Attachment 654931 Details for Bug 882185 – A program to change the colour of the terminal screen from value 0 to 255

A program to change the colour of the terminal screen from value 0 to 255

testing_colors.c (text/x-csrc), 3.33 KB, created by Kanda-kanda Malangu on 2012-11-30 11:03:01 UTC

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Creator: Kanda-kanda Malangu

Created: 2012-11-30 11:03:01 UTC

Size: 3.33 KB

patch

obsolete

>/*********************************** testing_colors.c ************************************
> *                                                                                       *
> * A program for observing the appearance of the 256 colors on the enhanced terminal.    *
> *                 								         *
> * AUTHOR: Kanda-kanda Malangu                                                           *
> *										         *
> * Date: Thursday November 29, 2012 at 00:30 EST				         *
> *****************************************************************************************/
>#include <ncurses.h>
>#include <string.h>
>
>#define NUMBER_OF_COLORS 256  // total number of colors for the enhanced terminal
>
>#define BLACK_COLOR 16  /* sets the "black" color to 16 instead of 0 because 16 seems to
>			   appear much darker than any other value in the range */
>                          
>#define WHITE_COLOR 231 /* sets the "white" color to 231 instead of 7 because 231 seems to
>			   appear much clearer than any other value in the range */
>
>void create_color_pairs(void);
>void print_message(int color_value, char *message);
>
>int
>main(void)
>{
>	char *greetings = "HELLO WORLD!";
>	int color_value;
>
>	if (initscr() == NULL)
>	{
>		fprintf(stderr, "Cannot initialize the standard screen for curses mode\n");
>		return 1;
>	}
>	
>	if (start_color() != OK)
>	{
>		endwin();
>		fprintf(stderr, "Cannot initialize the color mode on this terminal");
>		return 2;
>	}
>
>	noecho();
>
>	// initializes the 256 color-pairs designed for this test-program.
>	create_color_pairs();
>	
>	// prints 256 times the greetings on a different background color for each iteration. 
>	for (color_value = 0; color_value < NUMBER_OF_COLORS; color_value++)
>	{	
>		print_message(color_value, greetings);
>	}
>
>	endwin();
>	return 0;
>}
>
>/*
> * Creates only 256 color-pairs by setting a white foreground on 6 selected background colors
> * to ease comparisons and readability, and black foreground on the remaining 250 background
> * colors for the same raison. However for this enhanced terminal as many as 65,536 color-pairs
> * can be created.
> */
>void
>create_color_pairs(void)
>{
>	for (int color_value = 0; color_value < NUMBER_OF_COLORS; color_value++)
>	{
>		if ((color_value == 7) || (color_value == 15) || (color_value == 16) || (color_value == 187) || (color_value == 188) || (color_value == 230))
>			init_pair(color_value+1, WHITE_COLOR, color_value); // foreground is set to white
>		else	
>			init_pair(color_value+1, BLACK_COLOR, color_value); // foreground is set to black
>	}
>}
>
>/*
> * Prints the message passed to it as argument, along with other information, on a background
> * color determined by the parameter of the macro COLOR_PAIR(). It allows the user observe the
> * background color of the standard screen and consequently decide on the name of the color.
> */
>void
>print_message(int color_value, char *message)
>{
>	int n = strlen(message);
>
>	// the value to be passed to the macro COLOR_PAIR() should start from 1 up to 256
>	bkgd(COLOR_PAIR(color_value+1)); 
>
>	mvprintw(LINES/2, (COLS-n)/2, message);
>	mvprintw(LINES-5, 5, "This background color has value %3d. Which color do you think it is?", color_value);
>	if (color_value != 255)
>		mvprintw(LINES-3, 15, "Press any printable key to see the next background color.");
>	else
>	{
>		move(LINES-3, 0);
>		clrtoeol();
>		mvprintw(LINES-3, 15, "That's it! Press any key to quit");
>	}
>			
>	refresh();
>	getch();
>}
>

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Attachments on bug 882185: 654931