ^>= 0.0.1
+      , gi-cairo-connector
+          ^>= 0.0.1
+      , text
+          ^>= 1.2.3.1 && < 1.2.5
--- a/app/Main.hs
+++ b/app/Main.hs
@ -0,0 +1,91 @@
+module Main
+  ( main )
+  where
+
+-- gi-cairo-connector
+import qualified GI.Cairo.Render.Connector as Cairo
+  ( renderWithContext )
+
+-- gi-gdk
+import qualified GI.Gdk as GDK
+
+-- gi-gtk
+import qualified GI.Gtk as GTK
+
+-- MetaBrush
+import Paths_MetaBrush
+  ( getDataFileName )
+
+--------------------------------------------------------------------------------
+
+main :: IO ()
+main = do
+
+  ---------------------------------------------------------
+  -- Initialise GTK
+
+  _ <- GTK.init Nothing
+  Just screen <- GDK.screenGetDefault
+
+  themePath <- getDataFileName "theme.css"
+  cssProvider <- GTK.cssProviderNew
+  GTK.cssProviderLoadFromPath cssProvider themePath
+  GTK.styleContextAddProviderForScreen screen cssProvider 1000
+
+  window <- GTK.windowNew GTK.WindowTypeToplevel
+  windowWidgetPath <- GTK.widgetGetPath window
+  widgetAddClass window "window"
+  GTK.setWindowResizable window True
+  GTK.setWindowDecorated window False
+  GTK.setWindowTitle window "MetaBrush"
+  GTK.windowSetDefaultSize window 800 600
+
+  let
+    baseMinWidth, baseMinHeight :: Int32
+    baseMinWidth  = 320
+    baseMinHeight = 240
+
+  windowGeometry <- GDK.newZeroGeometry
+  GDK.setGeometryMinWidth  windowGeometry baseMinWidth
+  GDK.setGeometryMinHeight windowGeometry baseMinHeight
+  GTK.windowSetGeometryHints window ( Nothing @GTK.Widget )
+    ( Just windowGeometry )
+    [ GDK.WindowHintsMinSize ]
+
+  ---------------------------------------------------------
+  -- Create base UI elements
+
+  baseOverlay <- GTK.overlayNew
+  GT.setContainerChild window baseOverlay
+
+  uiGrid <- GTK.gridNew
+  GTK.overlaySetChild baseOverlay uiGrid
+
+  logo      <- GTK.boxNew GTK.OrientationVertical   0
+  titleBar  <- GTK.boxNew GTK.OrientationHorizontal 0
+  toolBar   <- GTK.boxNew GTK.OrientationVertical   0
+  fileBar   <- GTK.boxNew GTK.OrientationHorizontal 0
+  mainView  <- GTK.gridNew
+  panelGrid <- GTK.gridNew
+  infoBar   <- GTK.boxNew GTK.OrientationHorizontal 0
+
+  GTK.gridAttach uiGrid logo      0 0 1 2
+  GTK.gridAttach uiGrid titleBar  1 0 3 1
+  GTK.gridAttach uiGrid toolBar   0 2 2 2
+  GTK.gridAttach uiGrid fileBar   2 1 1 1
+  GTK.gridAttach uiGrid mainView  2 2 1 1
+  GTK.gridAttach uiGrid panelGrid 3 2 1 2
+  GTK.gridAttach uiGrid infoBar   2 3 1 1
+
+  --------------------------------------
+  -- Actions
+
+  GTK.widgetAddEvents window [GDK.EventMaskKeyPressMask, GDK.EventMaskKeyReleaseMask]
+  _ <- GTK.onWidgetKeyPressEvent   window ( handleKeyboardPressEvent   )
+  _ <- GTK.onWidgetKeyReleaseEvent window ( handleKeyboardReleaseEvent )
+
+  _ <- GTK.onWidgetDestroy          window ( quitAll actionTVar )
+  _ <- GTK.onButtonClicked  quitIconButton ( quitAll actionTVar )
+
+  GTK.widgetShowAll window
+  GTK.main
--- a/assets/theme.css
+++ b/assets/theme.css
@ -0,0 +1,88 @@
+* {
+  all: unset;
+}
+
+/* Window background colour */
+.bg {
+  color: #292828
+}
+
+/* Viewport background colour */
+.viewport_bg {
+  color: #ecdfd2
+}
+
+/* Basic text colour */
+.plain {
+  color: #d4be98
+}
+
+/* Basic text font */
+.text {
+  font-family: "Lato", "Roboto", "Helvetica", sans-serif
+}
+
+/* Monospace font */
+.monospace {
+  font-family: "Fira Code", "Inconsolata", "Courier", "Courier New", monospace
+}
+
+/* High-constrast text colour */
+.contrast {
+  color: #f7f4ef
+}
+
+/* Active (highlighting) colour */
+.highlight {
+  color: #eadfcc
+}
+
+/* Logo base colour */
+.logo_base {
+  color: #f7f4ef
+}
+
+/* Logo highlight colour */
+.logo_highlight {
+  color: #f5881bff
+}
+
+/* Viewport scrollbar colour */
+.viewport_scrollbar {
+  color: #28272793
+}
+
+/* Tab scrollbar colour */
+.tab_scrollbar {
+  color: #302d2693
+}
+
+/* Ruler colour */
+.ruler {
+  color: #ede29a
+}
+
+/* Magnifying glass base colour */
+.magnifier {
+  color: #ecdfd2
+}
+
+/* Magnifying glass glass colour */
+.glass {
+  color: #9ce7ff72
+}
+
+/* Cursor colour */
+.cursor {
+  color: #f7f4ef
+}
+
+/* Bézier path point colour */
+.point {
+  color: #8183f1
+}
+
+/* Bézier control point colour */
+.control {
+  color: #a1dde9
+}
--- a/cabal.project
+++ b/cabal.project
@ -0,0 +1,10 @@
+constraints:
+    acts -finitary
+  , haskell-gi >= 0.24
+
+-- fixes gi-cairo-render to work with haskell-gi >= 0.24
+source-repository-package
+  type: git
+  location: https://github.com/thestr4ng3r/gi-cairo-render 
+  tag: 8727c43cdf91aeedffc9cb4c5575f56660a86399
+  subdir: gi-cairo-render
--- a/img/MetaBrush_ui_mockup.svg
+++ b/img/MetaBrush_ui_mockup.svg
--- a/img/logo.png
+++ b/img/logo.png
--- a/src/app/MetaBrush/Asset/Brush.hs
+++ b/src/app/MetaBrush/Asset/Brush.hs
@ -0,0 +1,60 @@
+module MetaBrush.Asset.Brush
+  ( drawBrush )
+  where
+
+-- gi-cairo-render
+import qualified GI.Cairo.Render as Cairo
+
+-- gi-gdk
+import qualified GI.Gdk as GDK
+
+-- MetaBrush
+import MetaBrush.Render.Util
+  ( withRGBA )
+
+--------------------------------------------------------------------------------
+
+-- | Calligraphy brush icon. Width = 29, height = 29.
+drawBrush :: GDK.RGBA -> GDK.RGBA -> GDK.RGBA -> Cairo.Render ()
+drawBrush brushColour bodyColour loopColour = do
+
+  -- Loop
+  Cairo.setLineWidth 0.2
+  withRGBA loopColour Cairo.setSourceRGBA
+  Cairo.newPath
+  Cairo.moveTo  23.144531 6.199219
+  Cairo.curveTo 22.40625  6.890625 21.382813 5.953125 20.375    7.300781
+  Cairo.curveTo 21.109375 5.925781 19.828125 5.410156 20.398438 4.324219
+  Cairo.curveTo 20.894531 3.375    21.757813 2.621094 23.046875 3.636719
+  Cairo.curveTo 24.035156 4.414063 24.128906 5.273438 23.144531 6.199219
+  Cairo.closePath
+  Cairo.strokePreserve
+
+  -- Brush body
+  withRGBA bodyColour Cairo.setSourceRGBA
+  Cairo.newPath
+  Cairo.moveTo  20.605469  7.359375
+  Cairo.curveTo 20.988281  7.566406 21.476563  8.136719 21.195313  8.464844
+  Cairo.lineTo  15.539063 14.84375
+  Cairo.lineTo  14.90625  18.964844
+  Cairo.curveTo 14.074219 19.195313 11.992188 17.941406 11.246094 17.457031
+  Cairo.curveTo 10.5      16.976563  9.460938 15.597656  9.816406 15.351563
+  Cairo.lineTo  13.507813 13.835938
+  Cairo.lineTo  18.980469  6.996094
+  Cairo.curveTo 19.25      6.660156 19.671875  6.613281 20         6.894531
+  Cairo.closePath
+  Cairo.fillPreserve
+
+  -- Brush tip
+  withRGBA brushColour Cairo.setSourceRGBA
+  Cairo.newPath
+  Cairo.moveTo  10.339844 19.335938
+  Cairo.curveTo 11.089844 19.847656 11.996094 20.34375  12.683594 20.507813
+  Cairo.curveTo 12.683594 20.507813  7.59375  24.476563  7.59375  24.476563
+  Cairo.curveTo  6.867188 25.160156  4.785156 26.105469  4.601563 25.941406
+  Cairo.curveTo  4.4375   25.792969  5.042969 24.261719  5.652344 23.140625
+  Cairo.curveTo  5.652344 23.140625  8.566406 17.773438  8.566406 17.773438
+  Cairo.curveTo  8.804688 18.136719  9.585938 18.820313 10.339844 19.335938
+  Cairo.curveTo 10.339844 19.335938 10.339844 19.335938 10.339844 19.335938
+  Cairo.closePath
+  Cairo.fillPreserve
--- a/src/app/MetaBrush/Asset/Logo.hs
+++ b/src/app/MetaBrush/Asset/Logo.hs
@ -0,0 +1,81 @@
+module MetaBrush.Asset.Logo
+  ( drawLogo )
+  where
+
+-- gi-cairo-render
+import qualified GI.Cairo.Render as Cairo
+
+-- gi-gdk
+import qualified GI.Gdk as GDK
+
+-- MetaBrush
+import MetaBrush.Render.Util
+  ( withRGBA )
+
+--------------------------------------------------------------------------------
+
+-- | MetaBrush logo. Width = 29, height = 29.
+drawLogo :: GDK.RGBA -> GDK.RGBA -> GDK.RGBA -> Cairo.Render ()
+drawLogo brushColour bodyColour loopColour = do
+
+  -- Loop
+  Cairo.setLineWidth 0.2
+  withRGBA loopColour Cairo.setSourceRGBA
+  Cairo.newPath
+  Cairo.moveTo  17.480469 7.847656
+  Cairo.curveTo 16.890625 8.402344 16.070313 7.648438 15.257813 8.730469
+  Cairo.curveTo 15.847656 7.625    14.820313 7.210938 15.277344 6.339844
+  Cairo.curveTo 15.675781 5.578125 16.371094 4.972656 17.40625  5.789063
+  Cairo.curveTo 18.199219 6.414063 18.273438 7.101563 17.480469 7.847656
+  Cairo.curveTo 17.480469 7.847656 17.480469 7.847656 17.480469 7.847656
+  Cairo.closePath
+  Cairo.strokePreserve
+
+  -- Body
+  withRGBA bodyColour Cairo.setSourceRGBA
+  Cairo.newPath
+  Cairo.moveTo  14.53125  8.257813
+  Cairo.curveTo 14.386719 8.273438  14.246094  8.351563 14.140625  8.484375
+  Cairo.curveTo 14.140625 8.484375   9.746094 13.976563  9.746094 13.976563
+  Cairo.curveTo  9.746094 13.976563  6.78125  15.195313  6.78125  15.195313
+  Cairo.curveTo  6.496094 15.390625  7.332031 16.5       7.929688 16.886719
+  Cairo.curveTo  8.53125  17.273438 10.199219 18.28125  10.867188 18.097656
+  Cairo.curveTo 10.867188 18.097656 11.375    14.789063 11.375    14.789063
+  Cairo.curveTo 11.375    14.789063 13.117188 12.824219 13.117188 12.824219
+  Cairo.curveTo 13.117188 12.824219 14.0625   11.660156 14.0625   11.660156
+  Cairo.curveTo 14.53125  12.59375  16.511719 16.417969 16.605469 16.535156
+  Cairo.curveTo 17.550781 16.058594 17.769531 15.773438 18.277344 15.167969
+  Cairo.curveTo 18.863281 14.359375 18.9375   14.257813 19.722656 13.226563
+  Cairo.curveTo 20.089844 13.980469 21.21875  15.222656 22.25     16.554688
+  Cairo.curveTo 22.636719 17.058594 24.300781 18.761719 24.785156 18.570313
+  Cairo.curveTo 25.046875 18.46875  25.972656 17.636719 26.136719 16.753906
+  Cairo.curveTo 26.171875 16.554688 26.265625 15.800781 26.097656 15.648438
+  Cairo.curveTo 25.976563 15.542969 24.988281 16.101563 24.679688 15.976563
+  Cairo.curveTo 24.144531 15.195313 23.488281 13.832031 22.921875 12.886719
+  Cairo.curveTo 22.023438 11.261719 21.320313  9.261719 20.597656  9.703125
+  Cairo.curveTo 20.09375  10.011719 19.808594 10.394531 19.699219 10.554688
+  Cairo.curveTo 19.195313 11.285156 18.960938 11.648438 18        12.988281
+  Cairo.curveTo 17.140625 11.703125 16.738281 10.175781 15.789063  9.058594
+  Cairo.curveTo 15.761719  9.03125  15.738281  9.011719 15.714844  8.992188
+  Cairo.curveTo 15.6875    8.960938 15.660156  8.9375   15.632813  8.914063
+  Cairo.curveTo 15.578125  8.871094 15.527344  8.832031 15.476563  8.800781
+  Cairo.curveTo 15.464844  8.792969 15.457031  8.78125  15.445313  8.777344
+  Cairo.curveTo 15.445313  8.777344 14.960938  8.40625  14.960938  8.40625
+  Cairo.curveTo 14.828125  8.292969 14.675781  8.246094 14.53125   8.257813
+  Cairo.curveTo 14.53125   8.257813 14.53125   8.257813 14.53125   8.257813
+  Cairo.closePath
+  Cairo.fillPreserve
+
+  -- Brush tip
+  withRGBA brushColour Cairo.setSourceRGBA
+  Cairo.newPath
+  Cairo.moveTo  7.199219 18.394531
+  Cairo.curveTo 7.804688 18.804688 8.53125  19.203125 9.082031 19.335938
+  Cairo.curveTo 9.082031 19.335938 4.996094 22.519531 4.996094 22.519531
+  Cairo.curveTo 4.414063 23.074219 2.742188 23.832031 2.59375  23.699219
+  Cairo.curveTo 2.460938 23.582031 2.949219 22.351563 3.4375   21.449219
+  Cairo.curveTo 3.4375   21.449219 5.777344 17.140625 5.777344 17.140625
+  Cairo.curveTo 5.96875  17.429688 6.597656 17.980469 7.199219 18.394531
+  Cairo.curveTo 7.199219 18.394531 7.199219 18.394531 7.199219 18.394531
+  Cairo.closePath
+  Cairo.fillPreserve
--- a/src/app/MetaBrush/Asset/Magnifier.hs
+++ b/src/app/MetaBrush/Asset/Magnifier.hs
@ -0,0 +1,60 @@
+module MetaBrush.Asset.Magnifier
+  ( drawMagnifier )
+  where
+
+-- gi-cairo-render
+import qualified GI.Cairo.Render as Cairo
+
+-- gi-gdk
+import qualified GI.Gdk as GDK
+
+-- MetaBrush
+import MetaBrush.Render.Util
+  ( withRGBA )
+
+--------------------------------------------------------------------------------
+
+-- | Magnifying glass icon. Width = 19, height = 25.
+drawMagnifier :: GDK.RGBA -> GDK.RGBA -> Cairo.Render ()
+drawMagnifier magnifierColour glassColour = do
+
+  -- Magnifying glass.
+  withRGBA glassColour Cairo.setSourceRGBA
+  Cairo.newPath
+  Cairo.moveTo  18.191406  6.144531
+  Cairo.curveTo 19.238281 10.191406 16.804688 14.324219 12.753906 15.371094
+  Cairo.curveTo  8.703125 16.417969  4.574219 13.984375  3.527344  9.933594
+  Cairo.curveTo  2.480469  5.882813  4.914063  1.753906  8.964844  0.707031
+  Cairo.curveTo 13.011719 -0.339844 17.144531  2.09375  18.191406  6.144531
+  Cairo.closePath
+  Cairo.fillPreserve
+
+  -- Magnifier.
+  withRGBA magnifierColour Cairo.setSourceRGBA
+  Cairo.newPath
+  Cairo.moveTo   11.144531  0.00390625
+  Cairo.curveTo  8.296875  -0.09375   5.484375   1.332031  3.933594  3.960938
+  Cairo.curveTo  1.871094   7.464844  2.980469  12.0625    6.089844 14.515625
+  Cairo.curveTo  5.878906  14.90625   5.226563  16.132813  4.554688 15.75
+  Cairo.curveTo  4.300781  15.609375  3.878906  15.882813  3.605469 16.363281
+  Cairo.lineTo   0.128906  22.34375
+  Cairo.curveTo -0.140625  22.828125  0.0273438 23.4375    0.503906 23.707031
+  Cairo.lineTo   2.320313  24.738281
+  Cairo.curveTo  2.800781  25.011719  3.410156  24.839844  3.683594 24.363281
+  Cairo.lineTo   7.148438  18.210938
+  Cairo.curveTo  7.421875  17.730469  7.34375   17.394531  7.09375  17.246094
+  Cairo.curveTo  6.445313  16.855469  7.1875    15.789063  7.449219 15.332031
+  Cairo.curveTo  11.136719 16.988281 15.683594  15.683594  17.78125 12.117188
+  Cairo.curveTo  20.035156  8.292969 18.761719   3.367188  14.9375   1.113281
+  Cairo.curveTo  13.742188  0.410156 12.441406   0.0507813 11.144531 0.00390625
+  Cairo.closePath
+  Cairo.moveTo   10.855469  1.375
+  Cairo.curveTo  13.894531  1.371094 16.550781  3.429688 17.3125    6.371094
+  Cairo.curveTo  18.234375  9.9375   16.089844 13.570313 12.527344 14.492188
+  Cairo.curveTo  8.960938  15.414063  5.328125 13.269531  4.40625   9.707031
+  Cairo.curveTo  3.484375   6.144531  5.625     2.507813  9.191406  1.585938
+  Cairo.curveTo  9.734375   1.445313 10.292969  1.375    10.855469  1.375
+  Cairo.closePath
+  Cairo.setFillRule Cairo.FillRuleWinding
+  Cairo.fillPreserve
+
--- a/src/app/MetaBrush/Asset/Meta.hs
+++ b/src/app/MetaBrush/Asset/Meta.hs
@ -0,0 +1,42 @@
+module MetaBrush.Asset.Meta
+  ( drawMeta )
+  where
+
+-- gi-cairo-render
+import qualified GI.Cairo.Render as Cairo
+
+-- gi-gdk
+import qualified GI.Gdk as GDK
+
+-- MetaBrush
+import MetaBrush.Render.Util
+  ( withRGBA )
+
+--------------------------------------------------------------------------------
+
+-- | MetaParameter icon. Width = 29, height = 29.
+drawMeta :: GDK.RGBA -> Cairo.Render ()
+drawMeta metaColour = do
+  withRGBA metaColour Cairo.setSourceRGBA
+  Cairo.newPath
+  Cairo.moveTo  16.140625 11.976563
+  Cairo.curveTo 15.042969 10.355469 13.957031  7.050781 13.257813  7.195313
+  Cairo.curveTo 12.878906  7.078125  5.332031 18.234375  4.664063 19.019531
+  Cairo.curveTo  3.90625  18.234375  2.886719 19.078125  2.800781 20.273438
+  Cairo.curveTo  2.800781 20.886719  4.28125  22.585938  5.566406 20.738281
+  Cairo.curveTo  5.6875   20.566406 11.421875 12.542969 11.957031 11.753906
+  Cairo.curveTo 12.421875 12.714844 14.351563 16.082031 14.46875  16.230469
+  Cairo.curveTo 15.605469 15.660156 15.863281 15.316406 16.476563 14.589844
+  Cairo.curveTo 17.171875 13.621094 17.265625 13.5      18.207031 12.261719
+  Cairo.curveTo 18.644531 13.164063 20        14.65625  21.238281 16.253906
+  Cairo.curveTo 21.703125 16.855469 23.695313 18.898438 24.28125  18.671875
+  Cairo.curveTo 24.589844 18.550781 25.699219 17.550781 25.894531 16.492188
+  Cairo.curveTo 25.941406 16.253906 26.050781 15.351563 25.847656 15.167969
+  Cairo.curveTo 25.707031 15.039063 24.519531 15.707031 24.148438 15.5625
+  Cairo.curveTo 23.507813 14.621094 22.722656 12.988281 22.042969 11.859375
+  Cairo.curveTo 20.964844  9.90625  20.125     7.507813 19.257813 8.039063
+  Cairo.curveTo 18.652344  8.410156 18.308594  8.867188 18.179688 9.058594
+  Cairo.curveTo 17.574219  9.9375   17.289063 10.367188 16.140625 11.976563
+  Cairo.curveTo 16.140625 11.976563 16.140625 11.976563 16.140625 11.976563
+  Cairo.closePath
+  Cairo.fillPreserve
--- a/src/app/MetaBrush/Asset/TickBox.hs
+++ b/src/app/MetaBrush/Asset/TickBox.hs
@ -0,0 +1,96 @@
+module MetaBrush.Asset.TickBox
+  ( drawBox, drawTickedBox )
+  where
+
+-- gi-cairo-render
+import qualified GI.Cairo.Render as Cairo
+
+-- gi-gdk
+import qualified GI.Gdk as GDK
+
+-- MetaBrush
+import MetaBrush.Render.Util
+  ( withRGBA )
+
+--------------------------------------------------------------------------------
+
+-- | Non-ticked box. Width = 14, height = 12.
+drawBox :: GDK.RGBA -> Cairo.Render ()
+drawBox boxColour = do
+  withRGBA loopColour Cairo.setSourceRGBA
+
+  Cairo.newPath
+  Cairo.moveTo   2.015625  0.769531
+  Cairo.curveTo  0.910156  0.769531  0         1.6875    0         2.789063
+  Cairo.lineTo   0        10
+  Cairo.curveTo  0        11.101563  0.910156 12.015625  2.015625 12.015625
+  Cairo.lineTo   9.226563 12.015625
+  Cairo.curveTo 10.328125 12.015625 11.246094 11.101563 11.246094 10
+  Cairo.lineTo  11.246094  2.789063
+  Cairo.curveTo 11.246094  1.6875   10.328125  0.769531  9.226563  0.769531
+  Cairo.closePath
+  Cairo.moveTo   2.015625  2.375
+  Cairo.lineTo   9.226563  2.375
+  Cairo.curveTo  9.46875   2.375    9.640625  2.546875 9.640625  2.789063
+  Cairo.lineTo   9.640625 10
+  Cairo.curveTo  9.640625 10.242188 9.46875  10.414063 9.226563 10.414063
+  Cairo.lineTo   2.015625 10.414063
+  Cairo.curveTo  1.769531 10.414063 1.597656 10.242188 1.597656 10
+  Cairo.lineTo   1.597656  2.789063
+  Cairo.curveTo  1.597656  2.546875 1.769531  2.375    2.015625  2.375
+  Cairo.closePath
+
+  Cairo.setFillRule Cairo.FillRuleWinding
+  Cairo.fillPreserve
+
+-- | Ticked box. Width = 14, height = 12.
+drawTickedBox :: GDK.RGBA -> GDK.RGBA -> Cairo.Render ()
+drawTickedBox boxColour tickColour = do
+
+  -- Box
+  withRGBA boxColour Cairo.setSourceRGBA
+  Cairo.newPath
+  Cairo.moveTo   2.015625  0.769531
+  Cairo.curveTo  0.910156  0.769531  0         1.679688  0         2.785156
+  Cairo.lineTo   0         9.996094
+  Cairo.curveTo  0        11.097656  0.910156 12.015625  2.015625 12.015625
+  Cairo.lineTo   9.226563 12.015625
+  Cairo.curveTo 10.328125 12.015625 11.246094 11.097656 11.246094  9.996094
+  Cairo.lineTo  11.246094  5.867188
+  Cairo.lineTo   9.640625  7.476563
+  Cairo.lineTo   9.640625  9.996094
+  Cairo.curveTo  9.640625 10.238281  9.46875  10.410156  9.226563 10.410156
+  Cairo.lineTo   2.015625 10.410156
+  Cairo.curveTo  1.769531 10.410156  1.597656 10.238281  1.597656  9.996094
+  Cairo.lineTo   1.597656  2.785156
+  Cairo.curveTo  1.597656  2.539063  1.769531  2.371094  2.015625  2.371094
+  Cairo.lineTo   9.226563  2.371094
+  Cairo.curveTo  9.277344  2.371094  9.324219  2.378906  9.367188  2.394531
+  Cairo.lineTo  10.511719  1.25
+  Cairo.curveTo 10.160156  0.957031  9.710938  0.769531  9.226563  0.769531
+  Cairo.closePath
+  Cairo.fillPreserve
+
+  -- Tickmark
+  withRGBA tickColour Cairo.setSourceRGBA
+  Cairo.newPath
+  Cairo.moveTo  13.40625  0.0078125
+  Cairo.curveTo 13.191406 0.0390625 12.96875   0.144531  12.785156 0.328125
+  Cairo.lineTo   6.511719 6.605469
+  Cairo.lineTo   4.597656 4.691406
+  Cairo.curveTo  4.230469 4.328125   3.710938  4.257813   3.425781 4.542969
+  Cairo.lineTo   3.144531 4.820313
+  Cairo.curveTo  2.863281 5.105469   2.929688  5.628906   3.300781 5.992188
+  Cairo.lineTo   5.8125   8.5
+  Cairo.curveTo  5.925781 8.609375   6.046875  8.683594   6.175781 8.738281
+  Cairo.curveTo  6.261719 8.78125    6.332031  8.804688   6.417969 8.816406
+  Cairo.curveTo  6.425781 8.816406   6.429688  8.816406   6.445313 8.816406
+  Cairo.curveTo  6.53125  8.824219   6.605469  8.820313   6.6875   8.796875
+  Cairo.curveTo  6.71875  8.789063   6.746094  8.785156   6.773438 8.773438
+  Cairo.curveTo  6.929688 8.722656   7.085938  8.644531   7.21875  8.511719
+  Cairo.lineTo  14.097656 1.625
+  Cairo.curveTo 14.464844 1.261719  14.53125   0.738281  14.253906 0.453125
+  Cairo.lineTo  13.976563 0.179688
+  Cairo.curveTo 13.835938 0.0351563 13.632813 -0.0195313 13.421875 0.0078125
+  Cairo.closePath
+  Cairo.fillPreserve
--- a/src/app/MetaBrush/Asset/WindowIcons.hs
+++ b/src/app/MetaBrush/Asset/WindowIcons.hs
@ -0,0 +1,31 @@
+module MetaBrush.Asset.WindowIcons
+  ( drawMinimise, drawRestoreDown, drawMaximise, drawClose )
+  where
+
+-- gi-cairo-render
+import qualified GI.Cairo.Render as Cairo
+
+-- gi-gdk
+import qualified GI.Gdk as GDK
+
+-- MetaBrush
+--import MetaBrush.Render.Util
+--  ( withRGBA )
+
+--------------------------------------------------------------------------------
+
+-- | Minimise window icon.
+drawMinimise :: GDK.RGBA -> Cairo.Render ()
+drawMinimise iconColour = pure ()
+
+-- | Restore down window icon.
+drawRestoreDown :: GDK.RGBA -> Cairo.Render ()
+drawRestoreDown iconColour = pure ()
+
+-- | Maximise window icon.
+drawMaximise :: GDK.RGBA -> Cairo.Render ()
+drawMaximise iconColour = pure ()
+
+-- | Close window icon.
+drawClose :: GDK.RGBA -> Cairo.Render ()
+drawClose iconColour = pure ()
--- a/src/app/MetaBrush/Document.hs
+++ b/src/app/MetaBrush/Document.hs
@ -0,0 +1,12 @@
+module MetaBrush.Document where
+
+--------------------------------------------------------------------------------
+
+data Document
+  = Document
+    { displayName    :: !Text
+    , filePath       :: !(Maybe FilePath)
+    , unsavedChanges :: !Bool
+    , viewport       :: !AABB
+    , strokes        :: !(Set Stroke)
+    }
--- a/src/app/MetaBrush/Render/Util.hs
+++ b/src/app/MetaBrush/Render/Util.hs
@ -0,0 +1,43 @@
+module MetaBrush.Render.Util
+  ( withRGBA, showRGBA
+  , widgetAddClasses, widgetAddClass )
+  where
+
+-- base
+import GHC.Stack
+  ( HasCallStack )
+
+-- gi-gdk
+import qualified GI.Gdk as GDK
+
+-- text
+import Data.Text
+  ( Text )
+import qualified Data.Text as Text
+  ( pack )
+
+-- transformers
+import Control.Monad.IO.Class
+  ( MonadIO(liftIO) )
+
+--------------------------------------------------------------------------------
+
+withRGBA :: MonadIO m => GDK.RGBA -> ( Double -> Double -> Double -> Double -> m b ) -> m b
+withRGBA rgba f = do
+  r <- GDK.getRGBARed   rgba
+  g <- GDK.getRGBAGreen rgba
+  b <- GDK.getRGBABlue  rgba
+  a <- GDK.getRGBAAlpha rgba
+  f r g b a
+
+showRGBA :: MonadIO m => GDK.RGBA -> m String
+showRGBA rgba = withRGBA rgba \ r g b a ->
+  pure $ "rgba(" ++ show r ++ "," ++ show g ++ "," ++ show b ++ "," ++ show a ++ ")"
+
+widgetAddClasses :: ( HasCallStack, GTK.IsWidget widget, MonadIO m ) => widget -> [Text] -> m ()
+widgetAddClasses widget classNames = do
+  styleContext <- GTK.widgetGetStyleContext widget
+  for_ classNames ( GTK.styleContextAddClass styleContext )
+
+widgetAddClass :: ( HasCallStack, GTK.IsWidget widget, MonadIO m ) => widget -> Text -> m ()
+widgetAddClass widget className = GTK.widgetGetStyleContext widget >>= ( `GTK.styleContextAddClass` className )
--- a/src/app/MetaBrush/Stroke.hs
+++ b/src/app/MetaBrush/Stroke.hs
@ -0,0 +1,11 @@
+module MetaBrush.Stroke where
+
+--------------------------------------------------------------------------------
+
+data StrokePoint
+  = StrokePoint
+    { center :: Point2D Double
+    , 
+
+newtype Stroke =
+  Stroke { strokePoints :: Seq ( 
--- a/src/lib/Math/Bezier/Cubic.hs
+++ b/src/lib/Math/Bezier/Cubic.hs
@ -0,0 +1,68 @@
+{-# LANGUAGE AllowAmbiguousTypes #-}
+{-# LANGUAGE DeriveFunctor       #-}
+{-# LANGUAGE DeriveFoldable      #-}
+{-# LANGUAGE DeriveGeneric       #-}
+{-# LANGUAGE DeriveTraversable   #-}
+{-# LANGUAGE DerivingStrategies  #-}
+{-# LANGUAGE RecordWildCards     #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TypeApplications    #-}
+
+module Math.Bezier.Cubic
+  ( Bezier(..)
+  , bezier, bezier'
+  )
+  where
+
+-- base
+import GHC.Generics
+  ( Generic )
+
+-- acts
+import Data.Act
+  ( Act
+    ( (•) )
+  , Torsor
+    ( (-->) )
+  )
+
+-- MetaBrush
+import Math.Module
+  ( Module (..)
+  , lerp
+  )
+import qualified Math.Bezier.Quadratic as Quadratic
+  ( Bezier(Bezier), bezier )
+
+--------------------------------------------------------------------------------
+
+-- | Points defining a cubic Bézier curve.
+--
+-- @ p0 @ and @ p3 @ are endpoints, whereas @ p1 @ and @ p2 @ are control points.
+data Bezier p
+  = Bezier
+    { p0 :: !p
+    , p1 :: !p
+    , p2 :: !p
+    , p3 :: !p
+    }
+  deriving stock ( Show, Generic, Functor, Foldable, Traversable )
+
+instance Module r p => Module r ( Bezier p ) where
+  ( Bezier p0 p1 p2 p3 ) ^+^ ( Bezier q0 q1 q2 q3 ) = Bezier ( p0 ^+^ q0 ) ( p1 ^+^ q1 ) ( p2 ^+^ q2 ) ( p3 ^+^ q3 )
+  r *^ bz = fmap ( r *^ ) bz
+
+-- | Cubic Bézier curve.
+bezier :: forall v r p. ( Torsor v p, Module r v ) => Bezier p -> r -> p
+bezier ( Bezier { .. } ) t =
+  lerp @v t
+    ( Quadratic.bezier ( Quadratic.Bezier p0 p1 p2 ) t )
+    ( Quadratic.bezier ( Quadratic.Bezier p1 p2 p3 ) t )
+
+-- | Derivative of cubic Bézier curve.
+bezier' :: forall v r p. ( Torsor v p, Module r v ) => Bezier p -> r -> v
+bezier' ( Bezier { .. } ) t
+  = ( 3 *^ )
+  $ lerp @v t
+      ( lerp @v t ( p0 --> p1 ) ( p1 --> p2 ) )
+      ( lerp @v t ( p1 --> p2 ) ( p2 --> p3 ) )
--- a/src/lib/Math/Bezier/Quadratic.hs
+++ b/src/lib/Math/Bezier/Quadratic.hs
@ -0,0 +1,58 @@
+{-# LANGUAGE AllowAmbiguousTypes #-}
+{-# LANGUAGE DeriveFunctor       #-}
+{-# LANGUAGE DeriveFoldable      #-}
+{-# LANGUAGE DeriveGeneric       #-}
+{-# LANGUAGE DeriveTraversable   #-}
+{-# LANGUAGE DerivingStrategies  #-}
+{-# LANGUAGE RecordWildCards     #-}
+{-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE TypeApplications    #-}
+
+module Math.Bezier.Quadratic
+  ( Bezier(..)
+  , bezier, bezier'
+  )
+  where
+
+-- base
+import GHC.Generics
+  ( Generic )
+
+-- acts
+import Data.Act
+  ( Act
+    ( (•) )
+  , Torsor
+    ( (-->) )
+  )
+
+-- MetaBrush
+import Math.Module
+  ( Module (..)
+  , lerp
+  )
+
+--------------------------------------------------------------------------------
+
+-- | Points defining a quadratic Bézier curve.
+--
+-- @ p0 @ and @ p2 @ are endpoints, whereas @ p1 @ is a control point.
+data Bezier p
+  = Bezier
+    { p0 :: !p
+    , p1 :: !p
+    , p2 :: !p
+    }
+  deriving stock ( Show, Generic, Functor, Foldable, Traversable )
+
+instance Module r p => Module r ( Bezier p ) where
+  ( Bezier p0 p1 p2 ) ^+^ ( Bezier q0 q1 q2 ) = Bezier ( p0 ^+^ q0 ) ( p1 ^+^ q1 ) ( p2 ^+^ q2 )
+  r *^ bz = fmap ( r *^ ) bz
+
+-- | Quadratic Bézier curve.
+bezier :: forall v r p. ( Torsor v p, Module r v ) => Bezier p -> r -> p
+bezier ( Bezier { .. } ) t = lerp @v t ( lerp @v t p0 p1 ) ( lerp @v t p1 p2 )
+
+-- | Derivative of quadratic Bézier curve.
+bezier' :: forall v r p. ( Torsor v p, Module r v ) => Bezier p -> r -> v
+bezier' ( Bezier { .. } ) t = 2 *^ lerp @v t ( p0 --> p1 ) ( p1 --> p2 )
--- a/src/lib/Math/Bezier/Stroke.hs
+++ b/src/lib/Math/Bezier/Stroke.hs
@ -0,0 +1,3 @@
+module Math.Bezier.Stroke where
+
+--------------------------------------------------------------------------------
--- a/src/lib/Math/Bezier/Subdivision.hs
+++ b/src/lib/Math/Bezier/Subdivision.hs
@ -0,0 +1,3 @@
+module Math.Bezier.Subdivision where
+
+--------------------------------------------------------------------------------
--- a/src/lib/Math/Module.hs
+++ b/src/lib/Math/Module.hs
@ -0,0 +1,41 @@
+{-# LANGUAGE AllowAmbiguousTypes   #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE ScopedTypeVariables   #-}
+
+module Math.Module
+  ( Module(..)
+  , lerp
+  )
+  where
+
+-- acts
+import Data.Act
+  ( Torsor
+    ( (-->) )
+  )
+
+--------------------------------------------------------------------------------
+
+infixl 6 ^+^, ^-^
+infix  8 ^*, *^
+
+class Num r => Module r m where
+
+  {-# MINIMAL (^+^), ( (^*) | (*^) ) #-}
+
+  (^+^) :: m -> m -> m
+  (^-^) :: m -> m -> m
+  (*^) :: r -> m -> m
+  (^*) :: m -> r -> m
+
+  (*^) = flip (^*)
+  (^*) = flip (*^)
+  m ^-^ n = m ^+^ (-1) *^ n
+
+instance Num a => Module a a where
+  (^+^) = (+)
+  (*^) = (*)
+  (^*) = (*)
+
+lerp :: forall v r p. ( Module r v , Torsor v p ) => r -> p -> p -> p
+lerp t p0 p1 = ( t *^ ( p0 --> p1 ) ) • p0
--- a/src/lib/Math/Vector2D.hs
+++ b/src/lib/Math/Vector2D.hs
@ -0,0 +1,51 @@
+{-# LANGUAGE DeriveFunctor              #-}
+{-# LANGUAGE DeriveFoldable             #-}
+{-# LANGUAGE DeriveGeneric              #-}
+{-# LANGUAGE DeriveTraversable          #-}
+{-# LANGUAGE DerivingVia                #-}
+{-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE MultiParamTypeClasses      #-}
+
+module Math.Vector2D
+  ( Point2D(..), Vector2D(..) )
+  where
+
+-- base
+import GHC.Generics
+  ( Generic )
+
+-- acts
+import Data.Act
+  ( Act, Torsor )
+
+-- generic-data
+import Data.Generic
+  ( GenericProduct(..) )
+
+-- groups
+import Data.Group
+  ( Group ( invert ) )
+
+-- MetaBrush
+import Math.Module
+  ( Module (..) )
+
+--------------------------------------------------------------------------------
+
+data Point2D a = Point2D !a !a
+  deriving stock ( Show, Generic, Functor, Foldable, Traversable )
+  deriving ( Act ( Vector2D a ), Torsor ( Vector2D a ) )
+    via Vector2D a
+
+newtype Vector2D a = Vector2D { tip :: Point2D a }
+  deriving stock Show
+  deriving ( Semigroup, Monoid, Group )
+    via GenericProduct ( Point2D ( Sum a ) )
+  deriving newtype ( Functor, Foldable, Traversable )
+
+instance Num a => Module a ( Vector2D a ) where
+  (^+^) = (<>)
+  p ^-^ q = p <> invert q
+
+  c *^ p = fmap ( c * ) p
+  p ^* c = fmap ( * c ) p