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libcaca-tutorial.3caca

NAME

libcaca-tutorial - A libcaca tutorial First, a very simple working program, to check for basic libcaca functionalities.

 #include <caca.h>
 
 int main(void)
 {
     caca_canvas_t *cv; caca_display_t *dp; caca_event_t ev;
 
     dp = caca_create_display(NULL);
     if(!dp) return 1;
     cv = caca_get_canvas(dp);
 
     caca_set_display_title(dp, 'Hello!');
     caca_set_color_ansi(cv, CACA_BLACK, CACA_WHITE);
     caca_put_str(cv, 0, 0, 'This is a message');
     caca_refresh_display(dp);
     caca_get_event(dp, CACA_EVENT_KEY_PRESS, &ev, -1);
     caca_free_display(dp);
 
     return 0;
 }
 

What does it do?

*

Create a display. Physically, the display is either a window or a context in a terminal (ncurses, slang) or even the whole screen (VGA).

*

Get the display's associated canvas. A canvas is the surface where everything happens: writing characters, sprites, strings, images... It is unavoidable. Here the size of the canvas is set by the display.

*

Set the display's window name (only available in windowed displays, does nothing otherwise).

*

Set the current canvas colours to black background and white foreground.

*

Write the string 'This is a message' onto the canvas, using the current colour pair.

*

Refresh the display, causing the text to be effectively displayed.

*

Wait for an event of type CACA_EVENT_KEY_PRESS.

*

Free the display (release memory). Since it was created together with the display, the canvas will be automatically freed as well.

You can then compile this code on an UNIX-like system using the following commans (requiring pkg-config and gcc):

 gcc `pkg-config --libs --cflags caca` example.c -o example