Flashing Text in Linux Terminal
I know its not portable either in terms of OS or CPU speed, but I want to learn some
basic graphic functionality in Windows and Linux before moving on to consider cross
-platform API's. So I'm really just interested in how I can create flashing text in
the Linux terminal window using escape codes.
In Windows the move from static to dynamic was trivial and I ended up creating a
naff flashing "Merry Xmas" sign, which I would like to replicate in Linux.
In Windows all I really needed to do was print a bright character,pause then
print its dimmer companion,pause then keep looping.
In Linux that just doesn't work,I get weird synchronisation effects and white versions
of the characters appearing instead of the coloured ones that are supposed to etc.
The only half-clue garnered from the internet was a small sentence that said "blink"
doesn't work in a terminal emulator. Which I understand is the type of terminal I am
using in a GUI Linux like the Puppy Linux I'm using.
Well I'm not using the blink attribute but it makes me think that maybe it just can't
cope with this kind of graphic switching?
The code here just prints 2 of the characters, and because I've got a white terminal
window background I first create a black background for the minimised window.
Anyone any ideas?
Code:
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#define ALL_NORMAL "\033[0m"
#define BG_BLACK "\033[40m"
#define BLACKBACK BG_BLACK " " ALL_NORMAL
#define REVERSE "\033[7m"
#define FG_RED "\033[1;31;40m" // bright red black bg
#define FG_MAROON "\033[2;31;40m" // dark red black bg
#define FG_YELLOW "\033[1;33;40m" // bright yellow black bg
#define FG_DYELLOW "\033[2;33;40m" // dark yellow black bg
#define BRIGHT_RED_M FG_RED "M" ALL_NORMAL
#define DIM_RED_M FG_MAROON "M" ALL_NORMAL
#define BRIGHT_YELLOW_R FG_YELLOW "R" ALL_NORMAL
#define DIM_YELLOW_R FG_DYELLOW "R" ALL_NORMAL
void set_coord(int x, int y);
void plot_char(int x,int y,char *char_string);
int main(void)
{
int x,y,timer;
system("clear");
for(x=0;x<80;x++) //set background black
{
for(y=0;y<25;y++)
{
plot_char(x,y,BLACKBACK);
}
}
while(1)
{
plot_char(20,10,BRIGHT_RED_M);
plot_char(22,10,BRIGHT_YELLOW_R);
timer = 0;
while(timer < 10000000)
{
timer++;
}
plot_char(20,10,DIM_RED_M);
plot_char(22,10,DIM_YELLOW_R);
timer = 0;
while(timer < 1000000)
{
timer++;
}
}
return 0;
}
void set_coord(int x, int y)
{
printf("\033[%d;%dH",y,x); // move cursor (row x, col y)
}
void plot_char(int x,int y,char *char_string)
{
set_coord(x,y);
fputs(char_string,stdout);
//printf("%s",char_string);
}
