Merge pull request #67 from clojerl/54-image-related

[#54] image related

.gitignore

@@ -16,4 +16,6 @@ _build
 .idea
 *.iml
 rebar3.crashdump
-*~
+*~
+.clj-kondo/
+.lsp/

src/doodler/core.clje

@@ -401,14 +401,60 @@
   `width` and `height` parameters.
 
   In clj the `format` parameter defines how the pixels are stored.
-  See the PImage reference for more information.
+  See the wxImage reference for more information.
   Possible formats: `:rgb`, `:argb`, `:alpha` (grayscale alpha channel)
 
   Prefer using `create-image` over initialising new `wxImage` (or `Image`)
   instances directly."
   [w h]
   (p/create-image *canvas* w h))
 
+(defn load-image
+  "Loads an image into a variable of type wxImage. Four types of
+  images ( .gif, .jpg, .tga, .png) images may be loaded. To load
+  correctly, images must be located in the data directory of the
+  current sketch. In most cases, load all images in setup to preload
+  them at the start of the program. Loading images inside draw will
+  reduce the speed of a program.
+
+  The filename parameter can also be a URL to a file found online.
+
+  If an image is not loaded successfully, the null value is returned
+  and an error message will be printed to the console. The error
+  message does not halt the program, however the null value may cause
+  a NullPointerException if your code does not check whether the value
+  returned from load-image is nil.
+
+  Depending on the type of error, a wxImage object may still be
+  returned, but the width and height of the image will be set to
+  -1. This happens if bad image data is returned or cannot be decoded
+  properly. Sometimes this happens with image URLs that produce a 403
+  error or that redirect to a password prompt, because load-image
+  will attempt to interpret the HTML as image data."
+  [filename]
+  (p/load-image *canvas* (str filename)))
+
+
+(defn image
+  "Displays images to the screen. Processing currently works with GIF,
+  JPEG, and Targa images. The color of an image may be modified with
+  the tint function and if a GIF has transparency, it will maintain
+  its transparency. The img parameter specifies the image to display
+  and the x and y parameters define the location of the image from its
+  upper-left corner. The image is displayed at its original size
+  unless the width and height parameters specify a different size. The
+  image-mode fn changes the way the parameters work. A call to
+  (image-mode :corners) will change the width and height parameters to
+  define the x and y values of the opposite corner of the image.
+
+  Starting with release 0124, when using the default (JAVA2D)
+  renderer, smooth will also improve image quality of resized
+  images."
+  ([img x y]
+   (p/image *canvas* img x y))
+  ([img x y w h]
+   (p/image *canvas* img x y w h)))
+
 ;; Stroke & fill
 
 (defn- save-current-stroke

src/doodler/examples/image.clje

@@ -0,0 +1,21 @@
+;; Source: https://github.com/quil/quil/blob/master/README.md
+(ns doodler.examples.image
+  (:require [doodler.core :as d]))
+
+(defn setup
+  []
+  (d/frame-rate 60))
+
+(defn draw []
+  (d/background 200)
+  (d/text (str (d/current-frame-rate)) 0 10)
+  (let [img (d/load-image "resources/pacman.png")]
+    (d/image img 10 10 50 50)))
+
+(d/defsketch sketch
+  :title "Load image"
+  :size [323 200]
+  :setup setup
+  :draw draw
+  :features [:resizable :keep-on-top]
+  :bgcolor [200])

src/doodler/protocols.clje

@@ -6,7 +6,9 @@
   (height [this]))
 
 (defprotocol IBitmap
-  (create-image [this w h]))
+  (create-image [this w h])
+  (load-image [this filename])
+  (image [this img x y] [this img x y w h]))
 
 (defprotocol IPrimitives
   (arc [this x y w h start end])

src/doodler/wx/panel.clje

@@ -12,16 +12,28 @@
                       matrix
                       current-shape]
   p/ICanvas
-  (canvas [this] panel)
-  (width [this] width)
-  (height [this] height)
+  (canvas [_this] panel)
+  (width [_this] width)
+  (height [_this] height)
 
   p/IBitmap
-  (create-image [this w h]
+  (create-image [_this w h]
     (wxBitmap/new w h))
+  (load-image [_this filename]
+    (let [img (wxImage/new)]
+      (if (wxImage/loadFile img filename)
+        img
+        (throw (str "Could not load " filename)))))
+  (image [_this img x y]
+    (let [bitmap (wxBitmap/new img)]
+      (wxDC/drawBitmap bitmap-dc bitmap #erl[x y])))
+  (image [_this img x y w h]
+    (let [img (wxImage/scale img w h)
+          bitmap (wxBitmap/new img)]
+      (wxDC/drawBitmap bitmap-dc bitmap #erl[x y])))
 
   p/IPrimitives
-  (arc [this x y w h start end]
+  (arc [_this x y w h start end]
     (let [path (wxGraphicsContext/createPath @gc)
           r (/ (math/sqrt (+ (* w w) (* h h))) 2)]
       (wxGraphicsPath/addArc path
@@ -144,7 +156,7 @@
     (p/show-unsupported-warning! "print-camera"))
   (print-matrix [this]
     (let [m (wxGraphicsContext/getTransform @gc)
-          [a b c d tx ty](wxGraphicsMatrix/get m)]
+          [a b c d tx ty] (wxGraphicsMatrix/get m)]
       (println "Matrix:" :a a :b b :c c :d d :tx tx :ty ty)))
   (print-projection [this]
     (p/show-unsupported-warning! "print-projection"))