June 2018 Update

Task/Bitmap-Write-a-PPM-file/Erlang/bitmap-write-a-ppm-file.erl

@@ -0,0 +1,45 @@
+-module(ppm).
+
+-export([ppm/1, write/2]).
+
+-define(WHITESPACE, <<10>>).
+-define(SPACE, <<32>>).
+
+% data structure introduced in task Bitmap (module ros_bitmap.erl)
+-record(bitmap, {
+    pixels = nil,
+    shape = {0, 0}
+  }).
+
+% create ppm image from bitmap record
+ppm(Bitmap) ->
+    {Width, Height} = Bitmap#bitmap.shape,
+    Pixels = ppm_pixels(Bitmap),
+    Maxval = 255,  % original ppm format maximum
+    list_to_binary([
+      header(), width_and_height(Width, Height), maxval(Maxval), Pixels]).
+
+% write bitmap as ppm file
+write(Bitmap, Filename) ->
+    Ppm = ppm(Bitmap),
+    {ok, File} = file:open(Filename, [binary, write]),
+    file:write(File, Ppm),
+    file:close(File).
+
+%%%%%%%%%%%% four parts of ppm file %%%%%%%%%%%%%%%%%%%%%%
+header() ->
+    [<<"P6">>, ?WHITESPACE].
+
+width_and_height(Width, Height) ->
+    [encode_decimal(Width), ?SPACE, encode_decimal(Height), ?WHITESPACE].
+
+maxval(Maxval) ->
+   [encode_decimal(Maxval), ?WHITESPACE].
+
+ppm_pixels(Bitmap) ->
+    % 24 bit color depth
+    array:to_list(Bitmap#bitmap.pixels).
+
+%%%%%%%%%%%% Internals %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+encode_decimal(Number) ->
+    integer_to_list(Number).

Task/Bitmap-Write-a-PPM-file/Julia/bitmap-write-a-ppm-file.julia

@@ -0,0 +1,11 @@
+using Images, FileIO
+
+h, w = 50, 70
+img = zeros(RGB{N0f8}, h, w)
+img[10:40, 5:35] = colorant"skyblue"
+for i in 26:50, j in (i-25):40
+    img[i, j] = colorant"sienna1"
+end
+
+save("data/bitmapWrite.ppm", img)
+save("data/bitmapWrite.png", img)

Task/Bitmap-Write-a-PPM-file/Kotlin/bitmap-write-a-ppm-file.kotlin

@@ -0,0 +1,52 @@
+// Version 1.2.40
+
+import java.awt.Color
+import java.awt.Graphics
+import java.awt.image.BufferedImage
+import java.io.FileOutputStream
+
+class BasicBitmapStorage(width: Int, height: Int) {
+    val image = BufferedImage(width, height, BufferedImage.TYPE_3BYTE_BGR)
+
+    fun fill(c: Color) {
+        val g = image.graphics
+        g.color = c
+        g.fillRect(0, 0, image.width, image.height)
+    }
+
+    fun setPixel(x: Int, y: Int, c: Color) = image.setRGB(x, y, c.getRGB())
+
+    fun getPixel(x: Int, y: Int) = Color(image.getRGB(x, y))
+}
+
+fun main(args: Array<String>) {
+    // create BasicBitmapStorage object
+    val width = 640
+    val height = 640
+    val bbs = BasicBitmapStorage(width, height)
+    for (y in 0 until height) {
+        for (x in 0 until width) {
+            val c = Color(x % 256, y % 256, (x * y) % 256)
+            bbs.setPixel(x, y, c)
+        }
+    }
+
+    // now write it to a PPM file
+    val fos = FileOutputStream("output.ppm")
+    val buffer = ByteArray(width * 3)  // write one line at a time
+    fos.use {
+        val header = "P6\n$width $height\n255\n".toByteArray()
+        with (it) {
+            write(header)
+            for (y in 0 until height) {
+                for (x in 0 until width) {
+                    val c = bbs.getPixel(x, y)
+                    buffer[x * 3] = c.red.toByte()
+                    buffer[x * 3 + 1] = c.green.toByte()
+                    buffer[x * 3 + 2] = c.blue.toByte()
+                }
+                write(buffer)
+            }
+        }
+    }
+}

Task/Bitmap-Write-a-PPM-file/REXX/bitmap-write-a-ppm-file.rexx

@@ -1,17 +1,21 @@
-/*REXX program to write a  PPM  formatted image file,  P6 (binary).     */
-oFID   = 'IMAGE.PPM'                   /*name of the output file.       */
-green  = '00 ff 00'x
-image. = green                         /*define all IMAGE RGB's to green*/
- width = 20                            /*define the  width of  IMAGE.   */
-height = 20                            /*  "     "  height  "    "      */
-   sep = '9'x
-call put 'P6'width||sep||height||sep||255||sep      /*write header info.*/
-
-  do j      =1  for width
-        do k=1  for height
-        call put image.j.k             /*write IMAGE, 3 bytes at a time.*/
-        end   /*k*/
-  end         /*j*/
-exit                                   /*stick a fork in it, we're done.*/
-/*─────────────────────────────────────subroutines──────────────────────*/
-put:  call charout oFID,arg(1); return /*write out character(s) to file.*/
+/*REXX program writes a  PPM  formatted image file, also known as a  P6  (binary) file. */
+green  = 00ff00                                  /*define a pixel with the color green. */
+parse arg oFN width height color .               /*obtain optional arguments from the CL*/
+if    oFN=='' |    oFN==","  then    oFN='IMAGE' /*Not specified?  Then use the default.*/
+if  width=='' |  width==","  then  width=   20   /* "      "         "   "   "     "    */
+if height=='' | height==","  then height=   20   /* "      "         "   "   "     "    */
+if  color=='' |  color==","  then  color= green  /* "      "         "   "   "     "    */
+oFID= oFN'.PPM'                                  /*define  oFID  by adding an extension.*/
+ @. = x2c(color)                                 /*set all pixels of image a hex color. */
+ $  = '9'x                                       /*define the separator (in the header).*/
+ #  = 255                                        /*  "     "  max value for all colors. */
+call charout oFID, ,  1                          /*set the position of the file's output*/
+call charout oFID,'P6'width || $ || height || $ || # || $     /*write file header info. */
+_=
+       do j     =1  for width
+            do k=1  for height;  _=_ || @.j.k    /*write the PPM file, 1 pixel at a time*/
+            end   /*k*/                          /* ↑    a pixel contains three bytes,  */
+       end        /*j*/                          /* └────which defines the pixel's color*/
+call charout oFID, _                             /*write the image's raster to the file.*/
+call charout oFID                                /*close the output file just to be safe*/
+                                                 /*stick a fork in it,  we're all done. */