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http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#D
D
import bitmap: Image, RGB;   void circle(Color)(Image!Color img, in int x0, in int y0, in int radius, in Color color) pure nothrow @nogc @safe { int f = 1 - radius; int ddfX = 1; int ddfY = -2 * radius; int x = 0; int y = radius; img[x0, y0 + radius] = color; img[x0, y0 - ...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#11l
11l
T Colour Byte r, g, b   F ==(other) R .r == other.r & .g == other.g & .b == other.b   F (r, g, b) .r = r .g = g .b = b   V black = Colour(0, 0, 0) V white = Colour(255, 255, 255)   T Bitmap Int width, height Colour background [[Colour]] map   F (width = 40, height = 40, back...
http://rosettacode.org/wiki/Bitwise_IO
Bitwise IO
The aim of this task is to write functions (or create a class if your language is Object Oriented and you prefer) for reading and writing sequences of bits, most significant bit first. While the output of a asciiprint "STRING" is the ASCII byte sequence "S", "T", "R", "I", "N", "G", the output of a "print" of the bits ...
#Wren
Wren
import "io" for File   class BitFilter { construct new(name) { _name = name _accu = 0 _bits = 0 }   openWriter() { _bw = File.create(_name) }   openReader() { _br = File.open(_name) _offset = 0 }   write(buf, start, nBits, shift) { var ...
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#REXX
REXX
/*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...
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Ruby
Ruby
class RGBColour def values [@red, @green, @blue] end end   class Pixmap def save(filename) File.open(filename, 'w') do |f| f.puts "P6", "#{@width} #{@height}", "255" f.binmode @height.times do |y| @width.times do |x| f.print @data[x][y].values.pack('C3') end ...
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the vall...
#Ada
Ada
procedure Flood_Fill ( Picture  : in out Image; From  : Point; Fill  : Pixel; Replace  : Pixel; Distance : Luminance := 20 ) is function Diff (A, B : Luminance) return Luminance is pragma Inline (Diff); begin if A > B then...
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Crystal
Crystal
if false puts "false" elsif nil puts "nil" elsif Pointer(Nil).new 0 puts "null pointer" elsif true && "any other value" puts "finally true!" end
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#D
D
#t // <boolean> true #f // <boolean> false
http://rosettacode.org/wiki/Caesar_cipher
Caesar cipher
Task Implement a Caesar cipher, both encoding and decoding. The key is an integer from 1 to 25. This cipher rotates (either towards left or right) the letters of the alphabet (A to Z). The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A). So key 2 encrypts "HI" to...
#TUSCRIPT
TUSCRIPT
$$ MODE TUSCRIPT text="THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG" PRINT "text orginal ",text   abc="ABCDEFGHIJKLMNOPQRSTUVWXYZ",key=3,caesarskey=key+1 secretbeg=EXTRACT (abc,#caesarskey,0) secretend=EXTRACT (abc,0,#caesarskey) secretabc=CONCAT (secretbeg,secretend)   abc=STRINGS (abc,":</:"),secretabc=STRINGS (sec...
http://rosettacode.org/wiki/Box_the_compass
Box the compass
There be many a land lubber that knows naught of the pirate ways and gives direction by degree! They know not how to box the compass! Task description Create a function that takes a heading in degrees and returns the correct 32-point compass heading. Use the function to print and display a table of Index, Compass...
#BASIC256
BASIC256
arraybase 1   dim names$ = {"North", "North by east", "North-northeast", "Northeast by north", "Northeast", "Northeast by east", "East-northeast", "East by north", "East", "East by south", "East-southeast", "Southeast by east", "Southeast", "Southeast by south", "South-southeast", "South by east", "South", "South by we...
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh...
#Mathematica.2FWolfram_Language
Mathematica/Wolfram Language
ImageLevels[img]
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh...
#Nim
Nim
import bitmap import grayscale_image   type Histogram = array[Luminance, Natural]   #---------------------------------------------------------------------------------------------------   func histogram*(img: GrayImage): Histogram = ## Build and return gray scale image histogram. for lum in img.pixels: inc resul...
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh...
#OCaml
OCaml
type histogram = int array   let get_histogram ~img:gray_channel = let width = Bigarray.Array2.dim1 gray_channel and height = Bigarray.Array2.dim2 gray_channel in let t = Array.make 256 0 in for x = 0 to pred width do for y = 0 to pred height do let v = gray_get_pixel_unsafe gray_channel x y in ...
http://rosettacode.org/wiki/Bitwise_operations
Bitwise operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#ActionScript
ActionScript
function bitwise(a:int, b:int):void { trace("And: ", a & b); trace("Or: ", a | b); trace("Xor: ", a ^ b); trace("Not: ", ~a); trace("Left Shift: ", a << b); trace("Right Shift(Arithmetic): ", a >> b); trace("Right Shift(Logical): ", a >>> b); }
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Julia
Julia
// Version 1.2.40   import java.awt.Color import java.awt.Graphics import java.awt.image.BufferedImage import kotlin.math.abs import java.io.File import javax.imageio.ImageIO   class Point(var x: Int, var y: Int)   class BasicBitmapStorage(width: Int, height: Int) { val image = BufferedImage(width, height, Buffered...
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#ERRE
ERRE
PROGRAM BCircle   !$INCLUDE="PC.LIB"   PROCEDURE BCircle(cx%,cy%,r%) local f%,x%,y%,ddx%,ddy% f%=1-r% y%=r% ddy%=-2*r% PSET(cx%,cy%+r%,1) PSET(cx%,cy%-r%,1) PSET(cx%+r%,cy%,1) PSET(cx%-r%,cy%,1) WHILE x%<y% DO IF f%>=0 THEN y%=y%-1 ddy%=ddy%+2 ...
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#FBSL
FBSL
#DEFINE WM_LBUTTONDOWN 513 #DEFINE WM_CLOSE 16   FBSLSETTEXT(ME, "Bresenham Circle") ' Set form caption FBSLSETFORMCOLOR(ME, RGB(0, 255, 255)) ' Cyan: persistent background color FBSL.GETDC(ME) ' Use volatile FBSL.GETDC below to avoid extra assignments   RESIZE(ME, 0, 0, 220, 220) CENTER(ME) SHOW(ME)   DIM Breadth AS I...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#Action.21
Action!
INCLUDE "H6:RGBLINE.ACT" ;from task Bresenham's line algorithm INCLUDE "H6:REALMATH.ACT"   RGB black,yellow,violet,blue   TYPE IntPoint=[INT x,y]   PROC CubicBezier(RgbImage POINTER img IntPoint POINTER p1,p2,p3,p4 RGB POINTER col) INT i,n=[20],prevX,prevY,nextX,nextY REAL one,two,three,ri,rn,rt,ra,rb,rc,rd,tmp1,...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#Ada
Ada
procedure Cubic_Bezier ( Picture  : in out Image; P1, P2, P3, P4 : Point; Color  : Pixel; N  : Positive := 20 ) is Points : array (0..N) of Point; begin for I in Points'Range loop declare T : constant Float := Fl...
http://rosettacode.org/wiki/Bitwise_IO
Bitwise IO
The aim of this task is to write functions (or create a class if your language is Object Oriented and you prefer) for reading and writing sequences of bits, most significant bit first. While the output of a asciiprint "STRING" is the ASCII byte sequence "S", "T", "R", "I", "N", "G", the output of a "print" of the bits ...
#Z80_Assembly
Z80 Assembly
StoreBinaryString: ;INPUT: ; HL = SOURCE ADDRESS ; DE = OUTPUT STRING RAM ; BC = HOW MANY BYTES OF SOURCE DATA TO CONVERT ld a,(hl) push bc ld b,a ;backup a for later ld c,%10000000 ;a "revolving bit mask" is used to compare ; each bit of A, in sequence. loop: ld a,b ;restore A and c ld a,'0...
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Rust
Rust
use std::path::Path; use std::io::Write; use std::fs::File;   pub struct RGB { r: u8, g: u8, b: u8, }   pub struct PPM { height: u32, width: u32, data: Vec<u8>, }   impl PPM { pub fn new(height: u32, width: u32) -> PPM { let size = 3 * height * width; let buffer = vec![0; siz...
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Scala
Scala
object Pixmap { def save(bm:RgbBitmap, filename:String)={ val out=new DataOutputStream(new FileOutputStream(filename))   out.writeBytes("P6\u000a%d %d\u000a%d\u000a".format(bm.width, bm.height, 255))   for(y <- 0 until bm.height; x <- 0 until bm.width; c=bm.getPixel(x, y)){ out.writeByte(c...
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed st...
#C
C
#include <stdio.h> #include <string.h> #include <ctype.h> #include <openssl/sha.h> #include <openssl/ripemd.h>   #define COIN_VER 0 const char *coin_err;   typedef unsigned char byte;   int is_hex(const char *s) { int i; for (i = 0; i < 64; i++) if (!isxdigit(s[i])) return 0; return 1; }   void str_to_byte(const c...
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the vall...
#AutoHotkey
AutoHotkey
SetBatchLines, -1 CoordMode, Mouse CoordMode, Pixel CapsLock:: KeyWait, CapsLock MouseGetPos, X, Y PixelGetColor, color, X, Y FloodFill(x, y, color, 0x000000, 1, "CapsLock") MsgBox Done! Return FloodFill(x, y, target, replacement, mode=1, key="") { If GetKeyState(key, "P") Return PixelGetColor, color, x, y ...
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Dc
Dc
#t // <boolean> true #f // <boolean> false
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Delphi
Delphi
#t // <boolean> true #f // <boolean> false
http://rosettacode.org/wiki/Caesar_cipher
Caesar cipher
Task Implement a Caesar cipher, both encoding and decoding. The key is an integer from 1 to 25. This cipher rotates (either towards left or right) the letters of the alphabet (A to Z). The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A). So key 2 encrypts "HI" to...
#TXR
TXR
@(next :args) @(cases) @{key /[0-9]+/} @text @(or) @ (throw error "specify <key-num> <text>") @(end) @(do (defvar k (int-str key 10))) @(bind enc-dec @(collect-each ((i (range 0 25))) (let* ((p (tostringp (+ #\a i))) (e (tostringp (+ #\a (mod (+ i k) 26)))) (P (upc...
http://rosettacode.org/wiki/Box_the_compass
Box the compass
There be many a land lubber that knows naught of the pirate ways and gives direction by degree! They know not how to box the compass! Task description Create a function that takes a heading in degrees and returns the correct 32-point compass heading. Use the function to print and display a table of Index, Compass...
#BBC_BASIC
BBC BASIC
DIM bearing(32) bearing() = 0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, \ \ 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, \ \ 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, \ \ 270.0, 286.87, 286.88, 303.75, 320.62, 320.63, 337.5, 354.37, 354.38   ...
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh...
#Octave
Octave
function h = imagehistogram(imago) if ( isgray(imago) ) for j = 0:255 h(j+1) = numel(imago( imago == j )); endfor else error("histogram on gray img only"); endif endfunction   % test im = jpgread("Lenna100.jpg"); img = rgb2gray(im); h = imagehistogram(img); % let's try to show the histogram bar(...
http://rosettacode.org/wiki/Bitwise_operations
Bitwise operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#Ada
Ada
with Ada.Text_IO, Interfaces; use Ada.Text_IO, Interfaces;   procedure Bitwise is subtype Byte is Unsigned_8; package Byte_IO is new Ada.Text_Io.Modular_IO (Byte);   A : constant Byte  := 2#00011110#; B : constant Byte  := 2#11110100#; X : constant Byte  := 128; N : constant Natural := 1; begin...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Kotlin
Kotlin
// Version 1.2.40   import java.awt.Color import java.awt.Graphics import java.awt.image.BufferedImage import kotlin.math.abs import java.io.File import javax.imageio.ImageIO   class Point(var x: Int, var y: Int)   class BasicBitmapStorage(width: Int, height: Int) { val image = BufferedImage(width, height, Buffered...
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Forth
Forth
: circle { x y r color bmp -- } 1 r - 0 r 2* negate 0 r { f ddx ddy dx dy } color x y r + bmp b! color x y r - bmp b! color x r + y bmp b! color x r - y bmp b! begin dx dy < while f 0< 0= if dy 1- to dy ddy 2 + dup to ddy f + to f then dx 1+ ...
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Fortran
Fortran
interface draw_circle module procedure draw_circle_sc, draw_circle_rgb end interface   private :: plot, draw_circle_toch
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#ALGOL_68
ALGOL 68
# -*- coding: utf-8 -*- #   cubic bezier OF class image := ( REF IMAGE picture, POINT p1, p2, p3, p4, PIXEL color, UNION(INT, VOID) in n )VOID: BEGIN INT n = (in n|(INT n):n|20); # default 20 # [0:n]POINT points; FOR i FROM LWB points TO UPB points DO...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#BBC_BASIC
BBC BASIC
Width% = 200 Height% = 200   REM Set window size: VDU 23,22,Width%;Height%;8,16,16,128   REM Draw cubic Bézier curve: PROCbeziercubic(160,150, 10,120, 30,0, 150,50, 20, 0,0,0) END   DEF PROCbeziercubic(x1,y1,x2,y2,x3,y3,x4,y4,n%,r%,g%,b%) LOCAL i%, t, t1, a, b, c, d...
http://rosettacode.org/wiki/Bitwise_IO
Bitwise IO
The aim of this task is to write functions (or create a class if your language is Object Oriented and you prefer) for reading and writing sequences of bits, most significant bit first. While the output of a asciiprint "STRING" is the ASCII byte sequence "S", "T", "R", "I", "N", "G", the output of a "print" of the bits ...
#zkl
zkl
// stream of numBits sized ints to bytes, numBits<8 fcn toBytes(n,[(numBits,acc,bitsSoFar)]state){ acc=acc.shiftLeft(numBits) + n; bitsSoFar+=numBits; reg r; if(bitsSoFar>=8){ bitsSoFar-=8; r=acc.shiftRight(bitsSoFar); acc=acc.bitAnd((-1).shiftLeft(bitsSoFar).bitNot()); } else r=Void...
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Scheme
Scheme
(define (write-ppm image file) (define (write-image image) (define (write-row row) (define (write-colour colour) (if (not (null? colour)) (begin (write-char (integer->char (car colour))) (write-colour (cdr colour))))) (if (not (null? row)) (begin (write...
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed st...
#Common_Lisp
Common Lisp
  ;;;; This is a revised version, inspired by a throwaway script originally ;;;; published at http://deedbot.org/bundle-381528.txt by the same Adlai.   ;;; package definition (cl:defpackage :bitcoin-address-encoder (:use :cl . #.(ql:quickload :ironclad)) (:shadowing-import-from :ironclad #:null) (:import-from :ir...
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the vall...
#BBC_BASIC
BBC BASIC
MODE 8 GCOL 15 CIRCLE FILL 640, 512, 500 GCOL 0 CIRCLE FILL 500, 600, 200 GCOL 3 PROCflood(600, 200, 15) GCOL 4 PROCflood(600, 700, 0) END   DEF PROCflood(X%, Y%, C%) LOCAL L%, R% IF POINT(X%,Y%) <> C% ENDPROC L% = X% R% = X% ...
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the vall...
#C
C
/* * RosettaCode: Bitmap/Flood fill, language C, dialects C89, C99, C11. * * This is an implementation of the recursive algorithm. For the sake of * simplicity, instead of reading files as JPEG, PNG, etc., the program * read and write Portable Bit Map (PBM) files in plain text format. * Portable Bit Map files c...
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#DWScript
DWScript
#t // <boolean> true #f // <boolean> false
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Dyalect
Dyalect
#t // <boolean> true #f // <boolean> false
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#Dylan
Dylan
#t // <boolean> true #f // <boolean> false
http://rosettacode.org/wiki/Caesar_cipher
Caesar cipher
Task Implement a Caesar cipher, both encoding and decoding. The key is an integer from 1 to 25. This cipher rotates (either towards left or right) the letters of the alphabet (A to Z). The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A). So key 2 encrypts "HI" to...
#TypeScript
TypeScript
function replace(input: string, key: number) : string { return input.replace(/([a-z])/g, ($1) => String.fromCharCode(($1.charCodeAt(0) + key + 26 - 97) % 26 + 97) ).replace(/([A-Z])/g, ($1) => String.fromCharCode(($1.charCodeAt(0) + key + 26 - 65) % 26 + 65)); }   // test var str = 'The five boxing wizards jum...
http://rosettacode.org/wiki/Box_the_compass
Box the compass
There be many a land lubber that knows naught of the pirate ways and gives direction by degree! They know not how to box the compass! Task description Create a function that takes a heading in degrees and returns the correct 32-point compass heading. Use the function to print and display a table of Index, Compass...
#Befunge
Befunge
>>::"}"9**\4+3%79*9*5-*79*9*5--+:5>>>06p:55+%68*+v ^_@#!`*84:+1<v*9"}"*+55,,,".",,,$$_^#!:-1g60/+55\< >_06g:v>55+,^>/5+55+/48*::::,,,,%:1+.9,:06p48*\-0v |p60-1<|<!p80:<N|Ev"northwest"0"North by west"0p8< >:#,_>>>_08g1-^W|S>"-htroN"0"htron yb tsewhtroN"0v #v"est-northwest"0"Northwest by west"0"Northwest"< N>"W"0"htron y...
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh...
#Phix
Phix
-- demo\rosetta\Bitmap_Histogram.exw (runnable version) include ppm.e -- black, white, read_ppm(), write_ppm() (covers above requirements)   function to_bw(sequence image) sequence hist = repeat(0,256) for x=1 to length(image) do for y=1 to length(image[x]) do integer pixel = image[x][y]...
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh...
#PHP
PHP
  define('src_name', 'input.jpg'); // source image define('dest_name', 'output.jpg'); // destination image   $img = imagecreatefromjpeg(src_name); // read image   if(empty($img)){ echo 'Image could not be loaded!'; exit; }   $black = imagecolorallocate($img, 0, 0, 0); $white = imagecolorallocate($img, 255, 255, 255...
http://rosettacode.org/wiki/Bitwise_operations
Bitwise operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#Aikido
Aikido
function bitwise(a, b){ println("a AND b: " + (a & b)) println("a OR b: "+ (a | b)) println("a XOR b: "+ (a ^ b)) println("NOT a: " + ~a) println("a << b: " + (a << b)) // left shift println("a >> b: " + (a >> b)) // arithmetic right shift println("a >>> b: " + (a >>> b)) // logical right shift }
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Lua
Lua
Bitmap.quadraticbezier = function(self, x1, y1, x2, y2, x3, y3, nseg) nseg = nseg or 10 local prevx, prevy, currx, curry for i = 0, nseg do local t = i / nseg local a, b, c = (1-t)^2, 2*t*(1-t), t^2 prevx, prevy = currx, curry currx = math.floor(a * x1 + b * x2 + c * x3 + 0.5) curry = math.flo...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Mathematica_.2F_Wolfram_Language
Mathematica / Wolfram Language
pts = {{0, 0}, {1, -1}, {2, 1}}; Graphics[{BSplineCurve[pts], Green, Line[pts], Red, Point[pts]}]
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#FreeBASIC
FreeBASIC
' version 15-10-2016 ' compile with: fbc -s gui   ' Variant with Integer-Based Arithmetic from Wikipedia page: ' Midpoint circle algorithm Sub circle_(x0 As Integer, y0 As Integer , radius As Integer, Col As Integer)   Dim As Integer x = radius Dim As Integer y ' Decision criterion divided by 2 evaluated at x=r, ...
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Go
Go
package raster   // Circle plots a circle with center x, y and radius r. // Limiting behavior: // r < 0 plots no pixels. // r = 0 plots a single pixel at x, y. // r = 1 plots four pixels in a diamond shape around the center pixel at x, y. func (b *Bitmap) Circle(x, y, r int, p Pixel) { if r < 0 { return ...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#C
C
void cubic_bezier( image img, unsigned int x1, unsigned int y1, unsigned int x2, unsigned int y2, unsigned int x3, unsigned int y3, unsigned int x4, unsigned int y4, color_component r, color_component g, color_component b );
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#D
D
import grayscale_image, bitmap_bresenhams_line_algorithm;   struct Pt { int x, y; } // Signed.   void cubicBezier(size_t nSegments=20, Color) (Image!Color im, in Pt p1, in Pt p2, in Pt p3, in Pt p4, in Color color) pure nothrow @nogc if (nSegments > 0) { Pt[nSegment...
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Seed7
Seed7
$ include "seed7_05.s7i"; include "draw.s7i"; include "color.s7i";   const proc: writePPM (in string: fileName, in PRIMITIVE_WINDOW: aWindow) is func local var file: ppmFile is STD_NULL; var integer: x is 0; var integer: y is 0; var color: pixColor is black; begin ppmFile := open(fileName, "...
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Sidef
Sidef
subset Int < Number {|n| n.is_int } subset UInt < Int {|n| n >= 0 } subset UInt8 < Int {|n| n ~~ ^256 }   struct Pixel { R < UInt8, G < UInt8, B < UInt8 }   class Bitmap(width < UInt, height < UInt) { has data = []   method fill(Pixel p) { data = (width*height -> of { Pixel(p.R,...
http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm
Bitmap/Bresenham's line algorithm
Task Using the data storage type defined on the Bitmap page for raster graphics images, draw a line given two points with Bresenham's line algorithm.
#11l
11l
T Colour Byte r, g, b   F (r, g, b) .r = r .g = g .b = b   F ==(other) R .r == other.r & .g == other.g & .b == other.b   V black = Colour(0, 0, 0) V white = Colour(255, 255, 255)   T Bitmap Int width, height Colour background [[Colour]] map   F (width = 40, height = 40, back...
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed st...
#D
D
import std.stdio, std.algorithm, std.digest.ripemd, sha_256_2;   // A Bitcoin public point. struct PPoint { ubyte[32] x, y; }   private enum bitcoinVersion = 0; private enum RIPEMD160_digest_len = typeof("".ripemd160Of).length; private alias sha = SHA256.digest; alias Address = ubyte[1 + 4 + RIPEMD160_digest_len];     ...
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the vall...
#C.23
C#
  using System; using System.Collections.Generic; using System.Drawing;   namespace FloodFill { class Program { private static bool ColorMatch(Color a, Color b) { return (a.ToArgb() & 0xffffff) == (b.ToArgb() & 0xffffff); }   static void FloodFill(Bitmap bmp, Point pt...
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#D.C3.A9j.C3.A0_Vu
Déjà Vu
? if (true) { "a" } else { "b" } # value: "a"   ? if (false) { "a" } else { "b" } # value: "b"   ? if (90) { "a" } else { "b" } # problem: the int 90 doesn't coerce to a boolean
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#E
E
? if (true) { "a" } else { "b" } # value: "a"   ? if (false) { "a" } else { "b" } # value: "b"   ? if (90) { "a" } else { "b" } # problem: the int 90 doesn't coerce to a boolean
http://rosettacode.org/wiki/Caesar_cipher
Caesar cipher
Task Implement a Caesar cipher, both encoding and decoding. The key is an integer from 1 to 25. This cipher rotates (either towards left or right) the letters of the alphabet (A to Z). The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A). So key 2 encrypts "HI" to...
#UNIX_Shell
UNIX Shell
caesar() { local OPTIND local encrypt n=0 while getopts :edn: option; do case $option in e) encrypt=true ;; d) encrypt=false ;; n) n=$OPTARG ;;  :) echo "error: missing argument for -$OPTARG" >&2 return 1 ;;  ?) echo "error: un...
http://rosettacode.org/wiki/Box_the_compass
Box the compass
There be many a land lubber that knows naught of the pirate ways and gives direction by degree! They know not how to box the compass! Task description Create a function that takes a heading in degrees and returns the correct 32-point compass heading. Use the function to print and display a table of Index, Compass...
#C
C
#include <stdio.h>   int main() { int i, j; double degrees[] = { 0.0, 16.87, 16.88, 33.75, 50.62, 50.63, 67.5, 84.37, 84.38, 101.25, 118.12, 118.13, 135.0, 151.87, 151.88, 168.75, 185.62, 185.63, 202.5, 219.37, 219.38, 236.25, 253.12, 253.13, 270.0, 286.87...
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh...
#PicoLisp
PicoLisp
(de histogram (Pgm) (let H (need 256 0) (for L Pgm (for G L (inc (nth H (inc G))) ) ) H ) )
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh...
#PureBasic
PureBasic
Procedure getHistogram(image, Array histogram(1)) Protected w = ImageWidth(image) - 1 Protected h = ImageHeight(image) - 1 Dim histogram(255) ;output   StartDrawing(ImageOutput(image)) For x = 0 To w For y = 0 To h lum = Red(Point(x, y)) ;the Green or Blue color components could be used also ...
http://rosettacode.org/wiki/Bitwise_operations
Bitwise operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#ALGOL_68
ALGOL 68
main:(   PRIO SLC = 8, SRC = 8; # SLC and SRC are not built in, define and overload them here # OP SLC = (BITS b, INT rotate) BITS: b SHL rotate OR b SHR ( bits width - rotate ); OP SRC = (BITS b, INT rotate) BITS: b SHR rotate OR b SHL ( bits width - rotate ); # SRC and SRL are non-standard, but versions are b...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#MATLAB
MATLAB
  function bezierQuad(obj,pixel_0,pixel_1,pixel_2,color,varargin)   if( isempty(varargin) ) resolution = 20; else resolution = varargin{1}; end   %Calculate time axis time = (0:1/resolution:1)'; timeMinus = 1-time;   %The formula for the curve is expanded for clarity, the lac...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Nim
Nim
import bitmap import bresenham import lenientops   proc drawQuadraticBezier*( image: Image; pt1, pt2, pt3: Point; color: Color; nseg: Positive = 20) =   var points = newSeq[Point](nseg + 1)   for i in 0..nseg: let t = i / nseg let a = (1 - t) * (1 - t) let b = 2 * t * (1 - t) let c = t * t  ...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#OCaml
OCaml
let quad_bezier ~img ~color ~p1:(_x1, _y1) ~p2:(_x2, _y2) ~p3:(_x3, _y3) = let (x1, y1, x2, y2, x3, y3) = (float _x1, float _y1, float _x2, float _y2, float _x3, float _y3) in let bz t = let a = (1.0 -. t) ** 2.0 and b = 2.0 *. t *. (1.0 -. t) and c = t ** 2.0 in le...
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Haskell
Haskell
module Circle where   import Data.List   type Point = (Int, Int)   -- Takes the center of the circle and radius, and returns the circle points generateCirclePoints :: Point -> Int -> [Point] generateCirclePoints (x0, y0) radius -- Four initial points, plus the generated points = (x0, y0 + radius) : (x0, y0 - radius...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#F.23
F#
  /// Uses Vector<float> from Microsoft.FSharp.Math (in F# PowerPack) module CubicBezier   /// Create bezier curve from p1 to p4, using the control points p2, p3 /// Returns the requested number of segments let cubic_bezier (p1:vector) (p2:vector) (p3:vector) (p4:vector) segments = [0 .. segments - 1] |> Li...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#Factor
Factor
USING: arrays kernel locals math math.functions rosettacode.raster.storage sequences ; IN: rosettacode.raster.line   ! this gives a function :: (cubic-bezier) ( P0 P1 P2 P3 -- bezier ) [ :> x 1 x - 3 ^ P0 n*v 1 x - sq 3 * x * P1 n*v 1 x - 3 * x sq * P2 n*v x 3 ^ P3 n*v v+ v+...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#FBSL
FBSL
#DEFINE WM_LBUTTONDOWN 513 #DEFINE WM_CLOSE 16   FBSLSETTEXT(ME, "Bezier Cubic") FBSLSETFORMCOLOR(ME, RGB(0, 255, 255)) ' Cyan: persistent background color DRAWWIDTH(5) ' Adjust point size FBSL.GETDC(ME) ' Use volatile FBSL.GETDC below to avoid extra assignments   RESIZE(ME, 0, 0, 235, 235) CENTER(ME) SHOW(ME)   DIM He...
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Stata
Stata
mata void writeppm(name, r, g, b) { n = rows(r) p = cols(r) f = fopen(name, "w") fput(f, "P3") fput(f, strofreal(p) + " " + strofreal(n) + " 255") for (i = 1; i <= n; i++) { for (j = 1; j <= p; j++) { fput(f, strofreal(r[i,j]) + " " + strofreal(g[i,j]) + " " + strofreal(b[i,j])) } } fclose(f) }   r = J(1...
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Tcl
Tcl
package require Tk   proc output_ppm {image filename} { $image write $filename -format ppm }   set img [newImage 150 150] fill $img red setPixel $img green 40 40 output_ppm $img filename.ppm   # check the file format: set fh [open filename.ppm] puts [gets $fh] ;# ==> P6 puts [gets $fh] ;# ==> 150 150 puts [gets $fh...
http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm
Bitmap/Bresenham's line algorithm
Task Using the data storage type defined on the Bitmap page for raster graphics images, draw a line given two points with Bresenham's line algorithm.
#360_Assembly
360 Assembly
* Bitmap/Bresenham's line algorithm - 13/05/2019 BRESENH CSECT USING BRESENH,R13 base register B 72(R15) skip savearea DC 17F'0' savearea SAVE (14,12) save previous context ST R13,4(R15) link backward ...
http://rosettacode.org/wiki/Bitcoin/address_validation
Bitcoin/address validation
Bitcoin/address validation You are encouraged to solve this task according to the task description, using any language you may know. Task Write a program that takes a bitcoin address as argument, and checks whether or not this address is valid. A bitcoin address uses a base58 encoding, which uses an alphabet of th...
#Ada
Ada
with Ada.Exceptions, Interfaces; with Ada.Streams; use Ada.Exceptions, Interfaces; use Ada.Streams;   package Bitcoin is subtype BT_Raw_Addr is Stream_Element_Array(1..25); subtype BT_Checksum is Stream_Element_Array(1..4); subtype BT_Addr is String(1..34); subtype Sha256String is String(1..64); Inv...
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed st...
#Delphi
Delphi
  program Public_point_to_address;   {$APPTYPE CONSOLE}   uses System.SysUtils, Winapi.Windows, DCPsha256, DCPripemd160;   const bitcoinVersion = 0;   type TByteArray = array of Byte;   TA25 = TByteArray;   TPPoint = record x, y: TByteArray; constructor SetHex(xi, yi: ansistring); end;   TA2...
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the vall...
#C.2B.2B
C++
#ifndef PROCESSING_FLOODFILLALGORITHM_H_ #define PROCESSING_FLOODFILLALGORITHM_H_   #include <opencv2/opencv.hpp> #include <string.h> #include <queue>   using namespace cv; using namespace std;   class FloodFillAlgorithm { public: FloodFillAlgorithm(Mat* image) : image(image) { } virtual ~FloodFillA...
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the vall...
#D
D
import std.array, bitmap;   void floodFill(Color)(Image!Color img, in uint x, in uint y, in Color color) /*pure*/ nothrow in { assert (y < img.ny && x < img.nx); } body { immutable target = img[x, y]; static struct Pos { uint x, y; } auto stack = [Pos(x, y)];   while (!stack.em...
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#EchoLisp
EchoLisp
  (not #t) → #f (not #f) → #t (not null) → #f (not 0) → #f  
http://rosettacode.org/wiki/Boolean_values
Boolean values
Task Show how to represent the boolean states "true" and "false" in a language. If other objects represent "true" or "false" in conditionals, note it. Related tasks   Logical operations
#EGL
EGL
  myBool boolean = 0; SysLib.writeStdout("myBool: " + StrLib.booleanAsString(myBool)); myBool = 1; SysLib.writeStdout("myBool: " + StrLib.booleanAsString(myBool)); myBool = 2; SysLib.writeStdout("myBool: " + StrLib.booleanAsString(myBool)); myBool = false; SysLib.writeStdout("myBool: " + StrLib.booleanAsString(myBool))...
http://rosettacode.org/wiki/Caesar_cipher
Caesar cipher
Task Implement a Caesar cipher, both encoding and decoding. The key is an integer from 1 to 25. This cipher rotates (either towards left or right) the letters of the alphabet (A to Z). The encoding replaces each letter with the 1st to 25th next letter in the alphabet (wrapping Z to A). So key 2 encrypts "HI" to...
#Ursa
Ursa
decl string mode while (not (or (= mode "encode") (= mode "decode"))) out "encode/decode: " console set mode (lower (in string console)) end while   decl string message out "message: " console set message (upper (in string console))   decl int key out "key: " console set key (in int console) if (or (>...
http://rosettacode.org/wiki/Box_the_compass
Box the compass
There be many a land lubber that knows naught of the pirate ways and gives direction by degree! They know not how to box the compass! Task description Create a function that takes a heading in degrees and returns the correct 32-point compass heading. Use the function to print and display a table of Index, Compass...
#C.23
C#
  using System; using System.Collections.Generic;   namespace BoxTheCompass { class Compass { string[] cp = new string[] {"North", "North by east", "North-northeast", "Northeast by north", "Northeast","Northeast by east", "East-northeast", "East by north", "East", "East by south", "East-southeast"...
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh...
#Python
Python
from PIL import Image   # Open the image image = Image.open("lena.jpg") # Get the width and height of the image width, height = image.size # Calculate the amount of pixels amount = width * height   # Total amount of greyscale total = 0 # B/W image bw_image = Image.new('L', (width, height), 0) # Bitmap image bm_image = ...
http://rosettacode.org/wiki/Bitmap/Histogram
Bitmap/Histogram
Extend the basic bitmap storage defined on this page to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, wh...
#Racket
Racket
#lang racket (require racket/draw math/statistics racket/require (filtered-in (lambda (name) (regexp-replace #rx"unsafe-" name "")) racket/unsafe/ops))   ;; CIE formula as discussed in "Greyscale image" task (define (L r g b)  ;; In fact there is no need, statistically for L to be divided...
http://rosettacode.org/wiki/Bitwise_operations
Bitwise operations
Basic Data Operation This is a basic data operation. It represents a fundamental action on a basic data type. You may see other such operations in the Basic Data Operations category, or: Integer Operations Arithmetic | Comparison Boolean Operations Bitwise | Logical String Operations Concatenation | Interpolation |...
#ALGOL_W
ALGOL W
% performs bitwise and, or, not, left-shift and right shift on the integers n1 and n2 % % Algol W does not have xor, arithmetic right shift, left rotate or right rotate  % procedure bitOperations ( integer value n1, n2 ) ; begin bits b1, b2;  % the Algol W bitwse operations operate on bits values, so we firs...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#Phix
Phix
-- demo\rosetta\Bitmap_BezierQuadratic.exw include ppm.e -- black, green, red, white, new_image(), write_ppm(), bresLine() -- (covers above requirements)   function quadratic_bezier(sequence img, atom x1, y1, x2, y2, x3, y3, integer colour, segments) sequence pts = repeat(0,segments*2) for i=0 to segments*2-1 ...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#PicoLisp
PicoLisp
(scl 6)   (de quadBezier (Img N X1 Y1 X2 Y2 X3 Y3) (let (R (* N N) X X1 Y Y1 DX 0 DY 0) (for I N (let (J (- N I) A (*/ 1.0 J J R) B (*/ 2.0 I J R) C (*/ 1.0 I I R)) (brez Img X Y (setq DX (- (+ (*/ A X1 1.0) (*/ B X2 1.0) (*/ C X3 1.0)) X)) (setq DY (- ...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Quadratic
Bitmap/Bézier curves/Quadratic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this one, draw a quadratic bezier curve (definition on Wikipedia).
#PureBasic
PureBasic
Procedure quad_bezier(img, p1x, p1y, p2x, p2y, p3x, p3y, Color, n_seg) Protected i Protected.f T, t1, a, b, c, d Dim pts.POINT(n_seg)   For i = 0 To n_seg T = i / n_seg t1 = 1.0 - T a = Pow(t1, 2) b = 2.0 * T * t1 c = Pow(T, 2) pts(i)\x = a * p1x + b * p2x + c * p3x pts(i)\y = a * p1...
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#J
J
NB.*getBresenhamCircle v Returns points for a circle given center and radius NB. y is: y0 x0 radius getBresenhamCircle=: monad define 'y0 x0 radius'=. y x=. 0 y=. radius f=. -. radius pts=. 0 2$0 while. x <: y do. pts=. pts , y , x if. f >: 0 do. y=. <:y f=. f + _2 * y end. x=. >...
http://rosettacode.org/wiki/Bitmap/Midpoint_circle_algorithm
Bitmap/Midpoint circle algorithm
Task Using the data storage type defined on this page for raster images, write an implementation of the midpoint circle algorithm   (also known as Bresenham's circle algorithm). (definition on Wikipedia).
#Java
Java
  import java.awt.Color;   public class MidPointCircle { private BasicBitmapStorage image;   public MidPointCircle(final int imageWidth, final int imageHeight) { this.image = new BasicBitmapStorage(imageWidth, imageHeight); }   private void drawCircle(final int centerX, final int centerY, final int radius) { in...
http://rosettacode.org/wiki/Bitmap/B%C3%A9zier_curves/Cubic
Bitmap/Bézier curves/Cubic
Using the data storage type defined on this page for raster images, and the draw_line function defined in this other one, draw a cubic bezier curve (definition on Wikipedia).
#Fortran
Fortran
subroutine cubic_bezier(img, p1, p2, p3, p4, color) type(rgbimage), intent(inout) :: img type(point), intent(in) :: p1, p2, p3, p4 type(rgb), intent(in) :: color   integer :: i, j real :: pts(0:N_SEG,0:1), t, a, b, c, d, x, y   do i = 0, N_SEG t = real(i) / real(N_SEG) a = (1.0 - t)**3.0 b = ...
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#UNIX_Shell
UNIX Shell
function write { _.to_s > "$1" }
http://rosettacode.org/wiki/Bitmap/Write_a_PPM_file
Bitmap/Write a PPM file
Using the data storage type defined on this page for raster images, write the image to a PPM file (binary P6 prefered). (Read the definition of PPM file on Wikipedia.)
#Vedit_macro_language
Vedit macro language
///////////////////////////////////////////////////////////////////// // // Save image as PPM file. // @10 = filename. Buffer #10 contains the Pixel data. // :SAVE_PPM: Buf_Switch(#10) BOF IT("P6") IN Num_Ins(#11, LEFT) // width of image Num_Ins(#12, LEFT) // height of image Num_Ins(255, LEFT+NOCR) // maxval I...
http://rosettacode.org/wiki/Bitmap/Bresenham%27s_line_algorithm
Bitmap/Bresenham's line algorithm
Task Using the data storage type defined on the Bitmap page for raster graphics images, draw a line given two points with Bresenham's line algorithm.
#Action.21
Action!
INCLUDE "H6:RGBLINE.ACT" ;from task Bresenham's line algorithm   RGB black,yellow,violet,blue   PROC DrawImage(RgbImage POINTER img BYTE x,y) RGB POINTER ptr BYTE i,j   ptr=img.data FOR j=0 TO img.h-1 DO FOR i=0 TO img.w-1 DO IF RgbEqual(ptr,yellow) THEN Color=1 ELSEIF RgbEqual(ptr...
http://rosettacode.org/wiki/Bitcoin/address_validation
Bitcoin/address validation
Bitcoin/address validation You are encouraged to solve this task according to the task description, using any language you may know. Task Write a program that takes a bitcoin address as argument, and checks whether or not this address is valid. A bitcoin address uses a base58 encoding, which uses an alphabet of th...
#C
C
#include <stdio.h> #include <string.h> #include <openssl/sha.h>   const char *coin_err; #define bail(s) { coin_err = s; return 0; }   int unbase58(const char *s, unsigned char *out) { static const char *tmpl = "123456789" "ABCDEFGHJKLMNPQRSTUVWXYZ" "abcdefghijkmnopqrstuvwxyz"; int i, j, c; const char *p;   mems...
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed st...
#Factor
Factor
USING: checksums checksums.ripemd checksums.sha io.binary kernel math sequences ; IN: rosetta-code.bitcoin.point-address   CONSTANT: ALPHABET "123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz"   : btc-checksum ( bytes -- checksum-bytes ) 2 [ sha-256 checksum-bytes ] times 4 head ;   : bigint>base58 ( n --...
http://rosettacode.org/wiki/Bitcoin/public_point_to_address
Bitcoin/public point to address
Bitcoin uses a specific encoding format to encode the digest of an elliptic curve public point into a short ASCII string. The purpose of this task is to perform such a conversion. The encoding steps are: take the X and Y coordinates of the given public point, and concatenate them in order to have a 64 byte-longed st...
#Go
Go
package main   import ( "crypto/sha256" "encoding/hex" "errors" "fmt"   "golang.org/x/crypto/ripemd160" )   // Point is a type for a bitcoin public point. type Point struct { x, y [32]byte }   // SetHex takes two hexidecimal strings and decodes them into the receiver. func (p *Point) SetHex(x, y...
http://rosettacode.org/wiki/Bitmap/Flood_fill
Bitmap/Flood fill
Implement a flood fill. A flood fill is a way of filling an area using color banks to define the contained area or a target color which "determines" the area (the valley that can be flooded; Wikipedia uses the term target color). It works almost like a water flooding from a point towards the banks (or: inside the vall...
#Delphi
Delphi
def floodFill(image, x, y, newColor) { def matchColor := image[x, y] def w := image.width() def h := image.height()   /** For any given pixel x,y, this algorithm first fills a contiguous horizontal line segment of pixels containing that pixel, then recursively scans the two adjacent rows over the s...